Evaluation of yield, yield components and water content of four grain corn hybrids in different levels irrigation

To study the effect of different irrigation levels on yield, yield components and water percent of grain corn varieties, an experiment was conducted in a split plots experiment based on randomized complete blocks design with three replications in Agriculture research station of Ilam University. Irrigation in four levels (Irrigation after 70, 105 and 140 mm evaporation in evaporation pan class A) were considered as main plots and four grain corn hybrid (SC 704, SC 677, SC 666 and SC 524) assigned to subplots. Results from analysis of variance showed that variety×irrigation interaction effect were not significant on studied traits, but the effect of irrigation levels on grain yield, biological yield, harvest index, 100 grain weight, grain number per rows and ear length and diameter were significant and on the number of rows in ear and plant water percent were not significant. Also, differences among hybrids were significant for grain yield, number of row per ear, 100 grain weight, biological yield, ear diameter and plant water percent. Grain yield in I70 (10306.5 kg.ha 1) was more than the other irrigation levels. The number of grain per row was the crucial yield component led to 19% and 42% decreasing of grain yield in I105 and I140, respectively. Among evaluated hybrids in this experiment, SC 677 (8820.7 kg.ha-1) and SC 524 (7784.7 kg.ha-1) had the highest and lowest grain yield, respectively. Furthermore, the maximum number of rows per ear and the maximu 100 grain weight were observed in SC 704 and SC 524, respectively.