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Sandra Vacas - One of the best experts on this subject based on the ideXlab platform.
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Effect of the California red scale Aonidiella aurantii sex pheromone on the natural parasitism by Aphytis spp. in Mediterranean citrus
Biological Control, 2015Co-Authors: Apostolos Pekas, Ferran Garcia-marí, Jaime Primo, Vicente Navarro-llopis, Sandra VacasAbstract:Abstract Mating disruption has proved successful against California red scale (CRS), Aonidiella aurantii Maskell (Hemiptera: Diaspididae) in Mediterranean citrus. Although mating disruption does not affect negatively the parasitism by Aphytis melinus DeBach (Hymenoptera: Aphelinidae), a CRS parasitoid introduced to the Mediterranean, there is no information regarding its potential effect on the native Aphytis species. In the present study, the effect of CRS mating disruption on the field parasitism inflicted by Aphytis spp. has been assessed and compared to a mineral oil and a control treatment. In order to confirm the effectiveness of the mating disruption we also evaluated its effect on the captures of the CRS males and on fruit infestation. Moreover, the potential role of the CRS sex pheromone as kairomone for the Aphytis species was also evaluated by comparing captures of parasitoids on sticky traps with or without pheromone. Significantly lower CRS male captures and fruit damage were registered in the mating disruption respect to the control or oil treatments indicating that mating disruption was effective. In September, when compared to the control, parasitism by Aphytis spp. was significantly lower in the mating disruption and mineral oil treatments and crucially no Aphytis chrysomphali Mercet were registered in the mating disruption treatment. Finally, while the captures of both A. melinus and Aphytis lepidosaphes (Mercet) were not significantly different between traps with or without pheromone, A. chrysomphali captures were significantly higher in traps baited with CRS pheromone. These results suggest a possible kairomonal effect of the CRS pheromone on A. chrysomphali .
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Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus
Journal of Pest Science, 2014Co-Authors: Sandra Vacas, Cristina Alfaro, Jaime Primo, Vicente Navarro-llopisAbstract:The rejection of citrus fruit caused by infestations of the California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), raises concerns about its management. This fact has led to the introduction of new integrated control methods in citrus orchards, including the implementation of techniques based on pheromones. Previous works described efficient mating disruption pheromone dispensers to control A. aurantii in the Mediterranean region. The main aims of the present study were to adjust the timing of dispenser applications and study the importance of controlling the early first generation of A. aurantii by testing two different application dates: before and after the first CRS male flight. The efficacy of the different mating disruption strategies was tested during 2010 in an experimental orchard and these results were confirmed during 2011 in a commercial citrus farm. Results showed that every mating disruption strategy achieved significantly lower male captures in monitoring pheromone traps compared with untreated plots, as well as mean fruit infestation reductions of about 80 %. The control of the first CRS generation is not essential for achieving a good efficacy as demonstrated in two locations with different pest pressure. The late application of MD dispensers before the second CRS male flight has proven to be effective, suggesting a new advantageous way to apply mating disruption.
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life history parameters and scale cover surface area of Aonidiella aurantii are altered in a mating disruption environment implications for biological control
Pest Management Science, 2012Co-Authors: Pilar Vanaclocha, Sandra Vacas, Cristina Alfaro, Vicente Navarrollopis, Jaime Primo, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry
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Life history parameters and scale‐cover surface area of Aonidiella aurantii are altered in a mating disruption environment: implications for biological control
Pest management science, 2012Co-Authors: Pilar Vanaclocha, Sandra Vacas, Cristina Alfaro, Jaime Primo, Vicente Navarro-llopis, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry
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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, Alberto Urbaneja, Cristina Alfaro, Jaime Primo, Maria Jesús Verdú, Vicente NavarrollopisAbstract: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
Jaime Primo - One of the best experts on this subject based on the ideXlab platform.
