Mapping QTL Associated with Traits Affecting Grain Yield in Chickpea (Cicer arietinum L.) under Terminal Drought Stress

Abstract

The aim of this study was to evaluate a set of recombinant inbred lines (RILs) for agronomic and physiological traits under drought conditions and to locate quantitative trait loci (QTL) associated with them. This study used a RIL population derived from a cross between drought tolerant (ILC 588) and susceptible (ILC 3279) genotypes. The population consisting of 155 RILs was grown under drought conditions in the field at Tel Hadya, Syria, in 2006 and 2007 and at Breda, Syria, in 2007. A genetic map consisting of eight linkage groups was developed using 97 simple sequence repeat (SSR) markers. The results revealed that high harvest index (HI), early flowering, and early maturity were the important attributes contributing to higher grain yield under drought. Higher stomatal conductance (gs) and cooler canopies (canopy temperature minus air temperature [Tc–Ta]) can also lead to better performance under drought conditions. Quantitative trait locus analysis identified 15 genomic regions significantly associated with various traits affecting drought tolerance in chickpea. Important QTL detected in this study included two QTL for HI explaining 38% of the total phenotypic variability of the trait, four QTL for flowering explaining 45%, and three QTL for maturity explaining 52% on a cumulative basis. Three QTL for gs and six QTL for Tc–Ta also detected explained 7 to 15% phenotypic variability individually. Two QTL (Q3‐1 and Q1‐1) on linkage group 3 (LG3) and LG1 showed effects on many traits related to drought. Hence, these regions can be further explored in future drought studies.

QTL detection for flowering time in faba bean and the responses to ambient temperature and photoperiod

“…Chr-I.B.3 is syntenic with M. truncatula chromosome 8 and chickpea chromosome 8 (Kaur et al 2014). Three flowering QTLs have been detected on M. truncatula chromosome 8 (Pierre et al 2008) and two on chickpea chromosome 8 (Rehman et al 2011;Varshney et al 2014). Sixteen flowering related genes have been identified on M. truncatula chromosome 8 by Kim et al (2013), including the photoperiod pathway genes: Casein kinase alpha 1 (CKA1); Casein kinase II, alpha chain 2 (CKA2); and Chryptochrome-interacting basic-helix-loop-helix 1 (CIB1).…”

Use of synteny to identify candidate genes underlying QTL controlling stomatal traits in faba bean (Vicia faba L.)

“…ILB 938/2 had lower g s , lower stomatal density, and hence lower productivity, and when exposed to drought conditions it had less reduction in g s and less change in canopy temperature than Mélodie/2. In chickpea, genotypes that maintained higher g s and kept cooler canopy temperature under drought stress conditions during the reproductive period performed better than those that did not (Rehman et al 2011). In faba bean, it was shown that accessions with higher stomatal density had less resistance to water stress (Ricciardi 1989).…”

Genomics-assisted breeding for drought tolerance in chickpea

“…In terms of abiotic stresses, Vadez and colleagues (2012) at ICRISAT identified QTLs for salinity tolerance and inferred that tolerance is associated with earliness in chickpea. Although efforts were made to understand drought tolerance (Rehman et al 2011;Hamwieh et al 2013), the studies aimed to understand the performance of agronomic or physiological traits. Recent research endeavours at ICRISAT by Varshney et al (2014b) may eventually lead to a comprehensive understanding of drought tolerance in chickpea.…”