The red imported fire ant,Solenopsis invicta Buren,poses a significant threat to biodiversity,agriculture,and public health in its introduced ranges.While chemicals such as toxic baits and dust are the main methods fo...The red imported fire ant,Solenopsis invicta Buren,poses a significant threat to biodiversity,agriculture,and public health in its introduced ranges.While chemicals such as toxic baits and dust are the main methods for S.invicta control,toxic baits are slow,requiring approximately one or two weeks,but dust can eliminate the colony of fire ants rapidly in just three to five days.To explore more active ingredients for fire ant control using dusts,the toxicity of bifenthrin and dimefluthrin,the horizontal transfer of bifenthrin and dimefluthrin dust and their efficacy in the field were tested.The results showed that the LD50(lethal dose) values of bifenthrin and dimefluthrin were 3.40 and 1.57 ng/ant,respectively.The KT50(median knockdown time) and KT95(95%knockdown time) values of a 20μg mL^(–1)bifenthrin dose were 7.179and 16.611 min,respectively.The KT50and KT95of a 5μg mL^(–1)dimefluthrin dose were 1.538 and 2.825 min,respectively.The horizontal transfers of bifenthrin and dimefluthrin among workers were effective.The mortality of recipients (secondary mortality) and secondary recipients (tertiary mortality) were both over 80%at 48 h after 0.25,0.50 and 1.00%bifenthrin dust treatments.The secondary mortality of recipients was over 99%at 48 h after 0.25,0.50 and 1.00% dimefluthrin dust treatments,but the tertiary mortality was below 20%.The field trial results showed that both bifenthrin and dimefluthrin exhibited excellent fire ant control effects,and the comprehensive control effects of 1.00%bifenthrin and dimefluthrin dusts at 14 d post-treatment were 95.87 and 85.70%,respectively.展开更多
The sting of red imported fire ant （RIFA） could cause serious allergic response in fraction of people. These allergic reactions are mainly caused by its venom, especially venom allergen Sol i 1-4. To produce large a...The sting of red imported fire ant （RIFA） could cause serious allergic response in fraction of people. These allergic reactions are mainly caused by its venom, especially venom allergen Sol i 1-4. To produce large amount of RIFA venom allergen Sol i 4 for diagnosis of RIFA allergy and allergen-specific immunotherapy, the gene encoding this protein was amplified and cloned into the prokaryotic expression vector pET43, la. The recombinant plasmid was used to transform competent cells and the recombinant proteins were expressed in E. coll. SDS-PAGE and Western blotting analysis indicated that high-level expression of Sol i 4 protein was successfully achieved. Allergenic activity analysis of the recombinant allergen Sol i 4 was then performed on rabbit. The result showed that the recombinant protein obtained had significant allergenic activity. It indicated that the recombinant allergen Sol i 4 of RIFA venom was successfully expressed in E. coli, which provided foundation for further developing therapeutic and diagnosis reagents of RIFA allergy.展开更多
Juvenile hormone(JH)acts in the regulation of caste differentiation between queens and workers(i.e.,with or without reproductive capacity)during vitellin synthesis and oogenesis in social insects.However,the regulator...Juvenile hormone(JH)acts in the regulation of caste differentiation between queens and workers(i.e.,with or without reproductive capacity)during vitellin synthesis and oogenesis in social insects.However,the regulatory mechanisms have not yet been elucidated.Here,we identified a highly expressed microRNA(miRNA),miR-1175-3p,in the red imported fire ant,Solenopsis invicta.We found that miR-1175-3p is prominently present in the fat bodies and ovaries of workers.Furthermore,miR-1175-3p interacts with its target gene,broad-complex core(Br-C),in the fat bodies.By utilizing miR-1175-3p agomir,we successfully suppressed the expression of the Br-C protein in queens,resulting in reduced vitellogenin expression,fewer eggs,and poorly developed ovaries.Conversely,decreasing miR-1175-3p levels led to the increased expression of Br-C and vitellogenin in workers,triggering the“re-development”of the ovaries.Moreover,when queens were fed with JH,the expression of miR-1175-3p decreased,whereas the expression of vitellogenin-2 and vitellogenin-3 increased.Notably,the suppression of fertility in queens caused by treatment with agomir miR-1175-3p was completely rescued by the increased vitellogenin expression induced by being fed with JH.These results suggest the critical role of miR-1175-3p in JH-regulated reproduction,shedding light on the molecular mechanism underlying miRNA-mediated fecundity in social insects and providing a novel strategy for managing S.invicta.展开更多
The red imported fire ant（RIFA, Solenopsis invicta）, a notorious invasive insect, has received considerable attention owing to its impacts on native biodiversity, agriculture, and human health. Under global warming,...The red imported fire ant（RIFA, Solenopsis invicta）, a notorious invasive insect, has received considerable attention owing to its impacts on native biodiversity, agriculture, and human health. Under global warming, the inhabitable area of the RIFA may be enlarged. However, few studies have focused on the potential range expansion of the RIFA in East Asia. Using a process-based physiological model, we simulated the potential range of the RIFA in China based on gridded temperature datasets for the current（2004–2012） and future（2090–2100） climates under Representative Concentration Pathway（RCP） 4.5 and RCP 8.5. It was found that the southeastern part of China（below 32°N） is suitable for RIFA proliferation. The present distribution area of the RIFA corresponds well with the potential range simulated by the model. In the RCP 4.5 and RCP 8.5 warming scenarios, the inhabitable area of the RIFA along the northern boundary would on average extend 101.3±85.7（mean±SD） and 701.2±156.9 km, respectively, by the end of the 21 st century. Therefore, future climate change would significantly affect the inhabitable area of the RIFA. Our results provide the basis for local quarantine officials to curtail accidental introductions of this insect, especially in the certain and possible infestation zones.展开更多
