In tropical Africa, conservation agriculture practices can address common production constraints on smallholder farms. In Madagascar, scientists Rodenburg et al. combined no-till and cover crops practices during a rice-maize rotation on Striga weed-infested soils. They observed soil nitrogen increments and steep reductions in soil erosion. The yield was moderate for rice but low and variable for maize.
Conservation Agriculture is a promoted form of agriculture, sustaining climate change resilience for smallholder farmers across Africa. However, adoption rates remain low, particularly in Malawi. Scientists Hermans et al. recently revealed a clear distinction between the agro-ecological and socio-economic approaches to conservation agriculture research. They suggested that on-farm trials may help to bridge the two approaches together, leading to better understand what forms of conservation agriculture work, where, for whom and, crucially, why.
The principles of conservation agriculture including minimum soil disturbance, crop residue retention and diversification, have been tested in southern Africa since the early 2000s, but proved insufficient when applied alone. Scientists Thierfelder et al. recently reviewed a bunch of complementary practices needed to make conservation agriculture systems more functional. These include appropriate nutrient management, improved stress-tolerant varieties, the judicious use of crop chemicals, the enhanced groundcover, the increased efficiency of planting and mechanization and an enabling political environment.
Adoption of conservation agriculture in Cambodian smallholder commercial household farms, is a profitable conversion. Scientists Edralin et al. demonstrate that minimum soil disturbance, continuous mulch and cultivation of diverse crop species in space and time improve yield and reduce labor costs. They also show that cover crops and surface mulch significantly reduce manual weeding in all cropping seasons.
