CARLOS ALBERTO RUIZ GARVIA1, HANNES KOENIG2, SEVERIN POLREICH2, GERHARD GEROLD2
1Georg-August-Universität Göttingen, Institute of Agronomy in the Tropics and Subtropics, Germany
2Georg-August-Universität Göttingen, Department of Landscape Ecology, Germany
Cacao (Theobroma cacao) is produced by a small farmer association --El Ceibo-- in the Alto Beni -- Bolivia. These producers depend largely on cacao for their income. In order to promote export of their produce, based on the demand for sustainable and organically produced cacao, farmers have adopted organic certification. No chemical herbicides, insecticides or nematicides are used. However, organic cacao production techniques are difficult to implement and average yields are low compared with conventional cacao.
As a result of high humidity, fungal diseases result in serious yield reductions. Abandoned or mismanaged cacao plantations act as sources of inoculums and there is little cultural control and pruning in productive areas. Previous experiences in others cacao-producing countries have shown promising results from multi-strata canopy management and organic soil fertility maintenance. The use of antagonistic microorganisms for biological control as part of an overall Integrated Pest Management strategy of cacao diseases is given good results. Optimal use of cocoa germplasm and development and distribution of improved pest and disease resistant varieties of cocoa planting materials are only beginning to be explored in the region.
In this study we identified the effects of tropical diseases in cocoa plantations under organic, conventional and agroforestry. Cacao groves were classified according to their management regime. Diseases were characterized and quantified. Most damage was caused by pathogenic fungi, Phytopthora sp. and Crinipellis perniciosa. Continuous removal of diseased pods reduces disease incidence significantly. With this information, we compare strategies toward ecologically and economically sustainable cacao production on small farms.
Keywords: Agroforestry, Bolivia, cacao, certification, Crinipellis sp, diseases, Phytopthora sp., Theobroma cacao