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Sandra Vacas - One of the best experts on this subject based on the ideXlab platform.
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mating disruption for the control of aonidiella aurantii maskell hemiptera diaspididae may contribute to increased effectiveness of natural enemies
Pest Management Science, 2012Co-Authors: Sandra Vacas, Pilar Vanaclocha, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: New directives on sustainable use of pesticides have encouraged research on efficient alternative pest control methods. In the case of the California red scale (CRS), Aonidiella aurantii (Maskell), this imperative, along with the many difficulties in controlling this pest, have led to the investigation of new approaches. Previously developed mating disruption (MD) dispensers, together with the augmentative releases of the parasitoid Aphytis melinus DeBach, are here considered as a combined strategy for use against A. aurantii. RESULTS: Efficacy of MD was demonstrated by a mean reduction of 80% in CRS male catches and a mean fruit damage reduction of 83% compared with the control. A delay in the development of A. aurantii instars was observed in the MD plot. This delay increased the period of exposure of the susceptible instars to natural enemies, which resulted in higher predation and parasitism levels in the MD plot. Under laboratory conditions, A. melinus mating behaviour and effects on A. aurantii were not significantly altered in a CRS-pheromone-saturated environment. CONCLUSION: Mating disruption pheromone did not affect the behaviour or level of parasitism by A. melinus or the incidence of other generalist predators. Therefore, A. aurantii pheromone appears to be compatible with augmentative releases and biological control, making its use a good strategy for CRS management. Copyright © 2011 Society of Chemical Industry
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mating disruption of california red scale aonidiella aurantii maskell homoptera diaspididae using biodegradable mesoporous pheromone dispensers
Pest Management Science, 2010Co-Authors: Sandra Vacas, Cristina Alfaro, Vicente Navarrollopis, Jaime PrimoAbstract:BACKGROUND: The control of California red scale, Aonidiella aurantii (Maskell), has encountered many difficulties, which has raised interest in alternative control methods. Up to now, the A. aurantii sex pheromone has been used only for monitoring. In a previous work the authors described a biodegradable mesoporous pheromone dispenser for mating disruption. To verify the efficacy of these dispensers, three field trials were conducted, and the results are shown in this paper. RESULTS: The study of the release profile of these dispensers revealed a mean pheromone emission value of 269 µg day−1 and levels of residual pheromone of 10% at the end of 250 days. During the second flight, an A. aurantii male catch reduction of 98% was achieved in the mating disruption plot of trial 1, 93.5% in trial 2 and 76.7% in trial 3. During the third flight, reductions were 94.1, 82.9 and 68.1% in trials 1, 2 and 3 respectively. Considering damaged fruit with more than five scales, reductions of about 80 and 60% were obtained in the mating disruption plots of trials 2 and 3, respectively, compared with an untreated plot, and a reduction of about 70% in trial 1 compared with an oil-treated plot. CONCLUSION: Mating disruption has been found to be an efficient technique to control this pest, working equally well to a correctly sprayed oil treatment. Further studies are needed to improve the determination of the time of dispenser application and evaluate the effects of the pheromone on natural enemies. Copyright © 2010 Society of Chemical Industry
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the first account of the mating disruption technique for the control of california red scale aonidiella aurantii maskell homoptera diaspididae using new biodegradable dispensers
Bulletin of Entomological Research, 2009Co-Authors: Sandra VacasAbstract:Semiochemical-based pest management programs have been increasingly used to provide environmentally friendly methods for the control of major insect pests. The efficacy of the mating disruption technique has been demonstrated for several moth pests. Unfortunately, not many experiments on mating disruption to control diaspididae species have been documented. In this work, biodegradable dispensers for mating disruption with increasing pheromone loads were used in order to study the potential of this technique for the control of Aonidiella aurantii Maskell. Field trial results demonstrated that dispensers loaded with 50 mg (a.i.) (20 g ha ―1 ) and 100 mg (a.i.) (40 g ha ―1 ) of sex pheromone were the most suitable, achieving significant reductions in male catches, compared to an untreated plot. In treated plots, virtually a 70% reduction in damage to fruit was recorded. Pheromone release profiles of all the dispensers were also studied under field conditions. We found that emission values > 250 μg day ―1 were the most suitable. This study suggests a new biodegradable dispenser capable of interfering with normal A. aurantii chemical communication. The use of mating disruption as a control method against A. aurantii is discussed.
