The Experts below are selected from a list of 102 Experts worldwide ranked by ideXlab platform
Juan J. García - One of the best experts on this subject based on the ideXlab platform.
-
Leptolegnia chapmanii straminipila peronosporomycetes as a future biorational tool for the control of aedes aegypti l
Acta Tropica, 2017Co-Authors: Alejandra Concepcion Gutierrez, C Lopez C Lastra, M Rueda E Paramo, M L Falvo, Juan J. GarcíaAbstract:The aim of the present review is to summarize the current knowledge about Leptolegnia chapmanii as a pathogen of mosquito larvae. To this end, we present data on its identification, distribution, host range and effects on non-target organisms, effects of environmental factors, in vitro growth, release and persistence in anthropic environments, and effect combined with other insecticides. The data presented allow confirming its potential as a biocontrol agent.
-
effect of ultraviolet a radiation on the production of Leptolegnia chapmanii saprolegniales saprolegniaceae zoospores on dead aedes aegypti diptera culicidae larvae and their larvicidal activity
Journal of Invertebrate Pathology, 2015Co-Authors: Juan J. García, Everton K K Fernandes, Claudia Lopez C Lastra, Manuel Enrique Rueda Paramo, Ricardo Neves MarretoAbstract:Abstract Impact of UV-radiation in entomopathogens in aquatic environments remains little investigated. The present study reports on the effect of UV-A on the larvicidal activity of Leptolegnia chapmanii zoospores in Aedes aegypti; on the production of zoospores in larvae killed by the pathogen and then exposed to UV-A; and on the activity of these zoospores against healthy larvae. Whereas the virulence of free zoospores in A. aegypti larvae was affected by a UV-A exposure time longer than 10 min, production of zoospores in larvae and their virulence were not hampered at a maximal 8 h exposure of dead larvae to UV-A. Findings suggest that dead larvae and zoosporangia provide a certain protection to zoospores against UV-A and emphasize the susceptibility of free encysted zoospores to such radiation.
-
persistence and pathogenicity of a native isolate of Leptolegnia chapmanii against aedes aegypti larvae in different anthropic environments
Biocontrol Science and Technology, 2015Co-Authors: Manuel Enrique Rueda Paramo, Claudia Lopez C Lastra, Juan J. GarcíaAbstract:The oomycete Leptolegnia chapmanii has been identified as a potential control agent of the primary vector of dengue, Aedes aegypti. In our assays, the persistence and pathogenicity of a native isolate of L. chapmanii decreased over time regardless of location. However, the mortality of Ae. aegypti larvae was significantly lower (p < 0.05) in containers located outside without sun protection (89% at first week and 9% at sixth week) compared with the containers located indoors (97% at first week and 42% at sixth week) and outside with shade (89% at first week and 29% at sixth week) possibly because of exposure to sun radiation.
-
efecto de la calidad del agua de criaderos de mosquitos diptera culicidae sobre la patogenicidad e infectividad de las zoosporas del hongo Leptolegnia chapmanii straminipila peronosporomycetes
Revista De Biologia Tropical, 2013Co-Authors: Sebastian A. Pelizza, Vilma Bisaro, Claudia Lopez C Lastra, Arnaldo Macia, Juan J. GarcíaAbstract:The fungus Leptolegnia chapmanii is highly pathogenic to mosquito larvae in Argentina. We studied if physical and chemical charac- teristics of the water from mosquito breeding sites affect pathogenicity, and the infectivity of zoospores of L. chapmanii. Water samples were taken from pools filled by rains, urban ditches with domestic waste water, pools filled by overflow from Rio de la Plata, and flower vases from the Cemetery of La Plata city. Sub-samples of water were analyzed for physical and chemical characteristics, while other sub-samples were used for laboratory bioassays. Containers with 150 ml of water samples, 25 Aedes aegypti larvae, and 2.8 x 105 zoospores of L. chapmanii, were incubated under controlled environment, and larval mortality was recorded after 48 h. There were highly significant differences among mortalities in water from cemetery vases (70.2%), rain pools water (99.5%), and pools with water from Rio de la Plata (95%). There were no significant differences among larval mortalities in water from ditches, rain pools and Rio de la Plata pools. Leptolegnia chapmanii was successful as a biological control agent in all kinds of tested water qualities, producing high larval mortality.
