Author: ecogrow

A test run was conducted on 10 October 2013 to determine the optimal runoff sampling time intervals and the number of samples needed to capture the peak and total loadings. For the test run, the water soluble fertilizer was applied to both of the sites at a rate of 2.24 g m−2 . Grab samples were collected at a 10-min frequency over a two hour irrigation period from the control site. Water samples were collected immediately before the runoff was directed to the underground tank. The water samples were coarse filtered during sample collection with coffee filters to remove large tree leaves, grass clippings and large soil particles. Based on the results of the test run, the water sampling frequency for subsequent trials was extended to six hours with a variable sampling interval to better characterize the runoff pollutant pattern. The composite water sample from the treatment site was used for calculating the total loading of the treatment site where little surface runoff occurred in this study. A 5.1 cm diameter and 0.9 m long PVC drainage pipe was vertically installed into the middle of the treatment bioswale to collect a representative water sample for monitoring pollutants concentration dynamics in the bioswale. The treatment site water samples were not affected by successive flow from the control site because the treatment site was located upslope of the control site. The water sample collected from the control site was surface runoff, which was not affected by subsurface flow of the treatment site because of the site’s relatively flat surface. The oomycete pathogen Phytophthora cinnamomi Rands, procona buckets causal agent of Phytophthora root rot , is the most destructive disease of avocado worldwide .

In California, avocado PRR affects 60-75% of avocado growers who lose approximately $40 million annually . This globally distributed oomycete is called “the biological bulldozer” for its capacity to infect over 3000 plant species causing devastating impacts in natural ecosystems, forestry, agriculture, and the nursery industry . The economic impact due to P. cinnamomi infestation is evident in the forest and food industry, affecting eucalyptus, pine, oak , and other fruit crops such as pineapple, peach, and high bush blueberry . Losses include not only decreases in crop yield and product value, but also large amounts of money spent annually on control measures. There are no effective means to eradicate P. cinnamomi from infested areas as it survives in moist soil or dead plant material as chlamydospores for long periods under adverse conditions . Several PRR control strategies have been found to reduce the impact of this invasive pathogen including the use of chemical treatment , tolerant plants, and management practices . P. cinnamomi is a hemibiotrophic pathogen feeding initially from living host cells and then switching to necrotrophy by killing the host cells and feeding from the nutrients released by them . The entry into the plant is achieved by the adhesion of the motile zoospores to the host tissue, encystment, and germ tube formation. The germ tubes usually grow and penetrate the root surface via appressorium like swelling structures and then plant tissue is rapidly colonized . During its biotrophic stage, P. cinnamomi projects haustoria into the plant cells for the acquisition of nutrients and release of pathogen proteins to aid the infection process in the host . This is followed by a necrotrophic stage characterized by host cell death, hyphal proliferation, and production of numerous sporangia .

Currently, the molecular and genetic basis of P. cinnamomi pathogenicity, virulence, and plant immunity against this pathogen are largely unknown due to limitations associated with tree crop biology and the lack of tools available for functional studies in tree crops such as avocado . The model plant, Nicotiana benthamiana , has been widely used to study the pathogenicity and virulence of similar broad range and root Phytophthora pathogens such as P. capsici , P. palmivora , and P. parasitica . Moreover, several studies using model plants, crops, and tree crops to study pathogenicity, virulence, and fungicide efficacy of PRR pathogens such as P. sojae, P. capsici, P. parasitica, P. palmivora, P. cinnamomi, and P. ramorum have been done using detached-leaf assays . Phosphite is the most widely used chemical control method for managing PRR caused by several Phytophthora spp. including P. cinnamomi . Phosphorous acid dissociates to form the phosphonate ion , also called phosphite. Phosphorous acid and its ionized compounds are often referred to as phosphonate or phosphonite. The specific mode of action of potassium phosphite is largely unknown, however appears to involve both a direct and an indirect effect on the pathogen . Several studies have assessed the in vitro sensitivity of P. cinnamomi to phosphite using mycelial radial growth inhibition in solid and liquid media to identify sensitive and tolerant isolates . In California, avocado growers heavily rely on the use of phosphite products to control P. cinnamomi, however the phosphite sensitivity of California avocado isolates is largely unknown. In addition to phosphite, phenylamide fungicides such as metalaxyl and mefenoxam are also used for managing diseases caused by oomycetes including P. cinnamomi . Resistance to metalaxyl has developed in P. capsici, P. infestans, and P. nicotianae . Phenylamides usually do not inhibit germination of sporangia or encysted zoospores as effectively as they do mycelial growth . Consequently, inhibition of mycelial growth in vitro has been used as the primary method of determining the sensitivity to these fungicides among isolates of Phytophthora spp. .

The need for new oomycete-targeted fungicides to control diseases caused by these pathogens especially those that have developed resistance to phenylamide fungicides has resulted in the development of several new chemicals with varying modes of action such as fluopicolide and oxathiapiprolin . Fluopicolide is a pyridinylmethyl-benzamide fungicide that disrupts cell division and mitosis by acting on spectrin-like proteins . This fungicide is effective to control diseases caused by P. capsici and P. infestans . Oxathiapiprolin is the first of the new piperidinyl thiazole isoxazoline class fungicides discovered and developed by DuPont Co. in 2007. The molecular target of oxathiapiprolin is the oxysterol binding protein . This new fungicide exhibits strong inhibitory activity against a range of agriculturally important plant-pathogenic oomycetes including P. capsici, P. infestans, P. sojae, Peronospora belbahrii, and Pythium ultimun . However, its inhibitory activity against P. cinnamomi has not been tested. P. cinnamomi is a heterothallic species that requires the presence of both A1 and A2 mating types to undergo sexual reproduction. Despite that both mating types arepathogenic , avocado PRR disease in California is mainly associated with A2 mating type isolates . Previous P. cinnamomi population studies have revealed low levels of genotypic and phenotypic variation among isolates from different mating types, origin, isolation source, and host plants, however, only a few were conducted or have included isolates from avocado . These studies described the existence of three clonal lineages for P. cinnamomi, one corresponding to the A1 mating type isolates and two different clonal lineages for the A2 mating type isolates . Pagliaccia et al. conducted the first study to assess the genetic diversity of P. cinnamomi isolates from avocado in California and also found two genetically distinct clades of A2 mating type isolates . The A2 clade II consisted of isolates with unique genotypes collected only in Southern California. Interestingly, the authors in this study included isolates from P. cinnamomi previously identified as belonging to the A2 type 1 and A2 type 2 described by Dobrowolski et al. , however these isolates clustered within the A2 clade I group, suggesting that the A2 clade II group identified in Paglaccia et al. in California could be another clonal lineage. No studies have been conducted to assess the phenotype of avocado isolates corresponding to these genetically distinct A2 groups identified in California by Paglaccia et al. , therefore, procona florida container the objectives of this study were to i) assess the phenotype of several avocado isolates corresponding to these A2 clades regarding in vitro mycelial growth rate, optimal growth temperature, sensitivity to potassium phosphite and mefenoxam, and virulence, ii) test the sensitivity of avocado isolates to fluopicolide and oxathiapiprolin as alternative chemistries for controlling avocado PRR in California, and iii) develop and validate a detached leaf assay inoculation method using N. benthamiana to circumvent the difficulties associated with the avocado whole plant root inoculation method to assess the virulence of P. cinnamomi isolates. This information will help to design appropriate measures for managing avocado PRR in California and implement efficient and reliable screening methods towards the selection and development of new P. cinnamomi resistant avocado rootstocks effective against a more diverse pathogen population.A total of twelve P. cinnamomi isolates associated with avocado PRR were used in this study, including six isolates from Northern California corresponding to the A2 clade I group, four isolates corresponding to the unique A2 clade II subpopulation from Southern California, and two isolates collected from the same Southern California region from where the A2 clade II isolates were collected .

A2 clade I isolates from this study represent five of the ten total genotypes identified by Paglaccia et al. . Isolates representing the A2 clade II group covered three from the six unique genotypes identified in Southern California. All the isolates in this study were obtained from a P. cinnamomi small collection at the UCR Avocado Rootstock Breeding Program. Isolates were maintained as water agar plugs . Agar plugs were removed one at the time as needed for each experiment and plated on 10% clarified cV8A agar to resume growth. To ensure that isolates in the collection are free of contamination and avoid any problems with mix samples or not appropriate maintenance of the collection, we sequenced all the isolates using ITS and COX1 spacer regions. Mycelial DNA was extracted using the Qiagen DNeasy plant mini kit . Universal primers ITS1 and ITS4 were used for the ITS region, and primers OOM and FM85 were used for the COX1 spacer region, both sets of primers are described in Kroon et al. . Each 25-µl PCR reaction contained 2 µl of DNA , 2.5 µl of 10x PCR buffer , 200 µM dNTPs, 0.4 µM of each primer, and 1.25 units of Taq DNA polymerase . PCR reactions were performed using a Programmed Thermal Controller with conditions as follows: 95°C for 5 min; followed by 35 cycles at 95°C for 1 min, 50°C for 1 min, and 68°C for 1 min; and a final extension at 68°C for 10 min. PCR products were confirmed on 1% certified molecular biology agarose gel , stained with ethidium bromide , and visualized under UV light using a Universal Hood UV Light Table . PCR products were treated with Zymo DNA Clean and Concentrator according to the manufacturer’s instructions to remove excess primers and nucleotides before submitting the samples for Sanger sequencing. DNA sequencing was conducted in both directions with the same primers used for amplification at the UCR Genomics Core facility. Contiguous sequences were generated which were then subjected to a BLASTn search to determine the highest maximum identity to the sequence of the type isolates in GenBank.Two avocado rootstocks were selected based on their P. cinnamomi resistance phenotype. Clonal rootstocks corresponding to the moderate resistant Dusaâ and the susceptible PS.54 were obtained from Brokaw Nursery. The 6-month-old clonally propagated plants were removed from their bags and transplanted into pots after the nurse seed was removed. Plants were grown in a greenhouse with an average maximum temperature range of 25-28°C at 40-50% relative humidity. Plants were fertilized twice a week and watered every day. Nicotiana benthamiana seeds were germinated in trays and transferred to individual pots 2 weeks post germination. Plants were grown at 22°C with 16 h of light and 8 h dark cycles at 40-50% relative humidity. The effective concentration of potassium phosphite at which 50% of the mycelial growth of each isolate was inhibited was determined using the traditional agar dilution method as described in Adaskaveg et al. . Potassium phosphite was added to 10% cV8A to obtain final concentrations of 5, 25, and 100 µg/ml. Mycelial agar plugs from 6-day old cultures of P cinnamomi were placed at the center of the plates containing the corresponding chemical concentration. Three replicates were done per each treatment. After incubation for 3 days in the dark at 22°C, radial colony growth was measured. Colony growth inhibition of each isolate in the presence of potassium phosphite was then calculated as compared with their corresponding control plates without potassium phosphite.

The leaf positioned at the front of the cluster was specifically selected, and the petiole was immediately separated from the blade. The petioles were transported to the laboratory, where they were triple-washed with distilled water to remove any impurities before being sent to a private laboratory for nutrient analysis. In the winter, soil samples were collected at a depth of 30 cm and at a distance of 30 cm from the vine. These samples were transported immediately to the laboratory for analysis. The nutrient content was determined using the methods described in US Salinity Laboratory Staff .The taste panel evaluation of Scarlet Royal table grapes was conducted with the participation of twelve nonprofessional panelists. Astringent taste perception was assessed using a scale ranging from one, representing an extremely low level of astringency, to seven, indicating an extremely high level of astringency. The taste evaluation was performed on 24 clusters from each vineyard. Phenolic compounds analysis. Total phenolic analysis was performed on 250 grams of whole berries by ETS laboratory using a reversed-phase HPLC method adapted from Price et al. .Total RNA was isolated from whole berry samples following the protocol described by Boss et al. . To remove any residual DNA, RNase-free RQI treatment was performed according to the manufacturer’s instructions , and the samples were further purified using the RNeasy mini kit . For RNA-seq analysis, a total of 8 RNA-seq libraries were generated, plasit plant pot comprising four biological replicates from each of the two vineyards . The libraries were constructed as previously described using the NEBNext Ultra II RNA Library Prep Kit for Illumina .