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Effect of the California red scale Aonidiella aurantii sex pheromone on the natural parasitism by Aphytis spp. in Mediterranean citrus
Biological Control, 2015Co-Authors: Apostolos Pekas, Ferran Garcia-marí, Jaime Primo, Vicente Navarro-llopis, Sandra VacasAbstract:Abstract Mating disruption has proved successful against California red scale (CRS), Aonidiella aurantii Maskell (Hemiptera: Diaspididae) in Mediterranean citrus. Although mating disruption does not affect negatively the parasitism by Aphytis melinus DeBach (Hymenoptera: Aphelinidae), a CRS parasitoid introduced to the Mediterranean, there is no information regarding its potential effect on the native Aphytis species. In the present study, the effect of CRS mating disruption on the field parasitism inflicted by Aphytis spp. has been assessed and compared to a mineral oil and a control treatment. In order to confirm the effectiveness of the mating disruption we also evaluated its effect on the captures of the CRS males and on fruit infestation. Moreover, the potential role of the CRS sex pheromone as kairomone for the Aphytis species was also evaluated by comparing captures of parasitoids on sticky traps with or without pheromone. Significantly lower CRS male captures and fruit damage were registered in the mating disruption respect to the control or oil treatments indicating that mating disruption was effective. In September, when compared to the control, parasitism by Aphytis spp. was significantly lower in the mating disruption and mineral oil treatments and crucially no Aphytis chrysomphali Mercet were registered in the mating disruption treatment. Finally, while the captures of both A. melinus and Aphytis lepidosaphes (Mercet) were not significantly different between traps with or without pheromone, A. chrysomphali captures were significantly higher in traps baited with CRS pheromone. These results suggest a possible kairomonal effect of the CRS pheromone on A. chrysomphali .
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Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus
Journal of Pest Science, 2014Co-Authors: Sandra Vacas, Cristina Alfaro, Jaime Primo, Vicente Navarro-llopisAbstract:The rejection of citrus fruit caused by infestations of the California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), raises concerns about its management. This fact has led to the introduction of new integrated control methods in citrus orchards, including the implementation of techniques based on pheromones. Previous works described efficient mating disruption pheromone dispensers to control A. aurantii in the Mediterranean region. The main aims of the present study were to adjust the timing of dispenser applications and study the importance of controlling the early first generation of A. aurantii by testing two different application dates: before and after the first CRS male flight. The efficacy of the different mating disruption strategies was tested during 2010 in an experimental orchard and these results were confirmed during 2011 in a commercial citrus farm. Results showed that every mating disruption strategy achieved significantly lower male captures in monitoring pheromone traps compared with untreated plots, as well as mean fruit infestation reductions of about 80 %. The control of the first CRS generation is not essential for achieving a good efficacy as demonstrated in two locations with different pest pressure. The late application of MD dispensers before the second CRS male flight has proven to be effective, suggesting a new advantageous way to apply mating disruption.
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life history parameters and scale cover surface area of Aonidiella aurantii are altered in a mating disruption environment implications for biological control
Pest Management Science, 2012Co-Authors: Pilar Vanaclocha, Sandra Vacas, Cristina Alfaro, Vicente Navarrollopis, Jaime Primo, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry
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Life history parameters and scale‐cover surface area of Aonidiella aurantii are altered in a mating disruption environment: implications for biological control
Pest management science, 2012Co-Authors: Pilar Vanaclocha, Sandra Vacas, Cristina Alfaro, Jaime Primo, Vicente Navarro-llopis, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry
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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, Alberto Urbaneja, Cristina Alfaro, Jaime Primo, Maria Jesús Verdú, Vicente NavarrollopisAbstract: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
Patricia Chueca - One of the best experts on this subject based on the ideXlab platform.
