Effects of insecticide application interval on Aphis gossypii (Glover) population in Capsicum frutescens A S Rejeki, Firdaus, A D Nasruddin, and A Nasruddin1*
Hasanuddin University
Abstract
The purpose of the current study was to determine the effect of different insecticide application intervals on the population density of the cotton aphid, Aphis gossypii (Glover). The field experiment was arranged in a randomized complete block in factorial design. The first factor was spray interval: 3 days, 7 days, and 14 days. The second factor was the insecticide active ingredient: spinetoram and carbosulfan. Each treatment combination had four replications of a plot each. From each plot, four plants were selected to determine the number of aphids (nymphs and adults) per leaf. The results showed that each of the insecticide application intervals had significantly fewer aphids than the control (unsprayed plots). However, the numbers of aphids among the spray intervals were not significantly different each other. This means that spraying plants every 14 days was as effective as spraying them every three days. The result suggested that farmers should use 14 days interval instead of three days interval as they currently practice in managing the cotton aphid. By doing that, insecticide use could be cut by 75%. Our results also showed that spinetoram was more effective than carbosulfan in controlling A. gossypii. Carbosulfan is considered not environmentally friendly and its use in agriculture has been banned in more than 60 countries, including USA and the European Union. Thus, spinetoram can be used to substitute carbosulfan for the control of the cotton aphid.
