Detection of QTLs associated with salinity tolerance in durum wheat based on association analysis

Abstract

Salinity is globally a major constraint for crop production. Breeding for salinity tolerance is an effective approach to improve crop production and productivity under saline conditions provided it is based on a good understanding of the genetic control of salinity tolerance. This study deals with mapping QTLs for salinity tolerance in durum wheat (Triticum durum) by association analysis using SSR markers. A total of 119 varieties were treated in 100 mM of NaCl solution and the salinity tolerance indices (STI) for several traits were calculated as parameters to assess salinity tolerance. Among the traits assessed, the increased proportion of dead leaves (%DL) was the most suitable parameter for assessment of salinity tolerance in durum varieties at early vegetative stages because of a broader range of variation among varieties and narrower range of variation within varieties compared to other traits. The QTL associated with salinity tolerance using %DL as a parameter was detected on chromosome 4B. An additional 11 QTLs associated with seven parameters using STI of other traits were detected on chromosomes 3A, 5A, 5B, 6A and 7A.