Evaluation of performance of rice (Oryza sativa) and taro (Colocasia esculenta) in a mixed cropping system

Abstract

Taro (Colocasia esculenta (L) Schott var. esculenta) is widely distributed and cultivated in the wet tropics of the world. In Ghana, its cultivation is limited to river basins or banks in large cities. However, a few farmers grow it on a large scale and rank it as their main source of income. A major problem identified in its production is the flooded culture that makes its cultivation intensive and expensive, and the seasonality in marketing the crop. This necessitated the introduction of rice into the cropping system to increase productivity per unit area and increase income of farmers. To facilitate technology transfer and adoption of this technique, an integrated approach was used. The participatory research–farmer–extension approach is described. Rice growth measure, as height, tiller and effective tiller counts were not significantly influenced in the system. Rice growth was better on the rotation and intercrop plots. Although rice height, tillers and effective tillers were higher for the intercrop system, yields under this system were lower because of the negative correlations that exist between rice height, tillers, and grain yield. Taro growth measured as petiole length and leaf number increased with time on all systems; the rate of increase was higher for sole crop than the intercrop system. Rice reduced taro petiole length and increased leaf number in the intercrop. Tuber sizes were the same for all treatments, but final taro yields were reduced. The average performance of the rice crop in the intercrop was the same (0.85), whilst that of taro varied within the study period, giving values of 1.35 – 1.5. The taro crop (1.65) was found to be more competitive or aggressive than rice (0.6) in the intercrop system. The intercrop had LER values of 1.1 and 1.2, signifying a better option in terms of land resource use.

Ghana Journal of Agricultural Science Vol. 37 2004: 49-57