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efficacy of standard and low drift nozzles for insecticide applications against Aonidiella aurantii maskell in citrus
Julius-Kühn-Archiv, 2015Co-Authors: Cruz Garcera, Eduardo Moltó, R Abad, J A Insa, Xavier Torrent, C Roman, S Planas, Patricia ChuecaAbstract:Efficacy of standard and low drift nozzles for insecticide applications against Aonidiella aurantii (Maskell) in citrus C. Garcera 1, E. Molto 1, R. Abad2, J.A. Insa2, X. Torrent3, C. Roman3, S. Planas3, P. Chueca1 1 Instituto Valenciano de Investigaciones Agrarias. Centro de Agroingenieria. Moncada, Valencia, SPAIN 2 Dow Agrosciences Iberica S.A. Madrid SPAIN Universitat de Lleida. Dep. Agroforestry Eng.Agrotecnio. Lleida SPAIN.
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Factors influencing the efficacy of two organophosphate insecticides in controlling California red scale, Aonidiella aurantii (Maskell). A basis for reducing spray application volume in Mediterranean conditions
Pest Management Science, 2014Co-Authors: Cruz Garcera, Eduardo Moltó, Patricia ChuecaAbstract:BackgroundBecause society is seeking ways to lessen the environmental impact of agricultural activity, dose adjustment has become a key issue in current plant protection treatments with high spray application volumes, such as on citrus plants. This work investigates, in field conditions, the factors affecting the efficacy of organophosphate insecticides against California red scale (CRS), Aonidiella aurantii (Maskell), when the delivery rate is decreased. Insecticide rate changes were induced by modifying the spray application volumes of two commercial organophosphate pesticides based on chlorpyrifos and chlorpyrifos-methyl. ResultsResults showed that, with increase in the spray volume, the coverage and the uniformity of deposition on the canopy increased, but final infestation depended neither on the spray application volume nor on the coverage. Furthermore, final infestation significantly depended on the pest pressure in the plot and the spray volume applied per unit volume of canopy (L m(-3) canopy). Moreover, it was found that the final infestation was influenced by the efficiency of deposition in the applications that were carried out against the second-generation of CRS. ConclusionBecause the spray application volume did not affect the final infestation, this research introduces the possibility that reducing the doses of current citrus organophosphate treatments may still allow effective plant protection in Mediterranean conditions. (c) 2013 Society of Chemical Industry
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Modelling the spray deposition and efficacy of two mineral oil-based products for the control of California red scale, Aonidiella aurantii (Maskell)
Crop Protection, 2012Co-Authors: Cruz Garcera, Eduardo Moltó, Manuel Zarzo, Patricia ChuecaAbstract:Abstract The pattern and quantity of pesticide deposition may affect the efficacy of pesticide treatments. In this study we evaluated under laboratory conditions the efficacy of two petroleum-derived spray oils (PDSO) (Laincoil ® , an n C21 oil with a content of 83% w/v, Oil A, and Sunspray Ultrafine ® , an n C21 with a content of 85% w/v, Oil B, both with an unsulfonated residue of 92%) applied at 1.5% concentration at five volumes (0.5, 1, 2, 3 and 4 ml) against different stages of Aonidiella aurantii Maskell (Homoptera: Diaspididae). In parallel, we characterized the deposition pattern of treatments resulting from these five volumes and two PDSOs. The objective was to model deposition characteristics and efficacy as a function of the deposited volume in order to determine the optimum volume per unit surface that should be applied to control this pest. Different models that depend on the developmental stage and relate to the efficacy of the treatment as a function of the deposited volume have been obtained for both PDSOs, thus providing a scientific basis for product efficacy comparison. Furthermore, our results are also relevant to find an adequate trade-off between sprayed pesticide volume and expected efficacy.
