Ethephon Application and Nitrogen Optimization Through Foliar Urea for Okra Production

To mitigate the environmental impact of excessive urea use, this study investigates the foliar application of urea and ethephon as a more efficient alternative to soil application, aiming to optimize nitrogen use while sustaining the growth and yield of okra. The research was conducted using a randomized complete block design with two factors, replicated four times. Factor A included ethephon levels with a control (E0 = Control, E1 = 150 ppm, E2 = 250 ppm, E3 = 350 ppm), while Factor B comprised two urea levels and a control (U0 = Control, U1 = 1%, U2 = 2 %). The findings revealed significant improvements in evaluated characteristics with the application of ethephon. Among the ethephon levels, E3 produced taller plants with more branches and leaves plant-1. E3 also resulted in higher chlorophyll a, chlorophyll b, and carotenoid content. Additionally, higher fruits plant-1, seeds fruit-1, hundred-seed weight, fruit length, and fresh fruit yield were associated with the E3 level. Among the urea levels, U2 led to improved growth, yield, and photosynthetic characteristics, including fresh fruit yield. The interactive effect of E3 and U2 produced the highest fresh fruit yield of okra. Furthermore, correlation analysis demonstrated significant associations between the evaluated traits, as indicated by the correlation coefficient (R²). The study demonstrated that plant growth regulators like ethephon and urea, when applied via foliar spray; positively impact the yield and related characteristics of okra. Comparative studies on major crops such as maize and wheat are suggested to examine different crops under the influence of foliar application of nitrogenous fertilizers to reduce excessive use and improve fertilizer use efficiency.