The microflora of coffee surfaces and relationships to coffee berry disease

Abstract

Data from previous trials that have been re-evaluated indicate that low levels of coffee berry disease on unsprayed coffee are associated with higher populations of microflora on coffee tissues. Samples were taken at different seasons and altitudes, and from coffee plots receiving different fungicide treatments for the control of coffee berry disease. Although largest populations occurred at the highest altitudes, the relative proportions of microflora components varied with altitude. Fungicides reduced populations of filamentous fungi on all tissues. Trees that had never received fungicide had low populations of Colletotrichum kahawae and had very low levels of coffee berry disease. The disease was also at a lower level on trees that had not been sprayed with fungicides for two seasons where microflora populations were highest. The likely effects of microflora components on coffee berry disease and their potential as biological control agents are discussed.

Keywords:

• Coffee
• phylloplane
• endophytes
• systemic acquired resistance
• microbial biodiversity
• Colletotrichum

Acknowledgements

The authors thank the Coffee Research Foundation, Kenya, University of Reading, UK and the British Council for facilitating the work on which much of this paper is based.