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1.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 23(2, cont.): e2301, jul-dez. 2020. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1129392

RESUMO

Stingless bees Tetragonisca angustula (Latreille) (Hymenoptera: Meliponinae) are pollinators of native and cultivated plants and are therefore in contact with areas contaminated by pesticides. These native bees were evaluated for changes in gene expression of esterase isoenzymes (EST) and peptides after contamination by contact with growth regulators from insecticides Gallaxy® EC 100, Natuneem and Azamax after 48, 120, 168 hours, 30 and 60 days. EST-4 presented an increase in relative activity after contamination with Gallaxy® EC 100 at 6.2 × 10-2 g a.i./mL; Natuneem at 7.5 × 10-5 g a.i./mL; and Azamax at 1.2 × 10-3 g a.i/mL after 60 days, 48 h, and 60 days, respectively. Inhibition of the relative activity of EST-4 was detected after contamination by Natuneem at 1.5 × 10-5 g a.i./mL and Azamax at 1.2 × 10-3 g a.i./mL after 48 h and 30 days, respectively. The insecticide growth regulators promoted changes in protein synthesis of T. angustula adult workers resulting in an increase or decrease in the relative intensity of bands, and the appearance of new peptides when compared with controls. Changes in protein synthesis have been identified mainly after long period of contamination, 120 and 168 h with the IGRs Gallaxy® EC 100 (at 0.78 and 1.25 g a.i./mL), Azamax (at 1.2 × 10-3 and 6 × 10-3 g a.i./mL), and Natuneem (at 7.5 × 10-5 and 3 × 10-3 g a.i./mL), and at 60 days with Natuneem (at 1.5 × 10-5 g a.i./mL).(AU)


Abelhas sem ferrão Tetragonisca angustula (Latreille) (Hymenoptera: Meliponinae) são polinizadores de plantas nativas e cultivadas e, portanto, estão em contato com áreas contaminadas por biopesticidas. Essas abelhas nativas foram avaliadas quanto a alterações na expressão gênica de isoenzimas esterases (EST) e peptídeos após contaminação por contato com reguladores de crescimento de inseticidas Gallaxy® EC 100, Natuneem e Azamax após 48, 120, 168 horas, 30 e 60 dias. A EST-4 apresentou um aumento na atividade relativa após a contaminação com Gallaxy® 100 EC em 6,2 × 10-2 g i.a./mL, Natuneem em 7,5 × 10-5 g i.a./mL e Azamax em 1,2 × 10-3 g i.a./mL após 60 dias, 48 h e 60 dias, respectivamente. A inibição da atividade relativa de EST-4 foi detectada após contaminação pelo Natuneem a 1,5 × 10-5 g i.a./mL e Azamax a 1,2 × 10-3 g i.a./mL após 48 he 30 dias, respectivamente. Os reguladores de crescimento de inseticidas promoveram alterações na síntese protéica de trabalhadores adultos de T. angustula, resultando em um aumento ou diminuição da intensidade relativa das bandas e no aparecimento de novos peptídeos em comparação com os controles. Alterações na síntese de proteínas foram identificadas principalmente após um longo período de contaminação, 120 e 168 h com o IGRs Gallaxy® EC 100 (0,78 e 1,25 g i.a./mL), Azamax (1,2 × 10-3 e 6 × 10-3 g i.a./mL) e Natuneem (7,5 × 10-5 e 3 × 10-3 g i.a./mL) e 60 dias com Natuneem (1,5 × 10-5 g i.a./mL).(AU)


