Fungos entomopatogênicos para o controle da mosca-dos- chifres Haematobia irritans em laboratório e campo

A mosca-dos-chifres Haematobia irritans é um dos principais ectoparasitos associados a bovinos em pastagens. O presente trabalho objetivou analisar a ação patogênica dos isolados E9, IBCB425 e IBCB159 do fungo Metarhizium anisopliae, JAB06, JAB07 e AM09 de Beauveria bassiana, IBCB133 e CB75 de Isaria fumosorosea (=Paecilomyces fumosoroseus) e CG189 e CG195 de Isaria farinosa (=Paecilomyces farinosus) para a mosca-dos-chifres H. irritans em laboratório e campo. Avaliou-se em laboratório, a ação de todos os isolados dos fungos sobre ovos, larvas, pupas e adultos. Grupos de 30 ovos foram inoculados com suspensões fúngicas, e colocados sobre papel de filtro esterilizado, em 5 g de fezes bovinas frescas, acondicionadas em tubos de plástico. No ensaio com larvas, pedaços de papel filtro esterilizado contendo na superfície grupos de 30 ovos foram colocados sobre 5 g de fezes bovinas frescas, contidas em tubos de plástico, às quais incorporaram-se diversas concentrações de conídios mg fezes-1. No ensaio com ovos e larvas, o término do experimento ocorreu com a emergência dos adultos. Grupos de 20 pupas foram imersas por 60 segundos em suspensão do fungo, e colocadas em placas de Petri. Após a emergência, os adultos foram transferidos para gaiolas de isopor pequenas. Para o ensaio com adultos, grupos de 30 adultos foram separados e pulverizados com 0,3 mL das suspensões de conídios. Doze horas após, as moscas foram transferidas para gaiolas de isopor e avaliadas diariamente até o 15o dia. Para todos os ensaios, foram utilizadas suspensões contendo 106, 107 e 108 conídios mL-1. O isolado que promoveu os melhores resultados nos ensaios anteriores, foi usado em um experimento de campo para avaliar a ação fúngica em larvas e adultos de H. irritans em bovinos naturalmente infestados. Para o controle de larvas, foi oferecido aos bovinos conídios de M. anisopliae isolado...Horn fly Haematobia irritans is one of the main ectoparasites associated to cattle on pastures. The present work had the objective of analyzing the pathogenic action of the isolates E9, IBCB425 and IBCB159 of the fungus Metarhizium anisopliae, JAB06, JAB07 and AM09 of Beauveria bassiana, IBCB133 and CB75 of Isaria fumosorosea (=Paecilomyces fumosoroseus) and CG189 and CG195 of Isaria farinosa (=Paecilomyces farinosus) for horn fly H. irritans, in laboratory and field conditions. The action of all the fungi isolates over the eggs, larvae, pupae and adults were evaluated in laboratory. Groups of 30 eggs were inoculated with fungal suspensions and placed over sterilized filter paper on top of 5 g of fresh bovine feces, put in plastic tubes. In the larvae assay, peaces of sterilized filter paper, containing groups of 30 eggs on the surface, were placed over 5 g of fresh bovine feces, contained in plastic tubes, in which different concentrations of conidia mg feces-1 were incorporated. In the eggs and larvae assay, the end of the experiment matched the emergence of the adults. Groups of 20 pupae were immersed for 60 seconds in the fungus suspension and placed on Petri dishes. After the emergence, the adults were transferred to small Styrofoam cages. In the adults assay, groups of 30 adults were separated and pulverized with 0,3 ml of the conidia suspensions. After twelve hours, the adults were transferred to Styrofoam cages and the evaluations were done daily until the 15th day. Suspensions containing 106, 107 and 108 conidia ml-1 were used for all the assays. The isolate that promoted best results on the previous assays was used in a field experiment, where the fungal action on larvae and adults of H. irritans, on naturally infested bovines, was evaluated. For the larvae control conidia of the E9 isolate of M. anisopliae, microencapsulated... (Complete abstract click electronic access below)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Reaction of Bipolaris euphorbiae to environmental factors and its tolerance to solar and ultraviolet radiation

