One of the negative consequences of globalization is the increasingly frequent introduction of exotic pests into new distribution areas. The establishment of these alien species in new environments is also favoured by climate change. Italy, in particular, is at high risk of introduction, because of its geographical position and climate, which allows the adaptation of exotic species, even subtropical. The mechanisms involved in adaptation processes, crucial in studies of biological invasions, are known only in part. It is therefore needed a joint effort by groups operating in Italy and abroad to counter this phenomenon and to develop appropriate strategies for sustainable control of alien species. The present Program GEISCA (Globalization Exotic Insects Sustainable Control Agro-forestry ecosystems) has been developed in this context. It is specifically targeted at the sustainable control of introduced exotic species, especially (but not exclusively) with respect to the action exerted against them by native entomophagous insects. The Program involves seven research units operating in different Italian regions. These units will work in collaboration also with international research organizations, because, even if the project is primarily of interest for Italy, the problem of sustainable control of alien species can not and should not be addressed solely on a national scale. The species considered are all of great interest for crop protection. Some have been established in the Italian territory (and not only) for some years and are producing damage to host plants and the environment whereas others, more recently arrived, must be studied to try to counteract their spread in an environmentally friendly manner.
Dryocosmus kuriphilus (Asian chestnut gal wasp -ACGW), of Chinese origin, was reported in Italy in 2002 and is considered, worldwide, one of the most damaging pests of chestnut. Tuta absoluta, (South American tomato moth), has been reported in Italy in 2008 and is very harmful mainly to tomato crops. For both species, the goal is to increase knowledge about new associations with native natural enemies in different areas of the country. For ACGW, an objective is also the study of the relationship between the introduced exotic parasitoid Torymus sinensis and native parasitoids. Drosophila suzukii (Spotted wing Drosophila – SWD) is an invasive species of Asian origin, reported in Trentino in 2009 and then in almost all Italian regions. SWD is harmful to fruit ripening of many crops and wild plants. For this species, research on the association with entomophagous insects will be undertaken. Another goal is the identification of attractants and useful tools for sampling SWD. Two xylophagous species will be also studied, namely the long horn beetles Anoplophora glabripennis (in Italy since 2009) and Psacothea hilaris (recorded in 2005). The aim is to find the complex of native parasitoids that can be associated to the two exotic species. For P. hilaris further studies regarding its biology, fundamental for a correct development of control strategies, are also necessary. Similarly, the investigations of interactions with native parasitoids is the goal of the research involving the leafminer moths Phyllocnistis vitegenella, Antispila oinophylla and Coptodisca sp. Another species that is considered is the harlequin ladybird Harmonia axyridis, an active predator of aphids, no longer produced by most European commercial insectaries because of its invasiveness. For this species the aim is, firstly, to increase knowledge about the interactions with indigenous parasitoids and, secondly, to study some factors that influence its spread into new distribution areas. With regard to the alien thrips (already present or at risk of introduction), the objective is, on the one hand, make samplings on their presence in citrus orchards in Calabria, secondly to evaluate the presence and the role of indigenous antagonists. Finally, the eucalyptus psyllid Glycaspis brimblecombei will be studied. We want to define the guild of natural enemies of this species and their role, with particular reference to the exotic Psyllaephagus bliteus (Hymenoptera Encirtidae) that was not artificially introduced, but anyway was found in Italy in 2011.
The overall objective of the program is to have, at the end of three years, useful knowledge on the development of appropriate procedures for sustainable control of target species, avoiding that our Peninsula act as a bridge for the spreading of non-native insect species harmful to other European and Mediterranean countries.