EFFECT OF WATER STRESS ON SOME PHYSIOLOGICAL TRAITS OF BREAD WHEAT GENOTYPES

Abstract

Water stress is the main environmental constraint to the wheat crop. The effects of water stress on some physiological parameters viz., relative water content (%), leaf area, chlorophyll content (%) and osmotic potential of newly evolved wheat genotypes were studied. Significant effects (P? 0.05) of water stress were observed on studied physiological parameters. Genotypes showed variable response to various water deficit conditions for their physiological traits. The reduction in osmotic potential under water stress is often considered as important adaptive physiological mechanism. The advance lines NIA-8/7, followed by BWM-3, NIA-9/5, NIA-37/6, NIA-10/8, NIA-28/4, NIA-30/5, NIA-25/5, ESW-9525, SI-91196, SI-9590, MSH-14, MSH-36, MSH-22, BWQ-4, BWS-78, BWM-47 showed significantly lower osmotic potential (ranged from -2.0 to -2.85MPa); while genotypes BWS-77, BWM-84, MSH-17 showed comparatively higher osmotic potential (less than -2.0MPa) under severe moisture stress. These results suggested that genotypes with the lowest osmotic potential possess more tolerance to drought as they have capabilities to maintain their osmotic potential under moisture stress. Genotype NIA-10/8 (86.1%), followed by 14 other genotypes had significantly higher relative water content (RWC) percent (above 69.5%) at severe water stress; which suggested that these genotypes could be more drought tolerant. Genotype BWS-78 showed significantly higher chlorophyll (51.67%) than other genotypes.

Keywords

• osmotic potential
• physiological parameters
• water-stress tolerance
• wheat