Influence of the hosts Planococcus citri and Planococcus ficus on oviposition,development, sex ratio and survival of Leptomastix dactylopii

Abstract: Leptomastix dactylopii Howard (Hymenoptera: Encyrtidae) is a koinobiontendoparasitoid of several mealybug species and is often effectively used as a biological controlagent of the citrus mealybug, Planococcus citri (Risso) (Hemiptera: Pseudococcidae), in citrusorchards and ornamental greenhouses. Leptomastix dactylopii has also been used in vineyards tocontrol the vine mealybug, Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), withunsatisfactory results, probably due to the low host suitability or vineyard microclimaticconditions.In order to investigate the P. ficus suitability as host for the parasitoid, no-choiceexperiments were carried out by exposing L. dactylopii females, obtained from two separaterearing lines on P. ficus or P. citri, to third-instar nymphs and young adult females of eitherP. ficus or P. citri. The number of parasitized mealybugs as well as developmental time, numberof male and female offspring, sex ratio, offspring longevity, body size of maternal line femalesand body size of female offspring were recorded.The host species did not affect the developmental time, adult longevity and sex ratio of theparasitoid offspring. However, L. dactylopii females reared on P. ficus produced significantly lessoffspring, which were also smaller in size than those reared on P. citri.The results of this study suggest that both P. ficus and P. citri are suitable hosts for thedevelopment of L. dactylopii.