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Contribuicao para o estudo das formas larvares de trematodeos parasitas de gastropodes de agua doce em Portugal (nota previa).
1988
Simoes M. | Medeiros L. de
PORTUGUES: E referida a eliminacao de cercarias do tipo Xifidiocercaria em exemplares de Lymnaea peregra (Muller, 1774), colhidos num tanque, em Monchique, Algarve. Os caracois encontravam-se parasitados numa taxa de 97 %, sendo trezentos e oitenta o numero medio de cercarias eliminadas por caracol, em vinte e quatro horas. Sao tambem apresentados alguns aspectos morfologicos e biologicos das formas larvares responsaveis por aquele parasitismo. | It was refered the emergence of cercariae, Xiphidiocercaria type, from samples of Lymnaea (Radix) peregra (Muller, 1774). These snails were collected in a pond, in Monchique (Algarve). On 115 specimens examined 97 % were parasitized. Over a period of 24 hours, 380 cercariae were liberated by snail. Several morphological and biological features of these worms were also presented.
اظهر المزيد [+] اقل [-]Efeito da qualidade da água no ciclo de vida e na atracao para oviposicao de Aedes aegypti (L.) (Diptera: Culicidae) | The effect of water quality in the life cycle and in the attraction for the egg oviposition of Aedes aegypti (L.) (Diptera: Culicidae) النص الكامل
2010
Beserra, Eduardo B. | Fernandes, Carlos R.M. | Sousa, José T. de | Freitas, Eraldo M de | Santos, Keliana D.
The present research aimed at evaluating the influence of the water quality in the life cycle and attraction of Aedes aegypti (L.) females to oviposit using different sources of water (raw sewage, effluent of UASB reactor, effluent of polishing lagoon, effluent of anaerobic filter, rain water and de-chlorinated water). The immature development time and survivorship were evaluated on a daily basis in two distinct feeding systems (with and without food). The quality of the water was shown to affect the egg and larval stages, but not the pupal or the adult. In the absence of food, no development was observed in rain water and de-chlorinated water. Immature development was faster in water sources from raw sewage, although with the lowest survivorship (37.3%). Free-choice tests indicated that females preferred to lay most of their eggs on water collected from the effluent of a UASB reactor, achieving the highest oviposition activity index (OAI) of 0.57. In non-choice tests, females laid larger batches of eggs in water collected from anaerobic filters (204.8 eggs), with the lowest number of eggs being laid on de-chlorinated water (37.3 eggs). It can be concluded that A. aegypti does not demonstrate any particular preference to lay eggs on clean water. This has serious implications for developing strategies to manage populations of this important vector in urban areas as it was shown to lay eggs and successfully develop on several different sources of water.
اظهر المزيد [+] اقل [-][Mortality of third instar Anastrepha striata by immersion in hot water as a function of exposure time and temperature] | Mortalidad de larvas de tercer instar de Anastrepha striata Schiner por inmersion en agua caliente en funcion del tiempo de exposicion y la temperatura.
1998
Matias Hernandez, Dora Maria | Hernandez Ortiz, Emilio | Silva Villarreal, Luis C.
The optimum temperature and exposure time necessary to obtain Probit 9(99.9968 % mortality) for third instar larvae of Anastrepha striata Schiner, when these are immersed in hot water, determined. Treatments were 39.0, 39.6 and 40.0 deg C for periods of 30 to 180 minutes at intervals of 30 min and 42.0 deg C for periods of 30 to 60 minutes at intervals of 10 min. The immersion times estimated to obtain Probit 9 were 154' 53", 137' 50", 124' 41" and 48' 00", respectively. The temperatures estimated to obtain Probit 9 from treatments for 90 and 120 min, were 41.53 and 39.67 deg C, respectively. These results allow to predict the feasibility of applying a quarantine heat treatment for fruits infested with A. striata, as well as to select the time and temperature most appropriate to treat sensitive fruits. | Se determino la temperatura y tiempo optimo de exposicion para obtener la Probita 9 (99.9968 % de mortalidad) para larvas de tercer instar de Anastrepha striata Schiner cuando se sumergen en forma directa en agua caliente. Los tratamientos fueron 39.0, 39.6 y 40.0 grados C por periodos de 30 a 180 minutos en intervalos de 30 min, y 42.0 grados C por periodos de 30 a 60 minutos en intervalos de 10 min. Los tiempos estimados para obtener la Probita 9 fueron 154' 53", 137' 50", 124' 41" y 48' 00", respectivamente. El analisis de los datos de mortalidad obtenidos con los tratamientos con duracion de 90 y 120 minutos estimo temperaturas de 41.53 y 39.67 grados C, respectivamente. Estos resultados permiten predecir la factibilidad de aplicar un tratamiento termico cuarentenario para frutos infestados por A. striata y ademas permiten elegir la dosis de tiempo y temperatura mas adecuada para frutos sensibles.