G H Walter - One of the best experts on this subject based on the ideXlab platform.
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Mate Recognition in the South African Citrus Thrips Scirtothrips aurantii (Faure) and Cross-Mating Tests with Populations from Australia and South Africa
Journal of Insect Behavior, 2013Co-Authors: M. A. Rafter, G H WalterAbstract:South African citrus thrips ( Scirtothrips aurantii ) is a pest of citrus, mango and other horticultural species in its native range, which encompasses a large part of Africa. Its adventitious establishment in Australia in 2002 was a major cause for concern. The thrips, 11 years after its incursion into Australia, has remained on plants of a single host plant genus Bryophyllum (Crassulaceae). Characterization of the Specific-Mate Recognition System of the Bryophyllum population of thrips present in Australia and behavioral bioassay experiments revealed that compounds found in the insects’ body extracts play a crucial role in mate recognition of S . aurantii . Reciprocal cross-mating experiments between the Australian Bryophyllum insects and South African S . aurantii from horticultural host plants showed that mating frequencies were significantly lower in test crosses ( Bryophyllum x horticultural) than in controls ( Bryophyllum x Bryophyllum or horticultural x horticultural), which indicates there are at least two distinct species within S . aurantii and suggests further tests of this interpretation. The results suggest that these tiny phytophagous insects localize mates through their association with a particular host plant species (or closely-related group of species). Also, specific tests are suggested for clarifying the species status of the host-associated populations of S . aurantii in Africa.
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sampling of south african citrus thrips scirtothrips aurantii faure thysanoptera thripidae across host plant species in south africa
African Entomology, 2012Co-Authors: Michelle A Rafter, G H WalterAbstract:Scirtothrips aurantii Faure (Thysanoptera: Thripidae), the well-known economic pest of horticulture in Africa (Samways et al. 1987; Lewis 1997; Grove et al. 2000), established adventitiously in Australia around 2002. Although known colloquially as the South African citrus thrips, the species is a well-documented generalist that is reported from 70 to 100 plant species from 32 families (Gilbert 1989; de Villiers et al. 1987). Consequently, the establishment of this species in Australia was a major cause for concern (Anon. 2003), but no reports of S. aurantii attacking horticultural hosts in Australia have surfaced, despite several targeted surveys (Anon. 2003; Rafter et al. 2008).
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assessing the biological control potential of an adventitiously established pest scirtothrips aurantii faure on a weed bryophyllum delagoense eckl zeyh in queensland
Biological Control, 2011Co-Authors: Michelle A Rafter, William A Palmer, G H WalterAbstract:South African citrus thrips (Scirtothrips aurantii) established adventitiously in Australia. Although it is a major horticultural pest in Africa, it is now advocated as a possible biological control agent against Bryophyllum delagoense Eckl. & Zeyh. (Crassulaceae). To evaluate the biocontrol potential of S. aurantii a two year field study was conducted on the western Darling Downs of southern Queensland. Imidacloprid insecticide was applied to two quadrats at each of 18 field sites to assess, in the absence of S. aurantii, the persistence of individual plants and to quantify propagule production and recruitment by this declared weed. A third quadrat was left, as a control, to be infested naturally by S. aurantii. When released from herbivory by thrips in the field, plants grew significantly more, flowered more, and were significantly more fecund than plants in the quadrats with S. aurantii. Increases in growth and fecundity translated into significantly increased plant numbers but not increased recruitment. Recruitment even declined in experimental quadrats, through the indirect effects of releasing plants from herbivory. Field sampling also revealed that S. aurantii may be sensitive to seasonal climatic fluctuations. These and other local climatic influences may limit the biological control potential of the insect.
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assessing the biological control potential of an adventitiously established pest scirtothrips aurantii faure on a weed bryophyllum delagoense eckl zeyh in queensland
Biological Control, 2011Co-Authors: Michelle A Rafter, William A Palmer, G H WalterAbstract:South African citrus thrips (Scirtothrips aurantii) established adventitiously in Australia. Although it is a major horticultural pest in Africa, it is now advocated as a possible biological control agent against Bryophyllum delagoense Eckl. & Zeyh. (Crassulaceae). To evaluate the biocontrol potential of S. aurantii a two year field study was conducted on the western Darling Downs of southern Queensland. Imidacloprid insecticide was applied to two quadrats at each of 18 field sites to assess, in the absence of S. aurantii, the persistence of individual plants and to quantify propagule production and recruitment by this declared weed. A third quadrat was left, as a control, to be infested naturally by S. aurantii. When released from herbivory by thrips in the field, plants grew significantly more, flowered more, and were significantly more fecund than plants in the quadrats with S. aurantii. Increases in growth and fecundity translated into significantly increased plant numbers but not increased recruitment. Recruitment even declined in experimental quadrats, through the indirect effects of releasing plants from herbivory. Field sampling also revealed that S. aurantii may be sensitive to seasonal climatic fluctuations. These and other local climatic influences may limit the biological control potential of the insect.