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effect of spray volume of two organophosphate pesticides on coverage and on mortality of california red scale Aonidiella aurantii maskell
Crop Protection, 2011Co-Authors: Cruz Garcera, Eduardo Moltó, Patricia ChuecaAbstract:Abstract A trial under laboratory conditions was carried out to study the possibility of decreasing the delivered dose of organophosphate insecticides without affecting their efficacy against California red scale (CRS), Aonidiella aurantii (Maskell), by reducing the volume of water used whilst maintaining the concentration of pesticide. In order to establish an optimal application volume, the coverage and the efficacy against different stages of development of CRS of two commercial organophosphate pesticides (chlorpyrifos 750 g kg−1 WG [Dursban® 75 WG] and chlorpyrifos-methyl 224 g l−1 EC [Reldan® E]) at four volumes of water (1, 2, 3 and 4 ml) were compared. Results showed that in general Chlorpyrifos-methyl-based product (CMBP) provided greater coverage and impact size, but did not achieve the highest efficacy. The minimum-deposited volume (1.01 μl/cm2) produced 11% coverage with Chlorpyrifos-based product (CBP) and 22% with CMBP, reaching the highest efficacies (around 89–95%) against the youngest stages (N1 and N2 stages) with both products. To attain similar efficacy with males (prepupal and pupa stages), twice the volume (2.03 μl/cm2) of the CBP was required, producing 28% coverage. The CMBP required higher deposited volumes (3.41 μl/cm2) and higher coverage (51%). The maximum efficacy in the control of adult females (third instar and gravid female stages) was 70% with both pesticides. This level was attained with 3.41 μl/cm2 of CBP (36% coverage) and 4.72 μl/cm2 of CMBP (62% coverage). The research shows that greater coverage does not result in greater efficacy, so it would be possible to reduce the spray volume in field conditions. Further research will be carried out in order to check these results under real field conditions.
Cristina Alfaro - One of the best experts on this subject based on the ideXlab platform.
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Deployment of mating disruption dispensers before and after first seasonal male flights for the control of Aonidiella aurantii in citrus
Journal of Pest Science, 2014Co-Authors: Sandra Vacas, Cristina Alfaro, Jaime Primo, Vicente Navarro-llopisAbstract:The rejection of citrus fruit caused by infestations of the California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), raises concerns about its management. This fact has led to the introduction of new integrated control methods in citrus orchards, including the implementation of techniques based on pheromones. Previous works described efficient mating disruption pheromone dispensers to control A. aurantii in the Mediterranean region. The main aims of the present study were to adjust the timing of dispenser applications and study the importance of controlling the early first generation of A. aurantii by testing two different application dates: before and after the first CRS male flight. The efficacy of the different mating disruption strategies was tested during 2010 in an experimental orchard and these results were confirmed during 2011 in a commercial citrus farm. Results showed that every mating disruption strategy achieved significantly lower male captures in monitoring pheromone traps compared with untreated plots, as well as mean fruit infestation reductions of about 80 %. The control of the first CRS generation is not essential for achieving a good efficacy as demonstrated in two locations with different pest pressure. The late application of MD dispensers before the second CRS male flight has proven to be effective, suggesting a new advantageous way to apply mating disruption.
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life history parameters and scale cover surface area of Aonidiella aurantii are altered in a mating disruption environment implications for biological control
Pest Management Science, 2012Co-Authors: Pilar Vanaclocha, Sandra Vacas, Cristina Alfaro, Vicente Navarrollopis, Jaime Primo, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry
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Life history parameters and scale‐cover surface area of Aonidiella aurantii are altered in a mating disruption environment: implications for biological control
Pest management science, 2012Co-Authors: Pilar Vanaclocha, Sandra Vacas, Cristina Alfaro, Jaime Primo, Vicente Navarro-llopis, Maria Jesús Verdú, Alberto UrbanejaAbstract:BACKGROUND: In recent years, environmentally safe measures to control the California red scale (CRS), Aonidiella aurantii (Maskell), have been successfully implemented. These measures include mating disruption (MD) and biological control. The goal of this study was to examine the effect of high concentrations of the CRS sex pheromone on its life history parameters and scale-cover surface area under controlled laboratory conditions. RESULTS: The developmental time of both males and females of CRS increased with exposure to airborne pheromone. MD had an effect on both the total number of progeny and on the crawler production period for females. Accordingly, demographic parameters such as net fecundity (R0) and intrinsic rate of increase (rm) were significantly lower in the pheromone-treated populations. The largest scale-cover surface areas were observed in the CRS reared in the pheromone environment. CONCLUSION: A clear influence of airborne pheromone on the biology of CRS has been demonstrated. In addition to the classical mating disruption benefits of this technique, additional benefits, such as increase in the duration of exposure to natural enemies and increase in size, which benefits some species of parasitoids, have been confirmed. Copyright © 2012 Society of Chemical Industry
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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, Alberto Urbaneja, Cristina Alfaro, Jaime Primo, Maria Jesús Verdú, Vicente NavarrollopisAbstract: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
Cruz Garcera - One of the best experts on this subject based on the ideXlab platform.