Las abejas sin aguijón Tetragonisca angustula (Latreille) (Hymenoptera: Meliponinae) son polinizadores de plantas nativas y cultivadas y, por lo tanto, están en contacto con áreas contaminadas por bioplaguicidas. Estas abejas nativas fueron evaluadas para detectar cambios en la expresión génica de isoenzimas esterasa (EST) y péptidos después de la contaminación por contacto con los reguladores del crecimiento insecticidas Gallaxy® EC 100, Natuneem y Azamax después de 48, 120, 168 horas, 30 y 60 días. EST-4 mostró un aumento en la actividad relativa después de la contaminación con Gallaxy® 100 EC a 6.2 × 10-2 g i.a./mL, Natuneem a 7.5 × 10-5 g i.a./mL y Azamax a 1.2 × 10-3 g i.a./mL después de 60 días, 48 hy 60 días, respectivamente. La inhibición de la actividad relativa de EST-4 se detectó después de la contaminación por Natuneem a 1.5 × 10-5 g i.a./mL y Azamax a 1.2 × 10-3 g i.a./mL después de 48 hy 30 días. respectivamente. Los insecticidas reguladores del crecimiento promovieron cambios en la síntesis de proteínas de trabajadores adultos de T. angustula, resultando en un aumento o disminución de la intensidad relativa de las bandas y en la aparición de nuevos péptidos en relación a los controles. Los cambios en la síntesis de proteínas se identificaron principalmente después de un largo período de contaminación, 120 y 168 h con IGRs Gallaxy® EC 100 (0.78 y 1.25 g i.a./mL), Azamax (1.2 × 10-3 y 6 × 10-3 g i.a./mL) y Natuneem (7.5 × 10-5 y 3 × 10-3 g i.a./mL) y 60 días con Natuneem (1.5 × 10-5 g i.a./mL).(AU)


Assuntos
Animais , Peptídeos , Reguladores de Crescimento de Plantas , Abelhas , Esterases , Inseticidas
2.
Rev. bras. entomol ; 63(4): 277-282, Out.-Dec. 2019. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1057794

RESUMO

ABSTRACT American bollworm (ABW), Helicoverpa armigera (Hubner), is considered as a major pest of cotton, Gossypium hirsutum, all over the globe. Due to its destructive feeding nature and continuous consumption of the same chemicals, it devolved resistant against many insecticides. Therefore, a combined application of bio- and synthetic-pesticide need to evaluate against this pest. The entomopathogenic viruses like nuclear polyhedrosis virus (NPV), a member of baculoviruses, can be the potential candidates for better control against ABW. The present study was conducted to assess the comparative efficacy of NPV and Spinosad 240SC (with the concentration of 250 mL · ha-1) against ABW in the controlled environment. The ABW was treated with different concentrations of NPV and Spinosad separately and in a combination of NPV with 0.1% Spinosad. The results revealed that highest concentrations showed highest mortality (95%) followed by 95%, 92%, 84%, 82% and 78% mortality at 1 × 109, 1 × 108, 1 × 107, 1 × 106 and 1 × 105 POBs, respectively. Spinosad when mixed in diet give 100% mortality at 0.8% followed by 50.87%, 42.10%, 29.82%, 26.31% and 22.80% mortality at 0.4%, 0.2%, 0.1%, 0.5% and 0.025% respectively. The results of this study revealed that microbial control of ABW through NPV is an effective tool. The repeated use of synthetic pesticides caused the resurgence of many insect pests, and this study results would provide useful insight to build a framework for future investigations for the management of many major insect pests.

