effects of water and plant density on grain yield and morphological characteristics of new maize hybrid (cn. ksc.500) in karaj region

in order to evaluate the effects of different levels of water and plant density on yield, yield components, morphological and physiological characteristics of a new corn hybrid (ksc 500), an experiment was carried out in 2006 in karaj area. the experimental design was split plot based on randomized complete blocks design with three replications. main plots were three irrigation levels: 75%, 100% and 125% et and sub plots were three plants densities: 75000, 85000 and 95000 plant per hectare. water requirement was calculate based on soil water limitation to the level of field capacity. the results showed that increasing the levels of irrigation from 75% to 125% et, has a significant effect on yield, plant height, the first ear height above ground, leaf number, leaf width and length, biomass weight, ear length and diameter, number of grain in row, number of row in ear, leaf destruction, 1000 grain weight, 15 ear sample weight, ear wood diameter, grain length, biological yield and harvest index, but its effects on ear wood weight ,tassel length and leaf dry weight was not significant. effect of different densities on yield, plant height, the first ear height above ground, leaf number, leaf length, ear length and diameter, number of grain row, ear wood weight and diameter was significant. according to the results 125% et treatment and 85000 plant per hectare had the best yield (12 ton.ha-1) and 100% treatment in 75000 plant per hectare had the best wue (1.22 kg/m3).