Association of DREB Genes and Microsatellite Markers Linked to NAX2 with Salt Tolerance in CIMMYT-derived Triticale, Wheat and Rye Genotypes

Abstract

Twenty-eight genotypes including triticale, wheat and rye were grown in a greenhouse under control, 14 and 21 dS/m salinity (NaCl and CaCl2, 1:1 ratio) levels to assess variations in agronomic traits, and to assess association of dehydration responsive elements (DREB genes) and five microsatellite (SSR) markers with salt tolerance. The results of grain yield variation and principal component (PC) analysis for statistical indices revealed that the first PC under 14 and 21 dS/m salinity levels was associated with salt tolerance. Five microsatellite (Xgwm291, Xgwm312, Xgwm410, Xgwm2181 and Xgwm126) and two DREB (DREB1 and DREB2) markers were used for detection of polymorphism. In total, 35 alleles ranging from 130 to 850 bp in size were identified of which, 25 alleles were found for SSR markers and 10 belonged to DREB genes. The number of alleles ranged from 3 to 9 with an average of 5 per primer. The polymorphic information content (PIC) value ranged from 0.51 (Xgwm291) to 0.77 (DREB1) with an average of 0.68. The Xgwm291 primer amplified 3 bands (130, 160 and 185 bp) in triticale and wheat but neither were detected in rye. Remarkably, the 130 bp band was amplified in TRT826 which was categorized as salt tolerant on the basis of K+/Na+ ratio and grain yield variations. Accordingly, this band could be associated with salt tolerance and its isolation and sequencing could clarify its characteristics for possible use in marker assisted breeding (MAB) for salt tolerance in triticale and wheat.