RESUMO

Use of pesticides in agroecosystems is considered a major cause of bees diversity losses in the Neotropics, where Plebeia emerina (Friese) and Tetragonisca fiebrigi (Schwarz) (Hymenoptera: Apidae: Meliponini) are wild pollinators of native and crop plants. The aim of this study was to know the acute lethal toxicity of acetamiprid, malathion, phosmet and spinosad insecticides on P. emerina and T. fiebrigi. We obtained the mean concentration and mean lethal dose (LC50 and LD50) and the mean survival of workers after oral and topical exposure to insecticides, respectively. The LC50 values (ng a.i./µl of diet) and the decreasing order of toxicity for P. emerina was spinosad (4.96) > malathion (18.75) > phosmet (97.33) > acetamiprid (4204.06), and for T. fiebrigi also was spinosad (5.65) > malathion (8.39) > phosmet (53.91) > acetamiprid (9841.32), when orally exposed. The LD50 values (ng a.i./bee) and the decreasing order of toxicity for P. emerina was spinosad (1.90) > malathion (10.90) > phosmet (19.54) > acetamiprid (6216.55) and for T. fiebrigi was malathion (29.29) ≥ spinosad (29.79) > phosmet (41.95) > acetamiprid (1421.23), when topically exposed. The mean survival (hours) of contaminated bees by malathion, phosmet, and spinosad, was 11.81, 7.20, and 12.32 for P. emerina and 8.55, 7.20, and 13.34 for T. fiebrigi when orally exposed; and was 4.87, 9.87 and 11.17 for P. emerina, and 4.87, 4.76, and 19.05 for T. fiebrigi when topically exposed. Malathion, phosmet, and spinosad were highly toxic, while acetamiprid was moderately toxic. Our results indicated that the insecticides tested, mainly malathion, phosmet, and spinosad may be harmful to P. emerina and T. fiebrigi, making it essential to propose measures to minimize their impact on wild pollinators.

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The search for new safer insecticides has increased in recent agriculture. Botanical compounds such as terpenoids and plant essential oils with insecticidal activity could represent important tools in pest management, and their risk assessment against non-target organisms is necessary since they may serve as a precursor for the synthesis of new insecticide active ingredients. For this study, the acute toxicity and sublethal effects of seven terpenoids and three essential oils with recognized insecticidal activity were evaluated on the predator Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) in laboratory bioassays. Results indicate that these compounds feature relative selectivity to the predator C. externa; however, sublethal effects on reproduction were recorded for some compounds. The phenolic monoterpenoids carvacrol and thymol were more acutely toxic than other terpenoids screened, with LD50 <20,000 µg/g; however, they were less toxic than natural pyrethrins (toxicity standard) in these bioassays. Sublethal effects on fecundity and fertility were observed for R-(+)-limonene, while oregano oil only affected fecundity. The compounds evaluated here have potential to be used as insecticides and can serve as backbone for future synthesis of selective active ingredients; however, a complete risk assessment to C. externa and other non-target organisms is necessary for their incorporation in future crop protection paradigms.

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The use of insecticides, herbicides, and fungicides commonly occurs in mixtures in tanks in order to control phytosanitary problems in crops. However, there is no information regarding the effects of these mixtures on non-target organisms associated to the rice agroecosystem. The aim of this study was to know the toxicity of pesticide tank mixtures from rice crops against Telenomus podisi Ashmead (Hymenoptera: Platygastridae). Based on the methods adapted from the International Organisation for Biological and Integrated Control of Noxious Animals and Plants (IOBC), adults of T. podisi were exposed to residues of insecticides, herbicides, and fungicides, individually or in mixture commonly used by growers, in laboratory and on rice plants in a greenhouse. The mixture between fungicides tebuconazole, triclyclazole, and azoxystrobin and the mixture between herbicides cyhalofop-butyl, imazethapyr, imazapyr/imazapic, and penoxsulam are harmless to T. podisi and can be used in irrigated rice crops without harming the natural biological control. The insecticides cypermethin, thiamethoxam, and bifenthrin/carbosulfan increase the toxicity of the mixtures in tank with herbicides and fungicides, being more toxic to T. podisi and less preferred for use in phytosanitary treatments in the rice crop protection.

