Okra (Abelmoschus esculentus L. Moench) performance as affected by inorganic fertilizer under weed stress conditions

Abstract

Okra is economically and nutritionally valued in the tropics. Sustaining yield is challenging due to declines in soil fertility and labor constraints in weed management. Fertilizers promote crop resilience to field pests, but information on okra's resilience to weed pressure remains limited. This study examined the influence of NPK fertilizer on okra’s tolerance to weed infestation. In 2022 and 2023, a 2×4 factorial experiment evaluated weedy (uncontrolled weed growth) and weed-controlled (Weeded) conditions, alongside four levels of NPK 20-10-10 fertilizer (0, 30, 60, and 90 kg N/ha) in a randomized complete block design with three replicates. The results revealed that fruit weight ranged from 15814.30 (weeded with 0 kg N/ha) to 45994.07 kg/ha (weeded with 60 kg N/ha) in 2022. In 2023, weeding with 60 kg N/ha NPK treatment produced the highest yield. Weeding improved okra survival (77.08%) in 2022 compared to weedy plots (60.88%). Interactions revealed that weedy conditions with 60 kg N/ha had the highest weed cover (73.33% in 2022, 66.67% in 2023), while weeded conditions with 30 kg N/ha had the lowest (38.33% in 2022, 33.33% in 2023). Conclusively, effective weed control combined with 60 kg N/ha NPK optimizes okra growth and survival, while minimizing weed pressure.