Abstract

Genetic Mapping of the Serrated Leaf Trait in Indian Mustard (Brassica juncea)

Priyansha Singh, PhD scholar, University of Delhi, South Campus

Leaves exhibit amazing variations in shape and size, both of which result from a complex network of hormone signalling and wide array of genetic factors. The lobed leaf character is an easily recognisable and unique morphologic trait in Brassicas, with potential advantages for agricultural productivity. Brassica juncea var. tumida is quite distinct in leaf morphology with its serrated margins. For genetic mapping of the serrated leaf character, tumida was crossed with popular and high yielding B. juncea var. Varuna, which has smooth margins. The F1 plants showed an intermediate leaf type. A large number of doubled haploids were raised, and were phenotyped for their leaf morphology and 11 main agronomic traits. The doubled haploid lines were genotyped with intron polymorphisms, microsatellite, KASPar and genotyping by sequencing (GBS) based SNP markers. Twenty-one restriction enzyme combinations were tested using IgCoverage for in silico evaluation of genomic coverage through GBS. A genetic map was developed and primary genetic analysis of the serrated leaf character was performed which mapped it to a 417.5 kb region of B. juncea A10. Fine mapping in this region is underway for the identification of candidate genes which will facilitate the cloning and identification of the target gene.