The hemibiotrophic fungus Colletotrichum kahawae is the causal agent of Coffee Berry Disease - CBD, an economically devastating disease restricted to Arabica coffee production in Africa. Understanding pathogen variability is crucial for the implementation of disease control measures. In this study, six isoenzymatic systems (esterase, acid and alkaline phosphatase, malate dehydrogenase, peroxidase and superoxide dismutase) were used to assess the genetic variation among 12 C. kahawae isolates (from different geographic origins and with different levels of aggressiveness towards coffee) and one Colletotrichum gloeosporioides isolate (not pathogenic to green berries). Cluster analysis of the banding profiles obtained for the six enzymes enabled the differentiation of the two species and revealed the existence of intraspecific variability among C. kahawae isolates. Alkaline phosphatase was the most discriminative enzyme, allowing also the discrimination between the most and least aggressive isolates of C. kahawae.

Sucesso considerável tem sido obtido no uso do melhoramento clássico para o controle de doenças de plantas economicamente importantes, tais como a ferrugem alaranjada das folhas e a antracnose dos frutos do cafeeiro (CBD). Há um grande consenso de que o uso de plantas geneticamente resistentes é o meio mais apropriado e eficaz em termos de custos do controle das doenças das plantas, sendo também um dos elementos chave do melhoramento da produção agrícola. Tem sido também reconhecido que um melhor conhecimento do agente patogênico e dos mecanismos de defesa das plantas permitirá o desenvolvimento de novas abordagens no sentido de aumentar a durabilidade da resistência. Após uma breve descrição de conceitos na área da resistência das plantas às doenças, nesta revisão tentou-se dar uma idéia do progresso na investigação da ferrugem alaranjada do cafeeiro e do CBD relativamente ao processo de infecção e variabilidade dos agentes patogênicos, melhoramento do cafeeiro para a resistência e mecanismos de resistência do cafeeiro.

Considerable success has been obtained in the use of classical breeding to control economically important plant diseases, such as the coffee leaf rust and the coffee berry disease (CBD). There is a strong consensus that growing genetically resistant varieties is the most appropriate cost effective means of managing plant diseases and is one of the key components of crop improvement. It has also been recognized that a better knowledge of both, the pathogens and the plant defence mechanisms will allow the development of novel approaches to enhance the durability of resistance. After a brief description of concepts in the field of plant disease resistance, we attempt to give a view of the research progress on coffee leaf rust and CBD concerned with the pathogens infection and variability, coffee breeding for resistance and coffee resistance mechanisms.