Agronomic response of maize hybrids to water and nitrogen management under diverse climatic conditions of Iran

摘要

This research was performed to evaluate the effects of irrigation regimes (full irrigation, mid water stress,and severe water stress) and levels of nitrogen supply (0, 120, 180, and 240 kg N ha-1) on the agronomic characteristics of three maize hybrids (DC 370, ZP 677, and SC 704). Two field experiments were carried out in Gonabad (in the east of Iran), and Astaneh Ashrafiyeh (in the north of Iran). The highest kernel yield, ear length, rows number/ear, kernels number/row, 100-kernel weight, biological yield, and harvest index obtained from full irrigtion. On the other hand, by decreasing irrigation frequency, most of the parameters were negatively influenced. In both locations, increasing the rate of nitrogen fertilizer increased the kernel yield and yield attributes of maize hybrids in most of the water deficit situations. For most of the measured parameters, 180 kg N ha-1appeared to have the significantly high values than other nitrogen levels. In contrast, kernel yield and yield contributes showed low values in N deficiency conditions.Maize hybrids showed significant differences in regard to measured parameters and SC 704 showed the best results than other hybrids and DC 370 showed lowest kernel yield and other main parameters in either location. Comparison of the two locations revealed that kernel yields obtained from maize hybrids in Astaneh Ashrafiyeh were significantly greater than those obtained in Gonabad. It is concluded that, this result is attributed to the better soil fertility and also favorable weather conditions in Astaneh Ashrafiyeh when compared with Gonabad location