Abstract

Among all abiotic stresses, drought is undoubtedly the major factor, which, individually or combined with heat stress, limits crop productivity worldwide. Considering these facts, four spring barley and two spring wheat genotypes were evaluated under two stress (early and late) conditions in a southern arid region of Russia in order to identify suitable spring wheat and barley genotypes for that region and to assess the optimum sowing time for specific genotypes. High temperature followed by deficit soil moisture affected all stages from germination through to reproduction of crop when sown late, finally drastically reducing yield. On the other hand, due to low temperature, germination and stand establishment of crop sown early were highly affected, resulting in lower grain yield. Thus, high temperature (air and soil) followed by drought (deficit soil moisture) in the late-sown crop (from germination to reproductive stages) and low temperature in germination through vegetative stages of the early-sown crop are the most important constraints for crop production in this arid region. From the overall performance (yield, relative performance and stress susceptibility index), genotype ‘Zernograd.770’ is recommended for both early and late drought stressed areas and ‘Ratnik’ were sensitive to stress both at low temperatures when sown early and high temperatures followed by drought when sown late.

Key words: High temperature, drought, spring wheat, barley, Russia.