Toxicity and Sublethal Effects of Diamide Insecticides on Key Non-Target Natural Predators, the Larvae of Coccinella septempunctata L. (Coleoptera: Coccinellidae).

Coccinella septempunctata (ladybird) is an extremely important natural predator that feeds on aphids. An assessment of the toxicity of pesticides on environmental organisms is an essential component of Integrated Pest Management (IPM) strategies. This study evaluated diamide insecticides' toxicity at lethal and 30% lethal doses (LR30) against C. septempunctata larvae. The pre-imaginal median lethal doses (LR50) of chlorantraniliprole 10% SC, tetrachlorantraniliprole 10% SC, and broflanilide 10% SC were calculated to be 42.078, 289.516, and 0.0943 g active ingredient (a.i.)/ha, respectively. The mortality tests demonstrated that chlorantraniliprole and tetrachlorantraniliprole are comparatively less toxic to C. septempunctata than broflanilide, which were detected to be highly toxic to C. septempunctata. The mortality rates of the groups treated with the three diamide insecticides tended to stabilize after 96 h, extending to the pre-imaginal stage. Furthermore, when compared to broflanilide, which had a much higher potential risk, the hazard quotient (HQ) values indicated that chlorantraniliprole and tetrachlorantraniliprole have a lower risk potential for C. septempunctata in farmland and off farmland. The LR30 dose induces abnormalities in the development phase 4th-instar larvae weight, pupal weight, and adult weight of treated C. septempunctata. The study emphasizes the importance of assessing the adverse effects of diamide insecticides on natural predator species that serve as biological control agents in agricultural IPM strategies.

Absolute configuration of four chiral isomers of pyrisoxazole and their bioactivity.

BACKGROUND: Pyrisoxazole is a fungicide that has two chiral carbon atoms and four isomers: (3S,5R)-, (3R,5S)-, (3S,5S)-, and (3R,5R)-pyrisoxazole. RESULTS: Pure crystals of four pyrisoxazole isomers were prepared by chiral separation and single-crystal cultivation. Their absolute configurations were established by X-ray single crystal diffraction analysis. Bioassays indicated that compound (3S,5R)-pyrisoxazole showed excellent fungicidal activity with a median effective concentration (EC50 ) value of 0.14 µg mL-1 and protective activity with an EC50 value of 13.29 µg mL-1 . These values are superior to the commercial fungicides boscalid and racemic pyrisoxazole. CONCLUSIONS: The biological activity of racemic pyrisoxazole is due almost exclusively to the isomer (3S,5R)-pyrisoxazole; the other three isomers had very low activity. © 2020 Society of Chemical Industry.

(E)-2-[(4-Chloro-1,3-dimethyl-1H-pyrazol-5-yl)methyl-eneamino]benzamide.

In the title compound, C(13)H(13)ClN(4)O, the dihedral angle between the aromatic rings is 33.47 (9)° and an intra-molecular N-H⋯N hydrogen bond generates an S(6) ring. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds occur, resulting in R(2) (2)(8) loops.