Evaluation of the effect of different irrigation intervals on some agronomic characteristics of domestic and foreign corn (Zea mays L.) hybrids in the region of north of Khuzestan

Background and objectives: one of the aspects of managing the maize, like any other crops, is determine the plant cultivar and irrigation interval for using the cultivar potential. one of the most important problems in corn cultivation in the northern region of Khuzestan is low information of farmers about grain yield and some agronomic characteristics of domestic and foreign corn hybrids in this region and this factor lead to difficulties in the decision of farmers to select suitable hybrids for cultivation. also water consumption is high in corn, thus this study was carried out to evaluate the reaction of domestic and foreign corn hybrids available in response to difefrent irrigation intervals.
Materials and Methods: This experiment was carried out on the basis of split-plot design in completely randomized block design with three replicates in 2015. Irrigation treatments in three levels includes 7, 14 and 21 day’s interval) as main-plot that applied in flowering(tassel emergence) and available hybrids in region in nine levels includes Moghan704, Jovin704, Mobin 616, Karoon 701, NS770, Simon, BC582, BC678 and AS71 as sub-plot were carried out. The characteristics measured were yield and grain yield components (number of kernel rows, number of kernels per row, 1000-kernel weight), plant height, number of leaves per plant, plant diameter, length and width of ear leaf, ear length.
Results: Results showed that the effect of irrigation treatments, hybrid and irrigation×hybrid interactions on grain yield, 1000-kernel weight, ear length and number of kernels per row was significant. The effect of hybrid and irrigation×hybrid interaction on number of kernel rows was significant. Mean comparison of irrigation×hybrid interactions on grain yield showed that the highest amount of grain yield was observed in Moghan704 in 7 day (1.18 kg/m2) and 14 day (1.14 kg/m2) intervals, Jovin 704(1.23 kg/m2) in 7 day intervals, Simon in 7day (1.15 kg/m2) and 14 day(1.2 kg/m2) and NS770 in 7 (1.2 kg/m2)and 14(1.27 kg/m2) day interval and the lowest amount of grain yield was observed in Mobin 616 in 21 day interval(0.54 kg/m2) and Karoon 701 in 21 day intervals(0.62 kg/m2). Mobin616 hybrid had the highest number of kernel rows in 7 day intervals (14.9) and Simon had the lowest amount in 21 day interval (12.4). NS770 had the highest number of kernels per row in 14 day intervals (43.9)) and Mobin616 had the lowest amount in 21 day interval (28.06). BC582 hybrid had the highest ear length in 14 (21.9) and 21 day intervals (22.06) and Mobin616 had the lowest amount in 21 day interval (15.5). Simon had the highest plant height (260.16 cm). Mobin hybrid had the highest leaf number (15.6). Simon hybrid had the highest leaf length (89.3 cm). In terms of leaf width, BC678 had the highest amount (9 cm).
Conclusions: 7-14 days irrigation interval can be applied after corn tasseling and achieved grain yield similar to 7 days. But irrigation interval more than 14 days is not recommended because cause a significant decrease in the grain yield.