Biological control in the Maltese Islands - past initiatives and future programmes

Abstract

Past records of introduced predators and parasites for biological control programmes in the Maltese Islands are reviewed. Literature on this subject is very limited, difficult to obtain and to confirm. During the last 10 years, several exotic pest species were accidentally introduced into the Maltese Islands, including Aleurothrixus floccosus, Bemisia tabaci, Liriomyza spp., Frankliniella occidentalis and Phyllocnistis citrella. Natural enemies have been imported to control these pests. These include Dacnusa sibirica and Diglyphus isaea for the control of leafminers; Encarsia formosa, Eretmocerus califomicus and Macrolophus caliginosus for regulation of Bemisia tabaci; Cales noacki against Aleurothrixus floccosus; Orius laevigatus, o. insidiosus and Neoseiulus cucumeris against thrips; Aphidius colemani and Aphidoletes aphidimyza for the control of glasshouse aphids and Phytoseiulus persimilis and Amblyseius califomicus for the control of the red spider mite. Encarsia lutea and Eretmocerus mundus have been recorded from Bemisia tabaci in Malta. Faunistic studies of parasitic Hymenoptera occurring in Malta are currently being carried out. The data is presented and the significance of utilizing local natural enemies is briefly discussed.