The Influence of Host Fruit and Temperature on the Body Size of Adult Ceratitis capitata (Diptera: Tephritidae) under Laboratory and Field conditions

Abstract

The adult body size of the Mediterranean fruit ßy, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), varies in natural conditions. Body size is an important Þtness indicator in the Mediterranean fruit ßy;largerindividuals are more competitive at mating and have a greater dispersion capacity and fertility. Both temperature during larval development and host fruit quality have been cited as possible causes for this variation.We studied the inßuence of host fruit and temperature during larval development on adult body size (wing area) in the laboratory, and determined body size variation in Þeld populations of the Mediterannean fruit ßy in eastern Spain. Field ßies measured had two origins: 1) ßies periodically collected throughout the year in Þeld traps from 32 citrus groves, during the period 2003Ð2007; and 2) ßies evolved from different fruit species collected between June and December in 2003 and 2004. In the lab, wing area of male and female adults varied signiÞcantly with temperature during larval development, being larger at the lowest temperature. Adult size also was signiÞcantly different depending on the host fruit in which larvae developed. The size of the ßies captured at the Þeld, either from traps or from fruits, varied seasonally showing a gradual pattern of change along the year. The largest individuals were obtained during winter and early spring and the smallest during late summer. In Þeld conditions, the size of the adult Mediterannean fruit ßy seems apparently more related with air temperature than with host fruit. The implications of this adult size pattern on the biology ofC. capitata and on the application of the sterile insect technique are discussed.