Distribution and reproductive biology of Dacus persicus (Aak fruit fly); a pest of Calotropis gigantea in Sri Lanka

Abstract

Calotropis gigantea is a native plant in Sri Lanka having medicinal value. It is recorded as an invasive plant in Australia, Brazi, USA, etc. Dacus persicus larvae feed on C. gigantea seeds and influence directly to reproductive output of the plant making it a suitable candidate of bio-controlling. Present study therefore aimed to study the distribution and reproductive biology of D. persicus to assess the potential of it as a bio control agent for Calotropis species. D. persicus was recorded in eight provinces out of nine provinces in Sri Lanka. Mating and ovipositing time of D. persicus was 53.80(± 1.68) and 92.31(± 2.62) minutes respectively. Fruit-fly eggs were found in inner pericarp layer of Calotropis fruits. Only a single cluster was found in a fruit with 18.5(±0.847) eggs which hatched within 2.87 (± 0.62) days. Infected fruit consisted of 11.91(±1.27) larvae and 7.04(±1.13) cocoons. Larval and cocoon periods were 20.15(± 2.11) and 11.72(±0.26) days respectively. These results provide baseline information needed in adopting D. persicus as a bio control agent of C. gigantea.