the effect of zeolite on yield and yield components of rapeseed under drought conditions

this study was conducted to analyze the effect of zeolite application on yield and yield components of rapeseed under drought conditions as a factorial-split on the based of randomized complete block design with four replications in 2011-12 in the research field of seed and plant improvement institute, karaj. the effects of zeolite levels z0 (0) and z10 (10 t/ha) under three drought stress levels, control (irrigation after 40%), moderate stress (irrigation after 60%) and severe stress (irrigation after 80% soil water depletion) were in main plots and four genotypes of brassica napus (‘kr4’, ‘eldo’ lines and ‘gkh305’, ‘anatol’ cultivars) were in subplots. based on the results, negative impact of drought on yield components led to a significant fall in grain and oil yield. the most negative impact of drought stress was seen in the grain number per silique. between genotypes, ‘gkh305’ in none stress condition and ‘anatol’ in both mild and severe stress conditions had the highest yield. according to the results, zeolite can be used in growth period or part time of drought stress.