Effect of Intercropping and Weeding Frequency on The Yield of Beans (Phaseolus Vulgaris L.) and Kale, Cv 'Collards' (Brassica Oleracea Var. Acephala D.C.)

Abstract

Intercropping, the growing of two or more crops on the same piece of land at the same time is practised by most small-scale farmers in high rainfall and semi-arid zones of Kenya. In these zones crops are planted in such a range of combinations under different agronomic practices, that the merits of intercropping against monocropping are often difficult to appreciate. The main objective of this study was to determine if intercropping can be used to minimize the weeding frequencies on beans and kale while maintaining high bean and kale yields. Kale, var. 'Collard' and bean~, cv (GLP2~ were planted at Egerton University Farm, Njoro, during !he 2 seasons of 1999, either in pure stands or in association. Weeding frequencies were no weeding, 1 weeding, 2 weedings, and clean weeded. The experimental design was a split-plot, arrangement in Randomized Complete Block, with three replications. The cropping system formed the main plots, while the weeding frequencies formed the sub-plots. Data were obtained on growth and yield characteristics for both kale and beans. Land Equivalent Ratios (LER) and Cost-Benefit-Ratios were computed using fresh marketable leaf weight of kale and dry weight of bean seed yield. Intercropping significantly (P:S'O.05) reduced rate of leaf production, LAI, number of marketable leaves, and marketable fresh leaf yields in both seasons. Kale unit leaf weight was not affected by intercropping, bu~ was increased by the weeding frequency in both seasons.