3.
Malaysian Journal of Microbiology ; : 152-158, 2018.
Artigo em Inglês | WPRIM | ID: wpr-732371

RESUMO

@#Aims:The ever-revolving fungi strains and environmental and health concerns due to current practice of synthetic pesticide in agricultural fields have encourages more ventures into bio-pesticides research. Mimusops elengi, a widely available endogenous plant intropical countries and most parts of this plant have been proven to possess medicinal and antimicrobial potential. In this study, M.elengiseeds crude extracts are tested for their antifungal activities on paddy seed-borne and pathogenic fungi.Methodology and results:The dried and grinded M.elengiseeds are macerated separately using water, methanol, ethyl acetate, dichloromethane and petroleum ether as extraction medium. Crude extract of each solvent wasused on paddy seed surface treatment to determine their antifungal inhibition potential on seed-borne fungi and paddy grain germination. Synthetic fungicide mancozeb and thiram are also tested as comparisons to the performance of plant extracts. Water andmethanol extracts exerted the best fungal inhibiting and grain germination results from the five crude extracts tested and qualitative phytochemical screening reveals both extracts contained the most number of phytoconstituents including saponin, flavonoids, alkaloids, tannins and phenolic. Water extract, methanol extracts and synthetic fungicides are then subjected to in-vitro bioassay to observe their effect on mycelial growth of several fungi strains pathogenic to paddy namely, Fusarium fujikuroi,Curvularia aeria,C.lunata andC.eragrostidis.Water and methanol extracts showed a very similar trend of inhibition on all four fungi strains tested with best percentage of inhibition on mycelia growth of C.eragrostidisfollowed by C. aeria, C. lunataand least effective on F.fujikuroi. Further separation of crude extract need to be done to isolate the specific acting compounds contributing to fungal growth inhibition.Conclusion, significance and impact of study:Both water and methanol extracts of the seeds contain promising antifungal properties on seed borne fungi which is as good as the synthetic fungicides compared in this study. A broad range of active phytochemical properties it possesses may be the contributing factor for the fungal growth inhibition. This preliminary screening could narrow down the potential of this seed extracts as natural antifungal agents and the acting active compounds.

4.
Rev. colomb. biotecnol ; 19(1): 82-91, ene.-jun. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-900425

RESUMO

Resumen El hongo entomopatógeno Nomuraea rileyi (aislamiento Nm006) ha demostrado un alto potencial para ser utilizado en el control biológico de gusano cogollero del maíz Spodoptera frugiperda. Sin embargo, este microorganismo es altamente susceptible a condiciones abióticas de estrés, lo que dificulta el desarrollo tecnológico de un bioplaguicida. Teniendo en cuenta lo anterior, el objetivo del trabajo fue evaluar el efecto individual de temperatura y luz ultravioleta mediante choques de estrés implementados en el proceso de fermentación sólida. Los conidios obtenidos de los diferentes tratamientos se caracterizaron microbiológicamente (rendimiento y germinación), enzimática (β-esterasa, N-acetilglucosaminidasa y quimoelastasa proteasa Pr1) y biológicamente mediante un bioensayo. Los choques de temperatura no afectaron el rendimiento, germinación y actividad biológica del aislamiento, pero si potenciaron la actividad β-esterasa y la actividad N-acetilglucosaminidasa en comparación con los conidios no expuestos. Con respecto a los choques con luz UV, éstos no mejoraron las características de los conidios de N. rileyi. Con base en los resultados, los choques térmicos a 5 °C y 45 °C, se seleccionaron para la fermentación del hongo, porque no afectaron negativamente ninguna característica y aumentaron las actividades enzimáticas β-esterasa y N-acetilglucosaminidasa de los conidios, lo que podría mejorar la actividad insecticida sobre S. frugiperda.


Abstract The entomopathogenic fungus Nomuraea rileyi (isolate Nm006) is a possible microbial control agent against "fall armyworm" Spodoptera frugiperda. However, this fungus is affected by abiotic stress conditions that cause a slow development of the biopesticide. The objective of this study was to assess the individual effect of abiotic stress (temperature and UV light) during solid fermentation of Nomuraea rileyi Nm006. Conidia were produced under different stress conditions and then characterized microbiologically (yield and germination), enzymatically (β-esterese, N-acetylglucosaminidase and subtilin-like protease Pr1) and biologically against Spodoptera frugiperda. All the treatments were compare with conidia produced without stress. Yield and N-acetylglucosaminidase activity did not improve in conidia produced under temperature stress. Germination, efficacy and β-esterase activity were significantly higher in conidia exposed to thermal shock compared to unexposed conidia. UV light shocks did not improve any characteristics of Nm006. Thermal stress at 5 °C and 45 °C were select for fungus fermentation because conidia had higher enzymatic activity (β-esterase y N-acetilglucosaminidase) and any characteristic was negatively affect. This thermal stress could be a strategy to improve the insecticidal activity against S. frugiperda.

