The prevalence of Solenopsis invicta is associated with habitat diversity,with a preference for various habitats ranked in the following order:ponds,wastelands,green belts,roads,parks,farmlands,and villages.Consequent...The prevalence of Solenopsis invicta is associated with habitat diversity,with a preference for various habitats ranked in the following order:ponds,wastelands,green belts,roads,parks,farmlands,and villages.Consequently,management strategies should be tailored to each habitat.There are two occurrence peaks of S.invicta throughout the year,specifically from March to April and from September to October.It is essential to emphasize prevention and control measures during the active periods of S.invicta.To enhance the effectiveness of these measures,supplementary control should be implemented within 10-15 d following the initial prevention and control efforts.Furthermore,the efficacy of prevention and control is notably higher on the second to third day immediately following rainfall.This study aimed to evaluate the efficacy of various agents in controlling S.invicta.A comparative analysis was conducted on the efficacy of three different brands of agents against S.invicta.The findings indicated that a concentration of 0.08%-0.10%indoxacarb exhibited a comparable extermination effect on S.invicta worker ants.However,agents with larger particle sizes demonstrated a reduced efficacy in exterminating S.invicta nests.展开更多
Based on the biological characteristics of Solenopsis invicta and the structural characteristics of its ant nest,a fast and efficient closed treatment device was developed.Compared with the simple chemical treatment c...Based on the biological characteristics of Solenopsis invicta and the structural characteristics of its ant nest,a fast and efficient closed treatment device was developed.Compared with the simple chemical treatment commonly used at present,the developed treatment device(the ant nest control cover)is a fast and efficient method to exterminate S.invicta in 7 d,featured by short course,quick results and good effect.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
The red imported fire ant (Solenopsis invicta) is a global major invasive pest, and has caused significant economic, social and environmental impacts since its invasion to mainland of China in 2004. To date, chemica...The red imported fire ant (Solenopsis invicta) is a global major invasive pest, and has caused significant economic, social and environmental impacts since its invasion to mainland of China in 2004. To date, chemical control has been the most effective measure. However, the long-term use of chemicals would lead to an unexpected rebound. To understand the risks and explore the mechanisms of detoxification or induction to insecticides in S. invicta, the O-demethylase activity and expression of cytochrome P450 genes of workers and queens, and the effects of chlorpyrifos and fipronil exposure in workers were investigated. Biochemical assays showed the O-demethylase activity of cytochrome P450 was significantly higher in workers than in queens (1.66-fold), and was significantly induced in workers exposed to chlorpyrifos and fipronil, reaching a maximum (3.00- and 1.95-fold) at 48 h and then decreasing dramatically compared to controls (exposed to acetone counter- part). The relative expression levels of 12 cytochrome P450 expressed sequence tags (ESTs) in workers were significantly higher than in queens (from 2.3- to 36.4-fold). Multiple cytochrome P450 genes (except 9E4) were co-up-regulated (from 1.5- to 2.86-fold) in workers exposed to fipronil. These results indicated that the increased O-demethylase activity may result from the increased transcription levels of cytochrome P450 related to detoxification of insecticides in S. invicta. It appears that cytochrome P450 plays an important role in enhanced metabolic detoxification of insecticides. At the same time, it also provides the theoretical basis for resistance management and rational usage of insecticides to control S. invicta.展开更多
Venom plays several important roles in the life of the fire ant,Solenopsis invicta Buren.Laboratory rearing significantly affected the toxin component of S.invicta.However,the molecular mechanism of the change of veno...Venom plays several important roles in the life of the fire ant,Solenopsis invicta Buren.Laboratory rearing significantly affected the toxin component of S.invicta.However,the molecular mechanism of the change of venomous components when kept in the laboratory is unclear.In this study,RNA sequencing technique(RNA-Seq)was performed to explore differentially expressed genes in the venom gland of S.invicta at 0,10,and 60 days after laboratory rearing.The RNA-Seq results showed that the expression of a large number of genes changed.The DEGs were involved in multiple pathways,including proteolysis,serine-type endopeptidase,and allergen.Furthermore,RNA-Seq and qRT-PCR data revealed that the expression of some genes related to proteolysis and allergen significantly decreased.Thus,our data generated new data relating to toxin-component and the transcriptome dynamics in the venom gland of S.invicta during laboratory rearing.展开更多
