Organic resource management in banana-based cropping systems of the Lake Victoria Basin, Uganda

Abstract

The cultivation of plantain and cooking banana in humid areas of Uganda continues to grow in importance as rural population densities increase and as demand from urban areas intensifies. Difficulties accompany this importance, particularly soil depletion and intensification of pests and diseases of banana. We interviewed 510 farm families practising banana-based cultivation in six districts along the Lake Victoria Basin of southern-central Uganda to determine which resource management strategies are undertaken to mitigate limitations to banana cultivation and the importance of livestock and intercropping within those systems. Of the farmers interviewed, 97% reapply banana stalks and leaves to the banana mats on pruning and upon harvest, a practice that may contribute to banana weevil, stem nematode and sigatoka fungal attacks. Banana stalks were also applied as mulches to cash (4%) and field crops (2%) and used as livestock feed (10%). Farmers applied a wide range of additional resources to bananas including field crop residues (81%), burned residues (3%), on-farm manures (31%), compost (16%), external organic (17%) and chemical (4%) inputs. Of the organic inputs applied to bananas, bean trash (72%), maize stover (68%), cattle manure (45%) and composts (18%) were most frequently applied. It was necessary to consider at least five different organic inputs to account for more than 90% of farmer practices. Overall, intercropping was practised by 69% of the farmers. The six most encountered intercrops were, in decreasing order, beans, maize, cassava, Ficus nataliensis and fruit trees. When organic matter management was separated into five general categories depending on the reliance upon bananas, other crops, manures and composts as organic additions to soils, significant differences in reported average bunch weights were obtained. The farmers applying banana stalks, field crop residues and cattle manures reported the largest bunch weights (20.3 kg per bunch). Farmers relying upon banana stalks alone, banana stalks with field crop residues and either small livestock manure or domestic compost reported the lowest yields (13.1, 14.3 and 12.9 kg per bunch, respectively). We conclude that farmers are developing strategies to resist fertility depletion, in part through better recycling of on-farm resources and intercropping but greater reliance upon external inputs may be required to ameliorate declining banana yields.