Effects of kaolin in the behaviour of Ceratitis capitata on citrus fruits

Abstract: In this study, we explore the effectiveness of kaolin treatments in protecting fruit from medfly in laboratory tests. Kaolin is a fine-grained aluminosilicate mineral that makes the fruit less suitable for fruit flies oviposition. This study focuses on behavior of medfly on kaolin treated fruits. Orange fruits cv. “Valencia Late” were dipped in a suspension of kaolin. Several doses (1.5%, 2.5%, 3%, 5% and 6%) applied one and two times were tested. Once dried, the color of treated fruit was measured using a Chromameter CR-400 (Minolta, Osaka, Japan). Choice and no-choice experiments were conducted in order to test the kaolin protection against oviposition of C. capitata. In all experiments, 20 mated females per fruit were allowed to oviposit for 5 days. Then, fruits were placed individually into small containers to allow larvae to evolve. The number of larvae per fruit was recorded. In addition, the behavioral response by C. capitata to kaolin treated citrus fruits was studied. Results are discussed and compared with previous findings.