The field control effects of different concentrations of indoxacarb baits,fipronil baits and chlorfenapyr baits on Solenopsis invicta was evaluated. The results showed that at 21 post administration,the control effect...The field control effects of different concentrations of indoxacarb baits,fipronil baits and chlorfenapyr baits on Solenopsis invicta was evaluated. The results showed that at 21 post administration,the control effects of 0. 04% indoxacarb on nests and worker ants reached 100%; the control effect of 0. 02% and0. 06% indoxacarb on active nests and worker ants were 87. 50% and 100%,respectively; 0. 000 25% and 0. 000 5% fipronil and 0. 05% chlorfenapyr also had significant control effects on active nests and worker ants. At 30 d post administration,the decline rates of ant colony grade treated by 0. 04% and 0. 06% indoxacarb,0. 000 25% fipronil and 0. 05% chlorfenapyr were 100%,100%,91. 44% and 98. 11%,respectively,and the comprehensive control effect reached 97. 18%.展开更多
The green peach aphid, Myzuspersicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, th...The green peach aphid, Myzuspersicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, the aphid is now resistant to many of these and much interest has recently developed in identification of novel alternative insecticides. Venom isolated from the red imported fire ant, Solenopsisinvicta Buren, is composed of two groups of alkaloids, piperidines and piperideines, and has shown activity against many organisms including fungi, bacteria, mites and several insects. Prior to the study reported herein, no information on the venom’s activity to Myzuspersicae has been reported. Both of the alkaloids were active against M.persicae. The 24 h LC50 values were116.6 and 91.5 ppm for the piperideine and piperidine extracts, respectively. Based on overlap of the 95% fiducial limits the LC50 values for the two alkaloids did not significantly differ. At the high dosages, mortality occurred in as few as four hours and all treated aphids were dead by six hours. Little additional mortality was detected in the 48-hobservation. Both piperideine and piperidine extracts isolated from red imported fire ant venom possess sufficient activity to cause death of green peach aphids and at high dosages, death occurs rapidly. In the search for new replacements to synthetic insecticides, these extracts may offer a novel but potentially successful alternative.展开更多
Natural enemy insects are important factors in regulating plant invasion. The interactions between multiple insect species resulting from invasive plants remain poorly understood despite their potential. We observed n...Natural enemy insects are important factors in regulating plant invasion. The interactions between multiple insect species resulting from invasive plants remain poorly understood despite their potential. We observed notorious invasive plants Eupatorium adenophorum Sprengel were competedly fed by Solenopsis invicta Buren (Hymenoptera: Formicidae) and Dorylus orientalis Westwood (Hymenoptera: Formicidae) beside the scientific research base of Kunming University. It was first observed that D. orientalis was eating the epidermis, cortex, phloem and other root and stem tissues of E. adenophorum in soil. Two months later, it was observed that S. invicta ate the epidermis, cortex, phloem and other aboveground stem tissues of E. adenophorum. S. invicta attacked D. orientalis and displaced their living space by causing the later dead, injured, or even disabled. This phenomenon suggested that local herbivorous insects have adapted to E. adenophorum well, which will intensify the naturalization process of E. adenophorum in local habitats. In a homogeneous garden planting experiment of E. adenophorum conducted at the experimental base of Kunming University, the biomass of the introduced (China) populations of E. adenophorum was lower than that of the native (Mexico) populations, although there was no statistically significant difference. These results indicate a possible positive correlation between the increase in natural enemy pressure and the decrease in fitness of E. adenophorum.展开更多