-
individual and combined effects of bacillus thuringiensis var israelensis temephos and Leptolegnia chapmanii on the larval mortality of aedes aegypti
Biocontrol, 2010Co-Authors: Sebastian A. Pelizza, Ana C. Scorsetti, Vilma Bisaro, Claudia Lopez C Lastra, Juan J. GarcíaAbstract:Larvicidal effects of interaction between Bacillus thuringiensis var. israelensis (Bti), temephos and Leptolegnia chapmanii zoospores on larvae of Aedes aegypti were determined under laboratory and seminatural conditions. In laboratory bioassays, two concentrations of Bti (0.012, 0.027 ppm), two of temephos (0.00035, 0.001 ppm), and a single concentration of L. chapmanii zoospores (6.1 × 104 zoospores ml−1) were evaluated. Trials under field-like conditions were performed in a single container and then placed either in the shade or in direct exposure to sunlight. We evaluated concentrations of Bti and temephos at 3-fold those normally used in laboratory tests: 0.09 and 0.003 ppm, respectively, plus 1.8 × 105 zoospores ml−1 of L. chapmanii. The combined effect of sublethal concentrations of Bti, temephos, and L. chapmanii zoospores thus indicated that this fungus is not inhibited by the larvicides and also demonstrated the synergistic effect of the action of L. chapmanii when used together with Bti and temephos.
Sebastian A. Pelizza - One of the best experts on this subject based on the ideXlab platform.
-
incipient loss of flagella in the genus geolegnia the emergence of a new clade within Leptolegnia
IMA fungus, 2013Co-Authors: Monica Mirta Steciow, Sebastian A. Pelizza, Enrique Lara, Amandine Pillonel, Eduardo Ariel Lestani, Gustavo Carlos Rossi, Lassaad BelbahriAbstract:The genus Geolegnia represents a poorly documented group of saprolegnialean oomycetes isolated from soils as free-living organisms. Although it is morphologically similar to the facultative parasitic genus Leptolegnia, Geolegnia presents the uncommon property of having lost a flagellate stage in its lifecycle. Based on ITS and large subunit (LSU) rRNA sequence data, we show Geolegnia to be basal to Leptolegnia, and also introduce Geolegnia helicoides sp. nov. Using sequence data of Leptolegnia available in GenBank, supplemented by data derived from culture collections, we show that Geolegnia is nested within Leptolegnia, a genus characterised by its “conventional” biflagellate life cycle. The emergence of Geolegnia is therefore seen as a recent event, and we suggest here an evolutionary context where this loss might have been advantageous. Based on this study, Leptolegnia remains paraphyletic, awaiting the redefinition of genera in this complex.
-
efecto de la calidad del agua de criaderos de mosquitos diptera culicidae sobre la patogenicidad e infectividad de las zoosporas del hongo Leptolegnia chapmanii straminipila peronosporomycetes
Revista De Biologia Tropical, 2013Co-Authors: Sebastian A. Pelizza, Vilma Bisaro, Claudia Lopez C Lastra, Arnaldo Macia, Juan J. GarcíaAbstract:The fungus Leptolegnia chapmanii is highly pathogenic to mosquito larvae in Argentina. We studied if physical and chemical charac- teristics of the water from mosquito breeding sites affect pathogenicity, and the infectivity of zoospores of L. chapmanii. Water samples were taken from pools filled by rains, urban ditches with domestic waste water, pools filled by overflow from Rio de la Plata, and flower vases from the Cemetery of La Plata city. Sub-samples of water were analyzed for physical and chemical characteristics, while other sub-samples were used for laboratory bioassays. Containers with 150 ml of water samples, 25 Aedes aegypti larvae, and 2.8 x 105 zoospores of L. chapmanii, were incubated under controlled environment, and larval mortality was recorded after 48 h. There were highly significant differences among mortalities in water from cemetery vases (70.2%), rain pools water (99.5%), and pools with water from Rio de la Plata (95%). There were no significant differences among larval mortalities in water from ditches, rain pools and Rio de la Plata pools. Leptolegnia chapmanii was successful as a biological control agent in all kinds of tested water qualities, producing high larval mortality.