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RESUMO

Anastrepha fraterculus (Wied.) is the main insect pest of table grapes (Vitis vinifera) in the Southern Region of Brazil. In this study, we aimed to investigate the effect of fruit puncturing by adult females and larval infestation by A. fraterculus on the occurrence of bunch rot disease in the grape (cultivar "Itália") by evaluating grapes (a) punctured for oviposition by females of A. fraterculus, sterilized in laboratory with novaluron (40 mg L(-1)) and further spray-inoculated separately with Botrytis cinerea (1 × 10(6) conidia mL(-1)), Glomerella cingulata (1 × 10(6) conidia mL(-1)), and bacteria and yeast that cause sour rot (1 × 10(5) cells mL(-1)), (b) grapes punctured for oviposition by non-sterilized females with pathogen spraying, (c) grapes with mechanical wounds and pathogen spraying, (d) grapes with no wounds and with pathogen spraying, (e) grapes punctured for oviposition by A. fraterculus chemically sterilized in laboratory with novaluron, (f) grapes punctured for oviposition by A. fraterculus non-sterilized in laboratory with novaluron, (g) grapes with mechanical wounds, and (h) grapes with no sterilization or pathogen spraying. Our data indicated that the mechanical and oviposition wounds caused by A. fraterculus increased the percentage of grapes infected by B. cinerea, G. cingulata, and microorganisms of acid rot. The grape puncturing by A. fraterculus and the mechanical wound allows the penetration of B. cinerea and microorganisms leading to acid rot. We conclude that the fruit fly A. fraterculus may facilitate phytopathogens penetration leading to bunch rots in the table grape Itália.

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RESUMO

Aganaspis pelleranoi (Brèthes, 1924) (Hymenoptera: Figitidae) is a koinobiont endoparasitoid of larvae of species of the genus Anastrepha and of Ceratitis capitata. It is a candidate for use as a biological control agent, as under field conditions, it may reach a parasitism rate of 62%. The objective of this study was to determine the effect of different constant temperatures on biological parameters of A. pelleranoi when parasitizing the larva of Anastrepha fraterculus (Wiedemann, 1830) (Diptera: Tephritidae), as well as to determine its thermal requirements. The study was conducted in environmental chambers at 18, 20, 22, 25, 28, and 30 ± 1°C; 70 ± 10% relative humidity; and a 12-h photophase. Females maintained at 18 and 20°C produced more progeny than females at other temperatures tested. The longevity of males and females was inversely proportional to temperature, ranging from 49.1 to 3.73 d for females and from 32.1 to 3.8 d for males at temperatures of 18-30°C, respectively. The duration of the biological cycle (egg-to-adult) was influenced by temperature, and ranged from 69.1 d at 18°C to 30 d at 25°C. No preimaginal development of A. pelleranoi occurred at 28 and 30°C. The relationship between temperature and the demographic parameters of A. pelleranoi showed a linear effect over the temperature range of 18-25°C. The lower temperature threshold and thermal constant were 11.69°C and 391.70 degree days, respectively.

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RESUMO

O objetivo do presente trabalho foi avaliar a seletividade dos inseticidas utilizados na cultura do milho sobre Doru lineare. Foi avaliada a seletividade de inseticidas utilizados na cultura do milho para D. lineare, seguindo metodologia proposta pela IOBC/WPRS em condições de laboratório. Adultos foram expostos aos resíduos dos inseticidas por meio de contato com placas de vidros e pelo consumo de ovos de Spodoptera frugiperda contaminados com os inseticidas. A porcentagem de mortalidade dos insetos em contato residual foi utilizada para classificar os inseticidas como inócuo (< 30%), levemente nocivo (30-79%), moderadamente nocivo (80-99%) e nocivo (> 99%). A mortalidade de adultos após consumo de ovos contaminados foi comparada com a testemunha. Para adultos deD. lineare mediante contato residual, nas 360 HAIE (horas após o início da exposição), os inseticidas Decis 25 EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR, Match EC, Neem Azal e Sevin 480 SC foram nocivos ao predador. Certero, Fastac 100 SC e Tracer foram moderadamente nocivos. Intrepid 240 SC e Mimic 240 SC foram inócuos. A mortalidade de adultos após o consumo de ovos contaminados foi significativa para os inseticidas Certero, Dimilin, Tracer, Engeo Pleno, Lorsban 480 BR, Sevin 480 SC.

