Genetic architecture and population structure of Oat Landraces (Avena sativa L.) using molecular and morphological descriptors

Oat is grown as winter forage in India. It is a self-pollinated crop with less variability. However, the variation for different morphological traits in oat germplasm may be available at genotypic level. The present study was conducted to find out the genetic diversity among 24 oat landraces using 9 morphological traits and 24 SSR primers. Morphological data observed across the 24 landraces showed wide variation and grouped various landraces into two clusters. GFY and DMY were positively and significantly correlated with most of the traits studied. The molecular analysis using 24 SSR primers resulted amplification of 62 polymorphic alleles with an average of 2.58 alleles per primer. Size of amplified alleles ranged from 70 to 480 bp. Mean polymorphic information content was 0.42 showing moderate level of SSR polymorphism. Cluster analysis based on SSR data differentiated 24 oat landraces into three major clusters. Bayesian model-based STRUCTURE analysis assigned landraces into two clusters and showed the extent of admixture within individuals. Clustering pattern of oat landraces based on SSR marker profiles were different from that of morphometric traits. So, based on the pooled analysis at morphological and molecular level, the landraces IG-02-121, IG-02-129 and IG-02-113 were found superior for morphological traits as well as most distant among all the landraces under study. Hence, these landraces could be used in for future breeding programmes for genetic improvement in oats.