Subsequently, these libraries were pooled in equal amounts and subjected to paired-end 150-base sequencing on two lanes of the NovaSeq 6000 platform at the Novogene Co., Ltd .Illumina sequencing of the multiplexed RNA-seq libraries resulted in 8 FASTQ files containing sequences, and the dataprocessing followed the methods described in our previous work . In summary, the quality of reads was assessed using FASTQ before and after trimming with Trimmomatic v0.39 . Subsequently, the trimmed reads were quantified using Salmon in non-alignment based mode to estimate transcript abundance . The transcripts were mapped to the Vitis transcriptome file “Vvinifera_457_v2.1.transcript_primaryTranscriptOnly.fa” extracted from Phytozome database , resulting in a mapping rate higher than 61.9% . To identify differentially expressed genes between V7 and V9 at the sampling point, we utilized the DESeq2 and EdgeR packages with default parameters . For convenience, the DEGs generated by both DESeq2 and EdgeR pipelines, with a threshold of PFDR<0.05 and log2fold change > 1.5 or < –1.5, were considered as being expressed . For the analysis of Gene Ontology terms, we employed the g:Profiler website with the g:SCS multiple testing correction method, using a significance threshold of 0.05 . Finally, to visualize the consensus result, the Web-based tool Venny was used .Despite the premium fruit quality of the variety, in some cases, an undesirable taste was observed under certain unknown circumstances. To gain comprehensive insights into the development of the occasional berry astringency of Scarlet Royal and understand the underlying mechanism of this phenomenon, berries were investigated at two contrasting vineyards , both following the same commercial cultural practices. However,leaf petioles analysis of grapes from both vineyards showed considerable differences in nutrient levels, especially in the primary macronutrients .

During both seasons, the amount of nitrogen in the form of nitrate in LP-V9 was roughly 2 to 3 times higher than the normal levels, in contrast to its counterpart in LP-V7, which slightly accumulated more or less N. Similarly, LP-V9 contained higher percentages of phosphorus and potassium compared to LP-V7 . Conversely, the amounts of secondary macronutrients, calcium and magnesium , in LP-V7 were within the normal range but greater than LP-V9, which showed Mg deficiency in the first year only. Regarding the micronutrients, their levels were mainly within or around the normal range at both vineyards and during both seasons, with some differences . For example, zinc was slightly higher in LP-V9, especially in the first year. On the contrary, manganese and chlorine were roughly 2 times higher in V7 . Similarly, soil analysis shoed a higher level of nitrogen, potassium and magnesium . However, no significant difference was observed in all other soil macro and micronutrients. During the two seasons of the study, we determined the total marketable yield and the number of clusters in both vineyards. Our data revealed a higher yield in V7 compared to V9 in 2016 and 2017, respectively. The lower yield in V9 can likely be attributed to the smaller number of clusters in V9 compared to V7 during 2016 and 2017. To monitor the changes in the biochemical composition of Scarlet Royal berries, V7 and V9 berries were periodically sampled at six time points from veraison until the end of the season . The obtained data showed that berry polyphenols exhibited discernible patterns in both vineyards, most notably during the ripening stage . Of special interest were the tannin compounds, which widely affect organoleptic properties such as astringency and bitterness . Our data showed that berries from both V7 and V9 vineyards maintained lower levels of tannin from veraison up to the middle of August . Subsequently, a significant gradual increment of tannin took place. However, only V9-berries showed consistent accumulation of tannin over the two studied seasons compared to V7-berries, where the significant induction occurred only during the first season.

It is worth noting that the levels of tannin were lower in both vineyards during the second year compared to the first season. Nevertheless, they were more pronounced in V9-berries compared to V7-berries, with roughly 2- to 4.5-fold increases by the end of the harvesting time during the two seasons, respectively . The patterns of catechin and quercetin glycosides were inconsistent during both seasons, particularly within V7-berries . During the first year, for instance, the levels of catechin were similar in both vineyards, showing a dramatic increase only by the end of the season . In contrast, during the second year, such induction of catechin was exclusively restricted to V9-berries, starting from time S3 . For quercetin glycosides, V7-berries exhibited significantly higher amounts at early stages during both seasons relative to V9-berries . However, subsequent amounts were comparable in both vineyards during the first season only , but not in the second one, where V7-berries showed a significant drop at the last sample S6 . Interestingly, the levels of quercetin glycosides were roughly equal at the last V9-berries sample between both seasons despite such inconsistency. For total anthocyanins , the levels in early samples were comparable in both vineyards and seasons . Afterwards, their pattern started to vary between V7 and V9 within the same season, as well as from the first season to the second, as the nutrient amounts fluctuated as well . Nevertheless, TAC accumulation was positively correlated with the progress of ripening in V7-berries, but not V9-berries. To further confirm our data, we measured these phenolic compounds for the third time in mid-September of the next year . Overall, the results showed that the patterns of tannins and TAC were reciprocally inverted between V7-berries and V9-berries as ripening advanced. In addition, both catechin and quercetin glycosides most likely followed the pattern of tannins despite their seasonal fluctuations. To further distinguish V7-berries and V9-berries and assess their astringency development, a panel test was performed using samples at three commercial harvest times . A group of 12 nontechnical panelists scored berry astringency on a scale from 1 to 7, plastic planter pot where 1 is extremely low and 7 is extremely high. The panelists were trained using samples from contrasting standard varieties, including Flame Seedless and Crimson as non-astringent and Vintage Red known for its astringent taste . The results showed that V7-berries exhibited lower intensity of astringency compared to V9-berries . As ripening proceeded, astringency levels increased in V9-berries, but decreased in V7-berries. Moreover, we collected samples from clusters with various astringent taste and measured its tannins content. We were able to determine that the threshold level of tannins that causes the Scarlet Royal astringency taste is around 400 mg/L . Taking into account the levels of polyphenol compounds and the taste panel data together , it is evident that astringency development is positively associated with tannins’ accumulation throughout the ripening process of V9-berries. Nevertheless, organoleptic analysis revealed a significant difference in the berries of the two vineyards, particularly in terms of total soluble solids and titratable acidity . Notably, V9 berries exhibited higher titratable acidity and lower total soluble solids, especially in the later stages . It’s worth noting that the weight of V9 berries is also higher than that of V7 .To better understand the molecular events associated with the induction of tannins and astringency upon ripening, the berry transcriptome profile was analyzed in both V7-berries and V9- berries at the late commercial harvest date . Following the quality and quantity check, extracted RNA from quadruplicate samples was deeply sequenced .

Of the 19.7 to 24.4 million high-quality clean reads per replicate, 61.9% to 66.1% were mapped against the V. vinifera transcriptome . Hierarchical clustering of the RNAseq data showed explicit changes in the berry transcriptome profile between V7- berries and V9-berries . The Principal Component Analysis showed high consistency among biological replicates . Samples were mainly separated along the first component , which was responsible for 97% of the variance, and was definitely associated with the site of cultivation; V7 and V9. In contrast, the second component was trivial, accounting for only 1% of the variance and was probably attributed to experimental error. Such results were expected, as berry samples came from the same cultivar, Scarlet Royal , and the only difference between them was the vineyard locations. To identify the differentially expressed genes in V7- berries and V9-berries at this specific time within the ripening window, the RNAseq data were analyzed using two different Bioconductor packages, DESeq2, and EdgeR . Subsequently, the DEGs with FDR < 0.05 and log2fold change > 1.5 or < –1.5 generated by both pipelines were considered . The pairwise comparison between berry transcriptomes resulted in 2134 DEGs, with 1514 up-regulated and 620 down-regulated . The data manifested the impact of the cultivation site on the transcriptional reprogramming of a large number of genes that ultimately affect berry quality. Most apparently, at the V9 vineyard, where roughly 2.5-fold higher number of berry transcripts were upregulated compared to V7 . Subsequently, the enrichment of Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways were analyzed among the up- and down-regulated DEGs using the Vitis vinifera Ensembl GeneID . Among the significantly enriched GO terms, the up-regulated transcripts in V9-berries exhibited high enrichment in the molecular function GO terms for quercetin 3-O-glucosyltransferase activity and quercetin 7-Oglucosyltransferase activity . Additionally, the V9-berries induced DEGs were highly enriched in the biological process GO terms for the jasmonic acid signaling pathway and cellular response , Lphenylalanine metabolic process , L-phenylalanine biosynthetic process , and nitrogen compound metabolic process . Similarly, these DEGs were highly enriched in the KEGG pathways for the biosynthesis of secondary metabolites and phenylpropanoid biosynthesis . On the other hand, the down-regulated transcripts in V9-berries showed substantial augmentation in the MF GO terms for hormone binding , abscisic acid binding , and potassium ion transmembrane transporter activity . Correspondingly, the BP GO terms for hormone-mediated signaling pathway and response , auxin-activated signaling, cellular response, and homeostasis , abscisic acid-activated signaling, response, and cellular response , response to strigolactone , potassium ion transmembrane transport , and potassium ion transport , as well as the KEGG pathways for plant hormone signal transduction , brassinosteroid biosynthesis , and carotenoid biosynthesis were highly enriched in the down-regulated genes of V9-berries . Overall, the transcriptome analysis pointed out the substantial changes in transcript abundance that coordinate and reflect the observed induction of tannins/astringency during the maturation and ripening of V9-berries compared to the V7-berries .To elucidate which fundamental processes were altered during tannins/astringency induction within berries, the Weighted Gene CoExpression Network Analysis was applied to construct coexpression networks. Forty-two modules were identified based on pairwise correlations among the 17553 non-lowly expressed genes .

Binational workers, to be sure, own property in their home communities and view Mexico as their principal residence even when most household members may be in Santa Maria during the greater part of the year. Their domestic economy integrates resources and earnings on both sides of the border to, on one hand, support all family members and, on the other, to improve homes, farms, and businesses in Mexico. Typically, they save and accumulate earnings in Santa Maria to invest in Mexico in the hopes of developing a resource base that will eventually allow the family to live there permanently with security and in comfort. A few, however, are inadvertently becoming deeply rooted to Santa Maria and will likely end up forming part of the valley’s burgeoning community of immigrant farm workers. Most binational workers interviewed in 1991 and 1993 are from the same central states of Mexico where most of the immigrant settlers originate; only a few, 16 percent, are from the southern state of Oaxaca and none from the northern border states. Binational workers were at one time braceros who during the program years used earnings in California to assist their rural homes and families in Mexico. Even after the Bracero Program was cancelled, they continued to participate in the annual sojourn despite increased costs and risks brought about by the illegality of the practice. In fact, it is because travel and illegal border crossings became burdensome, expensive and risky that some ex-braceros who did not own farmland in Mexico decided to settle in the Santa Maria Valley with their families ; in contrast, plastic pots large exbraceros who did own farmland at home or had been awarded an ejido plot by the government’s land reform programs continued to migrate seasonally to California in search of earnings to improve their holdings in Mexico.

In the mid-to-late 70s, when high-value specialty crops took-off, migrant ex-braceros began to remain in the Santa Maria Valley during considerably longer periods of timeóup to nine or ten months rather than the former three to five months. In fact, under favorable climatic conditions, it was not unusual for a closing farm season to nearly overlap with the opening of a new one, forcing migrant farm workers to shorten their visits home or forgo them altogether. The successful development of specialty crops also created more job opportunities which were quickly filled primarily by ex-bracero relatives, often by the grown children of ex-braceros themselves. Although all this was a boon to migrant workers’ earning capacity, it also bore a painful hardship owing to difficult and prolonged family separations. Regularly employed migrant farm workers, as a result, began to establish temporary second homes in the valley to accommodate several related workers and to cut costs during the annual sojourn. They, moreover, transplanted other family members, mostly women, to provide a home environment and infrastructure, as well as to increase family wage earnings by placing them in occasional part-time farm jobs. Once installed in Santa Maria, children were also transported, among other reasons, to access better schools than those available to them in rural Mexico. An outcome of this behavior is the establishment of binational families who manage and share two sets of resources, one in each country, with members who shuttle back and forth between them with remarkable ease and frequency. Surveys conducted in 1991 and 1993 reveal that binational workers, like settled immigrants, enjoy the valley’s best farm jobs, especially the older more experienced workers who know the job market well and have developed good relations with local employers. Individual monthly earnings, as a result, range from $1,000 to $1,200. Although many are involved with vegetables, a sizeable number also are employed by strawberry farms as part of a core group of “privileged” workers who are the first to be hired when the harvest season begins in March/April and the last to be dismissed when the season ends in September/October. Binational families are large and complex. All of them, without exception, form extended family groups which operate as a single economic unit.

Typically, they include three to six nuclear families, three to four distinct generations, and as many as 25 to 40 individuals, more than one half of them being children under 15 years of age. Binational families work in teams; while one part, usually the least productive, remains in Mexico managing the homestead and caring for both the very young and very old, the most productive members and some school-age children journey to Santa Maria for variable periods of time. During spring and summer a sizable number are employed in the valley but in the autumn, when farm jobs begin to taper, unemployed members immediately trek back home to assist in the corn harvest there and to help keep costs down in Santa Maria. In late November only a skeleton group remains in the valley, along with some school children, and by Christmas it is oftenpossible to find the whole extended family group gathered in Mexico for a brief, fleeting instant. Soon afterwards, however, workers begin to drift back. In February, the northward movement begins in earnest and by May all employable members are back in Santa Maria. Binational families need to carefully and effectively coordinate the deployment and employment of their workers to ensure a maximization of the resources at their command. Because binational families place a large number of workers in the job market and, in the process, keep expenses down by maintaining a rural homestead in Mexico and temporary living quarters in Santa Maria, they are able to assemble a considerable family income even when individual wages are low or negligible. It is not common for binational workers to seek employment outside the Santa Maria Valley, away from their post; rather, they return to Mexico as soon as jobs become scarce. Binational households in Santa Maria contain a surprisingly large number of legal, documented migrants. Many of the first-generation ex-braceros still carry and use the micas issued to them in the late 60s by INS to commute across the border; others have subsequently exchanged these micas for “green cards” and, in the process, become legal residents.

