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

Abstract

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.