Resource use efficiency of different wheat species under drought stress

Genotypes of modern bread wheat (Triticum aestivum L.) produced significantly more grain yield over spelt (Triticum spelta L.) and emmer (Triticum dicoccum) genotypes of ancient wheat. Grain yield was more in bread wheat genotype than the spelt and emmer wheat species because of its higher harvest index. All three bread wheat genotypes had significantly higher harvest index over rest of genotypes while spelt had over both the genotypes of emmer wheat species. Grain/chaff ratio was the maximum in Einstein followed by Spelt, Xi19 and Claire. 1000-grain weight was higher in spelt followed by bread wheat and then emmer genotype. Einstein had maximum grain yield and harvest index among all genotypes. Water use efficiency was higher in emmer and spelt than bread wheat. The maximum water was transpired by Xi19 and least by Spelt SB in given period of time. Emmer and Emmer SB had maximum water-use efficiency followed by Spelt SB and then Einstein, Xi19 and Claire. The water-use efficiency ofEmmer, Emmer SB and Spelt SB were significantly higher over Claire. Emmer and spelt genotypes used irrigation water more efficiently than bread wheat genotypes. Linear regression between plant height and water used showed that emmer and emmer SB attained higher plant height consuming less quantity of water while it was reverse in bread wheat genotypes. The similar regression was observed for biomass production.The radiation-use efficiency of emmer and emmer SB were significantly higher over all three bread wheat, i.e. Einstein, Claire and Xi19 and Spelt SB.Traits highlighted to be useful, such as water and-radiation- use efficiencies, could be introgressed into modern bread wheat by making crosses with these related species.