Many of the undocumented, especially those who had evidence of employment, were able to legalize their status and obtain work authorization through IRCA’s General Amnesty and Special Agricultural Workers programs before the end of the 80s. The fact that so many workers are documented has not diminished their binational involvement; rather, documentation has just made it easier for them to shuttle between the Mexican homestead and the Santa Maria extension. Many, nonetheless, remain illegal. This is especially the case of women and children who did not qualify for the SAW program and, as a result, continue to cross the border clandestinely. It is not unusual for authorized workers to share their documents with undocumented kin to facilitate border crossings and to seek employment. The exact enumeration of binational migrants faces two inextricable complications: First, the extraordinary and often unpredictable mobility of household members may easily cause a house-to-house survey to elicit as few as 3 to 5 members one day and as many as 18 to 20 on another. Second, binational households contain a substantial number of undocumented/unauthorized residents, especially women and children, who need to be concealed and protected. Binational migrants are, to say the least, always apprehensive about providing correct, complete, and reliable information regarding the size and composition of their households. Not to be mistaken with the above-described binational workers are the approximately six to seven thousand migrants who regularly sojourn to the Santa Maria Valley to harvest fruit and vegetable crops. These are migrant workers who are firmly rooted to their Mexican home communities, where they maintain a permanent domicile, but who regularly migrate to California looking for seasonal farm jobs and wages to send back home. They are, in a sense, black plastic nursery pots the braceros of today without a Bracero Program. Many originally became involved in this annual trek in the 1940s when the Bracero Program was first established and have maintained the practice ever since by passing it from one generation to the next even after the program was terminated in 1964, converting the practice into a deeply embedded tradition. Families who participate in this tradition have organized their lives and households in a manner which enables workers to migrate and, as a result, wage remittances have become an intrinsic and indispensable part of the household economy . A key distinction of the seasonal migrant, vis-a-vis the binational worker, is that only the most productive and employable workers migrate. Less productive workers and dependents are always left behind in the home community to tend the family farm or just simply to survive on the basis of a, hopefully, steady flow of wage remittances arriving from the United States.

Many will return home as soon as the employment season ends or sooner if a pre-targeted goal of earnings is accomplished. They, in short, only come to work and earn wages, and they are with few exceptions always in a hurry to return home. Seasonal migrant workers occupy a particular niche in the farm-labor market and production cycle of Santa Maria Valley agriculture. They serve as a labor reserve which intermittently complements year-round vegetable harvest crews during the peak spring and summer months when crops tend to mature faster, even bolt, with the arrival of longer days and warmer temperatures. And they especially supply the bulk of the peak harvest labor for strawberries and wine grapes during the spring-to-summer and early autumn months, respectively. Although the presence of seasonal migrants in Santa Maria diminished considerably during the 80s as immigrant workers settled permanently in the valley, they began to increase again in the 90s as strawberry acreage expanded and farm employment practices changed owing to IRCA impacts. In effect, the recent proliferation of farm labor contractors has often placed migrant workers in direct competition against the stable but more expensive local immigrant laborer. Nonetheless, migrant workers do not enjoy the better paid, more stable, and skilled farm jobs which continue to be largely monopolized by immigrant and binational workers. Migrants, to be sure, hold the most seasonal, insecure and intermittent farm jobs with monthly earnings which range between $500 to $800 during the peak employment season. Interviews conducted among seasonal migrants during the 1993 campaign, especially among strawberry harvest crews, revealed that there are two distinct sub-types of migrants: first, the descendants of braceros, those who have established a tradition of migration, from the sending communities located in the central states of Guanajuato Jalisco, Michoacan, and Zacatecas; and second, new immigrants mostly from the southern states of Oaxaca and Guerrero. Traditional migrants have established effective networks and accrued experience which facilitate travel, border crossings, and employment. Some have kin and friends established permanently in the Santa Maria Valley who provide sanctuary and assistance during the annual trek. Others rent apartments or rooms for the season and share them with other migrants to cut living expenses during their stay in the valley. They, moreover, have considerable personal access to farm employers who hire them year after year. Many come to Santa Maria only to perform a specific job with a specific employer and return home with their savings as soon as the season concludes. Although many travel from Mexico alone, especially those who have kin in the valley, it is quite common to find cohort groups sojourning together, either groups of friends and neighbors of a similar age, or multi-generational kin-based groups. The presence of women workers among migrants is not uncommon, especially among family groups, but men continue to predominate in the ranks of the sojourn workers. In 1993, approximately forty percent of the interviewed migrants fit the description of traditional migrants. New migrants account for the remaining sixty percent of the migrant labor force observed in the Santa Maria Valley in 1993. As stated above, most come from the southern states of Oaxaca and Guerrero; many are Mixtec and Zapotec Indians. Few have a California migration experience of more than ten years, though most have lived the lives of migrants as seasonal farm workers laboring in the northwestern states of Sinaloa, Sonora, and Baja California in Mexico. In recent times they have included the United States’ west coast as part of their itinerary.

Like strawberries, raspberries and blackberries have benefitted from enhancements in cultural practices. When well-managed, both types of caneberries can produce crops for up to 20 years. However, to maintain acceptable quality and yield Central Coast growers typically manage raspberries and blackberries so that they produce two and five crops, respectively, prior to removal and replanting. In Santa Cruz County, raspberry production was relatively flat in the 1960s and 1970s, but began to increase substantially in the 1980s . This can be explained by a shift from floricane, or spring-bearing varieties, to the then newly developed proprietary primocane, or fall-bearing varieties, that do not carry the productivity constraints associated with the inadequate chill requirements along the Central Coast. Primocane-bearing varieties allow growers to successfully produce a high quality raspberry crop in low- or no-chill coastal locations, and further manipulate time to harvest and yield with pruning and other management practices . Between 1990 and 2014, the number of acres planted to Santa Cruz and Monterey area raspberries almost tripled, tons produced increased by about 350% and the value of production was up by over 400% in real dollars . Santa Cruz County raspberry growers began to experiment with and adopt field-scale semi-permanent protective structures or tunnels in the 1990s and 2000s . Initially developed in Europe, field-scale tunnels allow growers to extend their production seasons, enhance yield and fruit quality, and capture high off-season prices for fresh market fruit . The controlled environment, and resulting security of production, also allows for greater market stability. Tunnel culture is now a common practice in raspberry production. This shift away from open-field production to protected cropping, growing raspberries in container along with breeding improvements, has had lasting impacts on the raspberry industry and its expansion.

Cultural improvements geared towards fresh market blackberry production are more recent and include advances in breeding for thornless varieties and quality attributes . In 2011, a public primocane-bearing blackberry variety became commercially available for the first time and is now being planted in the area. Since that time, additional public and proprietary primocane-bearing varieties have been in development; some have already become available. Open-field production was the norm until recently, but to ensure marketable fruit of high quality, and as growers have shifted additional acreage to primocane-bearing varieties, tunnel culture has been more widely adopted and, based on discussions with growers, is now estimated at roughly 80% of the acreage. Like organic strawberries, remarkable growth in the statewide production of organic raspberries and blackberries was documented between 2000 and 2012 . Value of production was up over 3,000% in real dollars for organic raspberries and up by almost the same percentage for organic blackberries. It is important to note that although the organic raspberry and blackberry categories have demonstrated extraordinary growth, they still represent a relatively small percentage of all berry production in the area. Research points to several factors that have spurred consumer demand for all berries. Berries contain bioactive compounds, including essential vitamins, minerals, fiber and antioxidants that contribute to healthy diets, and that help to reduce the risks associated with some chronic diseases and cancers . This information has been widely shared with consumers through, for example, government programs promoting healthy eating , and more generic berry promotion programs . Per capita consumption of fresh strawberries in the United States almost doubled from 1994 to 2014, increasing from 4.1 to 8.0 pounds . U.S. per capita consumption of fresh raspberries was small by comparison, at just 0.5 pounds in 2014. Similar consumption data are not available for blackberries, but Cook notes that consumers generally view berries as complementary, and that sales for all berries have increased.

Indeed, in 2014, berry sales increased 5.8% over 2013; berries were the number one produce category for U.S. grocery retailers, at $5.7 billion in annual sales . Some berry operations also benefit from their proximity to the area’s urban centers, which have sizeable cohorts of educated, high-income consumers who generally demonstrate an interest in health and wellness, local agriculture and fresh and organic products. In addition to the more traditional grower shipper and direct marketing channels, new technology-driven food marketing companies — virtual food hubs — have evolved to cater to this demographic. They promote the values of sustainable communities, local food economies and business integrity and transparency, all important attributes for new 21st century consumers . These companies form relationships with local growers, provide some technical and market support, and enhance sales and engagement with consumers. It is not yet clear what impacts these still-niche marketing businesses may have on the industry in total. However, growers have responded to the various health and market signals by ramping up production of both conventional and organic products, berries included. Specialists and farm advisors with UC Cooperative Extension have performed economic analyses for Santa Cruz and Monterey county fresh market berry crops for decades . The studies estimate production costs for a representative enterprise based on characteristics common to the area’s farms. Data are collected from established growers, input suppliers and other industry experts so that a diversity of operations and practices are taken into account. Since 1990, UCCE researchers have used a farm budget software program to analyze the data and present results in several formats detailing costs for cultural and harvest practices, monthly cash costs and business and investment overhead costs. The studies also include an analysis estimating net returns to growers for several yield and price scenarios. Representative costs for food safety and environmental quality programs have been incorporated into more recent studies as they have evolved to become standard business practices.

The resulting production and economic information is specifically designed to assist growers, bankers, researchers and government agencies with business and policy decisions. The first economic analysis of fresh market strawberry production for Santa Cruz and Monterey counties was performed in 1969; at least one subsequent analysis has been conducted every decade since then. Though the level of detail and data included in each study has changed over time, some interesting trends can be noted. Annual land rent climbed from $150 per acre in 1969 to $2,700 in 2014, representing 2.5% and 5.5% of total production costs, respectively. The cost of soil fumigation for conventional strawberry production increased from $350 per acre in 1969 to $3,302 in 2010, representing 5.5% and 6.9% of total production costs, respectively. Production year water use gradually decreased from 80 acre-inches per acre in 1969 to 36 acre-inches by 1996 as drip irrigation became the standard. The amount of water used to bring a crop to harvest has remained roughly the same since that time; however, growers and researchers continue to investigate methods to increase water use efficiency even further. In some areas, soil types and fields, growers have been able to reduce per acre water use by several acre-inches more . When the above costs and water usage are assessed on a per ton rather than a per acre basis, production practice cost increases are less notable, and water savings even greater. Labor-intensive practices such as hand weeding and harvest are consistently shown as costly line items relative to other operations. Representative yields for conventionally produced fresh market strawberries rose from 20 tons per acre in the 1969 study to 30 tons in 2010, an increase of 50%. Even higher yields are discussed for some varieties and production conditions; county production statistics confirm that higher yields are indeed possible . Representative yields for organic strawberries, studied over a much shorter time period, raspberry container size rose from 15 tons per acre in 2006 to 17 tons in 2014, an increase of 13%. As more research is directed towards organic agriculture in general and strawberries in particular, yields will likely increase even more with time. Recent efforts include improvements in cultivar breeding, cultural practices and disease management, especially soil pathogen management. The most recent economic analyses for conventional, second year conventional and organic strawberry production were performed in 2010, 2011 and 2014, respectively. Second year conventional strawberries, or those producing a crop for a second year after having produced the first without replanting, represent about 15% of the total strawberry acreage in the area. Similarities and differences in total, cultural and pest management costs for the three management approaches are shown in figures 1 to 3. Total costs for conventional strawberries were $47,882 per acre and include expenses for all practices from land preparation to harvest . For the second year conventional strawberry crop, total costs were lower at $32,798 per acre, reflecting a reduction in expenditures for land preparation and reduced harvest costs because of lower yield.

