A temperature-based model for predicting the immigration of Cacopsylla melanoneura and C. picta, vectors of the apple proliferation disease, in South Tyrol, Northern Italy (Hemiptera: Psylloidea)

: Insects in temperate regions usually emerge in spring, based on climatic cues. Temperature-based models that predict the first flight onset of pest insects in crop fields are therefore useful tools for agriculture and crop protection. Here, we calibrate and apply such a temperature-based model for Cacopsylla melanoneura and Cacopsylla picta (Hemiptera - Psyllidae) in South Tyrol, Northern Italy. These psyllid species are the main vectors of apple proliferation, an economically important phytoplasma disease. We found that the temperature associated with the onset (first presence) of the insects in the orchards differs between vectors and between different regions. For the regions Burggrafenamt and Vinschgau, the first adults of Cacopsylla melanoneura remigrants mostly occurred in January while first Cacopsylla picta remigrants mostly occurred in the orchard between March and April. The presented temperature-based immigration model may be used as a tool to predict the first vector appearance in apple orchards in South Tyro