Molecular mapping of drought and heat tolerance traits using interspecific cross in chickpea (Cicer arietinum L.)
Loading...
Date
2018
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Punjab Agricultural University, Ludhiana
Abstract
To understand the complex mechanisms of drought and heat stress tolerance, molecular mapping of RIL population through ddRAD-Seq has been undertaken. In this study, all the traits measured were significantly affected by drought stress environment except harvest index as well as by heat stress environment except hundred seed weight and harvest index. The pooled ANOVA for all the traits measured showed highly significant differences in irrigated, rainfed and latesown conditions for genotypic variance as well as for standard error variance. Correlation coefficient exhibited strong association of traits with yield under drought and heat stress conditions. Multiple linear regression analysis revealed the contribution of traits towards the total variation in yield under drought and heat stress conditions. Path analysis explained that biomass followed by harvest index were the major contributor to grain yield under non-stress as well as drought stress and heat stress environment at both locations (Ludhiana and Faridkot) with pooled condition. Principal component analysis also revealed the strong positive association among the traits. In genotypic analysis, a total of 1365 filtered polymorphic and functional SNPs loci were used for linkage map construction through ddRAD-Seq. The average linkage map distance was 4569.09 cM with an average interval of 6.79 cM between the markers. Five QTLs of days to germination (qdg-1), days to flowering initiation (qdfi-1), days to 50% flowering (qdff-1), days to 100% flowering (qdhf-1) and yield (qyld-1) identified using BLUPs under heat stress condition. A total of twenty eight QTLs for days to flowering initiation (qdfi-1 to qdfi-4), days to 50% flowering (qdff-1 to qdff-4), biomass (qbio-1 to qbio-4), yield (qyld-1 to qyld-3), days to 100% flowering (qdhf-1 to qdhf-2), harvest index (qhi-1 to qhi-2), relative leaf water content (qrlwc-1 to qrlwc-2), root-shoot ratio (qrsr-1 to qrsr-2), root dry weight (qrdw-1 to qrdw-2), hundred seed weight (qhsw-1), membrane permeability index (qmpi-1) and fresh root weight (qfrw-1) identified using BLUPs under drought stress condition. These SNPs loci need to be validated in different genetic background and use them in marker-assisted selection for developing superior varieties with enhanced drought and heat tolerance.
Description
Keywords
null