Alberto Urbaneja - One of the best experts on this subject based on the ideXlab platform.
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contribution of predation to the biological control of a key herbivorous pest in citrus agroecosystems
Journal of Animal Ecology, 2019Co-Authors: Juan Pedro Raul Bouvet, Alberto Urbaneja, Meritxell Perezhedo, Cesar MonzoAbstract:Biological control has traditionally simplified the view of trophic relationships between herbivorous pests and their natural enemies in agriculture. The success or failure of this pest management strategy is still mainly attributed to the ability of a few key natural enemies to suppress the pest density. For example, successful regulation of the California red scale (Aonidiella aurantii), a key citrus pest, is generally credited to specific parasitoids of the Aphytis genus. Currently, research is revealing how herbivore regulation in agroecosystems can be alternatively achieved with a greater number of trophic associations within the system. The goals of the present study were as follows: i) to unravel species-specific trophic links between A. aurantii and its natural enemies in citrus agroecosystems, and ii) to assess their contribution to control of A. aurantii. Predation and parasitism of this herbivorous pest were assessed through exclusion experiments. Species-specific trophic links between this herbivorous pest and its natural enemies were studied using gut-content analysis of field-collected predators employing prey-specific DNA molecular markers. Relative predation rates of the species involved in A. aurantii regulation were estimated. Predation was found to be the main biotic component of A. aurantii mortality, causing reductions of more than 75% in recently settled cohorts. Aonidiella aurantii DNA was detected in the digestive system of 11 species of predators. Generalist and stenophagous predators, mainly associated with other citrus pests such as aphids, proved to be the most important biological control agents of this pest. Complex trophic relationships, such as apparent competition between two key citrus pests, were revealed. The present study highlights the role of predation as biotic mortality factor of key pests in perennial agroecosystems, wherein it is a rich complex of indigenous or naturalized generalist predators that are primarily responsible for this mortality. The results herein presented may therefore offer another perspective on the biological control of one of the key world-wide citrus pests, at least in those regions where specific parasitoids are not able to successfully regulate the scale populations.
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avances en el control biologico del piojo rojo de california en citricos por parasitoides del genero aphytis
Phytoma España. La revista profesional de sanidad vegetal, 2019Co-Authors: Ruth Cebolla, Alberto Urbaneja, Alejandro TenaAbstract:El piojo rojo de California, Aonidiella aurantii, se considera una de las plagas de los citricos mas importante a nivel mundial. Los principales enemigos naturales de A. aurantii son los parasitoides del genero Aphytis, los cuales ejercen un control biologico eficaz de esta plaga en la mayoria de regiones citricolas. Sin embargo, en los citricos espanoles, las especies presentes del genero Aphytis no ejercen un control biologico satisfactorio. En este trabajo se ha investigado la ecologia del comportamiento de estos parasitoides himenopteros con el fin de mejorar el control biologico de A. aurantii. En concreto, se ha analizado como afecta el cambio climatico y la competencia entre las dos especies de Aphytis presentes en la cuenca mediterranea al control biologico.
