The community structure of adult mosquitoes was compared from New Jersey light trap collections in six different types of habitats in Citrus County, Florida, USA. From October 1998 to December 2000, mosquitoes were co...The community structure of adult mosquitoes was compared from New Jersey light trap collections in six different types of habitats in Citrus County, Florida, USA. From October 1998 to December 2000, mosquitoes were collected three times a week from the following habitats (swamps, swamps and freshwater marshes, pine fiat-woods, pine fiat-woods and scrub, salt marshes, and salt marshes and mangroves). Mosquito density was highest in the swamps and freshwater marshes habitat, with an average of 95.65 specimens per trap.Density was lowest in the flatwoods and scrub habitat, with an average of 14.38 specimens per trap. Species dominance differed among habitats. Salt marshes produced the greatest aggregation index, while pine flatwoods produced the lowest. Conversely, diversity analysis showed that pine flatwoods had the greatest diversity, while salt marshes the lowest diversity. Similarity indices indicated that the adult mosquito communities from pine flatwoods and pine flatwoods and scrub were very similar (0.8583). The adult mosquito community of salt marshes was different from that of swamps and freshwater marshes (the similar index was 0.0217).展开更多
Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefa...Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefasciatus(Cx.quinquefasciatus) and Aedes albopictus(Ae.albopictus) in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations(2-64μg/mL):the 24 h LC<sub>50</sub> values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC<sub>50</sub>,were studied at different time periods(24-72 h):the extract toxicity was tested against a fish.Oreochromis niloticus(O.niloticus).Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC<sub>50</sub> values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC<sub>50</sub>,significant differences were observed,compared to control groups,in rate of pupation(P【0.001) as well as in adult formation(P【0.001).Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors.展开更多
Objective:To establish an efficacious and efficient surveillance method of Armigeres(Ar.)subalbatus,a known filarial vector,surviving in forest habitats to estimate realistic population density and assess the impact o...Objective:To establish an efficacious and efficient surveillance method of Armigeres(Ar.)subalbatus,a known filarial vector,surviving in forest habitats to estimate realistic population density and assess the impact of altitudinal variations on the efficacy of the trap.Methods:In the study,12 locations in areas with an altitudinal range from 82 m to 920 m were selected in three reserve forests for night sampling of adult Ar.subalbatus mosquito using standard chemical lure based BG-Sentinel traps and CDC-light traps in pairs.Effects of locations and time were estimated on the efficacy of traps as mosquito density using multifactor analysis of variance for significant differences.Impact of altitudinal variations on the efficacy of traps was assessed using multiple regression with slope comparison.Results:BG-Sentinel trap collected significantly more adult Ar.subalbatus,4.43 folds in Gorumara NP,5.19 folds in Neora Valley NP and 12.10 folds in Mahananda WLS than the CDC-light trap irrespective to locations.BG-Sentinel traps were tolerant of altitudinal variations(80 m-170 m)and showed no significant relationship between density and altitudes in contrast to CDC-light traps which showed a significant negative impact on capturing efficacy with increase in altitudes(P<0.001).Conclusions:The study suggests that BG-Sentinel traps can be used effectively and efficiently to collect more Ar.subalbatus mosquitoes during night time in comparison to CDC-light trap under complex climatic conditions of forest and variable altitudes.展开更多
Objective:To evaluate the adulticidal activity and toxicity of different solvent crude extracts of Delonix elata(D.elata)against filariasis vector mosquito Culex quinquefasciatus(Cx.quinquefasciatus).Methods:The adult...Objective:To evaluate the adulticidal activity and toxicity of different solvent crude extracts of Delonix elata(D.elata)against filariasis vector mosquito Culex quinquefasciatus(Cx.quinquefasciatus).Methods:The adulticidal activities of crude hexane,benzene,ethyl acetate,chloroform and methanol leaf and seed extracts of D.elata were assayed for their toxicity against vector mosquitoCx.quinquefasciatus.Bioassay was carried out by WHO method for determination of adulticidal activity against mosquitoes.The adult mortality was observed after 24 h of exposure.Results:All extracts showed moderate adulticidal effects;however,the highest adult mortality was found in methanol extract of D.elata leaf against the adults of Cx.quinquefasciatus with the LC_(50) and LC_(90) values at 197.28 and 347.45mg/L,respectively.Conclusions:These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes.This study provides first report on the mosquito adulticidal activity of D.elata plant extracts against filariasis vector mosquito,Cx.quinquefasciatus.展开更多
文摘The community structure of adult mosquitoes was compared from New Jersey light trap collections in six different types of habitats in Citrus County, Florida, USA. From October 1998 to December 2000, mosquitoes were collected three times a week from the following habitats (swamps, swamps and freshwater marshes, pine fiat-woods, pine fiat-woods and scrub, salt marshes, and salt marshes and mangroves). Mosquito density was highest in the swamps and freshwater marshes habitat, with an average of 95.65 specimens per trap.Density was lowest in the flatwoods and scrub habitat, with an average of 14.38 specimens per trap. Species dominance differed among habitats. Salt marshes produced the greatest aggregation index, while pine flatwoods produced the lowest. Conversely, diversity analysis showed that pine flatwoods had the greatest diversity, while salt marshes the lowest diversity. Similarity indices indicated that the adult mosquito communities from pine flatwoods and pine flatwoods and scrub were very similar (0.8583). The adult mosquito community of salt marshes was different from that of swamps and freshwater marshes (the similar index was 0.0217).