The objective of this work was to evaluate the selectivity of insecticides used in the corn crop to Doru lineare (Eschscholtz, 1822) (Dermaptera: Forficulidae), following methodology suggested by IOBC/WPRS, under laboratory conditions. Adult insects were placed on glass plates or fed on Spodoptera frugiperda eggs, both containing previously sprayed insecticide residues. The adult mortality by the residual contact was used to classify insecticides as harmless (< 30%), slightly harmful (30-79%), moderately harmful (80-99%) and harmful (> 99%). The adult mortality due to consumption of the contaminated eggs was compared to the control. For adults ofD. linearein residual contact after 360 HASE (hours after start of exposure) the insecticides Decis 25 EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR, Match EC, Neem Azal and Sevin 480 SC were harmful. Certero, Fastac 100 SC and Tracer were moderately harmful. Intrepid 240 SC and Mimic 240 SC were slightly harmful. The mortality of adults after consumption of contaminated eggs was noteworthy for the insecticides Certero, Dimilin, Tracer, Engeo Pleno, Lorsban 480 BR and Sevin 480 SC.

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RESUMO

O objetivo do trabalho foi avaliar a seletividade de inseticidas usados na cultura do milho para o controle de Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) sobre ninfas de primeiro ínstar e ovos do predador Doru lineare (Scudder, 1876) (Dermaptera: Forficulidae). Para os bioensaios foi utilizada a metodologia padronizada da IOBC/WPRS, em condições de laboratório, com temperatura de 25 ± 1º C, umidade relativa de 70 ± 10% e fotofase de 14 horas. No bioensaio com ninfas para contato residual, a aplicação dos inseticidas foi realizada com um equipamento pressurizado a CO2, pressão de 50 psi. Para aplicação dos inseticidas sobre os ovos foi utilizada torre de Potter, com pressão de 10 psi. Em ambas as formas de aplicação o depósito foi de 1,75 ± 0,25 mg de calda cm-2 conforme metodologia da IOBC/WPRS. A mortalidade de ninfas foi utilizada para classificar os inseticidas como inócuo (< 30%), levemente nocivo (30-79%), moderadamente nocivo (80-99%) e nocivo (> 99%). Os dados de viabilidade de ovos e sobrevivência de ninfas que eclodiram deles foram comparados com os dados das testemunhas positiva (Sevin 480 SC) e negativa (água). Certero, Dimilin, Engeo Pleno, Karate Zeon 250 SC, Lorsban 480 BR, Match EC e Sevin 480 SC reduziram a viabilidade de ovos. A sobrevivência de ninfas provenientes dos ovos tratados teve redução para os inseticidas: Decis 25 EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR e Sevin 480 SC. Para ninfas de D. lineare em contato residual, todos os inseticidas foram nocivos em 96 horas após a exposição.

The goal of this work was to evaluate the selectivity of insecticides used in corn crops for the control of Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) on first-instar nymphs and eggs of the earwig Doru lineare. For the bioassays the standardized methodology of IOBC/WPRS was used in terms of temperature (25 ± 1º C), relative humidity (70 ± 15%) and photophase (14 hours). In the bioassay with nymphs for residual contact, the applications of insecticides was conducted with equipment pressurized by CO2 to 50 psi. For applications of insecticides on eggs, a Potter's tower was used, with pressure of 10 psi. In both forms of spraying the deposit was 1.75±0.25 mg cm-2 of aqueous solution in accordance with the IOBC/WPRS methodology. The mortality of nymphs was used to classify insecticides as harmless (< 30%), slightly harmful (30-79%), moderately harmful (80-99%) and harmful (> 99%). Viability of eggs and survival of hatched nymphs were both evaluated by comparing with the positive (Sevin 480 SC) and negative (water) controls. The viability of eggs was reduced by Certero, Dimilin, Engeo Pleno, Karate Zeon 250 SC, Lorsban 480 BR, Match EC and Sevin 480 SC. The survival of nymphs from treated eggs was reduced by the insecticides Decis EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR and Sevin 480 SC. For nymphs of D. lineare in residual contact, all the insecticides were harmful.