-
the sublethal effects of the entomopathic fungus Leptolegnia chapmanii on some biological parameters of the dengue vector aedes aegypti
Journal of Insect Science, 2013Co-Authors: Sebastian A. Pelizza, Ana C. Scorsetti, Maria Cecilia TranchidaAbstract:The mosquito Aedes aegypti (L.) (Diptera: Culicidae) is the primary vector of dengue in the Americas. The use of chemical insecticides is recommended during outbreaks of dengue in order to reduce the number of adult mosquitoes; however, because Ae. aegypti is highly synanthropic, the use of insecticides in densely populated areas is a dangerous practice. Leptolegnia chapmanii Seymour (Straminipila: Peronosporomycetes) is an entomopathogenic microorganism that has demonstrated marked pathogenicity toward the larvae of a number of mosquito species, with little or no effect on non-target insects. Therefore, the purpose of this study was to determine the sublethal effects of L. chapmanii on fecundity, number of gonotrophic cycles, fertility, and relationship between wing length and fecundity in Ae. aegypti females. Ae. aegypti females that survived infection with L. chapmanii laid fewer eggs, had a smaller number of gonotrophic cycles, had shorter wings, and were less fertile than controls. This is the first study on the sublethal effects experienced by specimens of Ae. aegypti that survived infection with zoospores of L. chapmanii. Although field studies should be carried out, the results obtained in this study are encouraging because the high and rapid larval mortality caused by L. chapmanii coupled with the reduction of reproductive capacity in Ae. aegypti females seem to cause a significant reduction in the number of adults in the mid and long term, thereby reducing the health risks associated with Ae. aegypti.
-
screening for a culture medium yielding optimal colony growth zoospore yield and infectivity of different isolates of Leptolegnia chapmanii straminipila peronosporomycetes
Annals of Microbiology, 2011Co-Authors: Sebastian A. Pelizza, Ana C. Scorsetti, Marta Noemi Cabello, Maria Cecilia Tranchida, Vilma BisaroAbstract:Leptolegnia chapmanii is an aquatic fungus that has demonstrated marked pathogenicity towards the larvae of a number of mosquito species with little or no effect on non-target insects. The aim of this work was to determine the best culture medium for colony growth, and production and infectivity of zoospores among different isolates of L. chapmanii. No significant differences (P >0.01) were observed for the media FORT(agar), PYG, YPSS, and PYGSF in terms of colony diameter of the different isolates evaluated. In these culture media, all L. chapmanii isolates had the highest growth (45 mm2) after 7 days. The nine isolates tested produced the greatest number of zoospores in FORT(agar) medium 3 (1 × 106 zoospores/ml). Medium YPSS exhibited significant differences (P <0.0001) compared to other culture media with respect to maintenance of virulence and infectivity of the isolates, producing 100% larval mortality after 48 h of inoculation. Thus, for the cultivation and maintenance of L. chapmanii isolates, the medium of choice among those tested is FORT(agar), as it is both inexpensive to prepare and ensures optimal colony development, extremely high zoospore production, and excellent maintenance of fungal infectivity.
