Controllo biologico degli insetti in foresta: passato, presente e futuro

After a brief description of the procedures to follow when planning operations for the protection of trees in forests and the advisability of using biological pest control in such systems, we take a look at the most significant and successful measures adopted in Italy starting from the mid-nineteenth century using native, insectivorous insects to limit important forest phytophages. The research conducted on the introduction, breeding and release of exotic, insectivorous insects of phytophages, also exotic, is subsequently described. Such discussion also dedicates due space to the presentation of the results of studies performed to ascertain the role of the volatile substances released by the plants in mediating the relations occurring in nature between the plant hosts, their phytophages and antagonists of the latter. The possible measures to take in order to overcome the obstacles currently making breeding, multiplication and storing of insectivorous insects onerous are also investigated. Lastly, reference is made to the issues, highlighted in many spheres of research, related to the introduction and liberation of exotic antagonists into the pre-existing system of the local entomofauna and on the degree of appreciation expressed by public opinion on biological pest control in general