Effect of Terminal Drought Stress on Morpho-physiological Traits of Wheat Genotypes

Drought Stress Effect on Wheat

Abstract

Development of wheat varieties with low moisture requirements and their ability to withstand
moisture stress may cope-up well with the on-coming peril of drought conditions. Ten wheat genotypes
including two new strains, PBGST-3, Hero, Bhittai, Marvi, Inqlab, Sarsabz, Abadgar, Kiran, Khirman and
PBGST-4 were sown in split plot design with factorial arrangement in four replications at Experimental
Field, Department of Plant Breeding & Genetics, Sindh Agricutlure University, Pakistan during 2012-13.
The results revealed that water stress caused significant reductions in all morpho-physiological traits. The
genotypes differed significantly for all the yield and physiological traits. The interaction of treatments ×
genotypes were also significant for all the traits except plant height, productive tillers/plant, grains/spike
and harvest index, were non-significant which indicated that cultivars responded variably over the stress
treatments suggesting that breeders can select the promising genotypes for both stress and non-stress
environments. Among the genotypes evaluated Bhittai, Kiran-95, PBGST-3 and Sarsabz showed good
performance as minimum reductions occurred under terminal stress conditions for all the traits studied.
Hence, above mentioned genotypes were considered as drought tolerant group. The high positive correlations
of physiological traits like chlorophyll content and relative water content with almost all yield traits indicated
that these physiological traits could serve as reliable criteria for breeding drought tolerance in wheat. The
negative correlations of electrolyte leakage with several important yield traits indicated that though this
physiological trait has adverse effect on yield attributes, yet it could reliably be used to distinguish between
drought tolerant and susceptible wheat genotypes.