Stress response behavior in different wheat species in relation to heat tolerance

Abstract

Eighty wheat genotypes, twenty each from Triticum aestivum, Triticum durum,
Triticum dicoccum and Synthetic T. aestivum were evaluated for terminal
heat tolerance by normal (non-stress) and late (stress) planting in field in
randomized block design with three replications for two crop seasons; 2012-13
and 2013-14. The genotypes differed significantly for grain yield in non-stress
and stress conditions. The heat susceptibility and tolerance indices were
calculated as Heat Sensitivity Index (HSI) and Heat Response Index (HRI)
for grain yield. Genotypes PBW 550, HD 2733, HD 2967, PBW 343 & PBW
373 from T. aestivum, WHD 943, WHD 945, WHD 314, WHD 946 & WHD
912 from T. durum, DI 26, DI 119, DI 88, DI 52 & DI 61 from T. dicoccum and
Syn 22, Syn 24, Syn 30, Syn 36, Syn 62 & Syn 25 from Synthetic T. aestivum
were found heat tolerant on the basis of heat susceptibility index and could
be useful as genetic stock to develop wheat heat tolerant varieties in breeding
programs. Synthetic T. aestivum was found to have lowest HRI followed by
T. durum, T. dicoccum and T. aestivum respectively while HSI was lowest in
T. durum, T. aestivum, T. dicoccum and Synthetic wheat lines respectively.