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efficacy of standard and low drift nozzles for insecticide applications against Aonidiella aurantii maskell in citrus
Julius-Kühn-Archiv, 2015Co-Authors: Cruz Garcera, Eduardo Moltó, R Abad, J A Insa, Xavier Torrent, C Roman, S Planas, Patricia ChuecaAbstract:Efficacy of standard and low drift nozzles for insecticide applications against Aonidiella aurantii (Maskell) in citrus C. Garcera 1, E. Molto 1, R. Abad2, J.A. Insa2, X. Torrent3, C. Roman3, S. Planas3, P. Chueca1 1 Instituto Valenciano de Investigaciones Agrarias. Centro de Agroingenieria. Moncada, Valencia, SPAIN 2 Dow Agrosciences Iberica S.A. Madrid SPAIN Universitat de Lleida. Dep. Agroforestry Eng.Agrotecnio. Lleida SPAIN.
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Factors influencing the efficacy of two organophosphate insecticides in controlling California red scale, Aonidiella aurantii (Maskell). A basis for reducing spray application volume in Mediterranean conditions
Pest Management Science, 2014Co-Authors: Cruz Garcera, Eduardo Moltó, Patricia ChuecaAbstract:BackgroundBecause society is seeking ways to lessen the environmental impact of agricultural activity, dose adjustment has become a key issue in current plant protection treatments with high spray application volumes, such as on citrus plants. This work investigates, in field conditions, the factors affecting the efficacy of organophosphate insecticides against California red scale (CRS), Aonidiella aurantii (Maskell), when the delivery rate is decreased. Insecticide rate changes were induced by modifying the spray application volumes of two commercial organophosphate pesticides based on chlorpyrifos and chlorpyrifos-methyl. ResultsResults showed that, with increase in the spray volume, the coverage and the uniformity of deposition on the canopy increased, but final infestation depended neither on the spray application volume nor on the coverage. Furthermore, final infestation significantly depended on the pest pressure in the plot and the spray volume applied per unit volume of canopy (L m(-3) canopy). Moreover, it was found that the final infestation was influenced by the efficiency of deposition in the applications that were carried out against the second-generation of CRS. ConclusionBecause the spray application volume did not affect the final infestation, this research introduces the possibility that reducing the doses of current citrus organophosphate treatments may still allow effective plant protection in Mediterranean conditions. (c) 2013 Society of Chemical Industry
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effects of spirotetramat on Aonidiella aurantii homoptera diaspididae and its parasitoid aphytis melinus hymenoptera aphelinidae
Journal of Economic Entomology, 2013Co-Authors: Cruz Garcera, Eduardo Moltó, Yuling Ouyang, Sara J Scott, Elizabeth E GraftoncardwellAbstract:ABSTRACT Laboratory and field studies were conducted to measure the effects of spirotetramat on life stages of California red scale, Aonidiella aurantii (Maskell), and a primary parasitoid, Aphytis melinus DeBach. Organophosphate-resistant and -susceptible populations responded similarly to spirotetramat, suggesting there is no cross-resistance between these insecticide classes. First and second instar male and female A. aurantii were 10- and 32-fold more susceptible to spirotetramat (LC50 = 0.1–0.2 ppm) compared with early third (LC50 = 1.5 ppm) and late third instar females (LC50 = 5.3 ppm). The LC99 value indicated that late stage third instar females would not be fully controlled by a field rate of spirotetramat; however, spirotetramat would reduce their fecundity by 89%. Field applications of spirotetramat in two water volumes and using two adjuvants (oil and a nonionic spray adjuvant) showed similar reduction in A. aurantii numbers, even though the higher water volume demonstrated more complete cove...
