Genomic Regions Associated with Drought Tolerance and Other Traits in Lentils (Lens sp.)

Drought is one of the major constraints to lentil production worldwide, making the development of drought-tolerant varieties essential for stable yields. Identifying genes and markers linked to drought tolerance is a crucial first step. We analyzed 90 recombinant inbred lines (RILs) derived from an interspecific cross between the drought-susceptible Lens culinaris cv. Alpo and the tolerant L. odemensis ILWL235 to investigate genomic regions associated with drought tolerance. Using 4163 high-quality SNP markers obtained through Genotyping-by-Sequencing (GBS), we constructed a linkage map showing seven groups corresponding to the lentil chromosomes. The map spans 786.82 cM and covers 3.46 G bp, representing approximately 88% of the lentil genome. To assess drought tolerance, RILs were subjected to water stress under greenhouse conditions by maintaining the soil moisture at a 40% field capacity (FC) in pots for 15 days, with the leaf relative water content (RWC) recorded every two days. Plants were phenotyped for yield, 100-seed weight, and seed number under both control and stress conditions. We identified 26 Quantitative Trait Loci (QTLs) strongly associated with drought tolerance traits and found putative candidate genes for most of them. Additional traits, including stem pigmentation, flower coloration, seed coat patterning, and seed ground color, were also mapped, and their genomic locations validated the accuracy of our linkage map.