For organic strawberries, total costs were $49,044 per acre, slightly higher than for conventional production, mostly due to higher soil fertility input costs. Harvest, a labor-intensive practice, clearly represents the lion’s share of total costs, at 58% in organic production, 60% in conventional production and 67% in second year conventional berries. Cultural costs represent 26% of total costs in the conventional and organic systems, but only 15% for second year strawberries because there were no associated planting costs, and because pest management costs were lower . Looking more closely at pest management, soil fumigation is the highest cost category for conventional production at $3,302 per acre, with weed control, another labor-intensive practice, the highest cost in second year and organic strawberries at $1,212 and $2,506 per acre, respectively . However, for organic strawberries the cost to control insects ran a close second at $2,488 per acre, which was dominated by control for lygus bug with a bug vacuum, and two-spotted spider mite with the release of predatory mites. By comparison, estimated costs for insect control in conventional strawberries were lower at $702 per acre and still lower at $579 in second year conventional berries. Raspberry and blackberry production were not routinely studied in years prior to 2003. Since then, several primocane-bearing raspberry and floricane-bearing blackberry cost and return analyses have been performed, with the most recent studies conducted in 2012 and 2013, respectively. Both studies detail establishment and first year production and harvest costs for not-yet-fully-mature crops. For raspberries, first year of production includes a $12,460 per acre construction, management and investment cost for protective tunnels. Costs for a mature raspberry crop are analyzed in the second production year and total $48,210 per acre . For blackberries, costs for a mature crop are shown for the second through fifth production years, and total $43,406 per acre per year. Harvest costs again represent the vast majority of total costs, at 81% and 71% of total costs for raspberries and blackberries, respectively. For raspberries, cultural costs represented a much smaller share of total costs at $4,656 per acre, roughly half of which was for trellis and tunnel management. Blackberry cultural costs totaled $5,709 per acre, of which over half was for pruning and training canes. Each study also includes an analysis of potential net returns to growers above operating, cash and total costs for a range of yields and prices. When evaluating net returns above total costs, gains are shown for higher yield and price points; losses are also documented at many lower yields and prices . Farms with productive soils, experienced managers, optimal production conditions and robust market plans generally realize higher net returns. In contrast, farms with less-than-optimal production conditions, reduced yields, poor fruit quality or inexperienced managers may contribute to lower net returns. Results from the strawberry analyses show that on a per acre basis, organic strawberries tend to be more profitable than conventional berries, even with lower yields. Organic price premiums explain the result; in this example price per tray for organic strawberries ranged from $12 to $18, while price per tray for conventional berries ranged from $7.30 to $11.30. Prices for second year conventional strawberries were slightly lower still to account for a portion of the crop that was diverted to the freezer market. Net returns for both caneberries were mostly positive. Other noteworthy entries in all recent berry studies include per acre costs for pest control advisers , management of invasive pests and food safety and regulatory programs for water and air quality. Though each alone represents a relatively small portion of total costs, they provide readers with insights into the changing nature of berry production activities and costs over time.Cultural practices in the berry industry have evolved to address changes in soil, water and pest management needs.

The alternative hypotheses we present in figure 2 could be addressed with herbarium specimens for plant species with long-term herbarium records and which vary in their phenological sensitivities to climate change. While collections may not always allow us to differentiate between alternative scenarios, they could reveal how herbivory changes with warming for plants across a range of phenological sensitivities, and inform field experiments to tease apart mechanisms. In some cases, it may be possible to test for herbivory by novel herbivores by quantifying types of damage that can be traced back to particular insect genera or species, such as galls and leaf mines , or chewing damage that is characteristic of certain insect orders, e.g. margin feeding, circular hole feeding, and skeletonization. Butterfly collections might also help in resolving alternative scenarios, although we suspect that larvae, responsible for most herbivore damage, may be under-represented in collections compared to adult Lepidoptera, and flight phenology may not be correlated with larval phenology . The mismatch between adult and larval butterfly life histories is a challenge for using butterfly collections to explore phenological asynchronies. However, there are also scenarios in which phenological change at the adult stage may affect herbivory, which may offer opportunities to use the extensive collections of butterflies and moths that are available. For example, some Lepidoptera species may develop ‘lost generations’, raspberry container growing in which warmer temperatures signal caterpillars to develop into adults rather than entering diapause. The adults of the last generation may suffer high mortality rates at the onset of winter; for a more thorough discussion of this topic, see.

Museum specimens of moths and butterflies could inform how common it is for Lepidoptera species to add another generation in response to climate change, and contrasting herbarium specimens of their host plants could reveal how herbivory is differentially impacted by species that have and have not added generations with climate change.One of the most supported predictions in global change biology is that species’ ranges will shift poleward and upward in elevation as the climate warms. For many insect species, poleward range expansion may be explained by increased over-winter survival and/or feeding owing to warmer winters. For multivoltine insects, longer growing seasons can also increase the number of generations completed per year, leading to population growth that might facilitate range expansion if host plants are available. Most predictions on plant species’ range shifts are predicated on the assumption that abiotic factors determine range edges; however, biotic factors can also contribute to range limits. There is also growing evidence that biotic factors, such as herbivores and disease can interact with abiotic factors to determine the trailing range edges of some plant species. However, the factors that drive range limits at leading and trailing edges remain unknown for most species. Biological collections typically have associated metadata describing when and where collections were made, and therefore provide rich data on species distributions and distributional shifts over time. Species distribution models are commonly used to map past and present distributions, but they are intrinsically limited by the number and representation of input records, and, in the case of global change research, the number of records available from before and after global change.

The extensive digitization efforts currently underway for insect and plant specimens will improve our predictions and ability to track changing distributions. For well sampled plant species, we might also be able to investigate changes in herbivory at poleward range edges to determine if it has declined over time as plant ranges expand into novel habitats—an extension of the enemy release hypothesis associated with species invasions, discussed below. Larger digital collections of insect herbivores will provide the opportunity to compare range shifts across insect clades and to identify traits that govern range expansion and contraction. For example, we might expect that warmer winters will disrupt winter diapause for many insect species, leading to range contraction and decline, while those that do not have diapause will benefit from higher rates of winter survival. However, it is also possible that insects with diapause are more likely to maintain phenological synchrony with on how herbivore damage will change over time. Species traits might also determine whether species shift over time or space, and how these two responses trade-off . The ability of insect herbivores to switch host plants may be another factor that constrains or facilitates herbivore range expansion, and thus plant –herbivore interaction strengths. Specialized insects that do not feed on newly encountered plant species may be limited in their geographical spread, whereas more generalist herbivores would be less constrained. Herbaria may capture such switches to novel hosts, showing up as new types of herbivore damage on specimens as host plants and their insect herbivores shift their distributions and provide the opportunity for novel plant –herbivore interactions. For example, leaf mines and galls—which are preserved on herbarium specimens—are made by a wide variety of insect herbivore taxa, including some of the most diverse groups of insects—Lepidoptera, Coleoptera , and Diptera —and are often specific to insect genera or species .

The Lepidoptera that make leaf mines are not well represented in long-term citizen science data because leaf miners are typically micromoths, which are not the focus of long-term observations, and leaf mining and galling damage are only rarely included in herbivory studies, which tend to focus on chewing damage. Thus, herbarium specimens provide a record of a unique insect herbivore fauna not represented in long-term herbivore monitoring or herbivory studies. Herbarium specimens may also provide data on a key hypothesis in global change biology that is based on theory which dates back to Darwin: the role of natural enemy release in species invasions. The enemy release hypothesis describes the escape from native predators and parasites when species are introduced into novel habitats. While there is evidence that introduced plants escape their native herbivores, it is unclear how long this ‘release’ persists. Herbarium specimens can provide rare long-term data on herbivory and disease pressure that allows us to resolve this question. In a well-documented example, Schilthuizen et al. used herbarium specimens to show that the non-native cherry tree, Prunus serotina, acquired higher rates of herbivory over time after its introduction to Europe, while its native congener, Prunus padus, had stable herbivory levels over the same time period. This led to field investigations into the contemporary herbivore communities for these congeners, which revealed that, surprisingly, P. serotina had a richer herbivore community than the native P. padus, and that P. serotina had acquired specialized herbivores from other native host genera. This supports the hypothesis that non-native plants accumulate herbivore taxa over time in their novel habitats, which might have significant implications for plants that shift in their geographical distributions.Urbanization affects insect herbivores via a variety of mechanisms, including habitat fragmentation, habitat and host plant loss, and introduction of novel host plants that attract and support non-native herbivore communities. Given these concurrent pressures, the effects of urbanization on plant – herbivore relationships are complex and varied . However, in recent years, it has become increasingly clear that a key aspect of urbanization, the urban heat island effect, can drive relationships between plants and herbivores and may uniquely inform climate change predictions. The urban heat-island effect—the local warming of urban areas relative to surrounding countryside—increases urban temperatures 1– 128C higher than rural temperatures. Thus, local warming caused by urban development is similar in magnitude to warming expected globally over the next 100þ years, and it has therefore been suggested that cities may provide insights into the future effects of climate change. Like global warming, urban warming drives phenological advance in plants and insect herbivores. For example, plants leaf out and flower earlier in cities than in nearby rural areas, and urban heat is associated with earlier egg production for certain insect herbivore species. While the effects of warming global temperatures on the synchrony of plant –herbivore interactions is still generally unresolved owing to a lack of data, these relationships can be studied across urban temperature gradients, blueberry plant pot and there is some evidence for reduced synchrony between insect herbivores and their natural enemies as a result of urban warming. Because of the parallels between the abiotic and biotic effects of urban and global warming, natural history collections from urban areas may allow us to more broadly predict how global climate warming will affect interactions between plants and their insect herbivores. Phenology data from specimens—e.g. flowering, leaf-out, insect flight— paired with data on urbanization intensity in the areas where specimens were collected could inform predictionson phenological change and synchrony for a broad range of plant and herbivore species. Specimen data from urban areas are, perhaps surprisingly, plentiful. A recent study shows that across three areas with large digitized herbarium collections—the US, South Africa and Australia—plant specimens are often collected close to natural history museums or roads. Thus, specimens could be used to explore urban natural gradients.

Like temperature, urbanization can be easily assigned to historical specimens via contemporary measurements or existing data. As a proxy for urbanization, we can use human population density data from censuses, which many countries have been collecting since the early 1900s, and in some places urbanization can be translated from historical maps or as impervious surface derived from satellite imagery. One novel approach might be to derive markers of urbanization from the herbarium specimens themselves, for example, signature pollutants, although disentangling the contributions of different drivers would then present additional challenges. In recent years, growing evidence shows that urban warming may increase abundance of certain herbivores, notably sapfeeders, potentially leading to more insect damage on urban than on rural plants, a pattern that has been documented by entomologists for over a century. Sapfeeding herbivores, such as scale insects and aphids, are often preserved on leaves and branches and thus may provide insights into changing herbivore pressure in response to urbanization. In a recent study, Youngsteadt et al. counted armoured scale insects on branches of herbarium specimens of red maple Acer rubrum and on branches of live trees across an urban warming gradient. Using these data, they showed that interannual warming and urban warming may have surprisingly congruent effects on scale insect prevalence. In box 2, we discuss how herbarium specimens might be used to investigate more complicated interactions between multiple trophic levels, relationships that could inform biological control efforts and management of urban plants. While the urban heat island effect benefits certain herbivores that survive within the urban matrix by advancing their phenolog and increasing their abundance, urbanization also excludes some insect species—a pattern which has been documented with insect museum specimens—making the effects of urbanization on herbivore damage to plants difficult to predict. Long-term records of butterfly flight from Britain showed that habitat loss is associated with butterfly decline, especially for species that are less mobile and are habitat specialists. Relatedly, a recent study across 16 European cities showed that leaf chewing damage was lower in cities relative to nearby rural areas, perhaps driven in part by higher rates of bird and ant predation on insect herbivores in cities than in rural areas. Thus, a pattern that might be emerging from the literature is that certain sap-feeding insects benefit from urban heat , while leaf chewing and the insects that cause this type of damage, notably Lepidoptera, decline in response to loss of habitat and host plants caused by urbanization. This finding suggests that the effects of bottom-up versus top-down forces driving insect herbivore fitness might differ among feeding guilds . Measurements of broad-scale chewing herbivory , presence of sap-feeders, and incidence of sooty mould as a proxy from herbarium specimens, along with insect herbivore occurrence data, could be used to test this hypothesis . In addition to describing the effects of urbanization at the local scale, museum specimens may also reveal how urbanization affects species distributions at broader spatial scales. For example, while urbanization may disrupt poleward range expansion for some species, it is possible that cities serve as warm habitat stepping stones for species with long-distance dispersal mechanisms, facilitating their poleward expansion. The insects that create leaf mines have been described as ‘aerial plankton’ because they tend to disperse long distances. Herbarium specimens might capture this rapid northern expansion of leaf mining insects and provide a record of shifting interactions with native plants that may be more likely to respond in time than space —see box 1.

