Effect of Spring cold stress pattern on the membrane stability and plant pigments in twenty bread wheat cultivar

Spring cold stress is a problem for wheat crops at heading and also may be damaged some other parts of this plant. The aim of this study was the investigation of spring cold stress on the physiological traits, plant pigments (total, a and b chlorophyll and Carotenoid) and cell membrane damage at the reproductive stage with the artificial conditions. For this purpose an experiment with 20 varieties of wheat with four treated cold level of stress (8 (control), +2, 0, 2 Celsius) in factorial arrangement in a randomized completely design implemented. Results of variance analysis showed the effects of interaction between cultivars spring cold levels is signification at the 5% level. Comparison between the interaction of all of traits showed the tolerant cultivars have more little cell membrane leakage and more plant pigments at the different levels of artificial Spring cold stress and PISHTAZ and AZAR 2, are the most tolerant cultivars andBECK CROSS.ROSHAN is the most susceptible cultivar. The results showed different reactions between cultivars and therefore these cultivars have considerably genetic diversity.