Its effects on cognitive development, fatigue and mortality have significant economic impacts, estimated at 7.9% of GDP in the case of Bangladesh . Vitamin A deficiency also is widespread and an estimated 190 million preschool children and 19 million pregnant women are affected. More than half of these are found in South and East Asia and under a third in Africa . Vitamin A deficiency is a major cause of blindness and weakened resistance to disease, resulting in the deaths of up to 3 million children each year . In Bangladesh, Cambodia, Nepal and the Philippines at least half of the preschool children and pregnant women are affected by micro-nutrient and vitamin deficiencies . Small variation in maternal diets, particularly reduction in micro-nutrient content, can have a significant impact on fetal growth and development. The interplay of the different micronu-trients and antioxidants found in vegetables has important health impacts, explaining for instance the higher birth weight of children in India, flood and drain table when mothers consumed higher rates of green leafy vegetables and fruits during pregnancy.
Diets rich in vegetables, in all their many forms to ensure an adequate intake of most micro-nutrients, dietary fibers, and phyto-chemicals can bring a much-needed measure of balance back to diets contributing to solve many of these nutrition problems . Good health depends on dietary diversity, and as poverty increases, human diets become less diverse. In impoverished countries the poor have little choice and are forced to rely on the cheapest available staples and dietary diversity and health suffer. In richer countries, changes in the food systems have made poor quality processed foods high in carbohydrates and fats more affordable, available, and accessible; this has most impact on the diets of the poor.The emphasis has been on ensuring supplies of macro-nutrients while putting less emphasis on major sources of micro-nutrients and vitamins, which means a focus on survival rather than on health. World vegetable production does not meet even the basic nutritional needs of most countries, and the resulting imbalanced diets are one of the world’s most serious health problems.
Continuing to focus on increasing the production of staples will only exacerbate the real food problem, which is one of imbalanced diets. A world vegetable survey showed that 402 vegetable crops are cultivated worldwide, representing 69 families and 230 genera . Vegetable crops, of which the leaves or young leafy shoots are consumed, were the most common group of vegetables utilized , followed by vegetable fruits . Below ground crop vegetable organs ranked as follows in frequency of use: roots > tubers > rhizomes > corms > stolons and together comprised 17% of the total number. Many vegetable crops have more than one part used. Most of the vegetables are marketed fresh with only a small proportion processed because as most vegetables are perishable by nature, consumption shortly after harvest is the best guarantee for optimal quality. Of these marketed vegetables, rolling bench only 67 have attracted great breeding attention by international seed companies, due to their large area of production and substantial consumption, 52 were considered minor, and other 87 were considered rare . In 2010 the global vegetable seed market was estimated at US$4.1 billion, of which 36% were for solanaceous, 21% for cucurbits, 13% for roots and bulbs, 12% for large seed, 11% for brassicas, and 7% for leafy and others vegetables . In the last 8 years global commercial vegetable seed sales had an annual growth rate of 5.8%.
There are now 7.2 billion human beings inhabiting this planet, and it has been projected that world population growth may exceed 70 million annually over the next 40 years. It is expected to reach approximately 9.5 billion by 2050, when approximately 90% of the global population will reside in Asia, Africa, and Latin American countries. With the increase in world population and consumption, and the advent of a high degree of growth and added value through biotechnology, the global market of vegetable seeds is expected to expand in future years. The worldwide consumption and importance of vegetables in the diet is difficult to estimate owing to scant production statistics. Even where crop reporting services are an integral part of the agricultural infrastructure, in-formation is available only for a small percentage of the vegetable crops grown. The consumption and caloric contribution of vegetables to the diet varies widely with geographical region, nationality, local customs, and cuisine. China is the largest consumer of vegetables in the world.