Performance evaluation of spirodiclofen, spirotetramat and carboxymethyl cellulose-B for management of Cacopsylla pyri

The pear psyllid [Cacopsylla pyri (L.), (Hemiptera: Psyllidae)] represents one of the most economically significant pests of pear in Serbia and worldwide. It causes direct damage throughout feeding on young stems and leaves, but also creates favourable conditions for the development of plant diseases. In this article susceptibility of C. pyri to spirodiclofen, spirotetramat, and their combinations with foliar fertilizer (carboxymethyl cellulose-boron, CMC-B) was investigated in order to assess their efficacy. Experiments were conducted in accordance with standard OEPP/EPPO methods, in field trials on two localities in the Republic of Serbia (Kula, Vrbas), during 2020/21. Results of the field trials indicate good efficacy for all variants in pear psyllid control in pear orchards. The high efficacy of spirodiclofen (87.4-95.4%), spirotetramat (82.5-91.8%), spirodiclofen + CMC-B (90.3-99.8%), spirotetramat + CMC-B (89.5-96.8%) was achieved at both localities seven days after treatment during 2020/21 field trials. Also, it can be concluded for examinations 14 days after treatment, where the efficacy of spirodiclofen (84.9-92.0%), spirotetramat (81.2-91.7%), spirodiclofen + CMC-B (88.9-97.5%), and spirotetramat + CMC-B (82.3-92.5%) was high at both of investigated localities. Based on the obtained results it can be concluded that the high efficacy of the researched insecticides is a good indicator of C. pyri susceptibility in pear orchards.