title: Susceptibility of Sogatella furcifera and Laodelphax striatellus (Hemiptera: Delphacidae) to Six Insecticides in China.
abstract: The whitebacked planthopper, Sogatella furcifera (Horváth), and small brown planthopper, Laodelphax striatellus (Fallén), both are important crop pests throughout China, especially in rice. Application of chemical insecticides is the major control practice. Consequently, insecticide resistance has become an urgent issue. In this study, resistance levels to six conventional insecticides were evaluated for these two species collected from major occurring areas of China. Additionally, imidacloprid- (resistance ratio [RR] = 10.4-fold) and buprofezin (RR = 15.1-fold)-resistant strains of whitebacked planthopper were obtained through laboratory selections for cross-resistance profiling and synergism assessment to understand resistance mechanisms. The results showed that all tested populations of both species exhibited low to high levels of resistance to chlorpyrifos, while remaining susceptible to thiamethoxam. Three of the 14 whitebacked planthopper populations showed low to moderate resistance to imidacloprid, while all small brown planthopper populations reminded susceptible. All small brown planthopper and whitebacked planthopper (except one) populations showed at least moderate resistance (RR = 10.1-271.1) to buprofezin. All small brown planthopper populations remained susceptible to pymetrozine and nitenpyram, and all whitebacked planthopper populations remained susceptible to isoprocarb. The imidacloprid-resistant whitebacked planthopper strain showed no significant cross-resistance to other tested insecticides. However, the buprofezin-resistant strain exhibited a low-level cross-resistance (CR = 3.1) to imidacloprid. Piperonyl butoxide, triphenyl phosphate, and diethylmaleate displayed no synergism effect on the resistant whitebacked planthopper strains.
authors: Key Laboratory of Integrated Management of Crop Diseases and Pest, Department of Pesticide Science, College of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China. Jiangsu Area Huaiyin Institute of Agricultural Science, Huai'an 223001, China.
authors: Kai
authors: K
authors: Zhang
authors: Key Laboratory of Integrated Management of Crop Diseases and Pest, Department of Pesticide Science, College of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China.
authors: Wei
authors: W
authors: Zhang
authors: National Agro-Tech Extension and Service Center, Beijing 100026, China.
authors: Shuai
authors: S
authors: Zhang
authors: Key Laboratory of Integrated Management of Crop Diseases and Pest, Department of Pesticide Science, College of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China.
authors: Shun-Fan
authors: SF
authors: Wu
authors: State Key Laboratory of the Discovery and Development of Novel Pesticide, Shenyang Research Institute of Chemical Industry Co., Shenyang 110021, China.
authors: Lan-Feng
authors: LF
authors: Ban
authors: Key Laboratory of Integrated Management of Crop Diseases and Pest, Department of Pesticide Science, College of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China.
authors: Jian-Ya
authors: JY
authors: Su
authors: Key Laboratory of Integrated Management of Crop Diseases and Pest, Department of Pesticide Science, College of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China. gaocongfen@njau.edu.cn.
authors: Cong-Fen
authors: CF
authors: Gao
mesh_terms: D000818:Animals; D002681:China; D006430:Hemiptera / Q000187:drug effects* / Q000254:growth & development; D007305:Insecticide Resistance; D007306:Insecticides / Q000494:pharmacology*; D009758:Nymph / Q000187:drug effects / Q000254:growth & development; D013045:Species Specificity
chemical_list: D007306:Insecticides
keywords: Laodelphax striatellus; Sogatella furcifera; buprofezin; imidacloprid; resistance monitoring