Investigations on thrips of Arabica coffee, Coffea arabica L., 2: Ecological relationships and control of Scirtothrips sweetmani Bianchi

Abstract

The ecological relationships between the control of Scirtothrips sweetmani Bianchi, a coffee pest, are presented. The population was almost the same in coffee trees exposed to sun or medium shade, and was lower in deep shade. Foliage deformations occurred only in the exposed parts. High population levels did not appear to increase leaf dieback. The population increased from July and reached a high level in December. This was followed by a decrease until May, when it increased again. Observations suggest a positive relationship between thrip incidence and bud break, with leaves at the first node having the highest numbers of thrips. Experiments showed that the systemic insecticide Dimecion, alone or in combination with Dieldrin, effected sufficient control when applied twice with a three-week interval between applications. These and other observations indicate that Dimecion may be a promising insecticide for controlling Scirtothrips.