Response of maize productivity to nitrogen fertilizer and spraying with blue green algae extract

The main purpose of this investigation was to evaluate the impact of nitrogen fertilizer and spraying with blue green algae extract levels on the productivity of maize. Two field experiments were conducted at private farm at Algraydh Village, Bialla district, Kafrelshiekh Governorate, Egypt during 2017 and 2018 seasons. The treatments were allocated in a strip-plot design with four replications. The vertical-plots were devoted to nitrogen fertilizer levels (60, 80, 100 and 120kgN fed-1). While, the horizontal-plots were assigned to spraying with blue green algae levels (without as control, 1.5, 3.0, 4.5 and 6.0g L-1). Increasing fertilizer levels up to 120kg N fed-1 significantly exceeded other levels of nitrogen fertilizer and produced the highest averages of growth characters, yield and grain quality, followed by using 100kg N fed-1 and there is no significant differences between them in most studied growth characters and yields in both seasons. Foliar spraying with 6.0g L-1 significantly surpassed other treatments and recorded the maximum averages of growth, yield and its components and grains quality of maize, followed by spraying plants with 4.5g L-1 and without significant differences between them in all studied characters in both seasons. Generally, mineral fertilizing maize with 100kgN fed‑1 (saved 20kgN fed‑1) beside spraying with algae extract at 4.5g L-1 were recommended for enhancing productivity and seed quality of maize moreover, reducing the pollution resulted from high levels of mineral nitrogen fertilizer under the environmental conditions of Kafrelshiekh Governorate Egypt.