Assuntos

RESUMO

ABSTRACT The objective of this work was to evaluate the selectivity of insecticides used in the corn crop to Doru lineare (Eschscholtz, 1822) (Dermaptera: Forficulidae), following methodology suggested by IOBC/WPRS, under laboratory conditions. Adult insects were placed on glass plates or fed on Spodoptera frugiperda eggs, both containing previously sprayed insecticide residues. The adult mortality by the residual contact was used to classify insecticides as harmless ( 30%), slightly harmful (30-79%), moderately harmful (80-99%) and harmful (> 99%). The adult mortality due to consumption of the contaminated eggs was compared to the control. For adults ofD. linearein residual contact after 360 HASE (hours after start of exposure) the insecticides Decis 25 EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR, Match EC, Neem Azal and Sevin 480 SC were harmful. Certero, Fastac 100 SC and Tracer were moderately harmful. Intrepid 240 SC and Mimic 240 SC were slightly harmful. The mortality of adults after consumption of contaminated eggs was noteworthy for the insecticides Certero, Dimilin, Tracer, Engeo Pleno, Lorsban 480 BR and Sevin 480 SC.

RESUMO O objetivo do presente trabalho foi avaliar a seletividade dos inseticidas utilizados na cultura do milho sobre Doru lineare. Foi avaliada a seletividade de inseticidas utilizados na cultura do milho para D. lineare, seguindo metodologia proposta pela IOBC/WPRS em condições de laboratório. Adultos foram expostos aos resíduos dos inseticidas por meio de contato com placas de vidros e pelo consumo de ovos de Spodoptera frugiperda contaminados com os inseticidas. A porcentagem de mortalidade dos insetos em contato residual foi utilizada para classificar os inseticidas como inócuo ( 30%), levemente nocivo (30-79%), moderadamente nocivo (80-99%) e nocivo (> 99%). A mortalidade de adultos após consumo de ovos contaminados foi comparada com a testemunha. Para adultos deD. lineare mediante contato residual, nas 360 HAIE (horas após o início da exposição), os inseticidas Decis 25 EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR, Match EC, Neem Azal e Sevin 480 SC foram nocivos ao predador. Certero, Fastac 100 SC e Tracer foram moderadamente nocivos. Intrepid 240 SC e Mimic 240 SC foram inócuos. A mortalidade de adultos após o consumo de ovos contaminados foi significativa para os inseticidas Certero, Dimilin, Tracer, Engeo Pleno, Lorsban 480 BR, Sevin 480 SC.

RESUMO

ABSTRACT The goal of this work was to evaluate the selectivity of insecticides used in corn crops for the control of Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) on first-instar nymphs and eggs of the earwig Doru lineare. For the bioassays the standardized methodology of IOBC/WPRS was used in terms of temperature (25 ± 1º C), relative humidity (70 ± 15%) and photophase (14 hours). In the bioassay with nymphs for residual contact, the applications of insecticides was conducted with equipment pressurized by CO2 to 50 psi. For applications of insecticides on eggs, a Potters tower was used, with pressure of 10 psi. In both forms of spraying the deposit was 1.75±0.25 mg cm-2 of aqueous solution in accordance with the IOBC/WPRS methodology. The mortality of nymphs was used to classify insecticides as harmless ( 30%), slightly harmful (30-79%), moderately harmful (80-99%) and harmful (> 99%). Viability of eggs and survival of hatched nymphs were both evaluated by comparing with the positive (Sevin 480 SC) and negative (water) controls. The viability of eggs was reduced by Certero, Dimilin, Engeo Pleno, Karate Zeon 250 SC, Lorsban 480 BR, Match EC and Sevin 480 SC. The survival of nymphs from treated eggs was reduced by the insecticides Decis EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR and Sevin 480 SC. For nymphs of D. lineare in residual contact, all the insecticides were harmful.