-
individual and combined effects of bacillus thuringiensis var israelensis temephos and Leptolegnia chapmanii on the larval mortality of aedes aegypti
Biocontrol, 2010Co-Authors: Sebastian A. Pelizza, Ana C. Scorsetti, Vilma Bisaro, Claudia Lopez C Lastra, Juan J. GarcíaAbstract:Larvicidal effects of interaction between Bacillus thuringiensis var. israelensis (Bti), temephos and Leptolegnia chapmanii zoospores on larvae of Aedes aegypti were determined under laboratory and seminatural conditions. In laboratory bioassays, two concentrations of Bti (0.012, 0.027 ppm), two of temephos (0.00035, 0.001 ppm), and a single concentration of L. chapmanii zoospores (6.1 × 104 zoospores ml−1) were evaluated. Trials under field-like conditions were performed in a single container and then placed either in the shade or in direct exposure to sunlight. We evaluated concentrations of Bti and temephos at 3-fold those normally used in laboratory tests: 0.09 and 0.003 ppm, respectively, plus 1.8 × 105 zoospores ml−1 of L. chapmanii. The combined effect of sublethal concentrations of Bti, temephos, and L. chapmanii zoospores thus indicated that this fungus is not inhibited by the larvicides and also demonstrated the synergistic effect of the action of L. chapmanii when used together with Bti and temephos.
Claudia Lopez C Lastra - One of the best experts on this subject based on the ideXlab platform.
-
compatibility between Leptolegnia chapmanii and diflubenzuron and neem oil for the control of aedes aegypti
Revista Argentina De Microbiologia, 2020Co-Authors: Manuel Enrique Rueda Paramo, Marianel Lucia Falvo, Juan Agustin Garcia, Claudia Lopez C LastraAbstract:Leptolegnia chapmanii is pathogenic to mosquito larvae. The compatibility between L. chapmanii and two insect growth regulators (IGR), diflubenzuron and neem oil, was evaluated. L. chapmanii was grown on culture media containing different concentrations of each IGR. The mycelial growth was significantly reduced with the highest concentrations of IGR (F6,98=268, p 0.05) and the larval mortality of Aedes aegypti (F6,56=0.95, p>0.05) were not significantly different among treatments. Furthermore, the percentage of adult emergence in the presence of different concentrations of diflubenzuron or a neem formulation was determined, and the pathogenic activity of zoospores was evaluated at the concentrations that inhibit the emergence at 30, 50 and 90%. The pathogenicity of zoospores was not significantly different among treatments (F6,14=0.54, p>0.05), and the larval mortalities were above 90% in all cases.
-
impact of short term temperature challenges on the larvicidal activities of the entomopathogenic watermold Leptolegnia chapmanii against aedes aegypti and development on infected dead larvae
Fungal Biology, 2018Co-Authors: Claudia Lopez C Lastra, J. J. García, Elen Regozino Muniz, Alaine M L Catao, Manuel E Ruedaparamo, Juscelino Rodrigues, Everton K K FernandesAbstract:Abstract The oomycete Leptolegnia chapmanii is among the most promising entomopathogens for biological control of Aedes aegypti. This mosquito vector breeds in small water collections, where this aquatic watermold pathogen can face short-term scenarios of challenging high or low temperatures during changing ambient conditions, but it is yet not well understood how extreme temperatures might affect the virulence and recycling capacities of this pathogen. We tested the effect of short-term exposure of encysted L. chapmanii zoospores (cysts) on A. aegypti larvae killed after infection by this pathogen to stressful low or high temperatures on virulence and production of cysts and oogonia, respectively. Cysts were exposed to temperature regimes between −12 °C and 40 °C for 4, 6 or 8 h, and then their infectivity was tested against third instar larvae (L3) at 25 °C; in addition, production of cysts and oogonia on L3 killed by infection exposed to the same temperature regimes as well as their larvicidal activity were monitored. Virulence of cysts to larvae and the degree of zoosporogenesis on dead larvae under laboratory conditions were highest at 25 °C but were hampered or even blocked after 4 up to 8 h exposure of cysts or dead larvae at both the highest (35 °C and 40 °C) and the lowest (−12 °C) temperatures followed by subsequent incubation at 25 °C. The virulence of cysts was less affected by accelerated than by slow thawing from the frozen state. The production of oogonia on dead larvae was stimulated by short-term exposure to freezing temperatures (−12 °C and 0 °C) or cool temperatures (5 °C and 10 °C) but was not detected at higher temperatures (25 °C–40 °C). These findings emphasize the susceptibility of L. chapmanii to short-term temperature stresses and underscore its interest as an agent for biocontrol of mosquitoes in the tropics and subtropics, especially A. aegypti, that breed preferentially in small volumes of water that are generally protected from direct sunlight.
