Effects of cowpea (<i>Vigna unguiculata</i> L. Walp.) as a Live mulch on weed management in maize cropping

Abstract

Weed interference is a major constraint in maize cultivation. Living mulch as an alternative weed control strategy has been established to be environmentally safe but has not been widely used in maize cultivation. The aim of this research was to evaluate the weed management attributes of Vigna unguiculata in maize cropping. A field study was carried out in the crop garden of the Department of Crop Protection and Environmental Biology, University of Ibadan, Nigeria. The treatments were maize interplanted with Cowpea at 20,000 (M1), 30,000 (M2), 40,000 (M3) plants/hectare, hoe weeding (M4), weedy check (M5) and Primextra-2.5 L/ha (M6). The treatments were arranged in randomized complete block design, each replicated four times. Weed Dry Weight (WDW) and Weed Control Efficiency–WCE (%) were calculated following standardized methods. Data were analysed using descriptive statistics and ANOVA at α0.05. The treatment plots were dominated by weed species in the Asteraceae, Fabaceae and Poaceae families. The M5 accounted for the highest WDW (126.30 g). The WCE was highest in M3 (94.8%) and least in M5 (66.4%). Maize and cowpea interplant at 40,000 plants/hectare suppressed weed. Hence, cowpea is an ideal weed suppressant and can be inter-planted as a cover crop in maize cropping systems.