Successful integrated pest management in protected crops implies an evalu-ation of the compatibility of pesticides and natural enemies(NE),as control strategies that only rely on one tactic can fail when pest populati...Successful integrated pest management in protected crops implies an evalu-ation of the compatibility of pesticides and natural enemies(NE),as control strategies that only rely on one tactic can fail when pest populations exceed NE activity or pests become resistant to pesticides.Nowadays in Almeria(Spain),growers release NE prior to transplanting or early in the crop cycle to favor their settlement before pest arrival because this improves biocontrol efficacy,although it extends pesticide exposure periods.The pur-pose of this research was to evaluate the compatibility of two applications of pesticides with key NE in 2-year trials inside tomato and sweet pepper commercial greenhouses:Nesidiocoris tenuis(Reuter)(Hemiptera:Miridae),Orius laevigatus(Say)(Hemiptera:Anthocoridae)and Amblyseius swirskii(Athias-Henriot)(Acari:Phytoseidac).In tomato,flubendiamide and chlorantraniliprole(IOBC category 1)were compatible with N.tenuis,but chlorpyrifos.:methyl and spinosad(IOBC categories 2-3),which efectively reduced Tiuta absoluta(Meyrick)(Lepidoptera:Gelechidae)density,compromised its predatory activity.In sweet pepper,chlorantraniliprole(IOBC category 1)was the only pesticide compatible with O.laevigatus while chlorantraniliprole,emamectin benzoate,spirote-tramat and pymetrozine were harmless(IOBC category 1)to Amblyseius swirskii,and sulfoxaflor slightly harmful(IOBC category 2)to this phytoseiid predator.展开更多
Zoophytophagous mirid species,that feed and develop either on prey or plant resources,are often found simultaneously on the same host.Hence,these species can engage in both intraguild predation and cannibalism,which c...Zoophytophagous mirid species,that feed and develop either on prey or plant resources,are often found simultaneously on the same host.Hence,these species can engage in both intraguild predation and cannibalism,which can pose a threat to mirid eggs.Ovipositing females may respond to such risks of predation on their eggs by reducing the number of eggs laid or selecting safer oviposition sites.We tested the oviposition behavior of Macrolophus pygmaeus(Rambur)(Hemiptera:Miridae)females under the risk of cannibalism by M.pygmaeus males and intraguild predation by Nesidiocoris tenuis(Reuter)males(Hemiptera:Miridae)under laboratory conditions.Intraguild predators and cannibals were introduced during or after the oviposition period.The number of eggs laid(using counts of newly hatched nymphs)and their proportion on each part of a tomato plant were both measured.The results reveal that only cannibalism by M.pygmaeus males after the period of oviposition significantly decreased the number of hatched eggs.Cannibalism thus represents a greater risk to mirid eggs than intraguild predation.The M.pygmaeus female responded to the presence of potential intraguild predators(or competitors)by decreasing the nu mber of eggs laid in the upper leaves.The results suggest that M.pygmaeus females avoid competition by N.tenuis,by laying fewer eggs on upper leaves.Cannibalism could regulate zoophytophagous predator populations under prey scarcity conditions and minimize the risk of crop damage associated with those biological control agents.展开更多
基金This research was funded by Spanish Ministry of Sci-ence,Innovation and Universities projects AGL2013-47603-C2-1-R and AGL2017-83498-C2-2-R awarded to Elisa Viuela and Pilar Medina,along with post-doctoral fellowships awarded to Beatriz Dader(Span-ish Ministry of Science,Innovation and Universities FJCI-2016-28443 and Universidad Politecnica de Madrid PINV18XFWLGK24S2US6D).We deeply appreciate the cooperation of two farmers that allowed us to perform tri-als in their commercial greenhouses.We are indebted to Dr.Christina Elizabeth Pease for English revision and to Dr.Ismael Sanchez from INIA for help with statistics.
文摘Successful integrated pest management in protected crops implies an evalu-ation of the compatibility of pesticides and natural enemies(NE),as control strategies that only rely on one tactic can fail when pest populations exceed NE activity or pests become resistant to pesticides.Nowadays in Almeria(Spain),growers release NE prior to transplanting or early in the crop cycle to favor their settlement before pest arrival because this improves biocontrol efficacy,although it extends pesticide exposure periods.The pur-pose of this research was to evaluate the compatibility of two applications of pesticides with key NE in 2-year trials inside tomato and sweet pepper commercial greenhouses:Nesidiocoris tenuis(Reuter)(Hemiptera:Miridae),Orius laevigatus(Say)(Hemiptera:Anthocoridae)and Amblyseius swirskii(Athias-Henriot)(Acari:Phytoseidac).In tomato,flubendiamide and chlorantraniliprole(IOBC category 1)were compatible with N.tenuis,but chlorpyrifos.:methyl and spinosad(IOBC categories 2-3),which efectively reduced Tiuta absoluta(Meyrick)(Lepidoptera:Gelechidae)density,compromised its predatory activity.In sweet pepper,chlorantraniliprole(IOBC category 1)was the only pesticide compatible with O.laevigatus while chlorantraniliprole,emamectin benzoate,spirote-tramat and pymetrozine were harmless(IOBC category 1)to Amblyseius swirskii,and sulfoxaflor slightly harmful(IOBC category 2)to this phytoseiid predator.
基金the Spanish Ministry of Economy and Competitiveness(Project AGL2011-24349)the CERCA Programme of the Generalitat de Catalunya.
文摘Zoophytophagous mirid species,that feed and develop either on prey or plant resources,are often found simultaneously on the same host.Hence,these species can engage in both intraguild predation and cannibalism,which can pose a threat to mirid eggs.Ovipositing females may respond to such risks of predation on their eggs by reducing the number of eggs laid or selecting safer oviposition sites.We tested the oviposition behavior of Macrolophus pygmaeus(Rambur)(Hemiptera:Miridae)females under the risk of cannibalism by M.pygmaeus males and intraguild predation by Nesidiocoris tenuis(Reuter)males(Hemiptera:Miridae)under laboratory conditions.Intraguild predators and cannibals were introduced during or after the oviposition period.The number of eggs laid(using counts of newly hatched nymphs)and their proportion on each part of a tomato plant were both measured.The results reveal that only cannibalism by M.pygmaeus males after the period of oviposition significantly decreased the number of hatched eggs.Cannibalism thus represents a greater risk to mirid eggs than intraguild predation.The M.pygmaeus female responded to the presence of potential intraguild predators(or competitors)by decreasing the nu mber of eggs laid in the upper leaves.The results suggest that M.pygmaeus females avoid competition by N.tenuis,by laying fewer eggs on upper leaves.Cannibalism could regulate zoophytophagous predator populations under prey scarcity conditions and minimize the risk of crop damage associated with those biological control agents.
