Impact of the pear psyllidCacopsylla pyrihost instar on the behavior and fitness of the parasitoidTrechnites insidious

Pear is one of the most important fruit crops of temperate regions. The control of its mains pest, Cacopsylla pyri , is still largely based on the use of chemical pesticides, with all that this implies in terms of negative effects on the environment and health. Within the context of integrated pest management, innovative and ecologically sustainable strategies must be developed for. Although Trechnites insidiosus is the most abundant parasitoid of C. pyri , its biology and its potential as a control agent have been little studied. In this paper, we conducted experiments to evaluate the behavior of the specialist parasitoid T. insidiosus when exposed to different larval instars of the pear psyllid C. pyri , and to assess the quality of the next generation of parasitoids. We found that although T. insidiosus accepts all host instars for oviposition, the third and fourth instars were the most suitable host in terms of behavioral acceptance and progeny development. Our study is a first step for further studies on the interaction between psyllids and parasitoids and provides evidence that the specialist parasitoid T. insidiosus is a promising candidate for biological control strategies of the pear psyllid C. pyri .