5.
Rev. bras. plantas med ; 17(2): 291-296, Apr-Jun/2015. tab, graf
Artigo em Português | LILACS | ID: lil-746131

RESUMO

RESUMO: Estudou-se o efeito de extratos aquosos de inhame (0; 5; 10; e 20% p/p) e de mastruz (0; 2; 4; 6; 8 e 10% p/p) na biologia da lagarta-do-cartucho. Secções de folhas de milho foram mergulhadas por 30 segundos em soluções de cada concentração; após a secagem, colocou-se em cada secção uma lagarta recém-eclodida. Foram avaliadas a viabilidade e a duração das fases larval e pupal, peso e comprimento das lagartas e pupas. Em relação ao extrato de inhame, a concentração de 20% causou maior influência na fase larval, sendo a viabilidade reduzida para 12%, com duração de 7 dias, diferindo da testemunha com 17 dias. O extrato da mesma planta a 10% causou 48% de mortalidade. Em todas as concentrações esse extrato também afetou a fase de pupa; na testemunha, 85% das pupas foram viáveis, enquanto nos demais tratamentos a viabilidade não excedeu a 25%. Para o peso e comprimento das lagartas, os resultados não foram significativos. Para o mastruz, o extrato a 20% causou influência na fase larval com baixa viabilidade e mortalidade logo nos primeiros seis dias de avaliação. Outras concentrações de mastruz não deferiram entre si nas fases larval e pupal. Verificou-se que a alimentação das lagartas com folhas tratadas com mastruz diminuiu o peso das pupas.


ABSTRACT: The effect of aqueous extracts of yam (0, 5, 10, and 20% h/h) and chenopodium (0, 2, 4, 6, 8 and 10% h/h) on the biology of fall armyworm was studied. Sections of maize leaves were dipped for 30 seconds in solutions of each concentration; after the section dried, a recently hatched caterpillar was placed onto each treated section. The viability and duration of the larval and pupal stages and the weight and length of the caterpillars and pupae were evaluated. For yam, the extract at 20% concentration caused the greatest influence on the larval stage of the insect, significantly reducing larval viability to 12%, with 7 day larval stage duration, differing from the control at 17 days. The extract of the same plant at 10% caused 48% larval mortality. At all concentrations, that extract also affected the pupal stage; in the control, pupal viability was 85%, whereas for the other concentrations the viability did not exceed 25%. No significant differences were observed for the weight and length of caterpillars. For chenopodium, the extract at 20% concentration caused influence on the larval stage, as it showed the lowest viability, causing mortality in six days. Other chenopodium concentrations did not show differences for the larval and pupal stages. Feeding caterpillars with leaves treated with the extract of chenopodium decreased pupal weight.


Assuntos
Spodoptera/crescimento & desenvolvimento , Chenopodium ambrosioides/anatomia & histologia , Colocasia/metabolismo , Controle de Pragas/métodos , Agentes de Controle Biológico/análise
6.
Rev. colomb. biotecnol ; 16(2): 129-140, jul.-dic. 2014. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-731740

RESUMO

El gusano cachón Erinnyis ello (L.) es una plaga polífaga que puede causar graves pérdidas en cultivos de caucho. El uso de granulovirus representa una alternativa interesante para el control biológico de este insecto. Tres aislamientos colombianos del granulovirus de E. ello (EeGV) recuperados en larvas de campo, fueron caracterizados morfológica y molecularmente. Los cuerpos de inclusión de los tres aislamientos presentaron forma ovoide con una única nucleocápside, con tamaño promedio de 302,9 ± 22 x 181,5 ± 16 nm. El análisis de los perfiles de restricción con diferentes endonucleasas no mostró diferencias entre los tres aislamientos, lo cual sugiere que son muestras de la misma cepa viral, denominada VG010, cuyo tamaño del genoma se estimó en 88,7 Kb. El análisis de las relaciones filogenéticas basado en las secuencias de lef-8, lef-9 y gran mostró con alta consistencia la estrecha relación entre VG010 y un aislamiento de EeGV (M34-4) previamente descrito, lo cual sugiere que son variantes genotípicas de la misma especie viral. La eficacia del aislamiento VG010 en condiciones de laboratorio sobre larvas de segundo y cuarto estadio fue de 100 % y 64 % respectivamente, mientras que la concentración letal media (CL50) fue 4,3 x 103 CI/mL. La productividad viral, osciló entre 2,1 x 109 y 3,8 x 109 CI/gramo de larva. Estos resultados representan la base para el desarrollo de un nuevo bioinsecticida para el control de la plaga en campo.


