A LAND MANAGEMENT BASED APPROACH TO INTEGRATED STRIGA-HERMONTHICA CONTROL IN SUB-SAHARAN AFRICA

Striga hermonthica, an obligate root parasite of grasses, is one of th e most severe constraints to cereal production in sub-Saharan Africa. In the recent past, prior to increased production pressure on land, S. hermonthica was controlled in African farming systems by prolonged cr op rotations with bush fallow. Because of increasing need for food and concomitant changes in land management practices, however, these fall ow rotations are no longer extensively used. Shorter crop rotations an d fallow periods have also led to declines in soil fertility which pre sent a very serious threat to African food production. A sustainable s olution will be an integrated approach that simultaneously addresses b oth of these major problems. An integrated programme that replaces tra ditional bush fallow rotation with non-host nitrogen-fixing legume rot ations, using cultivars selected for efficacy in germinating S. hermon thica seeds, is outlined, The programme includes use of S. hermonthica -free planting material, biological control, cultural control to enhan ce biological suppressiveness, host-plant resistance, and host-seed tr eatments.