A study in natural ecosystems comparing forest and savanna found species richness to be affected by habitat and strata ; the two environments clearly differentiated in terms of their species composition . In our study, canopy vegetation was not a strong driver for the community of twig-nesting ants since our best models did not include a VCI. However, species compositional differences observed across both vegetation layers could be an effect of microhabitat diversity and canopy connectivity . Providing complex vegetation not only promotes ant diversity but also other organisms that facilitate ant colonization into new twigs. Presumably ants often nest in hollow branches of trees that have been previously dwelled or inhabited by beetles . Moreover diversity of trees might also provide nesting resources that are different in terms of how difficult or attractive they are to dig cavities, for example studies have found that tropical woods can be different in terms of their structure, chemistry and biology ; this could suggest important drivers in the differentiation of ants that inhabit them. We found a large number of arboreal twig-nesting ant species in this coffee agroecosystem study supporting the notion that managed ecosystems, such as agroforestry systems in the tropics, blueberries in containers have the potential to host a great diversity of species. A number of previous studies have provided evidence that ant diversity increases control of pests and fungal diseases . We document here that increases in nest entrance size diversity on an individual tree relates to increases in ant diversity on trees. This may thus have important implications for promoting ants as biological control agents in agroforestry systems.

We conclude that the availability of a variety of nesting options and vegetation strata are important drivers of species diversity and support the idea that niche partitioning drives species coexistence . Future studies should further investigate the competitive hierarchies of the species colonizing twigs if we want to understand how species using similar resources interact with each other; and evaluate colony fitness in face of multiple resource use, as has been done in the past for colonies of Cephalotes persimilis . Since ants often engage in interactions that deliver ecosystem services future studies should focus on evaluating roles of different ant combinations using a diverse array of twig entrance sizes in agricultural pest control. Furthermore, we have learned from this study that the structuring of ant communities is multi-factorial and that local as well as regional factors should be considered when explaining species assemblages in the tropics. Habitat complexity is critical for the functioning of ecological communities in both terrestrial and aquatic systems. Processes such as resource foraging, colonization, and species interactions often depend on the level of heterogeneity in the configuration of physical elements in a habitat . Vegetation connectivity and structure are important components of habitat complexity and can influence species interactions and community patterns at local scales. In aquatic systems, more complex habitats made up of macrophytes support communities that are more diverse and abundant, and allow for greater food capture than systems without vegetation . In terrestrial systems, vegetation structure– such as the biomass of foliage and the variety of plant architectures– generally influences species composition, and increases species richness and abundance of numerous taxa . Additionally, vegetation structure can influence mobility and foraging success of vertebrates and invertebrates . In tropical ecosystems, ants are among the most abundant and bio-diverse of taxonomic groups , and are considered important predators, herbivores, and seed dispersers .

Ants are cursorial central-place foragers – organisms that forage from a central place to which they return with food to feed with the colony . Therefore, foraging and discovery of food resources is strongly constrained by the need to construct and follow trails along vegetation . This is particularly relevant for ants using the arboreal stratum as their primary foraging space . For instance, the availability of vegetation connections can maximize ants’ foraging efficiency, locomotion, and velocity , as well as contribute to changes in community composition and species richness . The availability of such resources can ultimately lead to differences in resource utilization by ant communities . In tropical agricultural systems, especially agroforests, ants play important ecological roles , and management practices can strongly influence ant behavior and their potential for providing biological pest control services . Indeed, one of the oldest known records of the use of ants for pest control dates to 304 A.D in citrus plantations in China. In these systems artificial connections made of bamboo were used by farmers to facilitate foraging by the Weaver Ant to suppress damaging phytophagous insects . In that same study, Huang and Yan report anecdotal evidence that suggests equal yields in orchards that use chemicals vs. orchards that use ant bridges to control for pests. Similarly, Peng et al. , report lower levels of fruit damage in cashew with the presence of weaver ants. However, as vegetation complexity declines in agroecosystems, tree density and diversity may also decrease , as well as the possibility to generate connections between the arboreal vegetation, which might impact arthropod populations . The lack of connectivity between trees in managed systems can have a significant impact on the mobility of worker ants and their ability to control resources. This impact may be particularly marked at greater distances from the nest, where ant dominance may be lower . This in turn may influence the ecosystem services provided by ants, particularly the suppression of pest outbreaks .

Shaded coffee plantations, which maintain high levels of shade and structural complexity can sustain complex networks of organisms, which can result in biological pest control . In coffee systems, ants are a functionally diverse and abundant group of ground and arboreal-nesting arthropods and are considered important biological control agents . Ants are predators of the most devastating coffee pest, the coffee berry borer , a beetle that drills cavities in coffee berries and severely damages the seed . Several species of arboreal ants, with nests attached to or inside tree trunks, branches, or twigs, control adult and immature stages of this pest either through direct predation or deterrence . Ants of the genus Azteca are numerically dominant in shaded coffee plantations. These ants forage intensively on coffee plants , and deter CBB adults by removing them from the coffee plant, therefore lowering fruit damage . In shaded coffee plantations, Azteca sericeasur ants nest on shade trees and access adjacent coffee plants through the leaf litter or available pathways, such as fallen branches, vines, and other vegetation , matching the description by Longino for this species in forest habitats. In more intensively managed coffee systems, with fewer and more distant nesting trees, connectivity may be sparse or absent and artificial connections might buffer against this loss. Vegetation structure and arboreal characteristics in coffee plantations are likely to be important factors influencing ant foraging behavior and nesting in arboreal ants . However, the influence of vegetation connectivity on the foraging of this dominant arboreal ant, and its effect on pest removal in coffee plantations has not yet been studied. Previous work has documented the importance of arboreal connections for ants and biological control in agricultural systems. For example, various studies and farmers’ manuals suggest that connecting nests to adjacent trees using bamboo strips enables weaver ants to colonize new trees, which increases ants’ efficiency in removing pests, including the pentatomid insect Tesserarotoma papillosa . However, there is little evidence about the effect of increasing arboreal connectivity on biological control using experimental data. We report an experiment testing the influence of adding connections between shade trees and coffee plants and its effects on CBB removal on coffee plants. To our knowledge, planting blueberries in pots this is the first study providing experimental data on the effect of adding connectivity on ant activity and pest removal in coffee agroecosystems. Specifically, we tested one hypothesis: connectivity affects CBB removal in this system by increasing recruitment rates of A. sericeasur ants to prey items; we predicted that 1) A. sericeasur ants use artificial connections between nesting trees and coffee plants; 2) plants with connectivity have higher ant activity than isolated plants; 3) plants with connections have grater removal rates of CBB by A. sericeasur ants; and 4) A. sericeasur activity and CBB removal rates by A. sericeasur ants decrease with increased distance from A. sericeasur nests. Within the farm, we haphazardly selected 20 non-overlapping sites located at least 10 m away from each other with one Inga micheliana tree containing an A. sericeasur carton nest on the tree trunk .

A. sericeasur is a polydomous, arboreal ant species , which occurs in ~13% of trees at our study site , and forages on coffee plants . Trees were selected only if ant nests were noticeably active. In each site, we quantified ant activity on the nest tree as the number of ants crossing a single point on the main trunk during one minute. This methodology has been used in previous studies to measure overall ant activity of a nest . We then selected the six coffee plants nearest to the nesting tree, making sure they were not directly touching each other or the tree by removing branches and vines . We then randomly assigned three of the coffee plants at each site to aconnection treatment and three as controls without connections, then measured ant activity on the plants by counting the number of ants passing a point on the central trunk for one minute. We connected treatment coffee plants to the nesting tree using jute string . Strings remained in the field for three days to allow for ant acclimation to disturbance and for ants to establish new foraging pathways. After three days, we returned to the sites and remeasured ant activity on the nesting tree and coffee plants. Observations took place between 10 am and 1 pm, and were immediately stopped as soon as it started raining, as this drastically decreases ant activity.To test how connectivity impacts potential biological control provided by ants, we added dead adult CBB onto connected and control coffee plants to directly assess ant removal rates. We collected CBB infested coffee berries from the field, dissected them, extracted female adult CBB individuals , and placed them in the freezer for up to 24 h, after which beetles were dead. Three days after placing strings and after reassessing ant activity, we placed 10 dead CBB adults on a small piece of white card on each coffee plant near the center of the trunk, left cards for 30 min, and then counted the number of CBB remaining. Restricting movement of sentinel prey, either by gluing them to observation sites or freezing them is a common technique for assessing predator behavior . We used frozen sentinel prey to increase the availability and similarity of beetles on cards and to reduce the potential for live prey to escape from the arena. To assess whether CBB removal was due to ant activity, we monitored cards across the plot over a period of 30 minutes and recorded any arthropods present. Only ants were observed on the cards, indicating that these were responsible for removing the CBB. Although we acknowledge that the use of dead prey may alter ant behavior, it is already well established that A. sericeasur both antagonizes and predates live CBB in the field, and reduces CBB infestation on plants . We used dead prey in this experiment to more readily assess ant removal rates and infer that these changes translate to changes in the bio-control efficiency of this ant on live prey. Immediately following each experiment, we characterized the vegetation in each site because several different environmental factors are known to influence ant foraging in coffee systems . We measured the percentage of canopy cover , coffee plant height, and distance from each coffee plant to the central Inga nest-tree.To test for statistical differences in ant activity on coffee plants before and after establishing connections we used a GLMM. We included time , treatment , coffee plant distance to nest tree, the interaction between time and treatment, and the interaction between time and distance as fixed effects . We also included coffee plant height and ant activity on nest tree as covariates.

While C0 wines in this study demonstrated lower alcohol content than shaded wines, previous literature corroborates cluster temperature reduction by partial solar radiation exclusion as an effective method to lessen sugar content in the grape berry and thus reduce alcohol content of wines . The effect of partial solar radiation exclusion in semi-arid climates on berry pH and TA is mixed. Previous work demonstrates partial solar radiation exclusion to reduce pH and increase TA in grape berries by reducing the thermal degradation of organic acids . However, in the present study, berry pH and TA at harvest were unaffected in either year by shade films . Nonetheless, there were apparent effects on wine pH and TA that were vintage dependent. In the present study, D3 wines had the lowest pH and highest TA, while C0 wines did not differ from the shade films D1, D4 or D5 in pH or TA in 2020. Differences observed in pH between the wines ultimately affect the colorimetric properties of these wines. In 2021, D4 and D5 wines showed the highest pH values. It is understood that the pH of the wines can shift the anthocyanin equilibrium in wine solution between the flavylium and quinoidal base forms . In the present study, D4 wines had the highest pH and the highest CI. In many cases, when pH rises, CI will decline as anthocyanin equilibrium shifts away from the flavylium form towards the colorless quinoidal forms . However, large plastic pots this was not the case in the present study. Rather, improved color intensity at elevated wine pH could be attributed to co-pigmentation in the wine matrix.

Co-pigmentation refers to non-covalent interactions between anthocyanins and cofactors such as flavonols, flavan-3-ols and proanthocyaninidins, that results in greater absorbance of the wine than color what would be indicated by anthocyanin content and pH conditions . Copigmentation in young wines was shown to increase color intensity in young red wines . In the hotter 2020 vintage, the total flavonols in grape berries were increased in D4 fruit compared to other treatments . This increased berry flavonol content was transmissible during winemaking, as D4 wines also showed the highest total flavonols with similar concentrations as C0 wines in 2020. TPI was also enhanced in D4 wines. As such, this increased the abundance of cofactors in the wine matrix. Thus, improved color intensity documented in D4 wines in both vintages could be due to the enhancement of absorbance from increased flavonol content by reducing thermal degradation in the vineyard . In the cooler 2021 growing season, shade films produced wines with less flavonols than C0, but greater anthocyanin content, thus leading to improved color intensity in D4 wines. The increase of phenolic cofactors in D4 wines not only enhanced color and hue, but also led to a higher percentage of polymeric anthocyanins when compared to other shade treatments. Phenolic and polyphenolic compounds from grape skins and seeds can form polymeric pigments in wine with anthocyanins. These polymeric anthocyanins are more stable than monomeric anthocyanins and help to stabilize wine color. This occurs as the proportion of monomeric anthocyanins decreases, leaving color to be maintained by polymeric anthocyanins . Across both vintages, the percentage of polymeric anthocyanins was maximized in D4 wines, indicating that these wines may have greater aging potential than wines from C0 and other shading treatments.In the present study, partial solar radiation exclusion modified the composition of anthocyanins in wine. Partial solar radiation exclusion resulted in increased anthocyanin glycosides in wine from shade film treatments except for D4 wines in 2020.

