Identification Of Quantitative Trait Loci (QTL) For Salt Tolerance In Soybean.

Soil salinity is a severe abiotic stress that adversely affects the soybean production. Salt stress inhibits soybean germination, plant growth, and seed yield. Development of salt-tolerant cultivars is an effective method of combating salt-related yield loss. Marker assisted selection will facilitate the breeding for salt-tolerant lines, provided that stable QTL regions and linked markers are identified across the environments. The objectives of this study are to identify new QTLs/markers associated with salt tolerance, and to confirm the previous reported QTL for salt tolerance. Two hundred F_2:3 lines derived from the cross V05-2326 (salt-sensitive) x Osage (salt-tolerant), 124 F_4:6 lines derived from the cross RA-452 (salt-sensitive) x Osage (salt-tolerant), along with these three parental genotypes were evaluated for salt response in greenhouse. Chi-square test of leaf scorch scoring indicated that the salt tolerance is controlled by a single gene. Tissue analysis of leaf chloride content will be used to confirm the segregation ratio. All the lines will be genotyped with 5361 SNP markers using the Illumina Infinium® Genotyping HD BeadChip (652k SNPs). A major salt-tolerance QTL is hypothesized to be identified using SNP marker analysis in this study.