Simple sequence repeat (SSR) polymorphism in the tropical Asian maize inbred lines differing in resistance to banded leaf and sheath blight (Rhizoctonia so/ani f. sp. sasakil)

Abstract

A set of 23 tropical maize inbred lines, including 18 from the CIMMYT-Asian Regional Maize Program (CIMMYT-ARMP) and 5 inbred lines developed under the All-India Coordinated Maize Improvement Project (AICMIP), were selected for this study. These lines, with distinct differences in responses to Banded leaf and Sheath Blight (BlSB; Rhizoctonia solani f. sp. sasakil) at different locations in India (Delhi, Pantnagar and Udaipur), were analyzed using 49 polymorphic simple sequence repeat (SSR) markers (179 SSR alleles). The study aided in genotype differentiation as well as analysis of genetic diversity among the lines. Besides revealing high genetic diversity among the tropical/sub-tropical Inbred lines, cluster analysis using SSR dataset clearly demonstrated the genetic distinctness of the CIMMYT-ARMP lines vis-a-vis maize inbreds developed in India. The study also aided in identifying suitable lines with phenotypic contrast (BlSB resistance) and genetic divergence. The information would be helpful in undertaking detailed genetic and molecular analyses of BlSB resistance, besides planned utilization of promising genotypes in breeding for BlSB resistance in the tropical maize germplasm.