GERMINATION SALT RESISTANCE OF ALFALFA (MEDICAGO-SATIVA L) GERMPLASM IN RELATION TO SUBSPECIES AND CENTERS OF DIVERSITY

Saline soils and water severely limit the productivity of crop and pasture lands in semiarid and arid environments. The breeding of salt resistant cultivars of some crops is a partial solution to this problem. To breed for increased salt resistance, scientists must characterize the potentials and limitations of germplasm resources. This study measured the salt resistance of 761 alfalfa (Medicago sativa L. Emend. Sensu Lato) plant introduction accessions to NaCl during germination and characterized the resistance by subspecies, country of origin, and center of diversity. Experiments indicated that germplasm from the arid Indian and African centers excelled in NaCl resistance during germination. Germplasm from the Falcata center was least resistant. M. sativa L. subsp. sativa was more than twice as resistant as M. sativa L. subsp. ambigua or subsp. falcata. Thus, more resistant germplasm potentially adapted to the warm desert regions is available than resistant germplasm better suited to alfalfa production in more temperate regions. © 1990 Kluwer Academic Publishers.