REGIONAL DIVERSITY IN NONDORMANT ALFALFAS FROM INDIA AND THE MIDDLE-EAST

Alfalfa (Medicago sativa L.) is an important crop in many desert regio ns with long growing seasons. Very non-winterdormant (nondormant) cult ivars are derived primarily from germplasm obtained from low elevation s in the Middle East and India. Improved understanding of diversity in alfalfas from these regions may enhance conservation and utilization of this germplasm resource. To better characterize patterns of diversi ty in very nondormant Indian and Middle Eastern alfalfas, we evaluated 34 accessions from low elevations in western, central, and northern I ndia, and throughout the Middle East in a field trial in Tucson, AZ, d uring 1989 to 1992. Middle Eastern accessions included representatives of geographical groups formulated in previous research. Cluster analy sis and plots of the first three principal components of 12 agronomic and six morphological traits were used to describe patterns of variati on among accessions. Both analytical approaches showed that Indian acc essions were phenotypically distinct from the Middle Eastern germplasm evaluated. Northern Indian germplasm was much more persistent and hig her yielding than that from western India and was generally more simil ar to the majority of Middle Eastern accessions than to accessions fro m western India. Most accessions from the Gujarat state in western Ind ia were exceptional, exhibiting very poor persistence and adaptation t o temperatures near 0-degrees-C. Arabian accessions were generally dis tinctive, especially those from western and southern Arabia which exhi bited very rapid regrowth following harvest. Results of this study and previous research suggest that at least six regional germplasm groups exist among nondormant North African, Arabian, and Indian alfalfa ger mplasm.