PHYSIOLOGICAL EVALUATION OF SOME WHEAT GENOTYPES UNDER WATER DEFICIT CONDITIONS

Water deficiency in plant impairs the numerous physiological and metabolic functions. Selection of wheat genotypes that can tolerate water deficiency would be helpful tools for breeding program aiming to develop drought tolerant variety under water limited regions. Four wheat genotypes i.e (Misr 1, shandweel1, line 1 and line 2) were grown under four water regimes i.e 2400m3/fad (Wet), 2100m3/fad (Moist), 1800m3/fad (Medium) and 1500m3/fad (Dry) in wiry greenhouse at Giza Agricultural Research Station, (30.0204508, 31.2067921) ARC, during the two winter growing seasons of 2018/2019 and 2019/2020 to evaluate two promising line compared to two commercial wheat cultivar under water deficit. Important physiological traits of specific leaf area (SLA), crop growth rate (CGR), relative water content (RWC), stomatal resistance (SR), transpiration rate (TR), Photosynthetic pigments, Proline, total phenolic and glycine betaine, and lipid peroxidation (MDA) were studied. Results showed highly significant difference among wheat genotypes in all studied traits. The superior line1 indicated higher growth parameters, SLA, CGR, RWC, SR, Photosynthetic pigments, Proline, total phenolic and glycine betaine and showed decline in MDA and TR under1500m3/fad (Dry). These traits are recognized as beneficial drought tolerance indicators for selecting tolerant genotypes. Similarly, grain yield t/ha, straw yield t/ha, total soluble protein in grain, water productivity and harvest index of the same wheat genotype were also higher. I could be used as a good source for drought tolerant criteria in wheat breeding program.