Influence of intercropping on growth and yield of cassava (Manihot esculenta Crantz)
The research was carried out at the Crops Research Institute Fumesua, Kumasi-Ghana. The Purpose of the study was to determine the response of cassava growth and yield to intercropping, the land productivity of cassava intercropping system and competitive ratio of the cropping pattern. There were seven treatments comprising cowpea, soybean, cassava and maize in association to cassava/cowpea, cassava/soybean and cassava/maize in four randomized complete block design planted in the proportion of 1:1 cassava in the cropping system. In the study, intercropping system gave higher Land Equivalent Ratio (LER) for fresh root yield of 1.28 for cassava/cowpea and 1.06 for cassava/maize. Furthermore, cassava was more productive interms of competitive ratio when it was in association to cowpea, soybean and maize. Cassava root yield ranged from 26 to 36.1 t/ha-1 and the greatest yield was obtained from the cassava/cowpea intercrop which was significantly (P < 0.05) higher than cassava/soybean and cassava/maize. However, maize plant height was relatively higher in intercrop cassava than sole maize. All other treatments effects were not significantly (P > 0.05) affected by the cropping system. Cropping pattern did not significantly affect cob length, number of grains per cob and grain yield. Shoot biomass of cassava was highest in the cassava/cowpea cropping system. When cassava was intercropped with cowpea, soybean and maize, initially the growth of the cassava was affected. When species were in direct competition for limited resources, an increase in yield of one component causes a proportionate decrease in other crop species. Under such situations LER would not likely be significantly greater than 1.0. In the study, such phenomenon would have led to the poor performance of cowpea, soybean and maize yields.
A thesis submitted to the Department of Crop and Soil Sciences, Faculty of Agriculture, College of Agriculture and Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana in partial fulfillment of the requirement for the award of Master of Philosophy Degree in Agronomy, (Crop Physiology), 2015