The insect gustatory system participates in identifying potential food sources and avoiding toxic compounds.During this process,gustatory receptors(GRs)recognize feeding stimulant and deterrent compounds.However,the G...The insect gustatory system participates in identifying potential food sources and avoiding toxic compounds.During this process,gustatory receptors(GRs)recognize feeding stimulant and deterrent compounds.However,the GRs involved in recognizing stimulant and deterrent compounds in the red imported fire ant,Solenopsis invicta,remain unknown.Therefore,we conducted a study on the genes SinvGR1,SinvGR32b,and SinvGR28a to investigate the roles of GRs in detecting feeding stimulant and deterrent compounds.In this current study,we found that sucrose and fructose are feeding stimulants and the bitter compound quinine is a feeding deterrent.The fire ant workers showed significant behavior changes to avoid the bitter taste in feeding stimulant compounds.Reverse transcription quantitative real-time polymerase chain reaction results from developmental stages showed that the SinvGR1,SinvGR32b,and SinvGR28a genes were highly expressed in fire ant workers.Tissue-specific expression profiles indicated that SinvGR1,SinvGR32b,and SinvGR28a were specifically expressed in the antennae and foreleg tarsi of workers,whereas SinvGR32b gene transcripts were also highly accumulated in the male antennae.Furthermore,the silencing of SinvGRI or SinvGR32b alone and the co-silencing of both genes disrupted worker stimulation and feeding on sucrose and fructose.The results also showed that SinvGR28a is required for avoiding quinine,as workers with knockdown of the SinvGR28a gene failed to avoid and fed on quinine.This study first identified stimulant and deterrent compounds of fire ant workers and then the GRs involved in the taste recognition of these compounds.This study could provide potential target gustatory genes for the control of the fire ant.展开更多
DNA methylation is accomplished in animals by 2 classes of enzymes known as DNA methyltransferases, DNMT3 and DNMT 1, which perform de novo methylation and maintenance methylation, respectively. Several studies of hym...DNA methylation is accomplished in animals by 2 classes of enzymes known as DNA methyltransferases, DNMT3 and DNMT 1, which perform de novo methylation and maintenance methylation, respectively. Several studies of hymenopteran eusocial insects suggest that DNA methylation is capable of influencing developmental plasticity. However, fundamental questions remain about the patterning of DNA methylation during the course of insect development. In this study, we performed quantitative real-time PCR (qPCR) on transcripts from the single-copy orthologs of DNMT1 and DNMT3 in the red imported fire ant, Solenopsis invicta. In particular, we assessed the expression of S. invicta Dnmtl and Dnmt3 mRNA during 7 stages of worker development, among behaviorally distinct adults, and among male and female gonads. Dnmt3 was most highly expressed during embryonic development, whereas Dnmtl was similarly expressed throughout the course of develop- ment. Moreover, Dnmtl and Dnmt3 were highly expressed in testes and ovaries. Neither Dnmt was significantly differentially expressed among heads of behaviorally distinct adult castes. Our results support the hypothesis that extensive patterning of DNA methylation occurs during gametogenesis and embryogenesis in the insect order Hymenoptera.展开更多
One of the most invasive species worldwide, Solenopsis invicta Buren, has been described in China since 2003. Recent studies have suggested that China populations are the result of introductions from the USA; however,...One of the most invasive species worldwide, Solenopsis invicta Buren, has been described in China since 2003. Recent studies have suggested that China populations are the result of introductions from the USA; however, detailed molecular studies need to be performed in order to understand the expansion and potential multiple introductions from other countries into China. As there were populations of red imported fire ant, S. invicta in different areas and with different methods of introduction, mitochondrial cytochrome oxidase Ⅰ gene was used as a marker from 12 populations in four cities in Fujian Province, China, to determine the relationship of invasion among these populations. The three most common haplotypes previously describe in invasive populations of S. invicta: H5, H22 and H36, were found in Fujian. However, frequencies in each city were different. For instance, three populations from Longyan city which invaded with waste plastics, shared haplotype H5. Populations from Xiamen city and Jinjiang city which dispersed with nursery stock, sward and scrap leather, shared haplotype H22. The population from Nanyan village of Xinluo district, Longyan city, bore haplotype H36. Mitochondrial data reveals that the invasion history of S. invicta in Fujian Province is complex, including multiple invasions probably from other provinces within China. Security measures to prevent S. invicta spreading within China are as important as from overseas.展开更多
基金Supported by 2024 Red Imported Fire Ant Prevention and Control Project of Huizhou City.
