Ramesh S Bhat
University of Agricultural Sciences, India
Title: Validation of late leaf spot and rust resistance linked markers using near isogenic lines derived from heterogeneous inbred families in peanut (Arachis hypogaea L)
Biography
Biography: Ramesh S Bhat
Abstract
Peanut (Arachis hypogaea L) is an important oilseed crop severely affected by foliar diseases like late leaf spot (LLS) and rust. Molecular markers linked to LLS and rust resistance will be of immense use in complimenting conventional breeding for diseases resistance in peanut. Validation of markers linked to LLS and rust resistance is a pre-requisite for their use in Marker Assisted Breeding to develop resistant cultivars. Near isogenic lines (NILs) are the most preferred genetic stocks to validate the markers. The present investigation was aimed to develop NILs from heterogeneous inbred families (HIFs) to validate markers linked to LLS and rust resistance. NILs were developed from HIFs of TAG 24×GPBD 4 and TG 26×GPBD 4. The sets of plants belonging to the same HIF but differing significantly in LLS and/or rust resistance but not for other morphological and productivity traits were regarded as NILs. A total of 30 rust resistant, 34 rust susceptible, 21 LLS resistant and 25 LLS susceptible lines were isolated from TAG 24×GPBD 4 and TG 26×GPBD 4. Largely, rust/LLS resistant NILs had GPBD 4-type allele and susceptible NILs carried either TAG 24 or TG 26-type allele at the three SSR loci (IPAHM103, GM1536 and GM2301) linked to a common genomic region governing LLS and rust resistance. Comparison of the remaining genomic regions between the NILs originating from each of the HIFs using a large number of background markers indicated a considerably high genome similarity. These NILs are useful in fine mapping to identify candidate genes governing LLS and/or rust resistance.