Salinity tolerance in Bread wheat: Germplasm status, Molecular diversity and in vitro screening for K:Na discrimination levels

Abstract

Salinity stress is an important abiotic yield limning facto r. Present study covers the characterization of important germplasm comprised of synthet ic hexaploids and some historical genotypes important for salinity tolerance studies. The resu lts revealed that synthetic hexaploids nre genetically more diverse than tester set germplasrn in terms of phonological attributes. In vitro screening \\'85 a lso performed at 75mM NaCl salt stress. The genotypes found to be promising under salt stress conditions include SH-13, SH-12 and SH7 among syn thetic hexaploids and Kharchia, LU-26S, Calafia, Chinese Spring and Pasban-90. Molecular diversity based on SSR and RAPD markers among these synthetic hexaploids and tester set genotypes also revealed significant results. Results based on SSR better discriminated genotypes as compared to SSRs. Moreover SSRs used in this study were specific to A-genome hence determining the diversity specific to A-genome in the germplasm studied. Higher level of polymorphisms in synthetic hexaploids as ~o mpared to tester set genotypes based on A-genome S~Rs yielded the information that apart from D-genome di versity these synthet ic hexaploids also possess desirable divers ity in A-genome as well.