اظهر المزيد [+] اقل [-]Effect of water quality in mosquito breeding sites on the pathogenicity and infectivity of zoo- spores from the fungus Leptolegnia chapmanii (Straminipila: Peronosporomycetes) | 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) النص الكامل
Effect of water quality in mosquito breeding sites on the pathogenicity and infectivity of zoo- spores from the fungus Leptolegnia chapmanii (Straminipila: Peronosporomycetes) | 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) النص الكامل
2009
Pelizza, Sebastian A. | López Lastra, Claudia C. | Maciá, Arnaldo | Bisaro, Vilma | García, Juan J.
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 Río 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 Río de la Plata pools. Leptolegnia chapmanii was successful as a biological control agent in all kinds of tested water qualities, producing high larval mortality. | Leptolegnia chapmanii es un potente patógeno de larvas de mosquitos. El objetivo del trabajo fue determinar si las características físico-químicas del agua de criaderos de culícidos de importancia sanitaria a nivel mundial afec- tan la patogenicidad e infectividad de las zoosporas de L. chapmanii. Se tomaron muestras de cuatro tipos de agua en Argentina: de lluvia, de zanja, del Río de La Plata, y de floreros del cementerio local. A una parte del agua se le realizaron estudios físicos-químicos, y otra parte fue utilizada en ensayos. Se colocó 150 ml de cada muestra en recipientes plásticos, con 25 larvas sanas de Aedes aegypti y 2.8 x 105 zoosporas de L. chapmanii. Fueron incubadas a 25 oC y 12-12 (L-O). La mortalidad larval fue registrada a las 48 horas. Se utilizaron tres recipientes y un control por tratamiento, con tres repeticiones realizadas en distintos días. Se observaron diferencias altamente significativas entre la mortalidad larval en aguas de floreros del cemen- terio (70.2%), aguas de lluvias (99.53%), y del río de La Plata (95%). No hubo diferencias significativas entre la mortalidad larval en agua de zanja, lluvia y río. Leptolegnia chapmanii resultó exitoso en los cuatro tipos de aguas eva- luados, produciendo elevados niveles de mortalidad larval.
اظهر المزيد [+] اقل [-]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) النص الكامل
2009
Sebastian A Pelizza | Claudia C López Lastra | Arnaldo Maciá | Vilma Bisaro | Juan J García
<abstract language="eng">Effect of water quality in mosquito breeding sites on the pathogenicity and infectivity of zoospores from the fungus Leptolegnia chapmanii (Straminipila: Peronosporomycetes). The fungus Leptolegnia chapmanii is highly pathogenic to mosquito larvae in Argentina. We studied if physical and chemical characteristics 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 Río 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 Río de la Plata pools. Leptolegnia chapmanii was successful as a biological control agent in all kinds of tested water qualities, producing high larval mortality. Rev. Biol. Trop. 57 (1-2): 371-380. Epub 2009 June 30.
اظهر المزيد [+] اقل [-]Efecto de las descargas domésticas y de beneficio de café sobre la calidad del agua y la diversidad de larvas de Odonata (Insecta) en un arroyo de bosque mesófilo de montaña en Veracruz, México النص الكامل
2017
Gómez-Anaya, José Antonio | Novelo-Gutiérrez, Rodolfo | Astudillo-Aldana, Manuel Ricardo
Two contrasting sites along Huehueyapan River (Veracruz, Mexico), one relatively conserved and the other one impacted by domestic and coffee mill discharges, were compared based on water quality data, and the structure of the Odonata larval assemblages. Riparian vegetation of both sites was differentially modified or replaced. Physical and chemical parameters and Odonata larvae were gathered from January to November 2001. A Hotelling-T test was used to compare the physico-chemical parameters while rank/abundance graphs and Renyi diversity profiles were constructed using Odonata larvae data. A total of 2,212 larvae of 13 species in 7 genera were collected. The sites were very similar in number of species and Odonata larval assemblage structure, however, some of the most abundant species at both sites showed significant differences in abundance. The observed differences between the 2 sites are mainly explained by differences in the structure of riparian vegetation and the availability of substrates for odonates and, secondarily, by physical and chemical changes in the water. An abundance ratio was established based on the most abundant species for monitoring future impairment or recovery changes.
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