文摘The prevalence of Solenopsis invicta is associated with habitat diversity,with a preference for various habitats ranked in the following order:ponds,wastelands,green belts,roads,parks,farmlands,and villages.Consequently,management strategies should be tailored to each habitat.There are two occurrence peaks of S.invicta throughout the year,specifically from March to April and from September to October.It is essential to emphasize prevention and control measures during the active periods of S.invicta.To enhance the effectiveness of these measures,supplementary control should be implemented within 10-15 d following the initial prevention and control efforts.Furthermore,the efficacy of prevention and control is notably higher on the second to third day immediately following rainfall.This study aimed to evaluate the efficacy of various agents in controlling S.invicta.A comparative analysis was conducted on the efficacy of three different brands of agents against S.invicta.The findings indicated that a concentration of 0.08%-0.10%indoxacarb exhibited a comparable extermination effect on S.invicta worker ants.However,agents with larger particle sizes demonstrated a reduced efficacy in exterminating S.invicta nests.
基金Science and Technology Research Program of Xiamen Customs(2020XK08).
文摘Based on the biological characteristics of Solenopsis invicta and the structural characteristics of its ant nest,a fast and efficient closed treatment device was developed.Compared with the simple chemical treatment commonly used at present,the developed treatment device(the ant nest control cover)is a fast and efficient method to exterminate S.invicta in 7 d,featured by short course,quick results and good effect.
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.
基金the National Natural Science Foundation of China (31071712) for the financial support given to the present research work
文摘The red imported fire ant (Solenopsis invicta) is a global major invasive pest, and has caused significant economic, social and environmental impacts since its invasion to mainland of China in 2004. To date, chemical control has been the most effective measure. However, the long-term use of chemicals would lead to an unexpected rebound. To understand the risks and explore the mechanisms of detoxification or induction to insecticides in S. invicta, the O-demethylase activity and expression of cytochrome P450 genes of workers and queens, and the effects of chlorpyrifos and fipronil exposure in workers were investigated. Biochemical assays showed the O-demethylase activity of cytochrome P450 was significantly higher in workers than in queens (1.66-fold), and was significantly induced in workers exposed to chlorpyrifos and fipronil, reaching a maximum (3.00- and 1.95-fold) at 48 h and then decreasing dramatically compared to controls (exposed to acetone counter- part). The relative expression levels of 12 cytochrome P450 expressed sequence tags (ESTs) in workers were significantly higher than in queens (from 2.3- to 36.4-fold). Multiple cytochrome P450 genes (except 9E4) were co-up-regulated (from 1.5- to 2.86-fold) in workers exposed to fipronil. These results indicated that the increased O-demethylase activity may result from the increased transcription levels of cytochrome P450 related to detoxification of insecticides in S. invicta. It appears that cytochrome P450 plays an important role in enhanced metabolic detoxification of insecticides. At the same time, it also provides the theoretical basis for resistance management and rational usage of insecticides to control S. invicta.
基金This study was approved by the Institutional Review Board(IRB)Institutional of Plant Protection and Microbiology,Zhejiang Academy of Agricultural Sciences.The approval code is 2020AWE061801The approval date is June 19,2020.
文摘Venom plays several important roles in the life of the fire ant,Solenopsis invicta Buren.Laboratory rearing significantly affected the toxin component of S.invicta.However,the molecular mechanism of the change of venomous components when kept in the laboratory is unclear.In this study,RNA sequencing technique(RNA-Seq)was performed to explore differentially expressed genes in the venom gland of S.invicta at 0,10,and 60 days after laboratory rearing.The RNA-Seq results showed that the expression of a large number of genes changed.The DEGs were involved in multiple pathways,including proteolysis,serine-type endopeptidase,and allergen.Furthermore,RNA-Seq and qRT-PCR data revealed that the expression of some genes related to proteolysis and allergen significantly decreased.Thus,our data generated new data relating to toxin-component and the transcriptome dynamics in the venom gland of S.invicta during laboratory rearing.