-
development of the mosquito pathogen Leptolegnia chapmanii straminipila peronosporomycetes on an inexpensive culture medium based on sunflower seed
Biocontrol Science and Technology, 2016Co-Authors: Manuel Enrique Rueda Paramo, Claudia Lopez C Lastra, Romina Guadalupe Manfrino, Alejandra Concepcion Gutierrez, J. J. GarcíaAbstract:ABSTRACTAn inexpensive culture medium based on sunflower seed extract (SSE) for production of Leptolegnia chapmanii was developed. Vegetative growth on solid and liquid SSE was compared with two culture media used routinely (peptone, yeast and glucose (PYG) and Emerson YPss). Results indicate that the oomycete is able to grow on SSE medium, producing more zoospores at a faster rate as well as inducing higher mortality rates in Aedes aegypti larvae.
-
effect of ultraviolet a radiation on the production of Leptolegnia chapmanii saprolegniales saprolegniaceae zoospores on dead aedes aegypti diptera culicidae larvae and their larvicidal activity
Journal of Invertebrate Pathology, 2015Co-Authors: Juan J. García, Everton K K Fernandes, Claudia Lopez C Lastra, Manuel Enrique Rueda Paramo, Ricardo Neves MarretoAbstract:Abstract Impact of UV-radiation in entomopathogens in aquatic environments remains little investigated. The present study reports on the effect of UV-A on the larvicidal activity of Leptolegnia chapmanii zoospores in Aedes aegypti; on the production of zoospores in larvae killed by the pathogen and then exposed to UV-A; and on the activity of these zoospores against healthy larvae. Whereas the virulence of free zoospores in A. aegypti larvae was affected by a UV-A exposure time longer than 10 min, production of zoospores in larvae and their virulence were not hampered at a maximal 8 h exposure of dead larvae to UV-A. Findings suggest that dead larvae and zoosporangia provide a certain protection to zoospores against UV-A and emphasize the susceptibility of free encysted zoospores to such radiation.
-
persistence and pathogenicity of a native isolate of Leptolegnia chapmanii against aedes aegypti larvae in different anthropic environments
Biocontrol Science and Technology, 2015Co-Authors: Manuel Enrique Rueda Paramo, Claudia Lopez C Lastra, Juan J. GarcíaAbstract:The oomycete Leptolegnia chapmanii has been identified as a potential control agent of the primary vector of dengue, Aedes aegypti. In our assays, the persistence and pathogenicity of a native isolate of L. chapmanii decreased over time regardless of location. However, the mortality of Ae. aegypti larvae was significantly lower (p < 0.05) in containers located outside without sun protection (89% at first week and 9% at sixth week) compared with the containers located indoors (97% at first week and 42% at sixth week) and outside with shade (89% at first week and 29% at sixth week) possibly because of exposure to sun radiation.
C Lopez C Lastra - One of the best experts on this subject based on the ideXlab platform.