Erinnyis ello (L.) is a polyphagous lepidopteran pest that may cause serious annual losses in the rubber industry. The use of granulovirus represents an interesting alternative as a biological control agent for this insect. Three Colombian isolates of granulovirus for E. ello (EeGV) were obtained from field larvae and characterized at morphological, biological and molecular level. Occlusion bodies (OB) of the three isolates showed an oval morphology with a unique nucleocapsid, with a size of 302.9 ± 22 x 181.5 ± 16 nm. Analysis of DNA endonuclease restriction profiles did not showed differences among the three viral isolates, which means that they correspond to samples of the same viral strain, denominated VG010. The VG010 viral genome size was estimated to be approximately 88.7 kb. The analysis of the phylogenetic relationships based on selected gene sequences lef-8, lef-9 and gran showed a close relationship between VG010 and the previously described isolate EeGV (M34-4). These sequence similarities suggest that the three isolates are genotypic variants of the same viral species. The in vitro efficacy of the VG010 isolate against second and fourth instar larvae was 100 and 64%, respectively, while the mean lethal concentration (LC50) was 4,3 x 103 OB/mL. The viral productivity ranged between 2.1 x 109 and 3.8 x 109 OB/g of larvae. These results represent the basis to develop a new biopesticide control agent for the pest in the field.

7.
NOVA publ. cient ; 11(20): 87-96, jul.-dic. 2013. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: lil-729517

RESUMO

Bacillus thuringiensis es un bacilo Gram positivo que durante su fase de esporulación produce unainclusión parasporal, conformada por proteínas Cry con actividad biológica contra insectos-plaga. Gracias a estas proteínas Bacillus thuringiensis presenta toxicidad contra larvas de insectos-plaga de los órdenes Lepidóptera, Coleóptera y Díptera, entre otros. Además es amigable con el medioambiente, razones por la cuales se ha hecho común el uso y desarrollo de productos comerciales y plantas transgénicas a base de toxinas Cry en el sector agrícola. En esta revisión se describirá los aspectos más importantes de Bt y su aplicación como herramienta biotecnológica para el sector agrícola, con una consideración sobre bioensayos usando esta bacteria.


Bacillus thuringiensis (Bt) is a Gram-positive rod-shape bacterium that during its sporulation phase produces a parasporal inclusion formed by Cry proteins having biological activity against pest insects. Because of these proteins, Bt shows toxicity toward pest insect larvae of Lepidoptera, Coleoptera and Diptera orders among others, besides of friendly with the environment, and for this reason Bt has a very common use for commercial products and transgenic plants with Cry protein basis in agriculture. In this review is described the most important Bt factors and their application as biotechnological tool in agrobusiness, considering Bt bioassays.


Assuntos
Humanos , Biotecnologia , Bacillus thuringiensis , Uso de Praguicidas , Agricultura
8.
Br Biotechnol J ; 2012 Jan; 2(1): 1-12
Artigo em Inglês | IMSEAR | ID: sea-162362