基金Supported by Project of Liuzhou Science and Technology Bureau"Investigation and Prevention Countermeasures of Fire Ants in Liuzhou City"(2013J020101)
文摘The field control effects of different concentrations of indoxacarb baits,fipronil baits and chlorfenapyr baits on Solenopsis invicta was evaluated. The results showed that at 21 post administration,the control effects of 0. 04% indoxacarb on nests and worker ants reached 100%; the control effect of 0. 02% and0. 06% indoxacarb on active nests and worker ants were 87. 50% and 100%,respectively; 0. 000 25% and 0. 000 5% fipronil and 0. 05% chlorfenapyr also had significant control effects on active nests and worker ants. At 30 d post administration,the decline rates of ant colony grade treated by 0. 04% and 0. 06% indoxacarb,0. 000 25% fipronil and 0. 05% chlorfenapyr were 100%,100%,91. 44% and 98. 11%,respectively,and the comprehensive control effect reached 97. 18%.
文摘The green peach aphid, Myzuspersicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, the aphid is now resistant to many of these and much interest has recently developed in identification of novel alternative insecticides. Venom isolated from the red imported fire ant, Solenopsisinvicta Buren, is composed of two groups of alkaloids, piperidines and piperideines, and has shown activity against many organisms including fungi, bacteria, mites and several insects. Prior to the study reported herein, no information on the venom’s activity to Myzuspersicae has been reported. Both of the alkaloids were active against M.persicae. The 24 h LC50 values were116.6 and 91.5 ppm for the piperideine and piperidine extracts, respectively. Based on overlap of the 95% fiducial limits the LC50 values for the two alkaloids did not significantly differ. At the high dosages, mortality occurred in as few as four hours and all treated aphids were dead by six hours. Little additional mortality was detected in the 48-hobservation. Both piperideine and piperidine extracts isolated from red imported fire ant venom possess sufficient activity to cause death of green peach aphids and at high dosages, death occurs rapidly. In the search for new replacements to synthetic insecticides, these extracts may offer a novel but potentially successful alternative.
文摘Natural enemy insects are important factors in regulating plant invasion. The interactions between multiple insect species resulting from invasive plants remain poorly understood despite their potential. We observed notorious invasive plants Eupatorium adenophorum Sprengel were competedly fed by Solenopsis invicta Buren (Hymenoptera: Formicidae) and Dorylus orientalis Westwood (Hymenoptera: Formicidae) beside the scientific research base of Kunming University. It was first observed that D. orientalis was eating the epidermis, cortex, phloem and other root and stem tissues of E. adenophorum in soil. Two months later, it was observed that S. invicta ate the epidermis, cortex, phloem and other aboveground stem tissues of E. adenophorum. S. invicta attacked D. orientalis and displaced their living space by causing the later dead, injured, or even disabled. This phenomenon suggested that local herbivorous insects have adapted to E. adenophorum well, which will intensify the naturalization process of E. adenophorum in local habitats. In a homogeneous garden planting experiment of E. adenophorum conducted at the experimental base of Kunming University, the biomass of the introduced (China) populations of E. adenophorum was lower than that of the native (Mexico) populations, although there was no statistically significant difference. These results indicate a possible positive correlation between the increase in natural enemy pressure and the decrease in fitness of E. adenophorum.
基金supported by the National Key R&D Program of China(2021YFD1000500)the Foundation of Guangdong Academy of Agricultural Sciences(R2023PY-JX010)the Natural Science Foundation of Guangdong Province(2021A1515012445).
文摘The insect gustatory system participates in identifying potential food sources and avoiding toxic compounds.During this process,gustatory receptors(GRs)recognize feeding stimulant and deterrent compounds.However,the GRs involved in recognizing stimulant and deterrent compounds in the red imported fire ant,Solenopsis invicta,remain unknown.Therefore,we conducted a study on the genes SinvGR1,SinvGR32b,and SinvGR28a to investigate the roles of GRs in detecting feeding stimulant and deterrent compounds.In this current study,we found that sucrose and fructose are feeding stimulants and the bitter compound quinine is a feeding deterrent.The fire ant workers showed significant behavior changes to avoid the bitter taste in feeding stimulant compounds.Reverse transcription quantitative real-time polymerase chain reaction results from developmental stages showed that the SinvGR1,SinvGR32b,and SinvGR28a genes were highly expressed in fire ant workers.Tissue-specific expression profiles indicated that SinvGR1,SinvGR32b,and SinvGR28a were specifically expressed in the antennae and foreleg tarsi of workers,whereas SinvGR32b gene transcripts were also highly accumulated in the male antennae.Furthermore,the silencing of SinvGRI or SinvGR32b alone and the co-silencing of both genes disrupted worker stimulation and feeding on sucrose and fructose.The results also showed that SinvGR28a is required for avoiding quinine,as workers with knockdown of the SinvGR28a gene failed to avoid and fed on quinine.This study first identified stimulant and deterrent compounds of fire ant workers and then the GRs involved in the taste recognition of these compounds.This study could provide potential target gustatory genes for the control of the fire ant.