In 2021, D4 consistently showed the lowest cluster temperatures post-veraison and as a result, demonstrated the highest concentration of glucosides in resultant wines. Excessive berry temperatures post-veraison in both vintages led to C0 fruit with reduced total anthocyanin content at harvest and this carried over into resultant wines . The reduction of near-infrared radiation by at least 15% produced a cluster temperature conducive to anthocyanin accumulation, as these compounds are susceptible to thermal degradation above 35°C . When comparing total anthocyanin and flavonol concentrations between 2020 and 2021, regardless of treatment, 2020 wines had anthocyanin and flavonol concentrations six to seven times less than those in 2021 wines. As flavonoids are susceptible to thermal degradation, this drastic difference in total flavonoid concentrations may be attributed to hotter vintage air temperatures in 2020 compared to 2021. Previous works show berry sunlight exposure to alter the composition of anthocyanins, such as the proportion of acetylated and coumarylated forms . Modulation of acylated, methylated, and hydroxylated forms of anthocyanins result from the synergistic effect of solar radiation exposure and the coupled increases in berry temperature . Generally, high berry temperatures resulting from increased solar exposure results in increased acylated anthocyanins in the grape berry, particularly coumarylated forms . Also, high temperatures result in accumulation of highly methylated anthocyanins such as malvidin derivatives, as these compounds are less likely to degrade than their counterparts . In 2020, D1 and D5 wines demonstrated highest concentrations of acetylates, coumarylates, and methylated anthocyanins compared to C0 wines. While D1 and D5 treatments demonstrated cluster temperatures less than those from C0 treatments , the concomitant thermal degradation of total anthocyanins in C0 treatments proved to negate any modulation towards acylated or methylated forms in resultant wines.

Similarly in 2021, C0, D1 and D5 wines exhibited reduced acylation compared to D4 wines. Again, while D4 consistently exhibited less intense cluster temperatures, the thermal degradation in more exposed treatments eclipsed any identifiable acylation modulation from hot growing conditions. Acylated anthocyanins are more stable compounds and provide color stability and increase blueness in wine . However, an increase in methylated anthocyanins will lead to redder hues in wine . Therefore, the improvement in acylated and methylated anthocyanin content due to partial solar radiation exclusion may enhance color perception in young red wines through color stabilization and alteration of wine hue. Likewise, anthocyanin hydroxylation is also directly influenced by temperature and solar radiation exposure. Previous studies on berry exposure utilizing UV selective shade nets as well as leaf removal, demonstrated anthocyanin tri-hydroxylation increases with increasing berry temperature . Increases in tri-hydroxylation are driven by accumulation of malvidin derivatives and the temperature sensitivity of F3’H, the catalyzing enzyme for 3’- hydroxylated anthocyanin biosynthesis . The highest ratio of tri- to di-hydroxylated anthocyanins in 2020 C0 wines were driven by higher concentrations of 3-p-coumaroyl-glucoside derivatives of delphinidin, petunidin and malvidin, despite the ratio of tri- to di-hydroxylated anthocyanins being unaffected at harvest in the grape berry in 2020 . Among shade film treatments in 2020, the reduction of UV light exposure, was the determining factor in anthocyanin hydroxylation patterns rather than berry temperature. Previous shade net studies at the experimental site showed a reduction in UV radiation with black-40% and blue-40% shade nets led to higher anthocyanin tri-hydroxylation in the grape berry compared to control vines at harvest . With the reduction of UVB and UVC radiation in D4 and D5 vines, anthocyanin tri-hydroxylation was reduced, regardless of temperature. Ultimately, the upregulation of F3’H from sun exposure could be negated by the reduced catalytic activity of this enzyme under high temperatures experienced in 2020. In the cooler 2021 vintage, the ratio of tri- to di-hydroxylated anthocyanins was unaffected, due to non-significant effect of shade films on acetylated anthocyanins. Ultimately, increased tri-hydroxylation in young red wines will also impact wine hue, resulting in more purple wines . Flavonols in the grape berry skin act as photoprotectants and are strongly induced by ultraviolet radiation . Flavonol composition in the grape berry can be used to determine overexposure, raspberry container specifically by quantifying the molar abundance of kaempferol. C0 berries in this study were shown to be overexposed by surpassing the previously described threshold of approximately 7% molar abundance of kaempferol . In both years of the study, flavonol composition in grape berries was maximized in C0 fruit, but D4 and D5 fruit contained the most flavonols across the shade films with minimal thermal degradation of the compounds on the vine. Likewise in both winevintages, flavonol concentration was modulated by UV radiation exposure, proportional to the amount of UV radiation transmitted to the grapevine. Of the wines produced from shade films treatments, D4 allowed for the most UV transmission while subsequently reducing near infrared transmission by approximately 15%. These light conditions ultimately optimized flavonol content in D4 wines compared to the other shade treatments from both wine vintages. As such, this demonstrated the transmissibility of berry composition under shade treatments to directly improve wine flavonoid profiles. For hot viticulture regions, photo selective solar radiation exclusion provides a strategy to improve not only flavonoid profile but also wine color intensity through copigmentation with anthocyanins.

C6-alcohols such as 1-hexanol and -2-hexen-1-ol are often found in wines as fermentation products. These compounds are derived from microbial mediated cleavage of the C-C double bonds in linoleic and linolenic acids, by lipoxygenase and alcohol dehydrogenate enzymes in yeast . Compounds such as 1-hexanol and -2-hexen-1-ol are associated with aromas such as cut grass, green, fat, and herbaceous aromas and their OAV thresholds are 8000 and 400 ug/L, respectively . The effect of shade films on C6-alcohols was evident in both years; however, there was a yearly effect on which alcohol was altered by the treatment. In 2020, -2- hexen-1-ol was the lowest in D4. In 2021, -2-hexen-1-ol was unaffected by shade films, while 1-hexanol was highest in C0, D4 and D5. Although there was a statistical difference in C6 alcohols, the differences were not large enough between C0 and treatments to cross the OAV thresholds for these compounds. Increases of C6-alcohols in C0, D4, and D5 wines may be explained by solar radiation overexposure in the treated clusters. L. He etal. reported higher linoleic and linolenic acid biosynthesis with leaf removal at veraison. Subsequently, fruit exposed to increased solar radiation had elevated precursors for C6-alcohol production during yeast metabolism. Additionally, L. He et. al. showed higher initial concentration of C6-alcohols in grape berries from leaf removal treatments due to modulation of the volatile compound metabolome and transcriptome in grape berries exposed to sunlight under dry-hot conditions. Therefore, in our experiment which has similar climatic conditions to L. He et. al. , fruit from shade films with higher percentages of UV radiation may have both an increase in linoleic and linolenic acids to act as C6-alcohols aromas precursors and increased C6- alcohols in the exposed grape berries. Ultimately, overexposure of the grape berry led to more green and grassy aromas in wine, which may lead to an unripe perception of these wines. These compounds are generally pleasant aromas including mushroom, roses, honey, candy, and fruity notes. Of these compounds, shade treatments increased isoamyl alcohol concentration in 2020 and benzyl alcohol concentration in wines from both vintages. Isoamyl alcohol is associated with solvent and cheese aromas and, while benzyl alcohol is characterized as being citrusy and sweet . The odor active thresholds for these compounds are 30000 μg/L and 10000 μg/L, respectively . In 2020, C0 had the lowest concentration of isoamyl alcohol in wines. The effect of shading on the concentration of isoamyl alcohol in wines varies in literature . In hot growing regions, 75% of total solar radiation exclusion with black polyethylene canopy side shade nets resulted in wines with reduced isoamyl alcohol compared to the uncovered control vines . However, this experimental site was in a region that received approximately 704.5°C less growing degree days than the present experimental site in the hotter 2020 season, and 514.1°C growing degree days less than the cooler 2021 season. In the study by Lu et al. 2021, reduced solar radiation exposure in a cooler growing region may have resulted in reduced isoamyl alcohol in shaded fruit. When cluster temperatures exceed 42°C in exposed vines, there is a reduction in isoamyl alcohol in resultant wines compared to wines produced from fruit under red and black shade nets . With cluster temperatures of C0 fruit exceeding 42°C, excessive cluster temperatures may be prompting the reduction in isoamyl alcohol and overall wine fruitiness from those produced from overexposed clusters. However, while there was a statistical difference in isoamyl alcohol concentrations between C0 and treatment wines, the effect was not large enough to exceed the OAV threshold for this compound . Shade films affected the ester composition predominantly in 2020 wines.

The data from the Napping test were digitized by writing in a table, for each product, its X-coordinate and its Y-coordinate on the sheet. The origin was placed on the left bottom corner of the sheet.The chemical and sensory data of the wines were analyzed by multivariate analysis of variance , with the factors as the wines and replicates, and frequency distributions were analyzed by the Chi-square test; all statistical analyses were completed using Statgraphics Centurion . Principal component analysis was performed using XLSTAT v. 2018.3 ; partial least square regression analysis was performed using Unscrambler . A multiple factor analysis in which each subject of the Napping® panel constitutes a group of two un-standardized variables was performed using XLSTAT. The typicality scores of the second table and the Color scores of the third table were considered as two sets of 11 + 11 supplementary variables: They do not intervene in the axes construction, but their correlation coefficients with the factors of MFA are calculated and represented as in a usual PCA. Descriptive Analysis data were analyzed by MANOVA, to check overall differences among the products for aroma, taste, and mouthfeel terms. Following a three-way ANOVA with the factors wine, judge, and replicate as well as their two-way interactions, Fisher’s LSD test was used to detect differences among wines for the separate attributes. In those cases, where the effect of the wine was significant, but one of the interaction terms included wine as a factor, a pseudo-mixed model was applied. Here, a new F-value was calculated with the mean sum of squares from the significant interaction as an error term for the factor wine. The significance level for all statistical tests was set to p < 0.05. The chemical eligibility profile of the wines was represented by the standard chemical parameters , color indices and polyphenol composition.

The chemical data were elaborated using the PCA, growing blueberries and the results were reported in Figure 1a,b. Figure 1a shows the observations on a two-dimensional map. Figure 1b shows the correlationcircle and the projections of the initial variables in the factors space. The first two dimensions accounted for 57.90% of the total variance. The first dimension separated the wines between Italy and California based largely on the polyphenol composition. According to the squared cosines of the variables for the two dimensions, it was possible to determine that on the first dimension , quercetin , gallic acid , myricetin , total phenols index , color intensity , polymeric phenols , hue , residual sugar , volatile acidity , and pH were the variables well linked to this axis. On the second dimension , samples were separated by anthocyanin , delfinidin-3-O-glucoside , peonidin-3-O-glucoside , malvidin-3-O-glucoside, and quercetin-3-O-galactoside composition . According to the importance of the above mentioned variables, the Italian wines on the right side of the plot were characterized by the polymeric phenols, monomeric anthocyanins , color intensity, and total phenols index. The Californian wines on the left side of the plot were instead characterized by hue, residual sugar, pH, volatile acidity, malvidin-3-O-glucoside, and quercetin. The two ellipses defined the interval of confidence and helped to evidence a better separation between wines in the two regions. The chemical identity profile of the Sangiovese wines was represented by the volatile compounds originating in the grape and by the alcoholic and malolactic fermentations . The data were elaborated using the PCA, and the results were reported in Figure 2a,b. Figure 2a shows the observations on a two-dimensional map. According to the squared cosines for the variables on the two axes , the volatiles that were well linked to the first dimension were ethyl octanoate , octanoic acid , ethyl butanoate , ethyl decanoate , isoamyl acetate , 4-terpineol , and β-phenylethanol , while compounds on the second dimension were β-phenethyl acetate , TDN , 3-methylbutan-1-ol , isoamylbutanoate , and β-damascenone . Wines were separated according to the region of origin along the first dimension. In particular, most of the Californian wines were located on the right side of the plot described by volatile compounds such as esters , acetates and fatty acids .

On the left side of the plot, the Italian wines were characterized mostly by varietal volatile compounds such as terpenes β-citronellol, β-linalool, 4-terpineol, α-terpineol and norisoprenoids . However, the wines from the two different origins were not completely separated by the identity profile as evidenced by the overlapping confidence intervals of the two ellipses . Using Descriptive Analysis, the panel of trained judges described the sensory attributes of the Italian and Californian wines. Figure 3a,b shows the distribution of the wines according to the sensory eligibility and identity descriptors . Only significant descriptors were used for the PCA, and 79.30% of the total variance was explained by the first two factors/dimensions. One of the main objectives of this study was to examine intrinsic quality of the samples, evaluating how chemical differences in wines from Italy and California, in terms of eligibility and identity profiles , could reflect on the sensory perception of wines. In this context, the chemical eligibility profile of the wines was represented by the standard chemical parameters , color indices and polyphenols composition, while the chemical identity profile was represented by the volatile compounds originating in the grape and by the alcoholic and malolactic fermentations . The experimental data showed that the Sangiovese wines from Italy and California resulted in differences mostly for chemical eligibility profile. In particular, it was very evident that the Italian and Californian wines differed in their color indices and polyphenol composition . In fact, the Italian wines were higher in polyphenols compounds and in color intensity. These results were in agreement with the chemical characterization of Sangiovese wines from Italy and California for the 2016 harvest where the Italian wines resulted in higher color intensity and total phenols index compared to the Californian ones, that showed instead a higher hue. The values for these indices were consistent with other findings for Sangiovese wines. The differences in color indices were better explained by the polyphenols compounds of the wines that resulted in higher amounts for the Italian wines. They showed higher amounts of pigmented polymers and monomer anthocyanins . Sangiovese red grape is considered a variety with a neutral aroma since the total amount of terpenes is lower than 1 mg/L, and this variety is not dependent upon monoterpenes for its varietal flavor. In the Sangiovese pulp and skin some norisoprenoids precursors such as TDN, riesling acetale, damascenone, and vitispirane are detected. The above varietal volatile compounds were determined in both Italian and Californian wines indicating that the varietal aspects of the Sangiovese grape were maintained in both regions. Important differences were instead evidenced in wines from both regions according to the fermentative volatile compounds. The Californian wines were richer in the composition of these fermentative volatiles than the Italian wines confirming the trend observed for the same regions for the 2016 vintage. Significant differences for volatiles between the two regions were reported in Table S2 as supplementary material.

