https://doi.org/10.37229/fsa.fja.2024.06.25

Two field experiments were conducted at the research farm of the sustainable development center of the New Valley resources in Kharga Oasis, New Valley Governorate, Egypt (25.52° N and 30.61° E) during the growing seasons of 2022 and 2023. To study the effect of both sowing date and plant density on maize productivity, water use efficiency, and fall armyworm infestation rate. The results showed that planting density and time have a significant impact on maize's vulnerability to fall armyworm infestations, as well as its productivity and water-use efficiency over the course of the two growing seasons. The findings indicated that maize productivity peaked when maize was planted on August 15, with a plant density of 150,000 plants/ha, where it recorded 10.21 and 10.26 t/ha during two growing seasons, respectively. The incidence of autumn armyworm was lowest, at a plant density of 50,000 plants/ha and with late planting on August 15, reaching 5.48 % and 3.23% throughout the two growing seasons, respectively. The intermediate density of 100,000 plants/ha with August 15 sowing offers a balanced approach, providing favorable yields (9.17-9.31 t/ha) with moderate infestation (11.67-12.33%) and high WUE (1.68-1.70 kg/m³). This combination may represent the most sustainable option for farmers seeking to balance multiple production objectives.