Host plant preference by the papaya mealy bug, Paracoccus marginatus (Hemiptera: Pseudococcidae) on selected host Plants under laboratory condition

The papaya mealy bug, Paracoccus marginatus has invaded Sri Lanka in 2008 that attacks many host plants, including economically important tropical fruits, vegetables and ornamentals. None of the insecticides has given complete control of the pest and hence, Acerophagus papayae an endo-parasite of P. marginatus was introduced to Sri Lanka in 2009 from Puerto Rico. The parasitoid has recorded more than 90% control of the pest in the locations where the parasitoid was released. This pest has established as a major pest of papaya in the Island at present. Out-breaks of the pest has been reported time to time in certain locations. Therefore, need has aroused for mass rearing and release of the parasitoid to the infested areas during pest out-breaks. Present studies aimed at selecting a more economical and effective host plant than potato for mass rearing of P. marginatus under laboratory conditions. Development time, survival percentage, preference of the different developmental stages of the pest on four different host plants, Hibiscus rosasinensis, Jatropa curcas, Codiaeum sp. and Ipomoea batatas were studied. Lowest developmental time of different nymphal stages, was on Jatropha curcas and Hibiscus rosa-sinensis plants. Highest survival percentage and highest preference observed from the nymphs reared on Jatropha
and Hibiscus plants.