文摘Objective:To determine the larvicidal and adult emergence inhibition activities of castor (Ricinus communis) seed extract against three potential mosquito vectors Anopheles stephensi(An. slephensi),Culex quinquefasciatus(Cx.quinquefasciatus) and Aedes albopictus(Ae.albopictus) in India.Methods:The R.communis seed extract was tested,employing WHO procedure,against fourth larval instars of the three mosquito species for 24 h and larval mortalities were recorded at various concentrations(2-64μg/mL):the 24 h LC<sub>50</sub> values of the R.communis seed extract were determined following Probit analysis.The larval killing,antipupation and adult emergence inhibition rates of the test extract,using a single concentration of 2μLC<sub>50</sub>,were studied at different time periods(24-72 h):the extract toxicity was tested against a fish.Oreochromis niloticus(O.niloticus).Results:The R.communis seed extract exhibited larvicidal effects with 100%killing activities at concentrations 32-64μg/mL,and with LC<sub>50</sub> values 7.10.11.64 and 16.84μg/mL for Cx.quinquefasciatus,An.stephensi and Ae.albopictus larvae,respectively. When the larvae were treated with the extract at a single concentration of 2×LC<sub>50</sub>,significant differences were observed,compared to control groups,in rate of pupation(P【0.001) as well as in adult formation(P【0.001).Conclusions:The present findings suggest that the R.communis seed extract provided an excellent potential for controlling An.stephensi,Cx.quinquefasciatus and Ae. albopictus mosquito vectors.
基金Dr.Kailash Chandra,Director,Zoological Survey of India(ZSI),Ministry of Environment,Forest and Climate Change(MoEFCC),Govt.of India,for providing funding and logistic support.
文摘Objective:To establish an efficacious and efficient surveillance method of Armigeres(Ar.)subalbatus,a known filarial vector,surviving in forest habitats to estimate realistic population density and assess the impact of altitudinal variations on the efficacy of the trap.Methods:In the study,12 locations in areas with an altitudinal range from 82 m to 920 m were selected in three reserve forests for night sampling of adult Ar.subalbatus mosquito using standard chemical lure based BG-Sentinel traps and CDC-light traps in pairs.Effects of locations and time were estimated on the efficacy of traps as mosquito density using multifactor analysis of variance for significant differences.Impact of altitudinal variations on the efficacy of traps was assessed using multiple regression with slope comparison.Results:BG-Sentinel trap collected significantly more adult Ar.subalbatus,4.43 folds in Gorumara NP,5.19 folds in Neora Valley NP and 12.10 folds in Mahananda WLS than the CDC-light trap irrespective to locations.BG-Sentinel traps were tolerant of altitudinal variations(80 m-170 m)and showed no significant relationship between density and altitudes in contrast to CDC-light traps which showed a significant negative impact on capturing efficacy with increase in altitudes(P<0.001).Conclusions:The study suggests that BG-Sentinel traps can be used effectively and efficiently to collect more Ar.subalbatus mosquitoes during night time in comparison to CDC-light trap under complex climatic conditions of forest and variable altitudes.
基金Supported by the University Grants Commission(UGC)(F.No.39-646/2010(SR)),New Delhi,India.
文摘Objective:To evaluate the adulticidal activity and toxicity of different solvent crude extracts of Delonix elata(D.elata)against filariasis vector mosquito Culex quinquefasciatus(Cx.quinquefasciatus).Methods:The adulticidal activities of crude hexane,benzene,ethyl acetate,chloroform and methanol leaf and seed extracts of D.elata were assayed for their toxicity against vector mosquitoCx.quinquefasciatus.Bioassay was carried out by WHO method for determination of adulticidal activity against mosquitoes.The adult mortality was observed after 24 h of exposure.Results:All extracts showed moderate adulticidal effects;however,the highest adult mortality was found in methanol extract of D.elata leaf against the adults of Cx.quinquefasciatus with the LC_(50) and LC_(90) values at 197.28 and 347.45mg/L,respectively.Conclusions:These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes.This study provides first report on the mosquito adulticidal activity of D.elata plant extracts against filariasis vector mosquito,Cx.quinquefasciatus.