Based on the chemical differences in the composition of the wines from the two regions, we further explore how intrinsic quality, in terms of chemical differences, could be reflected on eligibility and identity sensory profiles of the wines. Moving to the perceived quality, square plant pots the second target of the study was to see how Tuscan wine experts perceived the peculiarity/typicality of the Sangiovese wines from Italy and California and to link the sensory descriptors that might be associated with the wines’ typicality. The sensory profiles of Californian and Italian samples were separated from each other, and the analysis of the correlation with the descriptive attributes allows interpreting this separation in terms of differences of both eligibility and identity profiles. The Californian samples were correlated to the identity attributes Bell Pepper, Cherry, Red Berries, Citrus, Honey. The attributes Barnyard, Earthy and Rubber were correlated to 4I and 5I wines, while there was not any correlation with the Californian wines. Given that all the samples were checked for the defects before all the sensory tests, this contrast seemed to describe a freshness range, for which varietal aromas were perceivable in some samples , while in other they were hidden by some typical aromas of a full-developed wine . The eligibility profile underlines this separation, with the samples on the left side of Figure 3a correlated to Sweetness that, even if associated to Alcohol and Burning/Hot, elicits a softer sensation respect to the Astringency and Sour of the Italian ones on the right side. The perceived quality was studied by the Napping and typicality test. The Napping test results showed that the Californian and Italian wines were clearly separated, evidencing that the two kind of wines were perceived differently for the gustative and olfactive characteristics. Despite of that, the results of the typicality evaluation did not show the same clear discrimination between the wines from the two regions: The average score of all the wines were very similar with the Californian wines slightly higher but not significantly different . Figure 4 showed the correlation between the distribution of the wine samples according to Napping X- and Y-coordinates: the subjects were positioned in the second, third and fourth quadrants of the graphic with a concentration of the higher scores in correspondence of the position of two Californian samples and one Italian . This result can be explained by the fact that, even if the expert subjects perceived differences among the wines, they did not associate them uniquely to typicality. Given the extensive training and experience of the experts, the lack of agreement among them can be interpreted not only as a variability of their opinion but also as an indication that from the point of view of perceived quality in terms of typicality of the Sangiovese wine, the experts viewed all of the wines as falling within the identity profile. At the same time, the distribution of the higher average scores denotes that typicality has been correlated to fruity and floral attributes, in opposition to Bell pepper, Barnyard, Rubber, and Earthy descriptors. In other words, the typicality of Sangiovese has been connected to the perception of the varietal characteristics that in this wine were related overall to fruity and secondly to floral.These findings were evidenced by the PLS prediction of the typicality by the identity sensory attributes such as Cherry and Red Berries. In the case of color evaluation, the experts more clearly separated the wines and overall the Italian wines had significantly higher scores. In fact, these samples, reflecting the chemical parameters, had a more intense color and overall a lower hue compared to the Californian ones. These results showed that the Sangiovese variety is recognizable even if grown abroad, very far from the original terroir of Italy and in particular in Tuscany. This is supported by the fact that the varietal volatiles were found in both wines from both countries, even if the Californian wines were more intense in fermentative volatiles than Italian wines were. Despite this, the main differences seemed related more to the intrinsic quality in terms of eligibility chemical and sensory profiles. Important and significant differences were found in wines for the polyphenol composition since Italian wines were higher in color intensity, tannins, monomeric anthocyanins, and pigmented polymers content. Consequently, they were perceived more intense in color and astringency. On the other hand, Californian wines were higher in alcohol content and pH and lower in titratable acidity compared to the Italian wines. These results reflected the eligibility sensorial perception of the wines in which the Italian wines tend to be more acidic, less sweet, and more astringent than their Californian counterparts. These results evidenced that the terroir seemed to influence the eligibility characteristics of the Sangiovese grape variety, in particular for the polyphenol composition. In Italy, wines with a designation of origin are subject to production requirements that dictate many aspects of wine production such as the maximum grape yields, alcohol level, irrigation, and other quality factors, before an appellation name may legally appear on a wine bottle label. In general, the US has the highest national average yields, at 6.5 tons/acre , and the only requirement to use the AVA name on the wine label is that 85% of the wine must have come from grapes grown within the geographical AVA boundaries.

The same miRNA candidate was described in the grape miRNA atlas also predicted to target several genes of DFR-like and one CCR. As for known miRNAs, several members of the miR395 family are differentially expressed at 19 ◦Brix and at harvest in Bolgheri and in both Bolgheri and Riccione, respectively, when comparing the two cultivars. Moreover, miR395f is differentially expressed also in CS at harvest between Montalcino and Bolgheri. This miRNA has been shown to target genes involved in Sulphate assimilation and metabolism , and hence it could be connected to flavonoid and stilbene pathways as suggested by Tavares et al. . miR399 family members are also differentially expressed in several comparisons: at 19 ◦Brix between Riccione and Bolgheri in CS and between Riccione and Montalcino in SG, plus in Montalcino between CS and SG. At harvest, miR399 are differentially expressed in SG in all the three comparisons among vineyards and in Riccione between CS and SG. miR399 is implicated in Phosphate homeostasis being rapidly up-regulated upon Pi starvation . miR399 regulatory network has been shown to be important in flowering time and was identified as a temperature-sensitive miRNA , however its characterization in fruit ripening is lacking, although intriguing. miR396 family members are known to be regulated during organ development, targeting Growth Regulating Factors and also in berry development , and we observed their modulation during berry ripening in our data as well, but more interestingly, drainage planter pot they are also differentially expressed between CS and SG in berries sampled in Bolgheri at 19 ◦Brix.

Finally, the investigation of the global relationships of different small RNA classes and miRNAs expressed in different grapevine cultivars, collected in different vineyards and developmental stages, suggests that although the vineyard may influence their profile of abundance it probably does in less proportion than developmental stage and cultivar. Somehow, this behavior would be expected because although the epigenetic state is dynamic and responsive to both developmental and environmental signals, small RNAs in general and even more miRNAs are well known to play numerous crucial roles at each major stage of plants development . The results here described are in agreement with those reported in the grapevine miRNA atlas , especially with respect to the clustering of berries according to their developmental stage, sustaining the idea that miRNAs influence organ identity and clearly separate green and ripened berries. Also, in the study of the grapevine transcriptome performed by Dal Santo et al. , they observed that other factors such as year and developmental stage had more influence on the gene expression, rather than the environment. Garden or English peas are hardy, cool season, vining annuals grown for their fresh immature green seeds and pods. Peas are classified in the Fabaceae family, which consists of approximately seven hundred genera and seventeen thousand species, with cosmopolitan distribution throughout the temperate, subtropical, and tropical zones of the world. Many species in this family are used as food, forage, timber, and dye plants. Peas are thought to have originated on the eastern rim of the Mediterranean into the mideast. Remains of 7,000- year-old carbonized seeds have been found in Switzerland. By the height of the Greek and Roman civilizations, peas were well established garden, field, and green manure crops. Although peas are not heavy yielders , they are well worth the effort in small gardens. A fresh garden pea’s taste is so far superior to its store-bought equivalent that it is in fact a different vegetable—sugar vs. starch, fresh and lively vs. dull and soggy. Along with spinach, peas usually herald the first working of the soil and planting in spring. If all goes well, sweetness and succulence await you 50 to 70 days after planting seeds. Because they need to be trellised, peas afford excellent opportunities for intercropping .

Once established, peas don’t require much work. They are able to grab onto the trellis and spread themselves out for greater exposed photosynthetic area and better air circulation to reduce the incidence of mildew. They are not very sensitive to weed pressure. In fact, weeding established pea patches can do more harm than good, as peas have numerous surface roots that are sensitive to disturbance.Cultivation. All peas are emphatically cool season crops. Optimally, they are direct sown when the soil temperature averages over 50° F. Sixty to eighty days of temperatures below 80° F are requisite for good production. Soil temperatures of 55°–75° F will yield germinating seedlings in 7–10 days. Overly wet and cold or wet and warm soil increases the percentage of pre-emergent rot. In fact, because pea seeds are large and can imbibe and hold so much water, allowing the soil to dry down significantly between waterings will reduce rot and ensure good germination. Soils. Good drainage is essential for vigorous growth. Early cropping favors sandy soils as they drain and warm more quickly than clays. Peas, as do most legumes, prefer a slightly acid to slightly alkaline soil pH. This higher pH range also provides for the high calcium needs of peas. Peas are intolerant of acid soils. Planting. Peas should be direct seeded or gently transplanted from speedling/plug trays. Seeds can either be drilled in rows or broadcast sown. Drills can be single or double rows 2–4 inches from the trellis to facilitate the tendrils finding the fence. Seeds should be sown heavily , as pea seeds generally have a moderate germination percentage even under ideal conditions. Thin to 8–12 seeds per foot if necessary. The general adage about covering seed two to three times its narrowest diameter applies here; seeds should be planted 1–1 1/2 inches deep, then gently tamped or watered in.

Pea seeds can also be thickly broadcast at 2–3 seeds per square inch, and raked in or covered with soil. Twiggy brush or one to two layers of horizontal netting creates the trellis for support. This broadcast method nets a higher yield per area but can increase incidence of powdery mildew due to restricted air circulation. Note that pea seed viability is relatively short under ideal circumstances. In most home garden situations seed will only last 1–3 years. When ordering pea seeds, think in 1/2 and 1 pound increments . Varietal selection is important as to plant height and time to maturation, but most importantly, pay attention to disease resistance. Basically, if a varietal description doesn’t tout or mention disease resistance, be a smart shopper and realize it probably has none. The more recent the varietal introduction, the more disease resistant it is. Unfortunately, the converse is true as regards heirloom varieties. Nutrients. Because legumes are capable of fixing nitrogen via association with soil bacteria, garden peas are mistakenly thought to need little or no supplemental nitrogen. The truth is that they fix very little nitrogen unless inoculated with the appropriate species of bacterium . They will also use most of the nitrogen they fix and thus don’t particularly enrich the soil for the following crop. Phosphorous is an important nutrient for early root development and to assist with flowering, fruiting and sugar development. Fortunately legumes are efficient at gathering and concentrating phosphorous. Fertilizing the peas prior to planting is optional on enriched or improved soils. A compost of chicken manure, mixed greens, and straw or leaves will boost nitrogen and phosphorous levels. Composts of brassicas and legumes will concentrate phosphorous and calcium. With a single or double row of peas on a trellis in the center of a 48-50-inch-wide raised bed, plant pot with drainage a crop of quick-maturing plants can be grown along the bed edges for more efficient use of space. These include — Planting Days to Crop method harvest baby spinach direct sown 20-30 days mature spinach direct sown 40-50 days cutting lettuces transplanted 20-30 day mature leaf or transplanted 40-50 days mini romaine lettuce butter lettuce transplanted 50-60 days arugula direct sown 20-30 days direct-seeded radishes direct sown 30-40 days Inoculation. Pea plant vigor and thus production is markedly increased when the seed is inoculated with the appropriate species of Rhizobium bacteria . These bacteria can be purchased in a powdered carrying agent from most seed catalogues and nurseries. To inoculate, simply dampen the seed, add powdered inoculate and mix until the seeds have a blackened, peppered look. Plant as soon as possible as the water activates the bacterial population and desiccation is harmful. Watering. Peas require 1–2 inches of water per week. They are intolerant of water stress ; stress will reduce plant size, decrease yield quality—resulting in tough, starchy peas—and severely shorten the length of cropping. Flowering and early fruit set are key times to ensure an even flow of water. While peas have a tap root that can penetrate up to 3 feet, most of the effective feeding roots range from just under the surface to 12–15 inches deep.

