Effects of drought stress on yield of three common millet (Panicum miliaceum L.) genotypes

Water deficiency has increased the demand for cultivation of drought tolerant crops. In dry regions like most parts of Iran, ecotypes and local varieties often show a high degree of drought resistance. The experiment was arranged in a split plot based on a randomized completely block design that drought stress (50, 75 and 100% field capacity) were considered as main plot and genotype (Rabor, Golbaf and Pishahang) as subplot. The results showed that the traits of leaf water potential, reduction sugar, biological yield and grain yield significantly affected with drought stress at level of 1%. The simple effect of genotype was significant for mentioned traits and photosynthetic pigments. Based on variance analysis, the interaction of genotype×stress was significant only for ion leakage and biological yield. The results of mean comparison showed that drought stress significantly (P≤0.01) decreased biological yield, leaf water content and grain yield, while, ion leakage and reducing sugar contents were significantly increased. The highest biological yield was belonged to Pishahang cultivar in both of normal and stress conditions. Simple correlation among the traits showed that biological yield, relative water content and reduced sugars were the most effective traits on grain yield. In overall, the results showed that Golbaf genotype had the highest grain yield in comparison with Pishahang and Rabor genotypes under water stress conditions.