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mating disruption for the control of aonidiella aurantii maskell hemiptera diaspididae may contribute to increased effectiveness of natural enemies
Pest Management Science, 2012Co-Authors: Sandra Vacas, Pilar Vanaclocha, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: New directives on sustainable use of pesticides have encouraged research on efficient alternative pest control methods. In the case of the California red scale (CRS), Aonidiella aurantii (Maskell), this imperative, along with the many difficulties in controlling this pest, have led to the investigation of new approaches. Previously developed mating disruption (MD) dispensers, together with the augmentative releases of the parasitoid Aphytis melinus DeBach, are here considered as a combined strategy for use against A. aurantii. RESULTS: Efficacy of MD was demonstrated by a mean reduction of 80% in CRS male catches and a mean fruit damage reduction of 83% compared with the control. A delay in the development of A. aurantii instars was observed in the MD plot. This delay increased the period of exposure of the susceptible instars to natural enemies, which resulted in higher predation and parasitism levels in the MD plot. Under laboratory conditions, A. melinus mating behaviour and effects on A. aurantii were not significantly altered in a CRS-pheromone-saturated environment. CONCLUSION: Mating disruption pheromone did not affect the behaviour or level of parasitism by A. melinus or the incidence of other generalist predators. Therefore, A. aurantii pheromone appears to be compatible with augmentative releases and biological control, making its use a good strategy for CRS management. Copyright © 2011 Society of Chemical Industry
Michelle A Rafter - One of the best experts on this subject based on the ideXlab platform.
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Genotyping_S. aurantii
2016Co-Authors: Michelle A Rafter, James P. Hereward, Gimme H. WalterAbstract:Genotypes of screened Scirtothrips aurantii from 11 host associated populations across Australia and South Africa using eight microsatellite loci. Population/host plant codes: MBd (Miles, Bryophyllum delagoense), BBd (Brisbane, Bryophyllum delagoense), NBd (Nelspruit, Bryophyllum delagoense), NCs (Nelspruit, Citrus sinensis), NMi (Nelspruit, Macadamia integrifolia), NCp (Nelspruit, Caesalpinia pulcherrima), PCs (Pretoria, Citrus sinensis), PCm (Pretoria, Crassula multicava), PKb (Pretoria, Kalanchoe blossfeldiana), WCs (Western Cape, Citrus sinensis), WPg (Western Cape, Punica granatum). Contact: Dr Michelle Rafter - m.rafter@uq.edu.a
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sampling of south african citrus thrips scirtothrips aurantii faure thysanoptera thripidae across host plant species in south africa
African Entomology, 2012Co-Authors: Michelle A Rafter, G H WalterAbstract:Scirtothrips aurantii Faure (Thysanoptera: Thripidae), the well-known economic pest of horticulture in Africa (Samways et al. 1987; Lewis 1997; Grove et al. 2000), established adventitiously in Australia around 2002. Although known colloquially as the South African citrus thrips, the species is a well-documented generalist that is reported from 70 to 100 plant species from 32 families (Gilbert 1989; de Villiers et al. 1987). Consequently, the establishment of this species in Australia was a major cause for concern (Anon. 2003), but no reports of S. aurantii attacking horticultural hosts in Australia have surfaced, despite several targeted surveys (Anon. 2003; Rafter et al. 2008).
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assessing the biological control potential of an adventitiously established pest scirtothrips aurantii faure on a weed bryophyllum delagoense eckl zeyh in queensland
Biological Control, 2011Co-Authors: Michelle A Rafter, William A Palmer, G H WalterAbstract:South African citrus thrips (Scirtothrips aurantii) established adventitiously in Australia. Although it is a major horticultural pest in Africa, it is now advocated as a possible biological control agent against Bryophyllum delagoense Eckl. & Zeyh. (Crassulaceae). To evaluate the biocontrol potential of S. aurantii a two year field study was conducted on the western Darling Downs of southern Queensland. Imidacloprid insecticide was applied to two quadrats at each of 18 field sites to assess, in the absence of S. aurantii, the persistence of individual plants and to quantify propagule production and recruitment by this declared weed. A third quadrat was left, as a control, to be infested naturally by S. aurantii. When released from herbivory by thrips in the field, plants grew significantly more, flowered more, and were significantly more fecund than plants in the quadrats with S. aurantii. Increases in growth and fecundity translated into significantly increased plant numbers but not increased recruitment. Recruitment even declined in experimental quadrats, through the indirect effects of releasing plants from herbivory. Field sampling also revealed that S. aurantii may be sensitive to seasonal climatic fluctuations. These and other local climatic influences may limit the biological control potential of the insect.
