Validation of an immigration index for the apple jumping louse Cacopsylla melanoneura in Trentino

The “apple proliferation” disease is an economically important threat for the European apple production and its control relies on the use of insecticides against the vector, Cacopsylla melanoneura. This insect spends a limited period in the apple orchards (late winter - spring, with relevant differences in the years). For this reason a successful control strategy consists in predicting the immigration (from the wood into the orchards) process of the species. In particular, are key points the first appearance in the orchards and the peak of immigration. In 2012 we proposed an Immigration index based on the week average of maximum temperatures and number of hours above a threshold temperature of 9.5°C. Since January 2011 to March 2015 this index has been validated in the field in Valsugana Valley (Trentino). The index proved a strong reliability with high accuracy in predicting both appearance and peak of immigration. It will be employed as supporting tool for the control of C. melanoneura from 201