文摘红火蚁Solenopsis invicta Buren是全球百种最具危害性的外来入侵物种之一,严重威胁农林业生产、人畜健康、公共安全及生物多样性。精准高效监测红火蚁是其防控的关键,而诱饵诱集是常用的监测手段。本研究在前期已研发的专业监测诱饵内添加5%、10%及15%的NaCl,并测试其储存期及对红火蚁诱集效果的影响,旨在进一步提升诱饵使用效能。结果表明,NaCl浓度越高,诱饵颜色与气味指标降级延迟效应越显著,说明NaCl对诱饵的腐败具有延缓作用。室内测试发现红火蚁的诱集效果总体上随着诱饵储存期的延长而降低,5%NaCl处理在第19天至第25天期间的诱集效果显著高于未添加NaCl的对照,10%NaCl处理仅在第19天、第22天显著,而15%NaCl处理仅在第16天显著。室外测试发现,前20 d NaCl处理与对照差异不显著;第30天,5%NaCl处理的诱集效果显著高于其他处理与对照。综上所述,添加5%NaCl的诱饵在储存期和诱集效果上均表现最佳,可为开发精准高效且低成本的红火蚁监测诱饵提供科学依据。
文摘DNA methylation is accomplished in animals by 2 classes of enzymes known as DNA methyltransferases, DNMT3 and DNMT 1, which perform de novo methylation and maintenance methylation, respectively. Several studies of hymenopteran eusocial insects suggest that DNA methylation is capable of influencing developmental plasticity. However, fundamental questions remain about the patterning of DNA methylation during the course of insect development. In this study, we performed quantitative real-time PCR (qPCR) on transcripts from the single-copy orthologs of DNMT1 and DNMT3 in the red imported fire ant, Solenopsis invicta. In particular, we assessed the expression of S. invicta Dnmtl and Dnmt3 mRNA during 7 stages of worker development, among behaviorally distinct adults, and among male and female gonads. Dnmt3 was most highly expressed during embryonic development, whereas Dnmtl was similarly expressed throughout the course of develop- ment. Moreover, Dnmtl and Dnmt3 were highly expressed in testes and ovaries. Neither Dnmt was significantly differentially expressed among heads of behaviorally distinct adult castes. Our results support the hypothesis that extensive patterning of DNA methylation occurs during gametogenesis and embryogenesis in the insect order Hymenoptera.
文摘One of the most invasive species worldwide, Solenopsis invicta Buren, has been described in China since 2003. Recent studies have suggested that China populations are the result of introductions from the USA; however, detailed molecular studies need to be performed in order to understand the expansion and potential multiple introductions from other countries into China. As there were populations of red imported fire ant, S. invicta in different areas and with different methods of introduction, mitochondrial cytochrome oxidase Ⅰ gene was used as a marker from 12 populations in four cities in Fujian Province, China, to determine the relationship of invasion among these populations. The three most common haplotypes previously describe in invasive populations of S. invicta: H5, H22 and H36, were found in Fujian. However, frequencies in each city were different. For instance, three populations from Longyan city which invaded with waste plastics, shared haplotype H5. Populations from Xiamen city and Jinjiang city which dispersed with nursery stock, sward and scrap leather, shared haplotype H22. The population from Nanyan village of Xinluo district, Longyan city, bore haplotype H36. Mitochondrial data reveals that the invasion history of S. invicta in Fujian Province is complex, including multiple invasions probably from other provinces within China. Security measures to prevent S. invicta spreading within China are as important as from overseas.