QTL mapping for morphological and physiological traits in RILs of spring wheat population of WH1021 × WH711

ABSTRACT

Aim: To identify the quantitative trait loci (QTLs) associated with various morphological and physiological traits. Methodology: A recombinant inbred line (RIL) population of wheat (Triticum aestivum L.) derived from cross of heat tolerant parent WH1021 with heat sensitive parent WH711 was used. For creation of heat stress delay in sowing (four weeks) was done in late sown from timely sown. Days to heading, days to maturity, plant height along with physiological traits viz. photosynthetic rate, transpiration rate, intrinsic water use efficiency (iWUE) and normalized difference vegetative index (NDVI) were recorded in both timely and late sown conditions over two years. Results: A linkage map consisting of 22 SSR was prepared covering eleven chromosome of wheat. Using the software WinQTL cartographer version 2.5, significant genomic regions associated with heat tolerance were observed on 2A, 2D, 4A and 5A chromosomes with composite interval mapping. QTLs for photosynthetic rate were found consistently for both years on chromosome 2D. In present study, significant variation was reported for days to heading and its QTLs were identified on chromosome 2A and 2D. Interpretation: The QTLs obtained for physiological and morphological traits in wheat can be used for marker-assisted selection for heat tolerance in wheat