RESUMO O objetivo do trabalho foi avaliar a seletividade de inseticidas usados na cultura do milho para o controle de Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) sobre ninfas de primeiro ínstar e ovos do predador Doru lineare (Scudder, 1876) (Dermaptera: Forficulidae). Para os bioensaios foi utilizada a metodologia padronizada da IOBC/WPRS, em condições de laboratório, com temperatura de 25 ± 1º C, umidade relativa de 70 ± 10% e fotofase de 14 horas. No bioensaio com ninfas para contato residual, a aplicação dos inseticidas foi realizada com um equipamento pressurizado a CO2, pressão de 50 psi. Para aplicação dos inseticidas sobre os ovos foi utilizada torre de Potter, com pressão de 10 psi. Em ambas as formas de aplicação o depósito foi de 1,75 ± 0,25 mg de calda cm-2 conforme metodologia da IOBC/WPRS. A mortalidade de ninfas foi utilizada para classificar os inseticidas como inócuo ( 30%), levemente nocivo (30-79%), moderadamente nocivo (80-99%) e nocivo (> 99%). Os dados de viabilidade de ovos e sobrevivência de ninfas que eclodiram deles foram comparados com os dados das testemunhas positiva (Sevin 480 SC) e negativa (água). Certero, Dimilin, Engeo Pleno, Karate Zeon 250 SC, Lorsban 480 BR, Match EC e Sevin 480 SC reduziram a viabilidade de ovos. A sobrevivência de ninfas provenientes dos ovos tratados teve redução para os inseticidas: Decis 25 EC, Dimilin, Engeo Pleno, Karate Zeon 250 CS, Lorsban 480 BR e Sevin 480 SC. Para ninfas de D. lineare em contato residual, todos os inseticidas foram nocivos em 96 horas após a exposição.

RESUMO

ABSTRACT The effect of neonicotinoid insecticides (acetamiprid, imidacloprid and thiamethoxam) and growth regulators (buprofezin and pyriproxyfen) were evaluated for the control of citrus mealybug Planococcus citriin vineyards. The experiments were conducted in the greenhouse (1-year-old plants) and in a commercial vineyard (15-year-old plants) using the Cabernet Sauvignon cultivar. The insecticides acetamiprid (Mospilan, 0.6 g a.i./plant), imidacloprid (Confidor 700 GRDA, 0.7 g a.i./plant) and thiamethoxam (Actara 250 WG, 0.75 g a.i./plant) were applied into the soil using 200 and 1,000 mL of water per plant for the 1and 15year-old plants, respectively. In foliar spraying the insecticides acetamiprid (Mospilan, 6 a.i./100 L), buprofezin (Applaud 250, 25 g a.i./100 L), imidacloprid (Confidor 700 GRDA, 7g a.i./100 L), pyriproxyfen (Tiger 100 CE, 10 g a.i./100 L), tiametoxam (Actara 250 WG, 7.5 g a.i./100 L) and a control (only water) were evaluated only in 15-year-old plants. At 3, 7, 14, 21, 28, 35 and 60 days after insecticide application in the experiments applied into the soil and at 1, 5 and 10 days after foliar spraying, the leaves were removed from the plants and infested in the laboratory with first-instar nymphs (crawlers) from artificial rearing. In new plantings, the neonicotinoid insecticides acetamiprid, imidacloprid and thiamethoxam provided a mortality of 82, 94 and 82%, respectively, up to 35 days after application (DAA). In adult plants, only the insecticide imidacloprid reduced the infestation by 63% up to 7 DAA. The insecticides applied by foliar spraying acetamiprid, buprofezin, imidacloprid, thiamethoxam and pyriproxyfen were not effective for the control of P. citri in vineyards following the residual contact methodology.

