Molecular signatures of elite brinjal varieties towards grouping and marker–trait association for shoot and fruit borer resistance

Aim: Molecular characterization of brinjal genotypes and exploring marker trait association with a number of antixenosis and antibiosis traits in relation to shoot and fruit borer (SFB) infestation. Methodology: Seven elite brinjal genotypes including the most sensitive and highly resistant checks against SFB were sorted out from a set of 101 germplasm stocks. These were subjected to infestation with SFB in Mylar cages. Data were recorded on antixenosis and antibiosis traits related to SFB infestation. Molecular profiling was done using five RAPD and four SSR primers and the binary marker data (presence and absence of band) were analysed for clustering pattern of genotypes and marker-trait association if any for SFB infestation in brinjal. Results: The RAPD primer OPN04 and two SSR primers smSSR03 and smSSR04 emerged as the highly informative, while OPD 16 (a RAPD primer) and smSSR01 and smSSR09 showed high Rp value. The clustering based on RAPD and SSR profiling was almost similar to the grouping based on antixenosis and antibiosis traits indicating good primer efficiency for screening against SFB infestation. A few RAPD markers revealed significant marker-trait association with a number of antixenosis and antibiosis traits, and more specifically with larval weight under SFB infestation. Besides, a 400bp molecular marker 'OPC05_8' had shown significant MTA with fruit infestation, trichome density and calyx length. Interpretation: The above trait–specific molecular markers may be considered useful for screening of parental lines against SFB tolerance, and as such may be used for marker assisted selection in brinjal breeding programs. Key words: Brinjal, Clustering pattern, Genotyping, Marker-trait association, Shoot and fruit borer infestation