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Modelling the spray deposition and efficacy of two mineral oil-based products for the control of California red scale, Aonidiella aurantii (Maskell)
Crop Protection, 2012Co-Authors: Cruz Garcera, Eduardo Moltó, Manuel Zarzo, Patricia ChuecaAbstract:Abstract The pattern and quantity of pesticide deposition may affect the efficacy of pesticide treatments. In this study we evaluated under laboratory conditions the efficacy of two petroleum-derived spray oils (PDSO) (Laincoil ® , an n C21 oil with a content of 83% w/v, Oil A, and Sunspray Ultrafine ® , an n C21 with a content of 85% w/v, Oil B, both with an unsulfonated residue of 92%) applied at 1.5% concentration at five volumes (0.5, 1, 2, 3 and 4 ml) against different stages of Aonidiella aurantii Maskell (Homoptera: Diaspididae). In parallel, we characterized the deposition pattern of treatments resulting from these five volumes and two PDSOs. The objective was to model deposition characteristics and efficacy as a function of the deposited volume in order to determine the optimum volume per unit surface that should be applied to control this pest. Different models that depend on the developmental stage and relate to the efficacy of the treatment as a function of the deposited volume have been obtained for both PDSOs, thus providing a scientific basis for product efficacy comparison. Furthermore, our results are also relevant to find an adequate trade-off between sprayed pesticide volume and expected efficacy.
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effect of spray volume of two organophosphate pesticides on coverage and on mortality of california red scale Aonidiella aurantii maskell
Crop Protection, 2011Co-Authors: Cruz Garcera, Eduardo Moltó, Patricia ChuecaAbstract:Abstract A trial under laboratory conditions was carried out to study the possibility of decreasing the delivered dose of organophosphate insecticides without affecting their efficacy against California red scale (CRS), Aonidiella aurantii (Maskell), by reducing the volume of water used whilst maintaining the concentration of pesticide. In order to establish an optimal application volume, the coverage and the efficacy against different stages of development of CRS of two commercial organophosphate pesticides (chlorpyrifos 750 g kg−1 WG [Dursban® 75 WG] and chlorpyrifos-methyl 224 g l−1 EC [Reldan® E]) at four volumes of water (1, 2, 3 and 4 ml) were compared. Results showed that in general Chlorpyrifos-methyl-based product (CMBP) provided greater coverage and impact size, but did not achieve the highest efficacy. The minimum-deposited volume (1.01 μl/cm2) produced 11% coverage with Chlorpyrifos-based product (CBP) and 22% with CMBP, reaching the highest efficacies (around 89–95%) against the youngest stages (N1 and N2 stages) with both products. To attain similar efficacy with males (prepupal and pupa stages), twice the volume (2.03 μl/cm2) of the CBP was required, producing 28% coverage. The CMBP required higher deposited volumes (3.41 μl/cm2) and higher coverage (51%). The maximum efficacy in the control of adult females (third instar and gravid female stages) was 70% with both pesticides. This level was attained with 3.41 μl/cm2 of CBP (36% coverage) and 4.72 μl/cm2 of CMBP (62% coverage). The research shows that greater coverage does not result in greater efficacy, so it would be possible to reduce the spray volume in field conditions. Further research will be carried out in order to check these results under real field conditions.
