Bioactivities of two tebufenozide derivatives against five lepidopteran pests

In order to compare the toxicities of tebufenozide and its derivatives,the toxicities of tebufenozide derivatives 0593(Ⅲf)and 0673 against five lepidopteran pests,i.e.,Spodoptera exigua(Hubner),Prodenia litura(Fabricius),Plutella xylostella(Linnaeus),Helicoverpa armigera(Hubner)and Ostrinia furnacalis(Guene),were investigated with leaf-dip,dipping and topical application compared with the tebufenozide.The effects of tebufenozide and 0593 on growth and development of S.exigua were studied with leaf-dip.The results showed that the contact toxicities of 0593 and 0673 to 4th-instar larvae of S.exigua were 11.3 and 7.4 times that of tebufenozide,respectively.The contact toxicities of 0593 and 0673 to 4th-instar larvae of P.litura were 30.4 and 24.7 times that of tebufenozide,respectively.The toxicities of 0593 and 0673 to 3rd-instar larvae of P.xylostella with dipping method were 4.7 and 4.5 times that of tebufenozide,respectively,and the contact toxicities of 0593 and 0673 to 3rd-instar larvae of H.armigera were 15.5 and 15.2 times that of tebufenozide,respectively.The contact toxicities of 0593 and 0673 to 4th-instar larvae of O.furnacalis were 1.3 and 2.0 times that of tebufenozide,respectively.The toxicities of 0593 and 0673 to the five pests were higher than that of tebufenozide,but the differences of toxicities between 0593 and 0673 were not significant.Treated with tebufenozide and 0593,the 2nd-instar larvae of S.exigua died unceasingly after 72 h;the pupation rate and the number of normal pupae were decreased;in addition,adult emergence ratio,eggs laid per female and egg hatchability were also reduced significantly,and the fecundity was so affected significantly.Tebufenozide derivative 0593 showed more disadvantageous influence than tebufenozide on the fecundity of S.exigua at the same concentration.The results suggest that tebufenozide derivative 0593 is a pesticide with higher bioactivity against lepidopteran larvae and stronger harmful effects on their development and fecundity than tebufenozide,so it is worthy to exploit.