BACKGROUND Pymetrozine is a valuable novel insecticide for control of sucking insects, including the brown planthopper Nilaparvata lugens (Stål), one of the most serious pests on rice. This study was conducted to elucidate the action mechanisms of pymetrozine on the feeding behaviour of the planthopper. RESULTS The activity test showed that pymetrozine primarily functioned as an antifeedant t...

BACKGROUND Vector-borne plant disease management can be enhanced by deployment of antifeedants in addition to the use of broad-spectrum neurotoxic insecticides. The effects of pymetrozine on Asian citrus psyllid (ACP), Diaphorina citri Kuwayama, feeding behaviour, survival and transmission of Candidatus Liberibacter asiaticus (Las), the presumed causal pathogen of huanglongbing, were investigat...

Pymetrozine is a compound that interferes with insect feeding and interrupts transmission of plant pathogens. The glassy-winged sharpshooter, Homalodisca coagulata Say (Hemiptera, Cicadellidae), is a vector of Xylella fastidiosa, the foregut-borne, propagative bacterium that causes Pierce's disease of grapevine. In this study, we recorded the behavioral response of H. coagulata to plants treate...

Pymetrozine is a neuroactive insecticide but its site of action in the nervous system is unknown. Based on previous studies of symptoms in the locust, the feedback loop controlling the femur-tibia joint of the middle leg was chosen to examine possible targets of the insecticide. The femoral chordotonal organ, which monitors joint position and movement, turned out to be the primary site of pymet...

Residues of the polar pesticide pymetrozine were compared using two methods: hydromatrix and liquid-liquid extraction (LLE). The biological half-life and the final residue level were investigated using Aster scaber over a 10-days cultivation period. The respective biological half-lives of the pesticide were 4.2 and 3.5 days at the recommended and double dose. The final residue levels were 1.28 ...

The toxicity of three insecticides to Lysiphlebus fabarum (Marshall) (Hymenoptera: Braconidae: Aphidiinae), a parasitoid of Aphis fabae Scopoli (Hemiptera: Aphididae), was investigated using IOBC/wprs protocols. Abamectin 1.8 EC, imidacloprid 350 SC, and pymetrozine 25 WP were tested under laboratory conditions at recommended field rates. Immature stages of the parasitoid were exposed to materi...

The implementation of an Integrated Pest Management (IPM) program requires selecting and using chemicals which are least harmful to natural enemies. In this study, the acute toxicity of the recommended field concentration of four conventional insecticides was evaluated in reference to the different life stages (L3, L4 and adult) of the variegated lady beetle Hippodamia variegata (Goeze) (Coleop...

BACKGROUND Insecticide resistance in Trialeurodes vaporariorum W. is unknown in the species' northern distribution range where it inhabits mainly commercial greenhouses. Resistance development in whiteflies feeding on year-round crops in greenhouses is possible owing to the use of chemical treatments to back up biocontrol. The authors tested the response levels to spiromesifen, pymetrozine and ...

Insect predators in North America suppress Aphis glycines Matsumura (Hemiptera: Aphididae) populations; however, insecticides are required when populations reach economically damaging levels. Currently, insecticides used to manage A. glycines are broad-spectrum (pyrethroids and organophosphates), and probably reduce beneficial insect abundance in soybean, Glycine max (L.) Merr. Our goal was to ...

Ensembles of neuronal networks and sensory pathways participate in controlling the kinematic and dynamic parameters of animal movement necessary to achieve motor coordination. Determining the relative contribution of proprioceptive feedback is essential for understanding how animals sustain stable, coordinated locomotion in complex natural environments. Here, we focus on the role of chordotonal...