The determination of the ideal cultivation conditions and the knowledge of solar radiation tolerance are important aspects that must be investigated for the use of Bipolaris euphorbiae Muchovej and Carvalho as a biocontrol agent. The present study was done to assess the growth rate, sporulation and viability of the fungus cultivated under different conditions of the initial pH value of the growth medium, temperature and photoperiod. The tolerance of this fungus' conidia to light from a source simulating solar and ultraviolet radiation was also assessed. B. euphorbiae was affected by different pH values of the growth medium being 6.0 the adequate pH for fungus cultivation. Incubation of the fungus under temperatures of 22, 25 and 28A degrees C enhanced mycelium growth, while sporulation and viability of conidia were better at 22 and 16A degrees C. Different regimens of exposure to light of fungal cultures only affect sporulation. Conidia exposed to solar and ultraviolet radiation for 8 h and 90 min, respectively, presented viabilities higher than 92%, indicating high tolerance levels to radiation exposure.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Compatibilidade de isolados de Beauveria bassiana a inseticidas, herbicidas e maturadores em condições de laboratório

RESUMO: Foram avaliadas as diferenças de toxicidade de inseticidas, herbicidas e maturadores para os isolados AM 09, JAB 07, IBCB 07 e JAB 46 de Beauveria bassiana, por intermédio de experimentos realizados em meio de cultura. Os isolados foram inoculados em meio de batata, dextrose e ágar (BDA) contendo os agroquímicos. Foram avaliados a germinação, o crescimento e a esporulação e, com base nesses parâmetros, fez-se a classificação toxicológica dos agroquímicos para cada isolado. O inseticida Actara 250 WG(r) foi considerado compatível com AM 09, moderadamente tóxico para JAB 07 e tóxico para IBCB 07 e JAB 46. O Regente WG 800(r) foi considerado compatível com todos os isolados, já o Temik 150(r) se mostrou tóxico. Quanto aos herbicidas, o produto Glifosato Nortox(r) foi considerado compatível com AM 09, moderadamente tóxico para IBCB 07 e JAB 46 e tóxico para JAB 07. Plateau(r) foi classificado como moderadamente tóxico para AM 09 e JAB 07 e tóxico para IBCB 07 e JAB 46. Contain(r), DMA(r), Karmex(r), Sencor 480(r) e Velpar-K(r) foram classificados como tóxicos para todos os isolados. Tratando-se dos maturadores, tanto Curavial K(r) quanto Moddus(r) se mostraram tóxicos para todos os isolados. Os resultados revelaram que há variação entre os isolados de B. bassiana quanto à toxicidade dos agroquímicos. AM 09 foi o mais tolerante à ação tóxica dos produtos. A germinação sofreu menor efeito do que o crescimento e a esporulação, e JAB 07 foi o isolado menos afetado pelos agroquímicos com relação a esse parâmetro

Resíduos e subprodutos agroindustriais e grãos como substratos para produção do fungo entomapatogênico Lecanicillium lecanii

