In a review of their own research the authors summarize incidences and distributions of the most important fungal diseases in Ethiopia and progress in breeding for resistance. Ethiopia, as the centre of origin for Coffea arabica, hosts a large diversity of germplasm. The incidences of diseases are based on observations in the montane rainforests of the southeast (Harenna) and southwest (Bonga, Berhane-Kontir, Yayu) of Ethiopia.

Coffee (Coffea spp.) is one of the world's most valuable agricultural export commodities produced by small‐scale farmers. Its germplasm, which holds useful traits for crop improvement, has traditionally been conserved in field genebanks, which presents many challenges for conservation. New techniques of in vitro and cryopreservation have been developed to improve the long‐term conservation of coffee. But a question remains as to whether these new techniques are more cost effective than field collections and more efficient at reducing genetic erosion. This study compared the costs of maintaining one of the world's largest coffee field collections with those of establishing a coffee cryo‐collection at the Centro Agronómico Tropical de Investigación y Enseñanza (CATIE) in Costa Rica. The results indicate that cryopreservation costs less (in perpetuity per accession) than conservation in field genebanks. A comparative analysis of the costs of both methods showed that the more accessions there are in cryopreservation storage, the lower the per‐accession cost. In addition to cost, the study examined the advantages of cryopreservation over field collection and showed that for species that are difficult to conserve using seeds, and that can only be conserved as live plants, cryopreservation may be the method of choice for long‐term conservation of genetic diversity.

No abstract

No abstract

Pathogenicity tests were performed on 11 genotypes of Coffea arabica using single‐isolate suspensions of Colletotrichum Kahawae obtained from 90 monoconidial isolates. The objective of this study was to estimate the proportion of pathogenic variation corresponding 10 differences in aggressiveness and virulence (races). A large part of the variation in the pathogen population was due to aggressiveness. The differential effects were too small to suggest conclusively that races exist. This paper discusses the possible causes for the observed small differential interaction and suggests breeding strategies that not only prevent possible adaptation of the pathogen to resistant varieties but also limit variation for resistance due to differences in aggressiveness of the pathogen.