Coffee berry disease (CBD), caused by Colletotrichum kahawae, is a major constraint for Arabica coffee cultivation in Africa. The disease is specific to green berries and can lead to 60% harvest losses. In Cameroon, mixed cropping systems of coffee with other crops, such as fruit trees, are very widespread agricultural practices. Fruit trees are commonly planted at random on coffee farms, providing a heterogeneous shading pattern for coffee trees growing underneath. Based on a recent study of CBD, it is known that those plants can reduce disease incidence. To assess the specific effect of shade, in situ and in vitro disease development was compared between coffee trees shaded artificially by a net and trees located in full sunlight. In the field, assessments confirmed a reduction in CBD on trees grown under shade compared with those grown in full sunlight. Artificial inoculations in the laboratory showed that shade did not have any effect on the intrinsic susceptibility of coffee berries to CBD. Coffee shading mainly acts on environmental parameters in limiting disease incidence. In addition to reducing yield losses, agroforestry system may also be helpful in reducing chemical control of the disease and in diversifying coffee growers' incomes.

In the high altitude regions of Africa, coffee berry disease (CBD), caused by Colletotrichum kahawae, is the main constraint for arabica coffee (Coffea arabica) production. However, certain agricultural practices can reduce losses caused by the disease and thereby promote optimum production. On small family farms in Cameroon, mixed cropping with fruit trees, intercropping with food crops and maintenance pruning of coffee trees are very widespread agricultural practices that can affect CBD epidemics. Consequently, an epidemiological study was conducted to assess how cultural practices affected the disease in an arabica coffee smallholding in Cameroon. The disease was monitored on a weekly basis over four successive years (2002)(2003)(2004)(2005) on coffee trees in diverse cultural situations. Cultural practices likely to reduce losses due to CBD were identified. The infection rate was significantly lower on coffee trees grown intensively than on coffee trees grown in the traditional manner. Coffee trees located under the shade of fruit trees were significantly less attacked than those located in full sunlight. In addition, berries on the leafless parts of branches, near the main trunk of the coffee tree, were less infected than those on leafy sections. These results show that maintenance pruning, removal of mummified berries, and mixed cropping with shade plants are cultural practices which create environmental conditions that limit CBD development.

A study was conducted in Barombi-kang, in the forest agro-ecological zone with mono modal rainfall pattern in Cameroon to evaluate the adaptability of selected NERICA upland rice varieties and their response to fertilizer application. A factorial split plot experimental design in a randomized complete block with three replications was used. The first factor included: T0 (unfertilized control), T1 (200 kg NPK / ha + urea 100 kg/ha) and the second factor included 7 varieties of rice namely NERICA 1, NERICA 2, NERICA 3, NERICA 4, NERICA 8, NERICA 10 and Fofifa. Varieties tested were well adapted to the mono modal rain forest agroecological zone. Thus, average cycle duration was 100 days and grain yield ranged between 1.4 and 2.3 t/ha without fertilizer use. Yield and yield components were significantly (p<0.05) enhanced by fertilizer application particularly grain yield (146%), grain per panicle (59%), straw yield (50%). Highly significant correlations (p<0.05; r = 0.60 to 0.90) were observed between grain yield and most of the yield components. Further studies are warranted to address the yield gap existing between farmers' practice and on-station research before disseminating these varieties to farmers.