Action of the ecdysteroid agonist tebufenozide in susceptible and artificially selected beet armyworm

Abstract

: Toxicity assays with tebufenozide, the Ðrst commercial non-steroidal ecdysteroid agonist, against a laboratory strain of the beet armyworm, Spodoptera exigua (Hu bner), demonstrated the promise of this new compound for the control of this important pest. Experiments to select insects artiÐcially from the laboratory strain by continuous exposure of larval instars to corresponding LC 25 doses of tebufenozide for over 12 generations 14È15 months), (G 0 ] G 12 : revealed no loss in susceptibility to the insecticide for up to Ðve generations. Moreover, retention and fate of 14C-labelled tebufenozide were investigated using larvae from the selection experiments and the results compared with G 6 those for the susceptible larvae. In addition, piperonyl butoxide, an inhibitor (G 0 ) of monooxygenases, when ingested by larvae along with tebufenozide, increased the susceptibility of intoxicated larvae to this ecdysteroid agonist, indicating its oxidative metabolism in Spodoptera larvae.1998 Society of Chemical ( Industry.

Toxicity of ethyl acetate extract and ricinine from <i>Jatropha gossypifolia</i> senescent leaves against <i>Spodoptera exigua</i> H&uuml;bner (Lepidoptera: Noctuidae)

“…26) Hence, for practical application, the use of crude extract may be better than using an isolated compound because ricinine is toxic to mammals 27) and crude extract may have other active compounds that can interact and synergize 5 of ethyl acetate J. gossypifolia extract by the dipping method, for which the control group was 70% ethanol. (1) After monitoring the components from eluted solution using TLC, 20% dichloromethane:hexane could be separated into two fractions (I and II); similarly, 70% dichloromethane:hexane could be separated into two fractions (II and III). each other to increase control effectiveness against S. exigua.…”

“…Due to heavy selection pressure over the past two decades, the pest has developed resistance to various insecticides in many countries. [1][2][3][4] Recently, in order to circumvent this problem, several biopesticides have been developed. Among these, several works have referred to the efficacy of semiochemicals from plant compounds.…”

Effect of RH-2485 on development, metamorphosis and synthesis of major proteins in female silkworm Bombyx mori

“…As ecdysone agonists, these manifest their toxic action via interaction with ecdysteroid-receptor complex of target species. RH-5992 (Tebufenozide) had undergone a considerable field evaluation and had proven to be very efficient in controlling lepidopteran pests in orchards, vineyards, vegetable field and forests and marketed under the brand name MIMIC , CONFIRM , ROMDAN (Smagghe et al 1998). RH-5992 was reported to have high potential in integrated pest management as it exhibited low toxicity to non-target species like mammals, birds, and fishes and is considered safe to beneficial arthropods, parasitoids and predators.…”

Synergism of diacylhydrazine insecticides with metyrapone and diethylmaleate

“…Although insects are capable of resisting toxic effects of insecticides through a variety of defence mechanisms, the most important route of insecticide resistance is in many cases an enhanced detoxifying metabolism. For tebufenozide, a previous study indicated that oxidation is a major route of breakdown in artificially selected larvae of S. exigua ( Smagghe et al., 1998b).…”