Ecology, Environment and Conservation Paper

VALIDATION OF SSR MARKERS LINKED TO LATE LEAF SPOT AND RUST IN GROUNDNUT (ARACHIS HYPOGAEA L.)

Shivaleela Kukanur, D. L. Savithramma, Sheela Duddagi, A. Vijayabharathi, B.P. Mallikarjuna1 and H.D. Pushpa

Abstract

The low productivity of Groundnut in India is ascribed to many biotic and abiotic stresses in the cultivation of the crop. Among the biotic stresses, the two major foliar diseases viz., late leaf spot (Phaeoisariopsispersonata [(Berk. and Curt.) Deighton] and rust (Puccinia arachidis Speg.) causing yield loss up to 50-70 per cent (Subrahmaniyam et al., 1984). The experiment was conducted at UAS, Bengaluru during 2011 and 2012 to validate the markers IPAHM 103, GM 2301 and GM 1009 identified to be linked to rust resistance and late leaf spot resistance respectively in different genetic backgrounds i.e., validating these markers over a set of resistant and susceptible genotypes for their utilization in marker assisted selection (MAS). During kharif 2011 minicore along with other advanced breeding lines were phenotypically screened for late leaf spot and rust disease using modified 9 point scale (Subbarao et al., 1990). Few genotypes consisting of minicore accessions, advanced lines and local cultivars were selected for validation of the above mentioned markers. The DNA extraction was done as per CTAB method given by Saghai-Maroofet al. (1984). Polymerase Chain Reaction (PCR) was performed by using a Touch-Down PCR. Through single marker analysis it was found that these markers IPAHM 103, GM 2301 and GM 1009 were found to be associated with rust resistance and late leaf spot resistance respectively in this study. Hence these markers can be effectively used for MAS for selecting the resistant genotypes inearly generations of resistant breeding.