Assessment of genetic diversity among alfalfa (Medicago sativa L.) genotypes by morphometry, seed storage proteins and RAPD analysis

Alfalfa is the world's widest grown forage crop with novel applications in the production of commercial proteins and biomass for biofuel. These alternative uses of alfalfa require new cultivars and breeding processes adjusted to specific production systems and demands. An estimate of the genetic diversity and differentiation between genotypes of breeding germplasm is of key importance for its improvement. Traditionally, it is has been achieved through morphological analyses, although novel methods of molecular marker analysis offer faster and more reliable tools. The objective of this study was to determine genetic variability of ten populations of alfalfa as a part of a collection at the Institute for Forage Crops, Kruševac, Serbia and to reveal relationships among genotypes through UPGMA1 cluster analysis. Data obtained through three different methods were compared and the correlation among them was estimated. It has been found that clustering of examined genotypes based on analysis of morphology traits has the best fit with geographical origin of genotypes. Methods using molecular markers, as seed storage proteins or RAPDs,2 provide a rapid way to discriminate between genotypes and have strong mutual correlation. Estimating the genetic distance through molecular marker analysis showed a poor fit of distance in relation to morphological analyses.

► Three methods were used to compare alfalfa cultivars.
► Morphological analysis grouped cultivars according to geographic origin.
► RAPD and protein markers gave highly correlated results.