Sowing and fertilization strategies to improve maize productivity

Field experiment was conducted to examine the impacts of two sowing dates (8 April - first date of sowing and 21 April - second date of sowing) and four nitrogen rates (0, 60, 120 and 180 kg ha(-1)) on the productivity of maize hybrid 'ZP 434' in the Pannonian region of Serbia during 2016 and 2017 seasons. The dry period during late vegetative development and grain filling stage in 2017 decreased ear traits, grain yield, starch and oil contents, nitrogen agronomic (NAE) and nitrogen use efficiency (NUE). The highest number of grains per ear, starch and oil contents, starch and oil yields and lower rainfall use efficiency (RUE) and protein content were obtained from the early sowing date. The ear traits, grain yield, RUE, protein content, oil content and yield of starch, protein and oil significantly increased while NAE, NUE and starch content significantly decreased with increasing nitrogen rate. The results indicated a significant inverse correlation between starch and protein contents, which prevents the improvement of these two parameters simultaneously. Thus, timely sowing and nitrogen input should be used as long term management strategies for increasing maize yield and grain quality.