Soybean genetic resources and crop improvement

The soybean (Glycine max (L.) Merr.) is an economically important leguminou s crop for feed, oil, and soyfood products. It contains about 40% protein a nd 20% oil in the seed and, in the international trade markets, is ranked n umber one in oil production (48%) among the major oil seed crops. Despite i ts economic importance, the genetic base of soybean cultivars is extremely narrow. The indigenous cultivars and landraces in East Asia are on the verg e of extinction, because farmers are now growing high yielding soybean cult ivars. The exotic germplasm, enriched with genes for abiotic and biotic str esses, has not been fully exploited by soybean breeders. Mutation breeding has improved the fatty acids of the soybeans and has produced soybeans tole rant to herbicides. By using recombinant DNA technology, Monsanto has produ ced stable glyphosate tolerant soybean lines known as 'Round Up Ready' soyb ean. DuPont is producing transgenic soybean lines with improved fatty acids content. The feasibility of developing hybrid soybeans is still an open qu estion.