RESUMO O efeito de inseticidas neonicotinoides (acetamiprido, imidacloprido e tiametoxam) e reguladores de crescimento (buprofezina e piriproxifem) foram avaliados para o controle dePlanococcus citri na cultura da videira. Os experimentos foram conduzidos em casa-de-vegetação (plantas com um ano) e vinhedo comercial (plantas adultas-15 anos) utilizando a cultivar Cabernet Sauvignon. Os inseticidas acetamiprido (Mospilan, 0,6 g i.a./planta), imidacloprido (Confidor 700 GRDA, 0,7 g i.a./planta) e tiametoxam (Actara 250 WG, 0,75 g i.a./planta) foram aplicados via solo utilizando 200 e 1.000 mL de água por planta com um ano e 15 anos, respectivamente. Em pulverização foliar foram avaliados somente em plantas adultas os inseticidas acetamiprido (Mospilan, 6 g i.a./100L); buprofezina (Applaud 250, 25 g i.a./100 L); imidacloprido (Confidor 700 GRDA, 7 g i.a./100 L), piriproxifem (Tiger 100 CE, 10 g i.a./100 L), tiametoxam (Actara 250 WG, 7,5 g i.a./100 L) e um tratamento testemunha (somente água). Aos 3, 7, 14, 21, 28, 35 e 60 dias após a aplicação dos inseticidas (DAA) nos experimentos via solo e 1, 5 e 10 (DAA) no experimento em pulverização foliar as folhas foram retiradas das plantas e infestadas em laboratório com ninfas de primeiro instar provenientes de criação artificial. Em plantas novas de um ano de idade os inseticidas neonicotinoides acetamiprido, imidacloprido e tiametoxam nas doses avaliadas foram eficazes proporcionando uma mortalidade de 82, 94 e 82%, respectivamente, até 35 dias após a aplicação. Em plantas adultas, somente o inseticida imidacloprido reduziu a infestação em 63% até 7 dias após a aplicação. Os inseticidas aplicados via pulverização foliar, acetamiprido, buprofezina, imidacloprido, tiametoxam e piriproxifem não proporcionaram mortalidade significativa de P. citri na cultura da videira.

RESUMO

ABSTRACT The side-effects of sixteen commercial formulations of insecticides registered for corn crops were assessed for Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) under laboratory conditions (25 ± 1o C temperature, 70 ± 10% relative humidity; 14h photophase and brightness 500 lux). The adult parasitoids were submitted to fresh dry insecticide film applied on glass plates, and the capacity of parasitism of the females was evaluated. The reduction in capacity of parasitism for the respective treatments was compared with the control (distilled water) and used to classify the insecticides into four categories: 1, harmless ( 30%); 2, slightly harmful (30 79%); 3, moderately harmful (8099%) and 4, harmful (> 99%). The pesticides (% active ingredient in spray water) Certero (0.012) and Rimon 100 EC (0.0075) were harmless; Fastac 100 SC (0.0025) and Match EC (0.0075) were slightly harmful; Tracer (0.024) was moderately harmful; Arrivo 200 EC (0.008), Decis 25 EC (0.0025), Deltaphos EC (0.00175 deltamethrin + 0.06125 triazophos), Dipterex 500 (0.5), Folidol 600 (0.15), Hostathion 400 BR (0.1), Karate Zeon 250 CS (0.0125), Malathion 500 CE Sultox (0.0625), Sumithion 500 CE (0.375), Turbo (0.0025) and Vexter (0.24) were harmful to adults of T. pretiosum in the test of initial toxicity under laboratory conditions.

