The status of Aleurocanthus spiniferus from its unwanted introduction in Italy to date.
Aleurocanthus spiniferus (Quaintance) (orange spiny whitefly, OSW) (Hemiptera Aleyrodidae) has been spreading in Puglia Region since its first report in Italy in 2008. The pest has gradually invaded the whole Lecce District thus expanding northward into Brindisi District. The pest will soon invade the citrus orchards on the Ionic Basilicata coast thus threatening the major Italian citrus orchards in Calabria and Sicily. The aleyrodid also threatens the national and international trade in plants and plant products because of the Quarantine status (EPPO A2) of the species. OSW is a major pest of Citrus; we also report more than thirty other host plant species belonging to twenty-two families infested by this pest; thus, cultivated and urban areas, parks and protected natural reserves are infested to varying degrees. Moreover, it disturbs natural and protected habitats, also forcing unwanted pesticide use in economic and recreation areas as in private gardens. Small-scale results of pesticide use are also discussed with special attention to citrus orchards. Soft soaps and wetting agents gave incomplete pest control while neonicotinoids (Imidacloprid) disrupt Aleurothrixus floccosus (Maskell) parasitoids complex eliciting secondary pest resurgence. Classical Biological Control (CBC) is forbidden in Europe by the Habitats Directive 92/43/EEC and in Italy by transposed regulations (DPR 357/1997, DPR 120/2003). Augmentative Biological Control (ABC) chances are discussed on the basis of trials to discover candidate effective indigenous natural enemies. Finally, we consider the OSW biocontrol in non-economic area as the most promising action in order to lower the pest pressure in orchards and, thus, the rise of pesticide-tolerant or -resistant pest strain.