-
Leptolegnia chapmanii straminipila peronosporomycetes as a future biorational tool for the control of aedes aegypti l
Acta Tropica, 2017Co-Authors: Alejandra Concepcion Gutierrez, C Lopez C Lastra, M Rueda E Paramo, M L Falvo, Juan J. GarcíaAbstract:The aim of the present review is to summarize the current knowledge about Leptolegnia chapmanii as a pathogen of mosquito larvae. To this end, we present data on its identification, distribution, host range and effects on non-target organisms, effects of environmental factors, in vitro growth, release and persistence in anthropic environments, and effect combined with other insecticides. The data presented allow confirming its potential as a biocontrol agent.
-
effects of temperature ph and salinity on the infection of Leptolegnia chapmanii seymour peronosporomycetes in mosquito larvae
Journal of Invertebrate Pathology, 2007Co-Authors: Sebastian A. Pelizza, C Lopez C Lastra, Vilma Bisaro, James J Becnel, Juan J. GarcíaAbstract:The effects of temperature, pH, and NaCl concentrations on the infectivity of zoospores of Leptolegnia chapmanii (Argentine isolate) were determined for Aedes aegypti and Culex pipiens under laboratory conditions. Zoospores of L. chapmanii were infectious at temperatures between 10 and 35 degrees C but not at 5 or 40 degrees C. At the permissive temperatures, mortality rates in young instars were much higher than in older instars and larvae of Ae. aegypti were more susceptible to L. chapmanii than larvae of Cx. pipiens. At 25 degrees C, Ae. aegypti larvae challenged with L. chapmanii zoospores resulted in 100% infection at pH levels ranging from 4 to 10. Larvae of Cx. pipiens exposed to similar pH and zoospore concentrations resulted in increasing mortality rates from 62% to 99% at pH 4 to 7, respectively, and then decreased to 71% at pH 10. Aedes aegypti larvae exposed to L. chapmanii zoospores in NaCl concentrations ranging from 0 to 7 parts per thousand (ppt) at 25 degrees C resulted in 100% mortality while mortality rates for Cx. pipiens decreases from 96% in distilled water to 31.5% in water with 6 ppt NaCl. Control Cx. pipiens larvae died when exposed at a NaCl concentration of 7 ppt. Vegetative growth of L. chapmanii was negatively affected by NaCl concentrations. These results have demonstrated that the Argentinean isolate of L. chapmanii tolerated a wide range of temperatures, pH, and salinity, suggesting that it has the potential to adapt to a wide variety of mosquito habitats.
-
evaluation of histological techniques for the detection of fungal infections caused by Leptolegnia chapmanii oomycetes saprolegniales in aedes aegypti diptera culicidae larvae
Folia Microbiologica, 2005Co-Authors: V. E. Dikgolz, A. V. Toledo, P. E. Topa, C Lopez C LastraAbstract:We evaluated which of the fixatives and stains most frequently used for observation of insect tissues were the most appropriate for histopathological visualization of entomopathogenic fungal infections withLeptolegnia chapmanii in larvae ofAedes aegypti. The best contrast between the host tissues and the fungal structures was obtained when using a combination of Carnoy fixative with Grocott staining contrasted with light green. Masson trichromic stain combined with 10% formaldehyde-phosphate buffer also provided satisfactory results — a good contrast and clearly distinguishable host tissues and fungal structures.
-
southernmost record of the fungus Leptolegnia chapmanii oomycetes saprolegniales as a mosquito larvae pathogen diptera culicidae
Revista Iberoamericana De Micologia, 1999Co-Authors: C Lopez C Lastra, Monica Mirta Steciow, Juan J. GarcíaAbstract:: In the present paper we communicate the southernmost record and the first for the neotropical region of the fungus Leptolegnia chapmanii (Oomycetes: Saprolegniales) as a mosquito larvae pathogen, in Buenos Aires, Argentina. The fungal description is extended as the host range and geographic distribution.
Manuel Enrique Rueda Paramo - One of the best experts on this subject based on the ideXlab platform.