RESUMO Foi avaliado o efeito de dezesseis formulações comerciais de inseticidas registrados para a cultura do milho sobre a capacidade de parasitismo de Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) em condições de laboratório (temperatura 25 ± 1o C, umidade relativa 70 ± 10%; fotofase 14 horas e luminosidade 500 lux). Adultos do parasitóide foram colocados em contato com uma película seca dos inseticidas pulverizados sobre placas de vidro e a capacidade de parasitismo das fêmeas foi mensurada. A redução na capacidade de parasitismo dos tratamentos foi comparada com a testemunha (água destilada) e utilizada para classificar os inseticidas em quatro classes: 1, inócuo ( 30%); 2, levemente nocivo (30-79%); 3, moderadamente nocivo (80-99%) e 4, nocivo (> 99%). Os inseticidas (% de ingrediente ativo na calda) Certero (0,012) e Rimon 100 EC (0,0075) foram inócuos; Fastac 100 SC (0,0025) e Match EC (0,0075) foram levemente nocivos; Tracer (0,024) foi moderadamente nocivo; Arrivo 200 EC (0,008), Decis 25 EC (0,0025), Deltaphos EC (0,00175 deltametrina + 0,06125 triazofós), Dipterex 500 (0,5), Folidol 600 (0,15), Hostathion 400 BR (0,1), Karate Zeon 250 CS (0,0125), Malathion 500 CE Sultox (0,625), Sumithion 500 CE (0,375), Turbo (0,0025) e Vexter (0,24) foram nocivos aos adultos de T. pretiosum no teste de toxicidade inicial em condições de laboratório.

RESUMO

ABSTRACT The effect of Bacillus thuringiensis and chemical insecticides (fenitrotion and trichlorfon) for the control of Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera: Tortricidae) was evaluated in the laboratory and in a commercial vineyard. In the laboratory at 26 ± 1º C, relative humidity of 70 ± 10% and 14h photophase, using grapevine leaves with artificial infestations of third to fourth instars, B. thuringiensis var. kurstaki (Dipel DF® 50, 75 and 100 g/100L), fenitrothion (Sumithion® 500 CE, 150 mL/100L) and triclorfon (Dipterex® 500, 300 mL/100L) were efficient for A. sphaleropa larvae control, reducing the insect population by more than 90%. In the commercial vineyard, A. sphaleropa adults continued being caught in pheromone traps during the whole experiment (from December of 2003 to March of 2004), with a peak at the beginning of February. In field conditions, all insecticides and doses reduced the South American tortricid moth damage in the bunches between 83.3 and 94.4%. The control of B. thuringiensis was equivalent to the chemical insecticides fenitrothion and trichlorfon.

RESUMO O efeito de Bacillus thuringiensis e inseticidas químicos (fenitrotion e triclorfon) para o controle de Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera: Tortricidae) foi avaliado em laboratório e vinhedo comercial. Em laboratório, a 26 ± 1º C, UR 70 ± 10% e fotofase de 14 horas, utilizando discos de folhas de videira com lagartas de terceiro e quarto ínstar, observou-se que os inseticidas B. thuringiensis var. kurstaki (Dipel DF®, 50, 75 e 100 g/100L), fenitrothion (Sumithion® 500 CE, 150 mL/100L) e triclorfon (Dipterex® 500, 300 mL/100L) foram eficientes no controle de A. sphaleropa, reduzindo a população em níveis superiores a 90%. Em vinhedo comercial, observou-se a presença constante de adultos de A. sphaleropa em armadilhas de feromônio sexual durante todo o experimento (dezembro de 2003 a março de 2004), constatando-se um pico populacional no início de fevereiro. Na colheita, todos os inseticidas e concentrações avaliadas reduziram significativamente o dano da lagarta-das-fruteiras nos cachos em níveis entre 83,3 a 94,4%, sendo que as três concentrações de B. thuringiensis foram equivalentes ao controle obtido com os inseticidas fosforados fenitrothion e triclorfon.

RESUMO

ABSTRACT In order to select an isolate of Metarhizium anisopliae promising for the microbial control of Tibraca limbativentris and to evaluate its virulence in all stages of development of this insect, two bioassays were carried out. Five isolates of M. anisopliae were applied using fungal suspension with 108 conidia/mL, in the following treatments: 1) control, 2) isolate CG 041, 3) CG 144, 4) CG 167, 5) CG 835 and 6) CG 891. To evaluate the virulence in the stages of development, a suspension with 108 conidia/mL from the isolate CG 891 was prepared and applied over the eggs, small nymphs (2nd and 3rd instars), large nymphs (4th and 5th instars) and adults. In the first experiment, the calculated TL50 values showed that the isolate CG 891 was the most virulent, and about 11 days were necessary to control 50% of the tested population. In the second experiment, designed for eggs, the TL50 value was 5.53 days, when 83% of contamination was observed, and none of the hatched nymphs reached the second instar. In the other treatments, the TL50 values were 6.61, 8.76 and 8.82 days for small nymphs, large nymphs and adults. Eggs, nymphs and adults of T. limbativentris were susceptible to M. anisopliae (isolate CG 891).

