SIZE AS A FACTOR IN THE MATING PROPENSITY OF MEDITERRANEAN FRUIT-FLIES, CERATITIS-CAPITATA (DIPTERA, TEPHRITIDAE), IN THE LABORATORY

We show that body size of nonirradiated, laboratory-reared Mediterranean fruit flies, Ceratitis capitata (Wiedemann), is an important factor in mating success. With pupal weight as the estimate of size, 8- and 9-mg flies were optimum in mating success, followed in decreasing order by 6- and 4-mg flies. Mating frequency was generally reduced when females were larger than males. However, mating frequency was generally equal when males were of equal or larger sizes than females. The percentages of adults eclosing, flying, and mating, as well as mating speed were positively correlated with increasing pupal size. Relevance of these data to a final analysis of the sterile-insect technique (SIT) phase of the California Mediterranean Fruit Fly Eradication Program is discussed along with suggested practical application for use in future SIT programs against C. capitata. A table of wing measurements is also provided for correlation of wing dimensions (length and width) to pupal weight (mg) for trapped wild C. capitata as a basis for size determination of sterile insects to be used in an eradication program.