Smallholders' use of stylosanthes for sustainable food production in subhumid West Africa

The subhumid zone of West Africa has 180-270 growing d and receives 900-1 500 mm of rainfall. The zone is covered mainly with ferruginous tropical soils that hâve very low levels of N and P and a low cation exchange capacity. The common farming System is crop-livestock, with a prédominance of cash crops wherever thèse hâve been introduced. The genus Stylosanthes, which originated mainly in South America, was tested in West Afhca as early as thé 1940s in an attempt to improve livestock nutrition and soil fertility. Some of thé major attributes explaining thé success of mis genus are tolérance to thé fun gal disease anthracnose, adaptation to infertile soils, drought résistance, ability to fix N without spécial Rhizobium inoculum, and high seed yield. Intégration of Stylosanthes into thé West African farming Systems intensified with thé opening of thé International Livestock Centre for Africa's subhumid research site in Kaduna, Nigeria, in 1978, and since then thé genus has been exploited to suit thé dômes tic needs of various countries. The management Systems included sole crops of Stylosanthes ("fodder banks") to supplément natural range or improved grass-legume and légume-légume associations. Stylosanthes has also been successfully integrated in crop rotations as an intercrop and relay crop. Tremendous variation occurs in thé research-development efforts and diffusion of Stylosanthes in thé West African région. For instance, in Nigeria, this légume is ex ploited by smallholders for agropastoral herds, small ruminants, and crop production. More recently, thé concept of mixed cover crops involving Stylosanthes was introduced, and évidence suggests that such a management System leads to more profitable and sustainable crop-livestock production Systems. In Cameroon, a lot of potential exists for thé expansion of Stylosanthes-based enterprises into agropastoral herds, but thé smallholders hâve not fully exploited such benefits. This is mainly because on-farm research and extension are in their infancy in this région. In Côte d'Ivoire, thé use of Stylosanthes has been geared toward thé dairy industry through thé Eco-farms Project, a scheme jointly spon sored by thé African Development Bank, Gesellschaft fur Technische Zusammenarbeit (or ganization for technical coopération), and thé Ivorian govemment. The aim has been to enable smallholders to générale incomes équivalent to those of their counterparts in thé cities. In Mali, Stylosanthes could improve cereal production and thé performance of traction animais. Some constraints to adoption, such as lack of labour and capital, plant disease, in sufficient quantities of seed, and thé expense of fencing, eut across ail thé four countries studied; other problems are spécifie to individual countries. The land-tenure constraint af fecting agropastoralists, for instance, is more acute in Nigeria. In Côte d'Ivoire, pasture management is a serious problem in thé Eco-farms where Stylosanthes is grown in associ ation with aggressive grasses. Also, thé scheme is too capital intensive. In Cameroon, thé weak support for on-farm research and extension is unique, whereas in Mali, thé successful cotton industry is providing capital for Stylosanthes adoption. The potential of Stylosanthes for feed improvement, land réclamation, and control of noxious weeds should be further exploited by integrating thé légume in crop rotations and promoting it to farmers with more profitable enterprises, such as those involving beef cattle, dairy cattle, traction animais, and cotton. Other measures recommended for thé long-term sustainability of Stylosanthes Systems include thé establishment of an adéquate seed supply, identification of highly pro ductive and disease-resistant varieties, use of live pôles (for example, Ficus) for fencing, and thé use of draft power. Government policies that promote loan schemes and protect land rights are also needed.