Effects of Diet Composition on the Life-History Traits of Bactrocera Dorsalis (Hendel) (Diptera: Tephritidae)

Abstract

Nutrient acquisition at the larval stage has significant impacts on the development, body weight, and fecundity of fruit flies. In this study, we examined the effects of diet composition on the life-history traits of the oriental fruit fly Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). We reared the flies on four larval diets, namely three artificial diets, which had the main ingredients of sugar, brewer’s yeast, and preservatives; and one fruit-based diet, which had the main contents of ground guava, brewer’s yeast, and preservatives. The three artificial diets had varied yeast-to-sugar ratios (Y:S) of 5:1 in the protein-rich diet, 1.67:1 in the standard diet, and 1:3 in the sugar-rich diet. Differences in development time, pupal weight, adult weight, and fecundity of B. dorsalis were investigated. It was found that the development times of fruit flies on the protein-rich and fruit-based diets were shorter than those on the sugar-rich and standard diets. Pupae and adults in the fruit-based and standard diets were heavier than those from the protein-rich and sugar-rich diets. There was a strong effect of diet on the per-day fecundity whereby the flies in the fruit-based diet had the highest per-day fecundity, while the lowest per-day fecundity was in the sugar-rich diet. The per-day fecundity of the fruit flies on the standard and sugar-rich diets increased gradually from day 1 to day 15, while it decreased in the protein-rich and fruit-based diets.