the effect of natural zeolite usage on deficit irrigation stress tolerance in maize (zea mays)

this study was conducted to determine the effect of cliniptilolite natural zeolite on deficit irrigation stress tolerance on maize cultivar ksc704. the experiment was laid out as a factorial design based on randomized complete block with three replications at seed and plant improvement institute, karaj in 2012. four irrigation levels, including irrigation after 70, 95, 120 and 145 mm cumulative evaporation from evaporation pan class a and three zeolite levels including control, 6 and 12 ton /ha were considered as the factors. the effect of irrigation was significant (p< 0.01) for days to silking, asi, ear height, and grain yield and it was also significant (p< 0.05) for days to anthesis, plant height, ear diameter, number of ears and 1000-kernel weight. the using zeolite was significant for 1000 kernels weight and it was significant (p< 0.05) for asi, ear height and grain yield. the maximum yield obtained from normal irrigation and using zeolite 12 ton /ha (7352 and 6134.1 kg / hectare respectively). from the result of this experiment for the maximum grain yield in available water condition for maize cultivar ksc704 irrigation after 70 mm evaporation from evaporation pan can be recommended and this contrition using natural zeolite is not necessary. but in water deficit condition, irrigation after 95 mm evaporation from evaporation pan and using zeolite 12 ton per hectare can be recommended. more deficit irrigation will decrease grain yield significantly.