Wasp guardians for food production
A representative of the genus Metaphycus, which includes parasitoids that prey on numerous scale-insect species, like the serious pest of olive tree, Saissetia oleae. Credit - Evangelos Koutsoukos.
Chalcid wasps serving as guardians of food production in Cyprus
Chalcid wasps comprise one of the most diverse, species rich, and ecologically significant groups of arthropods (a type of invertebrate or animal with an exoskeleton). They can be found in both natural and man-made habitats, and while most species are parasitoids (defined below), some species are phytophagous plant pests, feeding on plants.
Parasitoids are organisms who, through living as larvae in other organisms, kill their ‘host’ as they grow. Numerous parasitoid chalcid wasps are associated with serious agricultural and horticultural insect pests, regulating their populations. Nevertheless, globalisation and world-wide trade of goods has led to the translocation of various insect pests far from their native range increasing their severe socioeconomic consequences to global food production. Chalcid wasps (and other parasitoid groups) have been used as a more ecologically friendly alternative to chemical insecticides, which have been increasingly found to impact native biodiversity such as pollinating insects. While parasitoids cannot fully replace traditional pest management methods, they can still contribute to integrated pest management efforts.
"We aim to fill knowledge gaps regarding chalcid wasps occurring in both natural and man-made habitats in Cyprus, and their role to the delimitation of insect pest species."
As such, many chalcid wasp species have been utilised against both native and alien pests by plant protection authorities. Some have been even introduced far from their native range for pest control management schemes. Apart from their deliberate introduction as biocontrol agents, in recent decades there are numerous occasions where parasitoids have followed their host-insects to newly invaded areas (as alien species). Both native and introduced parasitoids have been a main subject of research to ensure adequate and uninterrupted food production. However, parasitoids and their role in pest management remain largely understudied.
Research has shown that more than 200 species of chalcid wasps occur in Cyprus, of which 64 are non-native. Seventeen of these species have been deliberately introduced as biological control agents with their vast majority (82%) being introduced against various pests that severely affect Citrus production, such as the citrus leaf miner (Phyllocnistis citrella). Other chalcid wasp species have been introduced against the serious olive pest (Saissetia oleae) and the potato crop pest (Phthorimaea operculella). Apart from these species, parasitoid complexes that attack other major crop pests in Cyprus are pretty much unknown.
During the two year project, ‘Species richness and biological invasions of Chalcid wasps in Akrotiri Peninsula,’ we will be carrying out material surveys in order to increase our knowledge of biodiversity, biological invasions, and impacts of Chalcid wasps in the Akrotiri peninsula, and within Cyprus in general. With this project, we aim to fill knowledge gaps regarding chalcid wasps occurring in both natural and man-made habitats (including in crops) in Cyprus, and their role to the delimitation of insect pest species.
Written by Evangelos Koutsoukos and Jakovos Demetriou. For more information on this Darwin Plus Main project DPLUS202, led by Wildlife Conservation Society (WCS), please click here.