Evaluation of Yield and Yield Components of Facultative and Winter Bread Wheat Genotypes (Triticum aestivum L.). under Different Irrigation Regimes in Khorasam Province in Iran

摘要

To evaluate drought tolerance of 20 genotypes of bread wheat under different irrigation regimes, a strip plot experiment based on a complete randomized block design with 3 replications was conducted for 2 growing seasons (1998-2000). Main plots were allocated to 3 levels of irrigation namely 10 days (AJ, 20 days (A_2) and 30 day (A_3) intervals. Sub plots were allocated to 20 genotypes of winter and facultative bread wheat. Grain yield, total biomass, number of spike m~(-2), harvest index and 1000 kernel weight significantly affected by irrigation treatments and therefore negative responses were more pronounced by increasing irrigation intervals. Water use efficiency was higher for 2o days irrigation interval compared with other treatments. Grain yield, biological yield and number of spikes m~(-2) were higher for C-75-6, C-75-10 and C-75-16 genotypes for all treatments. However when a 20 and 30 days irrigation interval were applied, grain yield, number of spike m~(-2), harvest index and water use efficiency for C-75-14 and C-75-9 genotypes were higher. These genotypes were more flexible under drought condition. They were relatively early maturing and had relatively higher number of spike m~(-2) and also higher harvest index and water use efficiency.