Effects of Time of Weed Removal and Cropping system on Weed Control and Crop Performance in Okra/Amaranthus Intercrop

Abstract

A field trial was conducted during the late wet seasons of 2011 and 2012 at the Research Farm of the Federal University of Agriculture, Alabata, Abeokuta (7015’N, 3025’E) in the forest savanna- transition zone of Ogun State, South Western Nigeria. The objective was to evaluate the effect of time of weed removal and cropping system on weed control and crop performance in okra/amaranthus intercrop. The experiment was laid out in a Randomized Complete Block Design (RCBD) in a Split- plot arrangement. The treatments consisted of three main plots and five sub plots replicated three times. The main plot treatments were single hoe- weeding at 3 weeks after planting (WAP), double weeding at 3 & 6 WAP and no weeding, while the sub plots consisted of okra intercropped with amaranthus at 0.5g/m2or 1.0g/m2, okra sole and amaranthus sole at 0.5g/m2 or 1.0g/m2. Results from the study showed that intercropping of okra with amaranthus reduced weed infestation significantly (p<0.05) compared to sole okra. Weed control treatments significantly (p<0.05) reduced weed infestation in the intercrop while cropping system did not have any significant effect (p<0.05) on the weed biomass, plant height, pod length, number of pods and pod fresh weight. Uncontrolled weed infestation led to 50.7% yield loss in okra. It is therefore concluded that intercropping of okra with amaranthus is an effective means of reducing weed pressure in okra production as well as increasing land productivity.