Once peas are established, and especially as they begin fruiting, they are subject to a fungal disease called powdery mildew. Overhead watering in conjunction with high humidity will bring on the disease. To help avoid the problem, either water overhead in the morning prior to a sunny stretch of weather so that the plants will dry out, or use drip tape or soaker hose around the base of the plants. Trellis or Fencing. All but the shortest varieties of peas need some sort of support. Although many varieties are advertised as self-supporting , this is not true. Fencing allows closer plant spacing , because the plants can spread out on the trellis or fence. Fencing also increases sunlight interception, minimizes disease, and facilitates easier picking. One age-old tradition for trellising peas is what the British refer to as “twiggy brush.” The branched prunings of last year’s growth from fruit trees inserted into the soil make an excellent, cheap, and somewhat artistic fence. The brush is usually good for two to three years. One- and two-inch chicken wire will also suffice. Unlike beans, peas aren’t a heavy plant or fruit, thus they don’t need as strong a fence. In fact, garden twine run vertically or woven between horizontal 2x4s makes a biodegradable/compostable trellis. String on a wooden A-frame also works. The important thing is to install the trellis prior to planting and to rotate it around the garden so as not to be tempted to repeat the crop in the same bed before two to three years have passed. Crop Establishment. Unless peas are ridiculously oversown, thinning is unnecessary. Spacing plants farther than 3–4 inches apart makes no sense, nor increases yield per foot. One weeding at the 3-inch stage usually keeps the peas ahead of the weeds. Because peas are so succulent, the less the crop is handled the less the physical damage. Even micro-breaks in the foliage can lead to an “invasion” of powdery mildew. Mulch. Mulching helps protect the surface roots from heat and desiccation, thus prolonging cropping as summer approaches. Harvesting. This is usually not a problem on a garden scale. To avoid harming the plants as you pick, hold the stem in one hand and pinch the pod off the vine just behind the calyx with the other hand.As the worldwide obesity epidemic continues to grow, the prevalence of type II diabetes is also rising to a projected 439 million of individuals globally by 2030. Of all obesity-related chronic conditions, diabetes is most strongly associated because of their similar symptomatic manifestations. Type II diabetes and obesity are both characterized by insulin resistance, glucose intolerance, hypoadiponectinemia, endoplasmic reticulum stress, and low-grade inflammation. Over 11% of the 34% of U.S. obese adults are reported to be diabetic in 2011.2 Obesity is generally thought to stem from a combination of genetic and environmental factors. Increased dietary consumption of fat and refined carbohydrates along with decreased physical activity contributes to excessive weight gain while underlying genetic dispositions may lead to differential clinical progression. It has become clear that modest weight reduction can improve glycemic control and alleviate insulin resistance as obesity is considered a modifiable risk factor for diabetes. Furthermore, the comorbidity of diabetes and obesity has been linked to liver and colon cancer risk, although the precise mechanisms remain unresolved.

An anticipated management solution to phenological shifts is planting later ripening and stress tolerant alternative varieties. Government response to climate change will determine the actions European growers are allowed to take to adapt to climate change, considering the current trials of alternative varieties planted in small diversity blocks in France as a positive example . Ancient varieties being tested in temperature gradient greenhouses in Spain for response to combination stresses of drought, heat, and elevated CO2 showed greater resiliency to stress and did not shift phenological timing, although this was a short-term experiment . In some cases, alternative varieties may be hybrid crosses between existing cultivars and later ripening varieties. However, hypothetical crosses between very late ripening varieties were modelled and still struggle to be late-ripening enough to endure the predicted 23-day shift and potential increase of 7°C expected by the end of this century for major wine grape growing areas . Alternative varieties can be identified by oenological and ecological principals that make them suitable candidates for replacing existing cultivars, such as flavor profile and ability to survive long term through stressful climate change conditions . The challenge of adapting new varieties is highlighted by current popular varieties struggling with increases in growing season temperatures , drainage collection pot however a combination of diversity block trials and greenhouse experiments will guide predictions of the best alternatives .

Our present knowledge of grapevine climate niches is limited relative to the vast diversity of cultivars . With California as an example, there are many potential late ripening varieties suitable as alternatives to early ripening Chardonnay that have yet to be tested in diversity blocks . Even clones can have a varied response to climate change variables . Varieties with heat and drought tolerance traits are a starting point for elevated CO2 studies, as we expand from understanding the mechanisms of change into exploring mitigation strategies. Exploring the vast diversity of grapevine using diversity plots is a straightforward ecological approach, which could be enhanced by evaluating the success of plants under several biotic and abiotic stresses predicted for the future. Many studies on the impacts of leaf removal suggest that manipulating canopy cover is an effective way to mitigate phenological shifts caused by climate change . Leaf removal at pre-bloom positively influences cell division in inflorescence, by reducing sugar transport and decreasing flower fertility, which mitigates cluster compactness . Not only can leaf removal aid in delaying phenology, but other positive impacts also include increasing acid to sugar ratio at harvest, increasing production of anthocyanins and flavonoids, and decreasing incidence of bunch rot disease . Ecologists generally study a system’s responses and interactions, and viticulturists need this system perspective for the challenges presented by climate change. Our understanding of the effects of elevated CO2 on the vineyard system is profoundly complicated by the interactive effects of other biotic and abiotic stressors. From an ecological perspective, long-term FACE studies are the most realistic predictors of response to elevated CO2.

Advocating for long-term agroecological studies is necessary to evaluate the top-down and bottom-up impacts of higher carbon availability on pest/disease interactions, grapevine growth and phenology dynamics, and the resulting quality of wine produced. Grapevine physiology will be impacted by elevated carbon dioxide, increasing temperatures, and extreme heat events during the growing season . FACE experiments highlight the necessity of water availability for grapevines to take advantage of increased carbon dioxide for productivity. Soil water availability impacts the opening of stomata, and in the case of Vineyard FACE, the vines had increased gs with more CO2 available . Grapevines may need more water under future climate conditions of elevated CO2 and temperature, while precipitation is expected to decrease in most of the wine growing regions of the world. Desiccation threatens vines through water loss from latent cooling under elevated temperature, resulting in higher cumulative water loss even when operating at higher water use efficiency. The modulating response of stomata documented across literature is dependent on the soil water availability and temperature regimes . In this synthesis, the varying levels of CO2, ambient temperatures, and duration of these experiments could have contributed to these contrasting results of stomatal behavior, as well as the conditions of the chambers and greenhouses, versus FACE infrastructure. Physiological response to abiotic stresses in future climate change conditions is likely to weaken grapevine, creating a vulnerability for biotic stresses such as pests. Overall, chewing pest pressure is anticipated to increase as carbon dioxide and temperature increase . It is unknown whether pest pressure can be compensated by the predicted increase in foliar growth and the effect of lower nutrient density on the populations of pests.

The growing season for grapes may require drastic changes in viticultural practices to manage pests, alleviate heat and drought stress, and predict harvest dates. Fungal infections are responsible for a majority of crop damage; therefore, it is critical to clarify if fungal infection will decrease in the future for predictions of grapevine yield. One of the biggest challenges for grape growers will be the shifts in phenological timing, with the potential for frost at early bud break, alterations in cluster formation and density, and compromising harvest with early maturation. Many of the short-term experiments described here did not find significant effects on phenology and yield, while long term studies account for acclimation and compounding effects of seasonal exposure to elevated carbon dioxide. Predictions of overall vineyard response to climate change are more accurate when experiments are field based, multi-seasonal, and combine the variables of water availability and temperature. Climate change is increasing the growing season temperatures in many of the world’s most important winegrape growing regions. According to the most recent IPCC Assessment Report, Climate Change 2021, global warming is expected to exceed 1.5°C – 2°C during this century . Warming caused by anthropogenic greenhouse gas emissions advances phenology in hundreds of plant species, with increased consequences for perennial crops . Climate warming has already altered the phenology of many plant species globally, including the phenology of valuable crop plants such as grapevine . Winegrapes, a globally important crop both economically and culturally, have become an important indicator of climate change, with well documented advancing phenology, shorter periods between phenological stages , and large inter-annual variability . Adapting to climate change has become a global priority, and the wine industry is likewise looking for more accurate predictive measures of phenology and strategies for future planting. Culturally and economically, grapevine is one of the most valuable crops in the world, evidenced by an annual production of 60 million tons of fruit , with varieties that have been cultivated for thousands of years, selected for color, flavor, and phenological timing . Grape growth and qualities are sensitive to growing season climate fluctuations, and there is a direct link between warming temperatures and early harvest dates . Earlier ripening forces farmers to harvest grapes at optimal sugar levels during warmer periods of the summer. Harvest should ideally occur later during a cooler period of the growing season after the berry has accumulated an appropriate balance of acids of sugars. Early harvesting decreases the quality of wine, round plastic pot evidenced by early ripening significantly altering berry chemical composition . Higher year-round temperatures impact varieties with chilling requirements, such as California’s premiere wine grape, Chardonnay . Globally, there have been shifts of 1-2 weeks for winegrape growing regions . In Europe, the growing season has lengthened by about 11 days over the last 30 years, which will impact grape berry and wine quality . Early bud burst threatens frost damage during volatile Spring temperatures . At present, the winegrape crop in Bordeaux has a month earlier harvest than it did 50 years ago . Models of warming indicate that increases in temperature are not uniform globally and that warming has increased in the major wine growing areas of California and Western Europe more than South America and Australia during the past 50 years . The phenological shifts resulting from growing season temperature increases are documented internationally, and models predicting phenology using temperature are becoming more precise . A multitude of studies both observational and experimental have identified an acceleration of phenology and decrease in periods between stages in response to warming growing seasons , but some show trends of the intervals between each stage widening . Previous grapevine modeling which quantified relative sensitivity of many varieties combined records of phenology across variable microclimates and conditions . Comparing phenological timing from different vineyards done does not capture the influence of the microclimate and microhabitat; elevation, management, soil type, and a multitude of other environmental factors can impact flowering time . The ampelography vineyard at University of California Davis allows for attributing the variation in phenology to the specific sensitivity of cultivars to changes in climate, rather than soil type, irrigation method, pruning, or other major sources of variability found when comparing multiple vineyards.

Temperature is the main driver of phenological development for grapes; heat accumulation impacts the biochemistry important for cell growth . A study of 15 cultivars in Australia documented a plateau in growth between 22-29°C . For many plant species, higher temperatures can stagnate growth, and we expect that some varieties of grapevine would be sensitive to temperatures greater than 40°C . In extreme cases, beyond inducing premature veraison, heat stress will cause loss of berries, inactivate enzymes, and reduce development of flavors critical for wine quality . We integrate into our models a measure of extreme heat to determine its effect on veraison, the stage most likely impacted by these events. In this study, we examined variability in the phenological responses of 137 varieties of Vitis vinifera over a 5-year period. We examined variability in the timing, in terms of growing degree days, of the three major phenological stages: budburst, flowering, and veraison. Our data provide an updated reference to the last major study of variety-level phenological responses in California, which examined 114 varieties nearly 40 years ago . We also compare traditional Vitis vinifera species with hybrids grown at the University of California Davis, originally cultivated by Harold Olmo. Overall, this study offers a comprehensive look at international varieties planted in California their relative phenological response to climate. This study aims to evaluate a wide range of cultivars to identify regions with lower sensitivity to climate change that may be used in adaptation, either through breeding or planting as alternatives. The UC Davis ampelography learning vineyard has been developed over the past decade to include approximately 300 international varieties planted adjacent to the Viticulture and Enology academic building. The vines are planted in groupings by geographic origin, for the purpose of teaching. The vines are trellised using vertical shoot position , with regular irrigation, and are treated throughout the growing season with sulfur sprays for pests and disease. The current study of phenology has been tracking over 130 varieties for over four years and measures the response of the varieties through three main phenological stages: budburst, flowering, and veraison. The phenological data has been collected from UC Davis starting in 2014, continued through 2019. For each of 137 varieties, we recorded the timing of three major phenological stages: Budburst, Flowering, and Veraison. The same individuals were monitored for 5 years. For each vine, three positions on the cordon were chosen at the start of each season before budburst, following the previous year’s recorded positions unless damage had occurred, in which case a nearby cordon was chosen . The primary buds from each two-bud spur were chosen at the most basal position. The three buds were tracked through each phase, treated as technical replicates averaged for an overall estimate for each individual vine. Each vine is a biological replicate, and two vines per cultivar were measured. The timing of budburst was recorded as stages 1-13 , based on the modified Eichhorn–Lorenz stage of the three positions monitored for each vine . The EL scale describes the phenological stages of grapevine and categorizes the stages as follows: budbreak, shoot development, flowering, fruit set, berries pea-sized, veraison, and harvest . Flowering was monitored from these same shoot positions, and once clusters started to develop, they were marked with flagging tape.