Timing and Frequency of Spraying for Control of Coffee Leaf Rust in Southern India

Abstract

SummaryTo study control of Hemileia vastatrix leaf disease in Coffea arabica L., an experiment was run for a year in Coorg District of Mysore State. Three and four early-season sprays coupled with two mid-season ones gave a reasonable control, as evaluated by leaf spot counts, but a high proportion of rust-affected leaves were retained on the bushes. Infection commenced in the hot weather, immediately after showers, and the number of infected leaves appears to have been more important than the average leaf spot counts. Control of leaf disease up to December, and a late incidence of the rust during January, may not affect crop prospects appreciably. It is suggested that reduced early sprays coupled with pre-monsoon and timely mid-season schedules should reasonably control the incidence of rust.