-
compatibility between Leptolegnia chapmanii and diflubenzuron and neem oil for the control of aedes aegypti
Revista Argentina De Microbiologia, 2020Co-Authors: Manuel Enrique Rueda Paramo, Marianel Lucia Falvo, Juan Agustin Garcia, Claudia Lopez C LastraAbstract:Leptolegnia chapmanii is pathogenic to mosquito larvae. The compatibility between L. chapmanii and two insect growth regulators (IGR), diflubenzuron and neem oil, was evaluated. L. chapmanii was grown on culture media containing different concentrations of each IGR. The mycelial growth was significantly reduced with the highest concentrations of IGR (F6,98=268, p 0.05) and the larval mortality of Aedes aegypti (F6,56=0.95, p>0.05) were not significantly different among treatments. Furthermore, the percentage of adult emergence in the presence of different concentrations of diflubenzuron or a neem formulation was determined, and the pathogenic activity of zoospores was evaluated at the concentrations that inhibit the emergence at 30, 50 and 90%. The pathogenicity of zoospores was not significantly different among treatments (F6,14=0.54, p>0.05), and the larval mortalities were above 90% in all cases.
-
development of the mosquito pathogen Leptolegnia chapmanii straminipila peronosporomycetes on an inexpensive culture medium based on sunflower seed
Biocontrol Science and Technology, 2016Co-Authors: Manuel Enrique Rueda Paramo, Claudia Lopez C Lastra, Romina Guadalupe Manfrino, Alejandra Concepcion Gutierrez, J. J. GarcíaAbstract:ABSTRACTAn inexpensive culture medium based on sunflower seed extract (SSE) for production of Leptolegnia chapmanii was developed. Vegetative growth on solid and liquid SSE was compared with two culture media used routinely (peptone, yeast and glucose (PYG) and Emerson YPss). Results indicate that the oomycete is able to grow on SSE medium, producing more zoospores at a faster rate as well as inducing higher mortality rates in Aedes aegypti larvae.
-
effect of ultraviolet a radiation on the production of Leptolegnia chapmanii saprolegniales saprolegniaceae zoospores on dead aedes aegypti diptera culicidae larvae and their larvicidal activity
Journal of Invertebrate Pathology, 2015Co-Authors: Juan J. García, Everton K K Fernandes, Claudia Lopez C Lastra, Manuel Enrique Rueda Paramo, Ricardo Neves MarretoAbstract:Abstract Impact of UV-radiation in entomopathogens in aquatic environments remains little investigated. The present study reports on the effect of UV-A on the larvicidal activity of Leptolegnia chapmanii zoospores in Aedes aegypti; on the production of zoospores in larvae killed by the pathogen and then exposed to UV-A; and on the activity of these zoospores against healthy larvae. Whereas the virulence of free zoospores in A. aegypti larvae was affected by a UV-A exposure time longer than 10 min, production of zoospores in larvae and their virulence were not hampered at a maximal 8 h exposure of dead larvae to UV-A. Findings suggest that dead larvae and zoosporangia provide a certain protection to zoospores against UV-A and emphasize the susceptibility of free encysted zoospores to such radiation.
-
persistence and pathogenicity of a native isolate of Leptolegnia chapmanii against aedes aegypti larvae in different anthropic environments
Biocontrol Science and Technology, 2015Co-Authors: Manuel Enrique Rueda Paramo, Claudia Lopez C Lastra, Juan J. GarcíaAbstract:The oomycete Leptolegnia chapmanii has been identified as a potential control agent of the primary vector of dengue, Aedes aegypti. In our assays, the persistence and pathogenicity of a native isolate of L. chapmanii decreased over time regardless of location. However, the mortality of Ae. aegypti larvae was significantly lower (p < 0.05) in containers located outside without sun protection (89% at first week and 9% at sixth week) compared with the containers located indoors (97% at first week and 42% at sixth week) and outside with shade (89% at first week and 29% at sixth week) possibly because of exposure to sun radiation.