Integrated pest management （IPM） is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as cur...Integrated pest management （IPM） is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as curb economic loss with less dependency on chemical pesticides. One practice in IPM is the use of biological control agents such as predatory insects. In this study, we assessed the response of predatory natural enemies to pest outbreak and water stress, and document the habitat associations of potential pest predators. The abundances of 2 predatory insect species, namely Sycanus dichotomus and Cosmolestes pictieeps （Hemiptera： Reduviidae）, were compared bagworm outbreak sites and nonoutbreak sites within oil palm plantations. We also examined habitat characteristics that influence the abundances of both predatory species. We found that the abundance of C. picticeps was significantly higher in bagworm outbreak sites than in nonoutbreak sites. There were no significant differences in the abundance ofS. dichotomus among outbreak and non-outbreak sites. Both species responded negatively to water stress in oil palm plantations. Concerning the relationship between predatory insect abundance and in situ habitat quality characteristics, our models explained 46.36% of variation for C. picticeps and 23.17% of variation for S. dichotomus. Both species of predatory insects thrived from the planting of multiple beneficial plants in oil palm plantations. The results suggest that C. picticeps can be used as a biological agent to control bagworm populations in oil palm plantations, but S. dichotomus has no or little potential for such ecosystem service.展开更多
Despite extensive studies on the morphology of holometabolous insects and their larvae,the morphological transformations of internal structures during metamorphosis have been rarely documented.Here,we used micro-compu...Despite extensive studies on the morphology of holometabolous insects and their larvae,the morphological transformations of internal structures during metamorphosis have been rarely documented.Here,we used micro-computed tomography to investigate the developmental transformations of thoracic structures in the green lacewing Chrysopa pallens(Rambur,1838)(Neuroptera:Chrysopidae),with emphasis on the development of the digestive,tracheal,and thoracic skeleto-muscular system.All the adult organs were modified during the prepupal or early pupal stage.The histolysis and remodeling began with the skeletal elements,followed by changes in the digestive system before it concluded with modifications of the musculature.Similar to the tracheal system’s development,the digestive system did not disappear completely throughout metamorphosis but underwent a dramatic morphological change,which included the midgut significantly decreasing in size during the pupal stage.Our results provide important evidence for understanding the evolutionary pattern of developmental transformations in different major lineages of Holometabola.展开更多
文摘Integrated pest management （IPM） is widely practiced in commercial oil palm agriculture. This management system is intended to minimize the number of attacks by pest insects such as bagworms on crops, as well as curb economic loss with less dependency on chemical pesticides. One practice in IPM is the use of biological control agents such as predatory insects. In this study, we assessed the response of predatory natural enemies to pest outbreak and water stress, and document the habitat associations of potential pest predators. The abundances of 2 predatory insect species, namely Sycanus dichotomus and Cosmolestes pictieeps （Hemiptera： Reduviidae）, were compared bagworm outbreak sites and nonoutbreak sites within oil palm plantations. We also examined habitat characteristics that influence the abundances of both predatory species. We found that the abundance of C. picticeps was significantly higher in bagworm outbreak sites than in nonoutbreak sites. There were no significant differences in the abundance ofS. dichotomus among outbreak and non-outbreak sites. Both species responded negatively to water stress in oil palm plantations. Concerning the relationship between predatory insect abundance and in situ habitat quality characteristics, our models explained 46.36% of variation for C. picticeps and 23.17% of variation for S. dichotomus. Both species of predatory insects thrived from the planting of multiple beneficial plants in oil palm plantations. The results suggest that C. picticeps can be used as a biological agent to control bagworm populations in oil palm plantations, but S. dichotomus has no or little potential for such ecosystem service.
基金This study was supported by the National Natural Science Foundation of China(32100359,32130012)the Technological Innovation Programs of Higher Education Institutions in Shanxi(2021L430)the China Scholarship Council,which enabled CJZ to spend 12 months as a joint student at the National University of Singapore,hosted by RM.
文摘Despite extensive studies on the morphology of holometabolous insects and their larvae,the morphological transformations of internal structures during metamorphosis have been rarely documented.Here,we used micro-computed tomography to investigate the developmental transformations of thoracic structures in the green lacewing Chrysopa pallens(Rambur,1838)(Neuroptera:Chrysopidae),with emphasis on the development of the digestive,tracheal,and thoracic skeleto-muscular system.All the adult organs were modified during the prepupal or early pupal stage.The histolysis and remodeling began with the skeletal elements,followed by changes in the digestive system before it concluded with modifications of the musculature.Similar to the tracheal system’s development,the digestive system did not disappear completely throughout metamorphosis but underwent a dramatic morphological change,which included the midgut significantly decreasing in size during the pupal stage.Our results provide important evidence for understanding the evolutionary pattern of developmental transformations in different major lineages of Holometabola.
