The BIA also established a GIS branch that encourages tribes and offers advice on tribal GIS development-although recent funding cutbacks have hampered this effort-and has stockpiled a considerable amount of tribal GIS data in their own library.68 Partly in response to these developments and partly because many Indian communities are deeply suspicious of the BIA-backed tribal governments where GIS managers are housed, a consortium of tribes in the northern Plains and another in the Rio Grande corridor have limited BIA and other federal agencies’ access to some of their databases, declaring some of their GIS proprietary in an attempt to protect sensitive and sacred geographical information. These and other longstanding problems associated with the allocation of political authority in Indian Country caused one geographer to raise questions about the path of GIs development, especially its transformative powers, surveillant capabilities, and political uses.69 Through experience working with GIS, many have come to see it as a contradictory technology that can both empower and marginalize people and communities. Arguments about the social impacts of GIS have grown in recent years, and a debate has surfaced in geography under the heading “GIS and Society.” One of the more interesting proposals emerging from that debate, and worth considering in Indian Country, is for development of “community-integrated GIS that focus on local empowerment through community, not government, 10 liter pot control of and access to digital geographic information. We think this review signals the arrival of geography as a small but important participant in American Indian studies.
Geographers are helping to illuminate the complexity and refinement of environmental modifications made by early Indians and perpetually revise our knowledge of these matters in virtually every region of the continent. They also are busy telling mainstream society that water is a vital cultural source-not just a scarce but necessary physical commodity-with the intent of altering the allocation and cost-benefit models used in managing it. Geographers continue to document land fraud through dispossession research in both historical and contemporary periods, sitting in courtrooms as expert witnesses to do so, and by trying to educate other geographers still steeped in traditions of seeing Indian land claims as an insignificant “interest” competing against “higher” uses. Geographers also continue to assert the centrality of land and place in Indian identity and to explore how attachments to place are manipulated by both individuals and the institutions that would control them. They continue to deconstruct the imprint of European and Euro-North American colonization and to unpack the sounds and silences in historical and contemporary maps and GIS, in part to promote more culturally sensitive applications of technology. Geographers are working with planners and tribal leaders to develop models for cooperative planning for future economic development. Increasingly, they are reflecting on their own positions as privileged researchers, teachers, and consultants. Finally, they are teaching all this to their students. By no means are we implying that everything is just fine in geography. For example, there is a sense among many AISG members that we can and should become more active and involved in issues of importance to Native people throughout North America, to the point of adopting advocacy stances more frequently.
Some of the work cited here leads in that direction, especially the accomplishments of those working on sources and development. However, much of the other work often seems to hold Indians at arm’s length. This may be because many geographers still look askance at colleagues who take on advocacy roles, believing that the mask of apolitical objectivity so often donned in the past is still worth wearing. Perhaps some are justified in their aloofness, preferring the detachment afforded by theoretical questions, or the solitude available in archives and libraries. On the other hand, theoretical and empirical work on material and ideal landscapes, identities, and represen- tations, and the research on historical and contemporary cartographies are among the fastest growing and most intellectually active areas of the field. It is also certain that there is much more that is needed in the field: historical studies exploring continuities in land use and governance for land claims; land use and place-name mapping and GIS for preservation of cultural sources; examinations of the spatial basis for self-governance and self determination to support sovereignty; critical approaches to the role of space and place in the social construction of “Indians” via public perceptions, legislative agendas, corporate intentions, and classroom teaching; continued work in deconstructing colonial legacies and postcolonial discourse in the effort to achieve genuine polyvocality; and analyses of the health care distribution system of the majority and its relationship to alternative medical systems available through local cultural practices. It is encouraging to see a diversity of topics and approaches being engaged with enthusiasm. And in all of it geographers increasingly realize that it is no longer possible to remain completely indifferent about the politics of their own research when studying North America’s Native communities, places where research, self-determination, and sovereignty now typically go hand in hand. Grapevine berry ripening can be divided into three major stages. In stage 1, berry size increases sigmoidally.
