Effect of Drought Stress on the Physiology and Yield of the Pakistani Wheat Germplasms

Drought stress is the most important factor and ever-growing problem limiting wheat (Triticum aestivum L.) productivity worldwide. Wheat has physiological mechanisms that enable them to adapt drought stress and this adaptation may vary among different genotypes. This study was performed to investigate the physiological responses in twelve wheat genotypes under drought stress to identify drought tolerant genotypes. Stress was imposed by growing the genotypes under four irrigation treatments (T1-380 ml, T2-190 ml, T3-126 ml and T4-95 ml) with each fifteen days interval. The results revealed that electrolytes leakage was increased and other physiological characteristics such as turgidity, relative leaf water contents and plant yield were decreased during the increase in drought stress. The Tatara, ZAS-08, ZAS-42 and Ghaznavi-98 wheat genotypes exhibited the normal physiology and were considered as drought tolerant genotypes. The drought tolerant genotypes specified in this study will be grown in rain fed regions in order to improve the crop productivity and will be used in wheat breeding programs to produce a stress tolerant genotype.