Intensity of Leaf Rust Disease on Four Robusta Coffee Clones in Natar, South Lampung

Abstract

Lampung Province is the producer and exporter of coffee in Indonesia. Leaf rust disease is an important disease in coffee and is caused by fungus Hemileia vastatrix Berk& Br. This disease has spread to all coffee cultivation areas worldwide, including Indonesia. The incidence of this disease can cause production losses and reducing productivity up to 50%. The aim of the study was to determine the intensity of leaf rust disease in four Robusta coffee (Coffea canephora) clones in Natar, South Lampung Regency, Lampung Province, namely BP 436, BP 534, BP 939 and SA 203. The experiment was conducted in a completely randomized block design, with four clones, 30 replicates, and 30 evaluation samples. The intensity of disease attacks was calculated using Townsend-Heuberger formula. The results indicated that the intensity of disease attack on four clones was classified as a mild attack, with the lowest attack level was on BP 534 clone (5.63%). Robusta coffee is relatively tolerant to leaf rust disease, however management of this disease must be applied to prevent greater yield losses.