chlorantranilipole and diethyl-maleate

The Asiatice stem borer, Chilo suppressalis (Walker), an important rice insect pest in China, has developed resistances to several classes of insecticides. To control C. suppressalis, chlorantraniliprole has been introduced as a novel insecticide in rice field since 2008. It is an anthranilic diamide insecticide that binds and activates ryanodine receptors (RyR). The susceptibility of field populations of C. suppressalis to chlorantraniliprole was determined in this study. The hypotheses of equality and parallelism showed that regression lines in the tested five populations were neither equal nor parallel. The Ruian, Cangnan, and Liangyungang populations (RA12, CN12, and LYG12) collected in 2012 had lower LD50 values, whereas the Zhuji populations (ZJ12 and ZJ13) collected in 2012 and 2013 were approximately 15 times more tolerant than the RA12 population. To determine the potential mechanisms involved in this tolerance variation, synergism bioassays were performed. Significant differences in susceptibility were found between without synergist and with synergist for the three populations (RA12, LYG12, and ZJ13), based on the tests for the hypotheses of equality. In RA12 and LYG12 populations with chlorantraniliprole, the addition of piperonyl butoxide (PBO) significantly synergized the activity, with synergism ratios of 2.68- and 2.33-fold, respectively, whereas addition of S,S,S-tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM) had no synergist effect. In ZJ13 population with chlorantraniliprole, the addition of PBO and DEF increased synergism ratios by 12.43- and 6.31-fold, respectively, whereas addition of DEM had no significant effect on the toxicity against ZJ13 larvae. These susceptibility and synergism data suggested that detoxification enzymes might be involved in the tolerance variation to chlorantraniliprole in field populations of C. suppressalis.

Topics: Animals; China; Insecticide Resistance; Insecticides; Larva; Maleates; Moths; Organothiophosphates; ortho-Aminobenzoates; Pesticide Synergists; Piperonyl Butoxide; Seasons

The Colorado potato beetle (Leptinotarsa decemlineata (Say)) in the north Xinjiang Uygur autonomous region has evolved resistance to various types of insecticides. Chlorantraniliprole is a novel anthranilic diamide insecticide that binds and activates ryanodine receptors. It exhibited excellent efficacy against L. decemlineata in several field trails in Europe. In the present paper, the susceptibility of L. decemlineata fourth-instar larvae derived from six field populations and L. decemlineata adults derived from three field populations to chlorantraniliprole was determined by a topical application. The fourth-instar larvae were substantially more susceptible to chlorantraniliprole than adults, although the range of susceptibility was far greater among the fourth-instar larvae. Regarding stomach toxicities, adult beetles were less susceptible to chlorantraniliprole than larvae. Chlorantraniliprole was most toxic to second-instar larvae, followed by third- and fourth-instar larvae. These data suggested that the appropriate timing for chlorantraniliprole spraying is the early larval stage. Moreover, the synergistic activities of chlorantraniliprole in combination with triphenyl phosphate, diethyl maleate, or piperonyl butoxide against fourth-instar larvae from two field populations and adults from one field population were tested. Piperonyl butoxide had synergistic effects with chlorantraniliprole against fourth-instar larvae but not against adult beetles. Conversely, triphenyl phosphate and diethyl maleate exerted little synergistic effects. It appears that there is a potential risk of resistance against chlorantraniliprole resulting from cytochrome P450 monooxygenase activity.

Topics: Animals; China; Coleoptera; Cytochrome P-450 Enzyme System; Esterases; Glutathione Transferase; Insect Control; Insect Proteins; Insecticide Resistance; Insecticides; Larva; Maleates; Organophosphates; ortho-Aminobenzoates; Piperonyl Butoxide

In searching for environmentally benign insecticides with high activity, low toxicity and low residue, two series of novel anthranilic diamide containing methyl ether and isopropyl ether group were designed and synthesized. All of the compounds were characterized by (1)H NMR spectroscopy, (13)C NMR spectroscopy and elemental analysis. The single crystal structure of 19j was determined by X-ray diffraction. The insecticidal activities of the new compounds were evaluated. The results showed that some compounds exhibited excellent insecticidal activities against Lepidoptera pests. Among this series, compound, 18l showed 100 % larvicidal activity against Mythimna separate Walker, Plutella xylostella Linnaeus and Laphygma exigua Hubner at the test concentration, which was equal to the available chlorantraniliprole.

Topics: Animals; Diamide; Ethers; Insecticides; Isoxazoles; Larva; Lepidoptera; Magnetic Resonance Spectroscopy; Maleates; Methyl Ethers; Molecular Structure; ortho-Aminobenzoates; Structure-Activity Relationship; X-Ray Diffraction