Screening salt tolerance germplasms and tagging the tolerance gene(s) using microsatellite (SSR) markers in wheat

Salt-affected soil is a serious global problem. Most of wheat (Triticum aestivum L.) are sensitive to high levels of salt in soil; However, a number of wild relatives of wheat are tolerant to high levels of salt. Several lines, including the hybrids between wheat and Secale cereale L. and the hybrids between wheat and Leymus chinensis (Trin.) Tzvel., were investigated under salt stress. Four hundred accessions of collections were screened by salt stress during germinating and seedling stages. Eleven lines showed high tolerance to salt stress, they are Triticum aestivum L. cv. Hongmazha (landrace), Keyi 26, Hope; wheat-rye hybrid, 98-46, 98-113, 98-131; wheat-Leymus hybrid, 98-160, 98-161, 98-163. The lines with remarkable tolerance to salt stress are 98-160, 98-113. Genomic in situ hybridization and acid polyacrylamide gel electrophoresis (A-PAGE) analysis of gliadin and SDS-PAGE analysis of low molecular weight glutenins proved that 98-131 was a stable 1BL/1RS translocation and 98-113 was an addition line with one pair of unidentified rye chromosomes. Further salt stress response test of 1B/1R substitution/translocation lines indicated that IRS might have salt tolerance gene(s). SSR markers were employed to target the salt tolerance genes of 98-160 in its F-2 population with salt sensitive line, Banacaka Mska. The analysis displayed that SSR markers WMS67 and WMS213 mapped on 5BL were linking to salt tolerance gene(s). Genetic distance of die two markers to the critical gene ( s) are 13.9 cM (centMorgan), 31.0 cM, respectively. It is suggested that in 98-160 line, are salt tolerance might be controlled by major gene (s) on 5BL.