Lecanicillium lecanii é um fungo promissor no controle biológico de pragas e para sua utilização em campo é necessária a produção de conídios em grande quantidade. Este trabalho objetivou selecionar meios de cultura líquidos feitos com resíduos ou subprodutos agroindustriais e meios sólidos pela mistura de grãos e derivados, visando à produção dos isolados JAB 02 e JAB 45 do fungo. Como substratos líquidos utilizaram-se, em diferentes concentrações, água do cozimento do arroz e da prensa da mandioca, soro de queijo, milhocina®, melaço, vinhaça e leite de levedura da indústria da cana, avaliando-se a esporulação e biomassa. Como substratos sólidos, combinaram-se, em diferentes proporções, trigo grosso, farelos de trigo e de soja com quirela de milho, lentilha e sorgo para JAB 02, e com painço, trigo em grão e lentilha para JAB 45, avaliando-se a produção e viabilidade de conídios. O meio contendo 4% de milhocina® favoreceu a produção de ambos os isolados. Para JAB 02, proporcionaram melhores resultados os meios com 85% de água da prensa da mandioca, 5,5% de melaço e 100% de soro de queijo, além de misturas entre trigo grosso e farelo de trigo com lentilha (70:30%) e trigo grosso e farelo de trigo com sorgo (85:15%). Os meios com 100% da água da prensa da mandioca e 85% de soro de queijo, e as misturas entre farelo de trigo e painço (85:15%), trigo grosso e lentilha (55:45%) e farelo de trigo com trigo em grão e com lentilha (70:30%) favoreceram a produção de JAB 45.Lecanicillium lecanii is a fungus that shows much promise as a biological control agent against plague. To explore this possibility in field conditions conidia would have to be produced in large scale. With this dim, the present study selected substrates that could be used as media for cultivating isolates JAB 02 and JAB 45 from this fungus. Liquid media prepared with agro industrial by-products and residue, and solid media using mixtures of grain and derivates were tested. For liquid media different concentrations of water obtained from cooking rice and from squeezing dry cassava root, besides cheese whey , milhocina®, sugar cane molasses, vinasse and cream yeast from sugar cane milling, were assessed regarding spore production and biomass. Considering solid media, ground wheat, wheat and soy brans with broken corn, lentil seed and sorghum were all combined in different proportions for JAB 02, and with millet seed, wheat grain and lentil seed for JAB 45. These were assessed regarding conidia productivity and viability. The medium containing 4% milhocina® promoted good productivity from both isolates. Regarding JAB 02, the substrates containing 85% water from the squeezed cassava, 5,5% of molasses and 100% cheese whey, besides the mixtures of ground wheat and wheat bran with lentil seed (70:30%) and ground wheat and wheat bran with sorghum (85:15%) produced the best results. The media containing 100% water from the squeezed cassava with 85% cheese whey; and the mixtures of wheat bran plus millet seed (85:15%); ground wheat and lentil seed (55:45%); and wheat bran with wheat grain plus with lentil seed (70:30%) favored productivity in the JAB 45 isolate.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Efficiency of entomopathogenic fungi in the control of eggs and larvae of the horn fly Haematobia irritans (Diptera: Muscidae)

The present study assessed the pathogenic effect of isolates E9, IBCB425 and IBCB159 of the Metarhizium anisopliae fungus, JAB06, JAB07 and AM09 of Beauveria bassiana, IBCB133 and CB75 of Isaria fumosorosea (=Paecilomyces fumosoroseus) and CG189 and CG195 of Isaria farinosa (=Paecilomyces farinosus) against eggs and larvae of the horn fly Haematobia irritans. Eggs were inoculated with suspensions containing 10(6), 10(7) and 10(8) conidia ml(-1) of the fungal isolates and observed after 48 h to determine viability. In the larvae study, eggs were allowed to hatch into fresh bovine feces that had been treated with 10(8), 10(7) or 10(6) conidia mg feces(-1). In both studies, 5 days after initial procedures, all formed pupae were transferred to an incubator at 27 +/- 0.5 degrees C until the emergence of the adult flies was complete. The M. anisopliae isolates did not cause the death of H. irritans eggs, but they did promote the death of larvae that hatched from treated eggs, and therefore increased the total mortality. Isolate E9 promoted 100% mortality of treated larvae at a concentration of 10(8) conidia ml(-1). For the B. bassiana isolates, no activity was observed against insect eggs or larvae. Both L fumosorosea isolates promoted significant mortality (p < 0.05) of eggs at every concentration of conidia. Isolate CG195 of L farinosa increased the mortality of larvae and pupae that hatched from treated eggs and promoted significant total mortality (p < 0.05) of the insect at every concentration of conidia. (C) 2009 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Entomopathogenic fungal activity against pupae and adult Haematobia irritans (Diptera: Muscidae)

