ABSTRACT
Legumes, together with cereals, have been fundamental to the development of modern agriculture. Since the dawn of civilization, many legume species have been instrumental in supplying human food (e.g., soybean, Glycine max (L.) Merr.; common bean, Phaseolus vulgaris L.; pea, Pisum sativum L.; peanut, Arachis hypogaea L.; lentil, Lens culinaris Medik; and chickpea, Cicer arietinum L.), edible oils (peanut, soybean), and animal fodder and forage (alfalfa, Medicago sativa L.; and clovers, Trifolium spp.) (1). Legumes are second only to grasses in importance for human and animal dietary needs. Worldwide, grain and forage legumes are grown on 12-15% of the arable land (about 180 million ha) (2). They provide 33% of the nutritional nitrogen requirements of humans (3). In 2002, U.S. soybean production was 79 million metric tons and alfalfa production was 74 million metric tons (4, 5). The direct value of U.S. production of soybean and alfalfa in 2002 was $20 billion.
