β cypermethrin

The susceptible strain of B. tabaci (MED-S) was sampled in 2009 from damaged poinsettias in the city of Beijing, China (Pan et al., 2011 (link)). All populations were reared on the Gossypium hirsutum cotton plants, maintained at temperature 27 ± 1°C, relative humidity 60 ± 5%, and under a photoperiod with 14:10 h light and dark cycle. Insecticides utilized were analytically standardized. Afidopyropen and sulfoxaflor were purchased from Dr. Ehrenstorfer, Germany. Flonicamid, pymetrozine, imidacloprid, β-cypermethrin, cyantraniliprole, deltamethrin, avermectin, flupyradifurone, chlorpyrifos, dimethyl sulfoxide, and Triton X-100 were purchased from Sigma-Aldrich, Shanghai, China.

D-phenothrin (98% purity) was obtained from Jiangsu Yangnong Chemical Group Co., Ltd., China. Technical-grade permethrin, cyhalothrin, β-cypermethrin, deltamethrin, fenpropathrin, and bifenthrin were purchased from Sigma–Aldrich, United States and high-performance liquid chromatography (HPLC)-grade acetonitrile was purchased from Fisher Scientific, United States. All other chemicals and solvents were of analytical grade. SPs were dissolved in dimethyl sulfoxide (DMSO) or acetone at a stock concentration of 10 g⋅L^-1, and stored in dark bottles at 4°C.
Mineral salt medium (MSM) containing (g⋅L^-1) (NH₄)₂SO₄, 2; MgSO₄⋅7H₂O, 0.2; CaCl₂⋅2H₂O, 0.01; FeSO₄⋅7H₂O, 0.001; Na₂HPO₄⋅12H₂O, 1.5; and KH₂PO₄, 1.5; and Luria-Bertani (LB) medium containing (g⋅L^-1) tryptone, 10; yeast extract, 5; and NaCl, 10 were used in this study. Both culture media were adjusted to pH 7.3 and sterilized at 121°C for 20 min.