در مرحله رشد رويشي )GLYCIN MAX.L( بررسي تحمل به خشكي 11 ژنوتيپ سويا

Evaluation of drought tolerance of soybean (Glycine max L. Merr) in vegetative growth

This experiment was conducted to investigate the drought tolerance in I 1 genotypes of soybean at vegetative growth stage. The plants cultivated in form of completely randomized blocks design as a factorial with two factors of drought stress and genotype. The factor of genotype had 1 1 levels and the factor of drought stress has 4 levels including control, -3, -7 and -1 I bar soil water potential. The experiment was done in greenhouse of Gorgan University. The water requirement of plants for each irrigation was caclulated with daily scaling of pots and soil moisture curve drawing. The results indicated shoot height, leaf area, dry matter of roots and total plant were significantly reduced under drought stress. The transpiration rate decreased under drought stress, consequently reduction of leaf area (and above ground plant) was more servere than root dry matter. Maintenance of root growth may resulted in the higher water uptake and better adaptation to drought stress. Prolin concentration increased in paints tissues under drought stress. The higher prolin concentration was observed in the more drought tolerant genotypes. However, no significant dependency was found between profit, concentration and other parameters. There was a positive correlation between identified parameters except prolin concentration. Our data indicated that genotypes of sahar, Hill, Dair and Gorgan.-.ʹ the highest drought tolerance. In spiter of low value of all identified parameters in Habit genotype, this genotype was affected less than other genotypes to drought stress and indicated the least of sensitivity index. The most sensitive genotypes were Williams,LBK and BP.