The Colorado potato beetle (CPB; Leptinotarsa decemlineata) is an important potato pest with known resistance to pyrethroids and organophosphates in Czechia. Decreased efficacy of neonicotinoids has been observed in last decade. After the restriction of using chlorpyrifos, thiacloprid and thiamethoxam by EU regulation, growers seek for information about the resistance of CPB to used insecticides and recommended antiresistant strategies. The development of CPB resistance to selected insecticides was evaluated in bioassays in 69 local populations from Czechia in 2017-2022 and in 2007-2022 in small plot experiments in Zabcice in South Moravia. The mortality in each subpopulation in the bioassays was evaluated at the field-recommended rates of insecticides to estimate the 50% and 90% lethal concentrations (LC50 and LC90, respectively). High levels of CPB resistance to lambda-cyhalothrin and chlorpyrifos were demonstrated throughout Czechia, without significant changes between years and regions. The average mortality after application of the field-recommended rate of lambda-cyhalothrin was influenced by temperature before larvae were sampled for bioassays and decreased with increasing temperature in June. Downwards trends in the LC90 values of chlorpyrifos and the average mortality after application of the field-recommended rate of acetamiprid in the bioassay were recorded over a 6-year period. The baseline LC50 value (with 95% confidence limit) of 0.04 mg/L of chlorantraniliprole was established for Czech populations of CPBs for the purpose of resistance monitoring in the next years. Widespread resistance to pyrethroids, organophosphates and neonicotinoids was demonstrated, and changes in anti-resistant strategies to control CPBs were discussed.

• MeSH
• brouci * účinky léků   MeSH
• dursban * farmakologie   MeSH
• insekticidy * farmakologie   MeSH
• larva účinky léků   MeSH
• neonikotinoidy * farmakologie   MeSH
• nitrily farmakologie   MeSH
• pyrethriny farmakologie   MeSH
• rezistence k insekticidům * MeSH
• Solanum tuberosum parazitologie   MeSH
• thiamethoxam MeSH
• thiaziny * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika MeSH
• Názvy látek
• cyhalothrin MeSH Prohlížeč
• dursban * MeSH
• insekticidy * MeSH
• neonikotinoidy * MeSH
• nitrily MeSH
• pyrethriny MeSH
• thiacloprid MeSH Prohlížeč
• thiamethoxam MeSH
• thiaziny * MeSH

The cabbage stem flea beetle (CSFB), Psylliodes chrysocephala (Coleoptera: Chrysomelidae), has recently become a major pest species in winter oilseed rape in the Czech Republic. The susceptibility of CSFB populations from two localities to six pyrethroids, two neonicotinoids, one organophosphate and one oxadiazine was evaluated in 2015-2018 in glass vial experiments. The susceptibility of CSFB to thiacloprid and thiamethoxam was evaluated in feeding experiment in 2017 and 2018. High susceptibility of CSFB populations to lambda-cyhalothrin, cypermethrin, esfenvalerate, tau-fluvalinate, etofenprox, deltamethrin, chlorpyrifos, indoxacarb and acetamiprid was observed in the glass vial experiments. The LC50 and LC90 data obtained for pyrethroids in these experiments in 2015 represent baseline for CSFB resistance monitoring to pyrethroids in the Czech Republic. High tolerance of CSFB to thiacloprid of CSFB was demonstrated in glass vial and the feeding experiment, too.

• MeSH
• Brassica parazitologie   MeSH
• brouci účinky léků   patogenita   MeSH
• insekticidy toxicita   MeSH
• neonikotinoidy toxicita   MeSH
• pyrethriny toxicita   MeSH
• rezistence k insekticidům * MeSH
• thiaziny toxicita   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• insekticidy MeSH
• neonikotinoidy MeSH
• pyrethriny MeSH
• thiacloprid MeSH Prohlížeč
• thiaziny MeSH