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assessing the biological control potential of an adventitiously established pest scirtothrips aurantii faure on a weed bryophyllum delagoense eckl zeyh in queensland
Biological Control, 2011Co-Authors: Michelle A Rafter, William A Palmer, G H WalterAbstract:South African citrus thrips (Scirtothrips aurantii) established adventitiously in Australia. Although it is a major horticultural pest in Africa, it is now advocated as a possible biological control agent against Bryophyllum delagoense Eckl. & Zeyh. (Crassulaceae). To evaluate the biocontrol potential of S. aurantii a two year field study was conducted on the western Darling Downs of southern Queensland. Imidacloprid insecticide was applied to two quadrats at each of 18 field sites to assess, in the absence of S. aurantii, the persistence of individual plants and to quantify propagule production and recruitment by this declared weed. A third quadrat was left, as a control, to be infested naturally by S. aurantii. When released from herbivory by thrips in the field, plants grew significantly more, flowered more, and were significantly more fecund than plants in the quadrats with S. aurantii. Increases in growth and fecundity translated into significantly increased plant numbers but not increased recruitment. Recruitment even declined in experimental quadrats, through the indirect effects of releasing plants from herbivory. Field sampling also revealed that S. aurantii may be sensitive to seasonal climatic fluctuations. These and other local climatic influences may limit the biological control potential of the insect.
Pilar Vanaclocha - One of the best experts on this subject based on the ideXlab platform.
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mating disruption for the control of aonidiella aurantii maskell hemiptera diaspididae may contribute to increased effectiveness of natural enemies
Pest Management Science, 2012Co-Authors: Sandra Vacas, Pilar Vanaclocha, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: New directives on sustainable use of pesticides have encouraged research on efficient alternative pest control methods. In the case of the California red scale (CRS), Aonidiella aurantii (Maskell), this imperative, along with the many difficulties in controlling this pest, have led to the investigation of new approaches. Previously developed mating disruption (MD) dispensers, together with the augmentative releases of the parasitoid Aphytis melinus DeBach, are here considered as a combined strategy for use against A. aurantii. RESULTS: Efficacy of MD was demonstrated by a mean reduction of 80% in CRS male catches and a mean fruit damage reduction of 83% compared with the control. A delay in the development of A. aurantii instars was observed in the MD plot. This delay increased the period of exposure of the susceptible instars to natural enemies, which resulted in higher predation and parasitism levels in the MD plot. Under laboratory conditions, A. melinus mating behaviour and effects on A. aurantii were not significantly altered in a CRS-pheromone-saturated environment. CONCLUSION: Mating disruption pheromone did not affect the behaviour or level of parasitism by A. melinus or the incidence of other generalist predators. Therefore, A. aurantii pheromone appears to be compatible with augmentative releases and biological control, making its use a good strategy for CRS management. Copyright © 2011 Society of Chemical Industry
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evaluacion de distintas estrategias de manejo quimico del piojo rojo de california aonidiella aurantii maskell
Levante Agrícola (0457-6039) no. 404 (1er trim. 2011) pp. 44-48, 2011Co-Authors: Jose Catalan, Pilar Vanaclocha, Josep A Jaques, Pablo UrbanejaAbstract:RESUMEN El piojo rojo de California, Aonidiella aurantii , es una plaga clave en el cul-tivo de los citricos. Por lo general, esta plaga se combate realizando unaaplicacion fitosanitaria en primera generacion y, si es necesario, otra ensegunda generacion alternando los insecticidas clorpirifos y piriproxifen. Eneste trabajo se han evaluado diversas estrategias de control basadas en lautilizacion de dos insecticidas, piriproxifen y spirotetramat, aplicados en dosepocas distintas, salida del invierno y primera generacion de A. aurantii. Eltrabajo se ha realizado en un campo de citricos con un elevado nivel deinfestacion de A. aurantiien la cosecha anterior. Ambos insecticidas alcan-zaron eficacias elevadas en cosecha, tanto cuando se aplicaron en primerageneracion, como a la salida del invierno. El porcentaje de destrio se redu-jo hasta un 100 % con spirotetramat y 86 % con piriproxifen en primera gene-racion respecto al ano anterior. Por otro lado, las aplicaciones a la salida delinvierno tambien resultaron eficaces y redujeron el porcentaje de destrio enmas de un 66 %. Ademas, la eficacia de spirotetramat aplicado en inviernoredujo el numero medio de escudos por fruto en un 80 %. Por lo tanto, lostratamientos en invierno aparecen como una alternativa interesante en lagestion de A. aurantiiporque ademas de reducir significativamente suspoblaciones, pueden tener menores efectos secundarios sobre la fauna utiltan abundante y beneficiosa en nuestros citricos.
