Weed Interference in Passionfruit Cultivation: Determinants of Growth Under Water and Nutrient Stress in Baixada Fluminense

Abstract

Yellow passionfruit (Passiflora edulis) accounts for 90% of Brazil’s national production, yet its shallow root system makes it highly vulnerable to weed competition. This study evaluated the effects of Panicum maximum interference, water stress, and nutrient limitation on passionfruit seedling growth under greenhouse conditions. A 2×2×2 factorial design was used, with treatments combining presence/absence of weeds, water restriction (50% vs. 80% field capacity), and nutrient limitation (25% vs. 200% recommended fertilization). Soil moisture was monitored via pot weighing, and growth parameters were assessed. Results demonstrated that weed competition significantly reduced passionfruit development, particularly under concurrent water and nutrient stress. Seedlings in weed-free treatments with adequate resources (200% nutrients, 80% field capacity) showed 40% greater biomass compared to stressed conditions. Water limitation alone reduced leaf area by 30%, while nutrient restriction alone impaired root growth by 25%. The combined stress of weeds, low water, and low nutrients led to a 60% decline in overall plant vigor, highlighting synergistic negative effects. These findings emphasize the critical need for weed control during orchard establishment, especially in resource-limited regions like Baixada Fluminense. Optimizing irrigation and fertilization can mitigate weed interference, enhancing passionfruit productivity. This study provides actionable insights for tropical fruit farming and aligns with global goals for sustainable agriculture.