Performance of Maize and Beans under Castor-Based Intercropping System

Castor (Ricinus communis L.) has attracted a lot of attention all over the world as a potential crop targeting on-farm biofuel production. In Kenya smallholder farmers are already growing castor with maize (Zea mays L.) and beans (Phaseolus vulgaris L.) under an intercrop system in spite of the limited knowledge that such a system would have on growth and yield. The aim of this research was to investigate the possible effect of castor-based intercropping system on the performance of maize and beans. A 3 × 3 × 2 factorial experiment randomized in complete block design with three levels of crops, three levels of cropping system and two levels of spacing was laid-out at Egerton University farm, Njoro campus; for three seasons in 2010 to 2012. Results at P =.0001 level of significance indicated high seed yield for castor monocrops ranging from 2.0 - 3.0 tons seeds ha-1 yr-1 while castor with beans intercrop were shown as the best intercrop combination with resultant yields levels reported in the range of 2.15 - 2.43 and 0.3 - 0.83 tons seeds ha-1 yr-1 for an intercrop of castor (1.5 m × 1.0 m) with beans (0.5 m × 0.2 m) respectively. In contrast, castor with maize intercrop gave low maize grain yield of between 0.0 – 0.25 tons ha-1 yr-1. It was concluded that castor could be grown successfully with beans without straining food crop production. In addition an intercrop of castor with maize and beans would not have significant effect on the yield performance of castor