Study on phenotypic variation of 5 wild Medicago falcata populations in Xinjiang

In this study, five populations of wild Medicago falcata from Xinjiang were examined. The genetic diversity of phenotypic traits in primitive populations was evaluated by analyzing the correlations, principal components, variability of distribution area, and variability of 20 phenotypic traits (including leaf, flower, and stem nodes) to provide valuable information for future research on genetic variation and germplasm innovation. Results showed that differences among populations were highly significant for all traits except leaf length and petiole length, though differences in these traits were still significant. Additionally, we found that M. falcata has rich polymorphism. The average coefficients of variation of phenotypic traits were 20.19% and 27.66% in the population and inter-population , respectively, which indicated that the main phenotypic differences of M. falcata came from the inter-population . Different degrees of correlation occurred among the 20 phenotypic traits. Negative correlations were observed between the number of branches and latitude and longitude, plant height, and altitude. Results also showed that the 20 phenotypic traits can be classified into 6 principal component factors with an accumulative contribution rate of 71.75%. The variation of phenotypic traits between populations was primarily due to leaf, internode, and flower features.