Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy coul...Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy could destabilize management programs for this insect. The present research evaluated the compatibility of seed treatments with two other potential management tactics--plant resistance and shallow flooding-by conducting two split-plot experiments in 2009 and 2011. In both experiments, no substantial antago- nism was found among the 3 different tactics. Statistical interactions in these experiments arose from the strong and persistent effects of chlorantraniliprole on larval densities rather than incompatibility of tactics. In 2009, weevil densities differed among varieties and were significantly lower on the cultivar ＂Jefferson.＂ In 2011, weevil densities were reduced sig- nificantly in shallow-flooded plots compared to deep-flooded plots. Significant reductions in weevil numbers by chlorantraniliprole seed treatments, even at application rates 5 fold lower than commercially recommended rates, demonstrated the potential to reduce appli- cation rates of this highly potent larvicide. These latter results suggest that future studies on the relationship between chlorantraniliprole seed treatment rate and weevil fitness are warranted.展开更多
The rice water weevil,Lissorhoptrus oryzophilus Kuschel(Coleoptera:Curculionidae),reproduces by sex in the Southeastern United States,but reproduces by parthenogenesis in California and other invaded regions in Asia a...The rice water weevil,Lissorhoptrus oryzophilus Kuschel(Coleoptera:Curculionidae),reproduces by sex in the Southeastern United States,but reproduces by parthenogenesis in California and other invaded regions in Asia and Europe.The objective of this study was to create a parthenogenetic gene expression profile of the rice water weevil in order to gain a better insight into the molecular mechanisms of parthenogenesis in the weevil.Suppression subtractive hybridization(SSH) technique was employed for profiling differential gene expression in the developed ovary between the parthenogenetic and bisexual female rice water weevils.A total of 70 contigs were obtained,and the BLASTX search identified putatively 28 genes with differential functions.According to the cytological process of parthenogenesis,the tubulin alpha-1 chain and signal transduction genes etc.were selected for real time quantitative RT-PCR analyses,and their possible functions related to the molecular mechanism of parthenogenesis were discussed.The tubulin alpha-1 chain and some signal transduction genes may be related to the molecular mechanisms of parthenogenesis of the rice water weevil.展开更多
Rice water weevil(Lissorhoptrus oryzophilus) is an important pest of paddy rice crops in Liaoning Province that was first described as a new alien invasive species in 1992.High quality DNA was successfully isolated an...Rice water weevil(Lissorhoptrus oryzophilus) is an important pest of paddy rice crops in Liaoning Province that was first described as a new alien invasive species in 1992.High quality DNA was successfully isolated and RAPD was effectively used to study genetic similarity and genetic variability of this insect among 120 individuals using eight primers.The high resolution provided by random amplified polymorphic DNA(RAPDs),in combination with efficient genetic distance estimators,allowed a preliminary description of the ecology and evolution of the populations of this insect in Liaoning Province.The results are compatible with a unique event of colonization and parthenogenesis,followed by the spreading of the water weevil across the surrounding Liaoning areas.A comparison of the results obtained with different genetic distance estimators is presented that show Suizhong group(pop3) is significant difference from the others which are generally similar.It means that: 1) Populations of rice water weevil from different area have different origin;2) Its rapid spread causes mainly by east populations in Liaoning;3) Host dis-continuum limits west population spread and design host interval can control the pest extending.However,it is still thought that the spreading tracks of this insect are not defined and need to be further studied.展开更多
文摘Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy could destabilize management programs for this insect. The present research evaluated the compatibility of seed treatments with two other potential management tactics--plant resistance and shallow flooding-by conducting two split-plot experiments in 2009 and 2011. In both experiments, no substantial antago- nism was found among the 3 different tactics. Statistical interactions in these experiments arose from the strong and persistent effects of chlorantraniliprole on larval densities rather than incompatibility of tactics. In 2009, weevil densities differed among varieties and were significantly lower on the cultivar ＂Jefferson.＂ In 2011, weevil densities were reduced sig- nificantly in shallow-flooded plots compared to deep-flooded plots. Significant reductions in weevil numbers by chlorantraniliprole seed treatments, even at application rates 5 fold lower than commercially recommended rates, demonstrated the potential to reduce appli- cation rates of this highly potent larvicide. These latter results suggest that future studies on the relationship between chlorantraniliprole seed treatment rate and weevil fitness are warranted.
基金Supported by the National Key Basic Research and Development Program of China (Grant No. 2009CB119200)National High Technology Research and Development Program of China (Grant No.2007AA10Z220)Key Projects in the National Science & Technology Pillar Program in the Eleventh Five-year Plan Period (Grant No.2006BAD17B06)
文摘The rice water weevil,Lissorhoptrus oryzophilus Kuschel(Coleoptera:Curculionidae),reproduces by sex in the Southeastern United States,but reproduces by parthenogenesis in California and other invaded regions in Asia and Europe.The objective of this study was to create a parthenogenetic gene expression profile of the rice water weevil in order to gain a better insight into the molecular mechanisms of parthenogenesis in the weevil.Suppression subtractive hybridization(SSH) technique was employed for profiling differential gene expression in the developed ovary between the parthenogenetic and bisexual female rice water weevils.A total of 70 contigs were obtained,and the BLASTX search identified putatively 28 genes with differential functions.According to the cytological process of parthenogenesis,the tubulin alpha-1 chain and signal transduction genes etc.were selected for real time quantitative RT-PCR analyses,and their possible functions related to the molecular mechanism of parthenogenesis were discussed.The tubulin alpha-1 chain and some signal transduction genes may be related to the molecular mechanisms of parthenogenesis of the rice water weevil.
文摘Rice water weevil(Lissorhoptrus oryzophilus) is an important pest of paddy rice crops in Liaoning Province that was first described as a new alien invasive species in 1992.High quality DNA was successfully isolated and RAPD was effectively used to study genetic similarity and genetic variability of this insect among 120 individuals using eight primers.The high resolution provided by random amplified polymorphic DNA(RAPDs),in combination with efficient genetic distance estimators,allowed a preliminary description of the ecology and evolution of the populations of this insect in Liaoning Province.The results are compatible with a unique event of colonization and parthenogenesis,followed by the spreading of the water weevil across the surrounding Liaoning areas.A comparison of the results obtained with different genetic distance estimators is presented that show Suizhong group(pop3) is significant difference from the others which are generally similar.It means that: 1) Populations of rice water weevil from different area have different origin;2) Its rapid spread causes mainly by east populations in Liaoning;3) Host dis-continuum limits west population spread and design host interval can control the pest extending.However,it is still thought that the spreading tracks of this insect are not defined and need to be further studied.
