IMPACT OF SOIL WATER DEFICIT ON SOME PHYSIOLOGICAL PARAMETERS OF DURUM AND BREAD WHEAT GENOTYPES

Abstract

SUMMARY Drought is a worldwide issue that impacts seriously on the security of food production. The aim of this research was to study the effect of soil water deficit on some physiological parameters of durum and bread wheat genotypes. Gas exchange parameters of flag leaf measured by using LI-COR 6400-XT Portable Photosynthesis System. Drought caused of reduction photosynthesis rate (Pn), stomatal conductance (gs), transpiration rate (E), mesophyll conductance (gm), photosynthetic pigments content, leaf area (LA), dry weight (DW), relative water content (RWC) of flag leaf. Leaf specific mass (LSM) was increased under rain-fed condition. Strong relationships were detected between gs and E, between gm and Pn. The Pn was positively and significantly correlated with LA, RWC, and DW but non-significantly correlated with Chl content. Physiological traits can be used as selection criteria for drought resistance.