Useful genetic diversity in germplasm collections of food and forage legumes from West Asia and North Africa

Abstract

The germplasm collections at ICARDA of faba bean, chickpea, lentil and forage legumes have been exploited by breeding programmes in the West Asia and North Africa region for production of improved cultivars. The first lines distributed were taken directly from the germplasm collections after initial evaluation. This formed the first flush of releases by national programmes, with 56 of 105 cultivars emanating from germplasm. A systematic evaluation of the food legumes for a wide range of morpho-agronomic characters based on the IBPGR/ICARDA descriptors has led to publication and widespread distribution of catalogues which, in turn, have led to an extensive use of the germplasm by national breeding programmes. In the period of 1990-1994, more than 5000 accessions of food legumes and more than 1900 accessions of forage legumes have been distributed per year. The most important use made of the germplasm collections has been their exploitation as a source for resistances and tolerances to biotic and abiotic stresses. These legumes often suffer severe yield loss due to disease and environmental stress; consequently, screening procedures were developed for the major biotic and abiotic stresses and were successfully applied in selecting sources of resistances and tolerances. The germplasm collections have also been used to improve the nutritional quality of these crops, both for human and animal consumption. Most of the food legume collections have been screened for protein content. The Lathyrus spp. collections have yielded lines with low levels of the neurotoxin ODAP (beta-N-Oxalyl-L-alpha,beta-Diaminopropionic Acid), which causes Lathyrism in humans and animals. These lines are being used extensively in the breeding programme. In addition to maintaining collections of the cultigens, ICARDA has also assembled large collections of wild relatives and progenitors of lentil and chickpea; and wild and weedy forms of the forage legume species. In the past five years the wild Lens and Cicer collections have been evaluated for resistances to biotic and abiotic stresses. These have been useful in providing sources of new, improved or multiple-stress resistance. They have also been useful in increasing yield potential and adaptation of the cultigens.