RESUMO Visando selecionar um isolado de Metarhizium anisopliae promissor para o controle microbiano de Tibraca limbativentris e avaliar sua virulência sobre as fases do desenvolvimento desse inseto, realizaram-se dois bioensaios. Cinco isolados de M. anisopliae foram aplicados usando-se em suspensões fúngicas de 108 conídios/mL, sendo definidos os tratamentos: 1) testemunha, 2) isolado CG 041, 3) CG 144, 4) CG 167, 5) CG 835 e 6) CG 891. Para avaliar a virulência sobre as fases do desenvolvimento preparou-se uma suspensão 108 conídios/mL do isolado CG 891 aplicando-a sobre ovos, ninfas pequenas (2º e 3º instares), ninfas grandes (4º e 5º instares) e adultos. No primeiro experimento, os valores de TL50 calculados mostraram que o isolado CG 891 foi o mais virulento, sendo necessários cerca de 11 dias para controlar 50% da população testada. No segundo experimento, para ovos, o TL50 foi de 5,53 dias, quando se observou 83% de contaminação, e nenhuma das ninfas eclodidas atingiu o segundo instar. Nos outros tratamentos, os valores de TL50 foram de 6,61, 8,76 e 8,82 dias para ninfas pequenas, ninfas grandes e adultos. Ovos, ninfas e adultos de T. limbativentris são suscetíveis de M. anisopliae (isolado CG 891).

RESUMO

ABSTRACT The South American tortricid moth Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera: Tortricidae) is often found damaging vineyards and other temperate fruits in Southern Brazil. In this study, neem oil (0.25 and 0.50%) incorporated to A. sphaleropa artificial diet increased larval phase, reduced larval and pupae viability, producing males with a reduced lifespan. Pyroligneous acid (0.50%) increased larval duration, reduced male longevity and the oviposition period without affecting fecundity. Using the fertility life table, neem oil (0.25 and 0.50%) and pyroligneous acid (0.50%) added to the artificial diet increased duration in days of one generation (T), the net reproductive rate (Ro), the intrinsic rate of increase (Rm) and the finite rate of increase (l) of A. sphaleropa when compared with diets without these compounds.

RESUMO A lagarta-das-fruteiras Argyrotaenia sphaleropa (Meyrick, 1909) (Lepidoptera:Tortricidae) é uma espécie freqüentemente encontrada danificando a cultura da videira e outras frutíferas temperadas na região da Encosta Superior do Nordeste do Rio Grande do Sul e no Uruguai. Neste trabalho, foi estudado em laboratório o efeito de inseticidas permitidos na produção orgânica quando fornecidos as lagartas em dieta artificial sobre o desenvolvimento de A. sphaleropa. O óleo de nim (0,25 e 0,50%), incorporados à dieta artificial de A. sphaleropa provocou um aumento na duração da fase de lagarta, menor viabilidade das fases de lagarta e pupa e menor longevidade de machos. O extrato pirolenhoso (0,50%) provocou aumento na duração da fase de lagarta, reduzindo a longevidade de machos e o período de oviposição, sem afetar a fecundidade. Com base na tabela de vida de fertilidade verificou-se que a presença do óleo de nim (0,25 e 0,50%) e do extrato pirolenhoso (0,50%) em dietas artificiais aumentaram a duração em dias de uma geração (T), a taxa líquida de reprodução (Ro), a razão infinitesimal de aumento populacional (Rm) e a razão finita de aumento () de A. sphaleropa quando comparado com a dieta sem os inseticidas.