Screening for drought tolerance in safflower genotypes- using physiological indices

Drought is one of the major limitations to plant productivity worldwide. Identifying suitable screening tools and quantifiable traits would facilitate the crop improvement process for drought tolerance. In the present study, relative water content, leaf area index, density and length stomata were physiological parameters which we evaluated fifteen spring safflower genotypes (factor A) in grain-filling stage under drought stress and non stress conditions (factor B) in the 2007 growing season in the Zanjan university. The experimental design was a strip – plot based on randomized compelet block with three replications. Exposure of plants to drought led to noticeable decreases in relative water content, leaf area index and the length of the stomatal with increase in density stomatal. The results of principal component analysis showed First component accounted for 68% of total variation. The first principal component indicated that relative water content, leaf area index, the length of the stomatal and grain yield were important characters for classification. The results have been shown that PI-537598 Dincer، Kino-74، PI-250537 and Gila genotypes can planted in water deficit regions.