The selective toxicity of six kinds of insecticides, including imidacloprid, imidacloprid+synergist (SV1), fenvalerate, endosulfan, methomyl and dimethoate, between the green peach aphid (Myzus persicae Sulzer) a...The selective toxicity of six kinds of insecticides, including imidacloprid, imidacloprid+synergist (SV1), fenvalerate, endosulfan, methomyl and dimethoate, between the green peach aphid (Myzus persicae Sulzer) and two species of ladybirds (Coccinella septempunctata Linnaeus and Propylaea japonica Thunbery), was investigated in the laboratory. The results showed that both imidacloprid WP and imidacloprid+synergist (SV1) EC possessed the highest toxicity to the aphids. Between C. septempunctata and M. persicae and between P. japonica and M. persicae, the selective toxicity ratios (STRs) of imidacloprid WP, imidacloprid+ synergist (SV1) EC and endosulfan EC were 37.6 and 13.0, 9.84 and 7.75, 54.0 and 7.28 respectively. All of them showed rather high selective toxicity. The STRs of fenvalerate EC, dimethoate EC and methomyl EC were all very low, ranging from 0.02 to 0.21, indicating their low degree of safety to the two species of ladybirds. The results demonstrated that imidacloprid WP and imidacloprid+SV1 EC not only had rather high toxicity to the aphids, but also reduced strikingly the reproduction rate and fecundity of the survival aphids. Insecticides can induce the relative fitness of insects decrease. Among the six insecticides tested with M. persicae, the following were insecticides and the order of induction was: imidacloprid + SV1> imidacloprid > endosulfan > methomyl > fenvalerate > dimethoate.展开更多
RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect pests.The 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pe...RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect pests.The 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pests attacking solanaceous plants in Asia.In this study,the potential of dietary RNAi to manage H.vigintioctopunctata was investigated using both in vitro synthesized and bacterially expressed double-stranded RNAs(dsRNAs)of HvvATPase A and HvvATPase E.The expression levels of HvvATPase A and HvvATPase E were higher in Malpighian tubules than in other tissue types.The silencing of HvvATPase A and HvvATPase E led to significant mortality in H.vigintioctopunctata larvae.In addition,the ingestion of HvvATPase A and HvvATPase E significantly deterred feeding behavior and subsequently arrested the development of H.vigintioctopunctata.Notably,the bacterially expressed dsRNAs consistently caused higher mortality in larvae and adults.Finally,the nontarget effects of the dsRNAs of H.vigintioctopunctata on the predatory ladybeetle Propylaea japonica were evaluated.P.japonica 1st instar larvae were administered vATPase A and vATPase E dsRNAs from H.vigintioctopunctata and P.japonica under the worst-case scenario,in which dsGFP served as negative control.There were significant effects of dsHvvATPase A on P.japonica at the transcriptional level but not at the organismal level,whereas dsHvvATPase E did not effect P.japonica at either the transcriptional or the organismal level.Collectively,the results of the study suggest that HvvATPase A and HvvATPase E can act as novel molecular targets for the control of H.vigintioctopunctata.展开更多
文摘The selective toxicity of six kinds of insecticides, including imidacloprid, imidacloprid+synergist (SV1), fenvalerate, endosulfan, methomyl and dimethoate, between the green peach aphid (Myzus persicae Sulzer) and two species of ladybirds (Coccinella septempunctata Linnaeus and Propylaea japonica Thunbery), was investigated in the laboratory. The results showed that both imidacloprid WP and imidacloprid+synergist (SV1) EC possessed the highest toxicity to the aphids. Between C. septempunctata and M. persicae and between P. japonica and M. persicae, the selective toxicity ratios (STRs) of imidacloprid WP, imidacloprid+ synergist (SV1) EC and endosulfan EC were 37.6 and 13.0, 9.84 and 7.75, 54.0 and 7.28 respectively. All of them showed rather high selective toxicity. The STRs of fenvalerate EC, dimethoate EC and methomyl EC were all very low, ranging from 0.02 to 0.21, indicating their low degree of safety to the two species of ladybirds. The results demonstrated that imidacloprid WP and imidacloprid+SV1 EC not only had rather high toxicity to the aphids, but also reduced strikingly the reproduction rate and fecundity of the survival aphids. Insecticides can induce the relative fitness of insects decrease. Among the six insecticides tested with M. persicae, the following were insecticides and the order of induction was: imidacloprid + SV1> imidacloprid > endosulfan > methomyl > fenvalerate > dimethoate.
基金supported by the National Key R&D Program of China(2017YFD0200900)National Natural Science Foundation of China(31972269)GDUPS(2017).
文摘RNA interference(RNAi)has emerged as a powerful tool for developing novel management strategies for controlling insect pests.The 28-spotted ladybeetle,Henosepilachna vigintioctopunctata is one of the most important pests attacking solanaceous plants in Asia.In this study,the potential of dietary RNAi to manage H.vigintioctopunctata was investigated using both in vitro synthesized and bacterially expressed double-stranded RNAs(dsRNAs)of HvvATPase A and HvvATPase E.The expression levels of HvvATPase A and HvvATPase E were higher in Malpighian tubules than in other tissue types.The silencing of HvvATPase A and HvvATPase E led to significant mortality in H.vigintioctopunctata larvae.In addition,the ingestion of HvvATPase A and HvvATPase E significantly deterred feeding behavior and subsequently arrested the development of H.vigintioctopunctata.Notably,the bacterially expressed dsRNAs consistently caused higher mortality in larvae and adults.Finally,the nontarget effects of the dsRNAs of H.vigintioctopunctata on the predatory ladybeetle Propylaea japonica were evaluated.P.japonica 1st instar larvae were administered vATPase A and vATPase E dsRNAs from H.vigintioctopunctata and P.japonica under the worst-case scenario,in which dsGFP served as negative control.There were significant effects of dsHvvATPase A on P.japonica at the transcriptional level but not at the organismal level,whereas dsHvvATPase E did not effect P.japonica at either the transcriptional or the organismal level.Collectively,the results of the study suggest that HvvATPase A and HvvATPase E can act as novel molecular targets for the control of H.vigintioctopunctata.
