Evaluation of the Performance of Climbing and Bush Beans as Sole Crops and When Intercropped With Maize: A Case Study of Kyangyenyi Sub-County, Sheema District
Abstract
This study evaluated bean production strategies for hilly agro-ecologies in East Africa, where smallholder farmers must balance productivity, climate resilience, and economic viability. Climbing and bush bean cultivars were compared under sole cropping and maize intercropping systems in Sheema District, Uganda. A randomised complete block design with three replications was conducted over two growing seasons. Five treatments were evaluated: (1) Sole Climbing bean, (2) Sole Bush bean, (3) Climbing bean-maize intercrop, (4) Bush bean-maize intercrop and (5) Sole Maize. Data were collected on growth, yield components, intercrop efficiency - land equivalent ratio (LER), and economic returns. Climbing beans produced significantly higher sole-crop yields (4,416.7–5,138.9 kg/ha) than bush beans (1,750–2,416.7 kg/ha; p < 0.01), with Cost- Benefit Ratio of 32.24 and 10.11, respectively. However, climbing bean–maize intercropping showed poor compatibility (LER = 0.54) and reduced maize yield by 84.5%. In contrast, bush bean–maize intercropping achieved higher land-use efficiency (LER = 1.61) and reduced maize yield by only 35.3%. Sole climbing beans generated the highest returns (UGX 19.99 million/ha) but required about 30% more labour and additional staking costs, whereas bush bean–maize intercropping generated UGX 6.57 million/ha with lower input requirements. Seasonal variability strongly influences crop performance: prolonged rains increased climbing bean yield by 16.4% but reduced bush beans by 27.6%, attributed to waterlogging and snail damage. Generally, the findings demonstrate that optimal bean production strategy depends on farmer circumstances: Sole Climbing Beans maximises yields for resource-endowed farmers, while Bush bean-maize intercrops offer risk-averse smallholders more sustainable production. These evidence-based results provide concrete recommendations for crop improvement, extension services, and agricultural policy in East African highland farming systems.