Intra- Cultivar Variability Endorsed By Ssr Markers In Mango

Abstract

Appreciable intra cultivar variation has warranted clonal selections, which has emerged as an important tool in mango breeding. This important source of morphological variability manifested in altered fruit and quality attributes has yielded improved clones in India and abroad, few of which were exposed to SSR based analysis. Statistical parameters viz., Polymorphic Information Content (0.319 in MiIIHR12 to 0.819 for MiIIHR26) and Gene Diversity (0.399 in MiIIHR12 to 0.839 for MiIIHR26), defined the ability of the chosen SSR markers to discriminate the intra cultivar variability, besides highlighting the extent of diversity captured by the improved clones. Furthermore, genetic relationship among the clones derived by Wards minimum variance, placed Himsagar and Langra clones in Cluster I and II respectively, Himsagar recording high genetic heterogeneity within its cluster, intra cultivar variability being 0.16-0.916, thus showing suitability for breeding by clonal selections. Even the use of limited SSR marker loci (6), could reveal and document the genomic variations accounting for the variations in the Dashehari clones as well as placing land race ‘Suraiyya’, as an out-group. The sampled clones of elite variety Chausa did not show any variation at the studied marker loci, thus exposing limited heterogeneity in the clones and demanding more explorations for breeding superior types targeting regularity in bearing.