Effect of drought on grain yield in 23 wheat (Triticum aestivum L.) lines in Karaj conditions

In order to evaluation of grain yield changes and some physiological triats in bread wheat genotypes under drought stress during garin filling period, this study was conducted with 23 bread wheat lines and cultivars including twenty drought resistant and three susceptible lines in split plot design with three replications. Main and sub plots were allocated to irrigation and wheat cultivars/lines, respectively. Irrigation treatments were including full irrigation and drought stress during flowering stage. The results showed that the effects of irrigation regimes on thousand kernel weight and number of spike per square meter were statistically significant at 1% and 5% levels respectively. The seed weight and the number of spike per square meter was more important in grain yield in both irrigation regimes. The maximum thousand grain weight by 38.7 g recorded in SD-86-14 and SD-86-3 most spike m2 obtaind by 1087 in Chamran variety and the best result for grain yield considered in SD-86-11 by 7170 kg/ha.