Stage 2 is known as a lag phase where there is no increase in berry size. Stage 3 is considered the ripening stage. Veraison is at the beginning of the ripening stage and is characterized by the initiation of color development, softening of the berry and rapid accumulation of the hexoses, glucose and fructose. Berry growth is sigmoidal in Stage 3 and the berries double in size. Many of the flavor compounds and volatile aromas are derived from the skin and synthesized at the end of this stage. Many grape flavor compounds are produced as glycosylated, cysteinylated and glutathionylated precursors and phenolics and many of the precursors of the flavor compounds are converted to various flavors by yeast during the fermentation process of wine. Nevertheless, there are distinct fruit flavors and aromas that are produced and can be tasted in the fruit, many of which are derived from terpenoids, fatty acids and amino acids. Terpenes are important compounds for distinguishing important cultivar fruit characteristics. There are 69 putatively functional, 20 partial and 63 partial pseudogenes in the terpene synthase family that have been identified in the Pinot Noir reference genome. Terpene synthases are multi-functional enzymes using multiple substrates and producing multiple products. More than half of the putatively functional terpene synthases in the Pinot Noir reference genome have been functionally annotated experimentally and distinct differences have been found in some of these enzymes amongst three grape varieties: Pinot Noir, Cabernet Sauvignon and Gewürztraminer. Other aromatic compounds also contribute significant cultivar characteristics. C13-norisoprenoids are flavor compounds derived from carotenoids by the action of the carotenoid cleavage dioxygenase enzymes. Cabernet Sauvignon, Sauvignon Blanc and Cabernet Franc are characterized by specific volatile thiols and methoxypyrazines. Enzymes involved in the production of these aromas have been recently characterized. Phenolic compounds play a central role in the physical mouthfeel properties of red wine; recent work relates quality with tannin levels. While the grape genotype has a tremendous impact on tannin content, the environment also plays a very large role in grape composition. The pathway for phenolic biosynthesis is well known, but the mechanisms of environmental influence are poorly understood. Ultimately, there is an interaction between molecular genetics and the environment. Flavor is influenced by climate, topography and viticultural practices. For example, water deficit alters gene expression of enzymes involved in aroma biosynthesis in grapes, which is genotype dependent, and may lead to increased levels of compounds, such as terpenes and hexyl acetate, 10 liter drainage collection pot that contribute to fruity volatile aromas. The grapevine berry can be subdivided into the skin, pulp and seeds. The skin includes the outer epidermis and inner hypodermis . A thick waxy cuticle covers the epidermis. The hypodermal cells contain chloroplasts, which lose their chlorophyll at veraison and become modified plastids; they are the sites of terpenoid biosynthesis and carotenoid catabolism. Anthocyanins and tannins accumulate in the vacuoles of hypodermal cells. Pulp cells are the main contributors to the sugar and organic acid content of the berries. Pulp cells also have a much higher set of transcripts involved in carbohydrate metabolism, but a lower set of transcripts involved in lipid, amino acid, vitamin, nitrogen and sulfur metabolism than in the skins. Concentrations of auxin, cytokinins and gibberellins tend to increase in early fruit development of the first stage. At veraison, these hormone concentrations have declined concomitant with a peak in abscisic acid concentration just before veraison.
Auxin prolongs the Stage 2 lag phase and inhibits anthocyanin biosynthesis and color development in Stage 3. Grapevine, a non-climacteric fruit, is not very sensitive to ethylene; however, ethylene appears to be necessary for normal fruit ripening. Ethylene concentration is highest at anthesis, but declines to low levels upon fruit set; ethylene concentrations rise slightly thereafter and peak just before veraison then decline to low levels by maturity. Ethylene also plays a role in the ripening of another non-climacteric fruit, strawberry. ABA also appears to be important in grape berry ripening during veraison when ABA concentrations increase resulting in increased expression of anthocyanin biosynthetic genes and anthocyanin accumulation in the skin. ABA induces ABF2, a transcription factor that affects berry ripening by stimulating berry softening and phenylpropanoid accumulation. In addition, ABA affects sugar accumulation in ripening berries by stimulating acid invertase activity and the induction of sugar transporters. It is not clear whether ABA directly affects flavor volatiles , but there could be indirect effects due to competition for common precursors in the carotenoid pathway. Many grape berry ripening studies have focused on targeted sampling over a broad range of berry development stages, but generally with an emphasis around veraison, when berry ripening is considered to begin. In this study, a narrower focus is taken on the late ripening stages where many berry flavors are known to develop in the skin. We show that that the abundance of transcripts involved in ethylene signaling is increased along with those associated with terpenoid and fatty acid metabolism, particularly in the skin.Cabernet Sauvignon clusters were harvested in 2008 from a commercial vineyard in Paso Robles, California at various times after veraison with a focus on targeting °Brix levels near maturity. Dates and metabolic details that establish the developmental state of the berries at each harvest are presented in Additional file 1. Berries advanced by harvest date with the typical developmental changes for Cabernet Sauvignon: decreases in titratable acidity and 2- isobutyl-3-methoxypyrazine concentrations and increases in sugar and color . Transcriptomic analysis focused on four harvest dates having average cluster °Brix levels of 22.6, 23.2, 25.0 and 36.7. Wines made in an earlier study from grapes harvested at comparable levels of sugars or total soluble solids to those in the present study showed clear sensory differences. Six biological replicates, comprising two clusters each, were separated into skins and pulp in preparation for RNA extraction and transcriptomic analysis using the NimbleGen Grape Whole-Genome Microarray.A note of caution must be added here. There are high similarities amongst members in certain Vitis gene families , making it very likely that cross-hybridization can occur with probes on the microarray with high similarity to other genes. We estimate approximately 13,000 genes have the potential for cross-hybridization, with at least one probe of a set of four unique probes for that gene on the microarray potentially cross-hybridizing with probes for another gene on the microarray. Genes with the potential for crosshybridization have been identified and are highlighted in light red in Additional file 2. The rationale to include them is that although individual genes can not be uniquely separated, the probe sets can identify a gene and its highly similar gene family members, thus, providing some useful information about the biological responses of the plant. An additional approach was taken, removing cross-hybridizing probes before quantitative data analysis . Many of the significant genes were unaffected by this processing, but 3600 genes were completely removed from the analysis. Thus, it was felt that valuable information was lost using such a stringent approach. The less stringent approach allowing for analysis of genes with potential crosshybridization was used here in the rest of the analyses. To assess the main processes affected by these treatments, the gene ontologies of significantly affected transcripts were analyzed for statistical significance using BinGO. Based on transcripts that had significant changes in abundance with °Brix level, 230 biological processes were significantly over represented in this group . The three top over represented processes were response to abiotic stress, biosynthetic process, and response to chemical stimulus, a rather generic set of categories.