基金supported by the Special Project for Sustainable Development Science and Technology of Shenzhen, China (2021N007)the Special Project for Red Imported Fire Ant Management, Shenzhen Agricultural Science and Technology Promotion Center, China (20220900044zbzjbc)。
文摘The red imported fire ant,Solenopsis invicta Buren,poses a significant threat to biodiversity,agriculture,and public health in its introduced ranges.While chemicals such as toxic baits and dust are the main methods for S.invicta control,toxic baits are slow,requiring approximately one or two weeks,but dust can eliminate the colony of fire ants rapidly in just three to five days.To explore more active ingredients for fire ant control using dusts,the toxicity of bifenthrin and dimefluthrin,the horizontal transfer of bifenthrin and dimefluthrin dust and their efficacy in the field were tested.The results showed that the LD50(lethal dose) values of bifenthrin and dimefluthrin were 3.40 and 1.57 ng/ant,respectively.The KT50(median knockdown time) and KT95(95%knockdown time) values of a 20μg mL^(–1)bifenthrin dose were 7.179and 16.611 min,respectively.The KT50and KT95of a 5μg mL^(–1)dimefluthrin dose were 1.538 and 2.825 min,respectively.The horizontal transfers of bifenthrin and dimefluthrin among workers were effective.The mortality of recipients (secondary mortality) and secondary recipients (tertiary mortality) were both over 80%at 48 h after 0.25,0.50 and 1.00%bifenthrin dust treatments.The secondary mortality of recipients was over 99%at 48 h after 0.25,0.50 and 1.00% dimefluthrin dust treatments,but the tertiary mortality was below 20%.The field trial results showed that both bifenthrin and dimefluthrin exhibited excellent fire ant control effects,and the comprehensive control effects of 1.00%bifenthrin and dimefluthrin dusts at 14 d post-treatment were 95.87 and 85.70%,respectively.
基金supported by the Key Pro-gram Foundation of General Administration of QualitySupervision, Inspection and Quarantine of China(2005IK169).
文摘The sting of red imported fire ant （RIFA） could cause serious allergic response in fraction of people. These allergic reactions are mainly caused by its venom, especially venom allergen Sol i 1-4. To produce large amount of RIFA venom allergen Sol i 4 for diagnosis of RIFA allergy and allergen-specific immunotherapy, the gene encoding this protein was amplified and cloned into the prokaryotic expression vector pET43, la. The recombinant plasmid was used to transform competent cells and the recombinant proteins were expressed in E. coll. SDS-PAGE and Western blotting analysis indicated that high-level expression of Sol i 4 protein was successfully achieved. Allergenic activity analysis of the recombinant allergen Sol i 4 was then performed on rabbit. The result showed that the recombinant protein obtained had significant allergenic activity. It indicated that the recombinant allergen Sol i 4 of RIFA venom was successfully expressed in E. coli, which provided foundation for further developing therapeutic and diagnosis reagents of RIFA allergy.
基金National Key R&D Program of China(2021YFD1000500)the Natural Science Foundation of Guangdong Province(2023A1515012108)the Foundation of Guangdong Academy of Agricultural Sciences(R2023PY-JX010).
文摘Juvenile hormone(JH)acts in the regulation of caste differentiation between queens and workers(i.e.,with or without reproductive capacity)during vitellin synthesis and oogenesis in social insects.However,the regulatory mechanisms have not yet been elucidated.Here,we identified a highly expressed microRNA(miRNA),miR-1175-3p,in the red imported fire ant,Solenopsis invicta.We found that miR-1175-3p is prominently present in the fat bodies and ovaries of workers.Furthermore,miR-1175-3p interacts with its target gene,broad-complex core(Br-C),in the fat bodies.By utilizing miR-1175-3p agomir,we successfully suppressed the expression of the Br-C protein in queens,resulting in reduced vitellogenin expression,fewer eggs,and poorly developed ovaries.Conversely,decreasing miR-1175-3p levels led to the increased expression of Br-C and vitellogenin in workers,triggering the“re-development”of the ovaries.Moreover,when queens were fed with JH,the expression of miR-1175-3p decreased,whereas the expression of vitellogenin-2 and vitellogenin-3 increased.Notably,the suppression of fertility in queens caused by treatment with agomir miR-1175-3p was completely rescued by the increased vitellogenin expression induced by being fed with JH.These results suggest the critical role of miR-1175-3p in JH-regulated reproduction,shedding light on the molecular mechanism underlying miRNA-mediated fecundity in social insects and providing a novel strategy for managing S.invicta.
基金National Key Research and Development Program of China,No.2016YFC1201302
文摘The red imported fire ant（RIFA, Solenopsis invicta）, a notorious invasive insect, has received considerable attention owing to its impacts on native biodiversity, agriculture, and human health. Under global warming, the inhabitable area of the RIFA may be enlarged. However, few studies have focused on the potential range expansion of the RIFA in East Asia. Using a process-based physiological model, we simulated the potential range of the RIFA in China based on gridded temperature datasets for the current（2004–2012） and future（2090–2100） climates under Representative Concentration Pathway（RCP） 4.5 and RCP 8.5. It was found that the southeastern part of China（below 32°N） is suitable for RIFA proliferation. The present distribution area of the RIFA corresponds well with the potential range simulated by the model. In the RCP 4.5 and RCP 8.5 warming scenarios, the inhabitable area of the RIFA along the northern boundary would on average extend 101.3±85.7（mean±SD） and 701.2±156.9 km, respectively, by the end of the 21 st century. Therefore, future climate change would significantly affect the inhabitable area of the RIFA. Our results provide the basis for local quarantine officials to curtail accidental introductions of this insect, especially in the certain and possible infestation zones.
