ارزيابي ژنوتيپ هاي مختلف سويا تحت شرايط تنش خشكي

Evaluation of different soybean (Glycine max L.) genotypes under drought stress conditions

In order to determine drought tolerance indices and the response of soybean genotypes to drought stress, a field experiment was preformed with 15 soybean genotypes using a split plot in randomized complete block design with three replication in 2006 at seed and plant improvement institute, Karaj. Three levels of irrigation 50(normal condition), 100(mild stress) and 150(severe stress) mm evaporation from evaporation pan were considered as the main plot and commercial and promising varieties as the sub plot. In order to evaluation of genotypes to drought tolerance, 9 indices were calculated for yield in hectare. Results showed that genotypes had different response to normal and stress condition. Also, results of biplots analysis and correlation analysis between indices showed that STI, GMP and MP were most suitable indices . After selection of genotypes A and D area in biplots that in each two conditions which had high yield and low yield, respectively based on three introduced indices in three irrigation condition, genotypes as H301, L5P77, S2494G4, M9 and Hamilton had highest yield and they were resistance to drought stress and genotypes as Baj-Maj, Hyl, Br84bijelina and 9242 had lowest yield and they were sensitive to drought stress. Study of cluster analysis results indicated that genotypes in normal condition had low different and this subject made two groups in this trait. But in mild stress, four and in severe stress five groups were observed, that this is because of stress effects on genotypes and response of them to stress.