Biologia e diffusione di Halyomorpha halys, l’autostoppista invasivo che sconvolge la difesa integrata

Biology and spread of Halyomorpha halys, the invasive hitchhiker that disrupts integrated pest management Halyomorpha halys is an invasive fast-spreading pest of global importance native to East Asia, currently reported in the United States, Canada, Chile and Europe. Its bioecological features favour the human-assisted worldwide spread as a hitchhiker on inanimate objects by any means of transport and make its management in the field very difficult. H. halys causes severe damage to many crops and in Northern Italy it quickly became key-pest of fruit orchards, resulting in an increase in the number of treatments with broad spectrum insecticides, seriously disrupting previous IPM programs. The great success of this invasive species seem to be related to: i) the wide range of suitable host plants, both cultivated and spontaneous; ii) the great mobility of all instars; iii) the very high growth rate potential (in Northern Italy, R0 = 24.04 and 5.44 for the overwintering and summer generation, respectively); iv) the scarcity and very low efficacy of the native biocontrol agents; iv) the strong association with human beings, especially during the overwintering period, that, beside making it a household nuisance pest, highly facilitates the diffusion through traveling people and goods.