O presente trabalho teve como objetivos, avaliar o efeito de diferentes densidades de plantio e regime hídrico na incidência e severidade da cercosporiose do cafeeiro e correlacionar o progresso da doença com enfolhamento, produtividade e variáveis climáticas. O ensaio foi conduzido em Lavras, MG, com a variedade Rubi de 3 anos. Os tratamentos constituíram-se de 5 densidades de plantio: 2.500, 3.333, 5.000, 10.000 e 20.000 plantas/ha; e cafeeiros irrigados e não irrigados, com 4 repetições. As avaliações foram realizadas a cada 15 dias de dez.2003 a dez.2004 em 8 folhas por planta no terço médio de 8 plantas da unidade experimental. O regime hídrico e as densidades de plantio atuaram isoladamente na incidência e severidade da cercosporiose. A irrigação diminuiu a incidência e severidade da cercosporiose, com os menores valores de incidência encontrados nas densidade de 10.000 e 20.000 plantas/ha. Com relação à produtividade nas densidades de 3.333, 5.000 e 10.000 plantas/ha os cafeeiros não irrigados foram mais produtivos devido a bienalidade e a maior produtividade foi observada na densidade de 20.000 plantas/ha. As variáveis climáticas de temperatura mínima, média e máxima e precipitação tiveram correlação negativa com a incidência e severidade da doença nas densidades de 2.500, 3.333 e 5.000 plantas/ha.
The effect of 5 planting densities (2,500; 3,333; 5,000; 10,000 and 20,000 plants ha-1) and water regime (irrigated and not irrigated plants) was evaluated on incidence and severity of brown eye spot in coffee trees. The impact of climatic factors associated with leafing of the plants and crop productivity levels on disease progress curves was also assessed. The experiment was conducted in an experimental area at Universidade Federal de Lavras (UFLA), with three-year-old coffee trees (Coffea arabica L.), var. Rubi. The experiment was set in a randomized block design with four replications, in a split-plot scheme. The treatments in the plots consisted of planting densities and in the subplots was the water regime. The incidence and severity evaluations of brown eye spot on the leaves were carried out each fifteen-day from Dec. 2003 to Dec. 2004. It was also evaluated the percentage of leafing of the plants and the coffee tree productivity. It was verified that the incidence and severity brown eye spot were not influenced by the interaction among the treatments. The lowest values of incidence and severity were observed in the 10,000 and 20,000 planting density in irrigated plants. The highest crop productivity was observed in the 20,000 planting density in not irrigated plants. This can have been resulted of the biennial oscillations that occur in the production, characteristic of the coffee trees. The incidence of brown eye spot was negatively correlated with the maximum, medium and minimum temperature and with the precipitation in the lowest planting densities (2,500, 3,333 and 5,000 plants ha-1).
