Climbing beans reach new heights

Improved varieties of climbing beans are being developed jointly by scientists at the Insitut des Sciences Agronomiques do Rwanda and their counterparts at the International Center for Tropical Agriculture (CIAT), both at its headquarters in Colombia and at their regional office in Africa. Climbing beans can produce up to 1.4t/ha in one season; which is double that of bush varieties; and they are often more disease tolerant. Many farmers grow two crops in one season. In fertile soil beans can climb to more than 3 metres. The most popular climbing bean variety introduced by CIAT from Mexico is the Umubano, which grows well in low phosphorus soils and is resistant to anthracnose; both leaves and red beans are tasty. In Latin America where the beans originated, farmers use maize plants to support the beans. Where maize was not available, researchers were concerned that wood should not be cut to provide staking material and were looking for suitable alternatives. Rwandan farmers, however, have helped to design or identify 15 natural staking materials and crops for supporting climbing beans: these include banana, bamboo and sesbania, as well as branches pruned from eucalyptus and acacia. If farmers are unable to find stakes of the required height, the vines can be wound back down towards the ground. A new staking method currently being evaluated consist of a trellis made of braided banana-leaf ropes hung between poles. CIAT, AA 6731, Cali, COLOMBIAImproved varieties of climbing beans are being developed jointly by scientists at the Insitut des Sciences Agronomiques do Rwanda and their counterparts at the International Center for Tropical Agriculture (CIAT), both at its headquarters in..