Assessment of genetic diversity at molecular and morphological levels of temperate maize landraces collected from diverse ecological niches in Kashmir

A study was conducted to carry out morpho-molecular characterization of 70 maize landraces collected from diverse ecological niches. The ANOVA revealed significant differences for all the traits studied except prolificacy and anthesis silking interval. Phenotypic performance-based clustering using Mahalanobis distance resolved these landraces into four major clusters. The PIC values for the 25 SSR markers ranged from 0.29 (phi 129) to 0.82 (bnlg 1335) with a mean value 0.51. Analysis of molecular variance revealed that the total genetic diversity is mainly due to within population diversity (93%). Average heterozygosity from all SSR loci was 0.15 and gene diversity ranged from 0.87 (bnlg 1335) to 0.32 (phi 021) with a mean value of 0.56 indicated a high level of polymorphism among landraces. The population structure analysis revealed the existence of two groups reflecting major divisions of the germplasm collected regardless of their geographical origin. Clustering method based on Jaccard similarity coefficient and an UPGMA further confirmed the two major clades with a significant level of similarity (0.28 to 0.76) among the landraces. Sub population! was found to be genetically more diverse with an Fst value of 0.18 than sub population 2 with Fst value of 0.10. The results showed that the studied maize landraces are diverse making them ideal source population.