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An. Soc. Entomol. Brasil 29(2): 309-317 (2000) Functional Response of Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae)Fed on Schizaphis graminum (Rondani) (Hemiptera: Aphididae)ABSTRACT -The functional response of Chrysoperla externa (Hagen) fed on Schizaphis graminum (Rondani) was studied under five densities of prey. The experimental design was completely randomized with five treatments and ten replications. The tests were conducted in growth chambers at 25 ± 1ºC, RH of 70 ± 10% and photophase of 12 hours. Consumption increased in function of prey density in all instars. However, consumption tended to stabilize when a pre established average density of prey was offered, except for the first instar, which showed a constant increase in aphid consumption. The duration of the first and third instars and of the larval phase, as a whole, increased in function of the increased availability of prey. The duration of the second instar, however, decreased in function of increased prey availability. The results for the 1st, 2nd and 3rd instars and the larval phase showed a Type II functional response. Handling and searching time was evaluated for the average density of offered prey. The lowest searching time was verified for second instar larvae while the first instar showed the highest searching and handling time. Handling time diminished progressively with larvae development.

Adequação do Pólen de Leguminosas Utilizadas em Adubação Verde como Fonte de Alimento paraChrysoperla externa (Hagen) (Neuroptera: Chrysopidae) RESUMO ABSTRACT -Diversification of crops with species that provide suitable pollen for predators may reduce pest population on crops by enhancing predator effectiveness. In this paper we evaluated the suitability of leguminous cover crop pollens to the predatory green lacewing Chrysoperla externa (Hagen). The predator is commonly found in coffee agroecosystems and the plant species tested were pigeon pea and sunn hemp, which are used in organic coffee systems. Newly emerged females and males of C. externa were reared on diets containing pollen of pigeon pea, sunn hemp, or castor bean, used as a control. The reproductive success of C. externa was evaluated when females fed the pollen species and when honey was added to the diets, to verify the predator need for an extra carbohydrate source. Similar intrinsic growth rates were found for females fed on pigeon pea pollen and on sunn hemp pollen but these rates increased significantly when honey was added to the diets. Females fed with pigeon pea pollen plus honey and with sunn hemp pollen plus honey had higher intrinsic growth rates than those fed with castor bean pollen plus honey. Females fed on castor bean pollen only or on honey only, did not oviposit. Leguminous pollen species were equally suitable for C. externa especially when they were complemented with honey. The results suggest that to successfully enhance predator effectiveness, organic coffee plantation should be diversified with plant providing pollen in combination with plant providing nectar.

-The objective of this work was to evaluate the effect the insecticides endosulfan (1.05 g a.i./L), esfenvalerate (0.075 g a.i./L), fenpropathrin (0.09 g a.i./L), trichlorfon (0.09 g a.i./L) and triflumuron (0.0375 g a.i./L), used to control Alabama argillacea (Hübner), on eggs and larvae of Chrysoperla externa (Hagen), under greenhouse conditions. Egg viability, duration of the embryonic period and survival of first-instar larvae ecloded from treated eggs were evaluated. For first, second and third-instar larvae treated with the insecticides, subsequent survival of the larvae and pupae, as well as viability of the eggs produced by the emerged adults, were evaluated. The insecticides esfenvalerate and triflumuron caused a significant increase in the embryonic period of C. externa. Endosulfan, fenpropathrin, trichlorfon and triflumuron were highly toxic to larvae, with mortality rates ranging from 71% to 100%. Esfenvalerate caused only about 20% mortality of the first-and thirdinstar larvae and 38% of the second-instar larvae. Besides causing low larval mortality, esfenvalerate did not affect pupae survival or the reproductive capacity of the adults in the studied period, thus showing good potential for use in integrated pest management in cotton crops. Avaliou-se a viabilidade dos ovos, o período embrionário e a sobrevivência de larvas de primeiro ínstar eclodidas desses ovos. Larvas de primeiro, segundo e terceiro ínstares foram pulverizadas com os inseticidas, verificando-se a sobrevivência das pupas obtidas, e a viabilidade dos ovos produzidos pelos adultos emergidos. Esfenvalerate e triflumurom provocaram aumento do período embrionário de C. externa, sendo que nenhum dos inseticidas avaliados causou redução na viabilidade dos ovos. Endosulfam, fempropatrina, triclorfom e triflumurom foram altamente tóxicos à fase larval do predador, acarretando mortalidade de 71% a 100%. Esfenvalerate causou mortalidade média de 20% para larvas de primeiro e terceiro ínstares e de 38% para o segundo ínstar, não afetando a viabilidade das pupas obtidas e a capacidade reprodutiva dos adultos, apresentando possibilidades de recomendação para uso em programas de manejo integrado de pragas na cultura do algodoeiro. PALAVRAS-CHAVE: Crisopídeo, produto fitossanitário, controle biológico A cultura do algodoeiro possui importantes insetos-praga que causam danos consideráveis, destacando-se o curuquerê Alabama argillacea (Hübner). Em altas infestações, essa espécie pode causar prejuízos, desfolhando as plantas prematuramente e incapacitando-as de produzir sementes e fibras maduras. Muitas vezes o manejo desse inseto é realizado com uso de produtos de amplo espectro de ação que podem afetar os insetos benéficos presentes nessa cultura (Gridi-Papp et al. 1992).Os crisopídeos têm despertado interesse dos pesquisadores por serem eficientes predadores de ampla diversidade de presas, tais como pulgões, moscas-brancas, cochonilhas, lagartas, ácaros etc., podendo ser úteis em programas de manejo integrado de pragas para várias cultur...

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