The horn fly Haematobia irritans is one of the most important ectoparasites associated with grazing bovines This study investigated the pathogenic activity of Metarhizium anisciphae (E9, IBCB425 and IBCB159), Beativeria bassiana (JAB06, JAB07 and AM09), Isaria fumoscrosea (=Paecilomyces fumosoroseus) (IBCB133 and CB75) and Isaria farinosa (=Paecilomyces fannosus) (CG189 and CG195) fungi isolates on pupae and adult 11 irritans Groups of 20 pupae and 30 adult flies were respectively battled and sprayed with fungal isolate Suspensions containing to10(6), 1(0)7 and 10(8) conidia ml(-1) in bioassays conducted in laboratories In both assays the adult flies were fed bovine blood for 15 days, and death rates were assessed daily The E9 and IBCB425 M anisophae isolates caused pupae death at concentiations of 10(7) and 10(8) conidia ml(-1), and the JAB07 and AM09 B bassiana isolates Caused higher Pupae mortality at a concentration of 10(8) conidia ml(-1) 1 farmosa isolates were the most effective considering Pupae mortality, with the CG195 inducing more deaths (56 6%)in the 10(8) conidia ml(-1) concentration Suspension. Adult flies were more Susceptible to the fungi's pathogenic action, since the E9 isolate of M anisophae and all of the B bassiana induced death in 100% of the flies at the 10(8) conidia ml(-1) concentration Suspension The I fumosorosea and I farmosa isolates, oil the other hand, were less effective in controlling adult flies. In both stages. but mostly the adult phase, pathogenicity was great at higher conidial concentrations; (C) 2009 Elsevier B V All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Susceptibility of adult and larval stages of the horn fly, Haematobia irritans, to the entomopathogenic fungus Metarhizium anisopliae under field conditions

The efficacy of M. anisopliae strain E9 as a biological insecticide for the adult and larval stages of H. irritans was assessed under field conditions. To assess larvicidal activity, nine heifers were randomly divided into three groups, which were maintained separated from each other. The first group ingested fungal spores encapsulated in alginate pellets. The second group ingested in natura spores that were grown on sterilized rice. In both groups, each animal received three meals a day, with each meal containing 2 x 10(10) conidia. The third group received no treatment and was used as a control. Fecal samples from manure and whole dung pats were collected from each of the three separate pastures on the day that the animals were allocated and on days 1, 3,6,9 and 12 afterwards. The fecal samples were tested for the presence of fungal colony forming units (CFU), and the emergence of horn flies was observed in the dung pats. Significantly less (P < 0.01) adult horn flies were found in dung pats of the group treated with encapsulated fungi (11.7) than in those from the heifers treated with conidia in natura (27.9) or from the control group (29.5). The fecal samples of the treated animals presented significantly higher numbers of M. anisopliae CFUs then those from the untreated controls. We found that on day 9 fecal samples from animals given microencapsulated conidia had significantly higher CFUs than those from animals treated with conidia in natura. To assess adulticide activity, four heifers were sprayed with a suspension of 3 x 10(10) aconidia l(-1) of M. anisopliae, and four control animals were sprayed with the same solution without conidial content. Four sprayings were done at five-day intervals, and all animals were photographed daily to observe the quantity of flies present. After the second spraying, we observed an average of 22.9 flies per animal; untreated heifers had an average of 43 flies per animal; thus, the treatment significantly (P < 0.05) decreases fly infestation. The results obtained from both tests show that M. anisopliae strain E9 has a pathogenic effect on H. irritans larvae in bovine manure when administered orally and on adult fly infestations when applied as a spray on the hosts. (C) 2009 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Population density of Beauveria bassiana in soil under the action of fungicides and native microbial populations

<div><p>ABSTRACT. This study investigated whether populations of naturally-occurring soil bacteria, fungi and actinomycetes influence the effect of fungicides on the survival and growth of Beauveria bassiana. The toxicity of methyl thiophanate, pyraclostrobin, mancozeb and copper oxychloride at the recommended doses was analyzed in culture medium and in soil inoculated with fungus at various time points after addition of fungicides. All fungicides completely inhibited the growth and sporulation of B. bassiana in the culture medium. The fungicides were less toxic in soil, emphasizing the action of the microbial populations, which interfered with the toxic effects of these products to the fungus. Actinomycetes had the greatest influence on the entomopathogen, inhibiting it or degrading the fungicides to contribute to the survival and growth of B. bassiana in soil. Native populations of fungi and bacteria had a smaller influence on the population density of B. bassiana and the action of fungicides towards entomopathogen. The toxic effect of the fungicides was greater when added to the soil one hour before or after inoculation than at 48h after inoculation.</p></div