RESUMO

Aims: In an attempt to explore novel agents for application in agriculture, the strain Serratia entomophila AB2 was investigated. Study design: Pesticidal, Fertilizing and Toxicological effects. Place and Duration of Study: Department of Botany (Microbiology Unit), Visva-Bharati, Santiniketan, West Bengal, India and M/S Ajay Biotech (India) Ltd., Pune, India, between December 2006 to August 2007. Methodology: Pesticidal activity of the isolate Serratia entomophila strain AB2 was tested against 5 day old larvae of Heliothis armigera, Spodoptera litura, and Plutella xylostella through feeding assay. Fertilizing capacity of the strain was determined by inorganic phosphate and zinc solubilizing experiments. Conventional T-tests were performed to check effect against certainr rhizospheric organisms (Azotobactor chroococcum NCIM 2452, Rhizobium japonicum NCIM 2746, Azospirillum brasiliensis NCIM 5135, Erwinia amylovora MDVB). In animal toxicity experiments, adult male Swiss albino mice (body wt ≈ 25 g) were used to find LD50 within the experimental doses and male Sprague Dawley strain of Swiss albino rat (body wt ≈ 110 g) were used to find out the effect of feed inoculation treatment in liver and blood as general target of intoxication through standard thiobarbituric acid reactive substance (TBARS) and serum glutamic pyruvic transaminase (SGPT) assay. Results: The mortality rate of, lepidopteron larvae tested was determined between 89.5 to 94.3% while LC50 value estimated between 0.44x105 to 1.44x105 CFU (colony forming unit) mL-1 through probit analysis. As a part of fertilizing activity, S. entomophila AB2 was found to solubilize phosphorus and zinc in in-vitro condition. In cross reactivity study with other rhizospheric bacteria, the isolate proved as non reactive. No mortality was recorded with Swiss albino mice and other toxicological data resulted from the experiment with Sprague Dawley strain of Swiss albino rat were found insignificant. Conclusion: The isolate S. entomophila AB2 showed its potential in in vitro conditions for both pesticidal and fertilizing activity. The data generated in this study show much promise of S. entomophila AB2 for its field application in integrated crop management (ICM). These predictors, however, need further work for field validation.

9.
Braz. arch. biol. technol ; 52(spe): 121-130, Nov. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-539858

RESUMO

Aedes aegypti is the vector of Dengue disease, responsible for 20,000 deaths/year worldwide. Bacillus thuringiensis var israelensis - Bti releases selective and effective toxins (crystal proteins) against A. aegypti larvae. We present a low cost bioprocess for toxin production, accomplished by a selected Brazilian strain Bti (BR-LPB01) and employment of low cost substrates. Soybean meal and sugarcane molasses lead to high toxic effectiveness after 2L bioreactor fermentation (LD50=26ng/mL), near to the reference strain IPS82 (LD50=17.3 ng/mL). The pH ranged between 5.8 and 7.0 during the exponential growth period and between 7.0 and 8.4 during the stationary phase, with low activity. Thus, control of foam and pH 7.0 were started and proved to be crucial for high activity. It was verified that the fermentation could be discontinued after 20 hours, when the highest activity was present.


A dengue é transmitida pelo Aedes aegypti, doença responsável por 20.000 mortes/ano no mundo. Bacillus thuringiensis var israelensis libera toxinas seletivas e eficazes (proteínas cristal) contra larvas de A. aegypti. Propõe-se um bioprocesso de baixo custo para a produção da toxina, pelo emprego de uma cepa brasileira selecionada de Bti (BR-LPB01) e de substratos de baixo custo. Farelo de soja e melaço de cana levaram a eficácia tóxica alta após fermentação em biorreator 2L (DL50=26ng/mL), valor próximo a estirpe de referência IPS82 (DL50=17,3 ng/mL). O pH variou entre 5,8 e 7,0 durante o período de crescimento exponencial e entre 7,0 e 8,4 durante a fase estacionária, com baixa atividade larvicida. Assim, controles de espuma e de pH 7,0 foram iniciados e demonstraram serem cruciais para alta atividade. Verificou-se que a fermentação deve ser interrompida após vinte horas, quando se obtém a maior atividade.

10.
Interciencia ; 34(2): 130-134, feb. 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-630766

RESUMO

A granular formulation of the entomopathogenic fungus Nomuraea rileyi (Farlow) Samson was evaluated against Spodoptera frugiperda (Lepidoptera: Noctuidae). The formulation consisted of 1mm particles of defatted corn germ (DCG) containing 10(7) conidia/g. This preparation protected the conidia against UV radiation and killed 80% of S. frugiperda larvae in laboratory bioassays. It was shown that the fungus used DCG as a substrate for growth and sporulation, creating foci for further infection. This strategy has great potential for the formulation of fungal biocontrol agents, especially those with a high growth rate.


Una formulación granulada del hongo entomopatógeno Nomuraea rileyi (Farlow) Samson fue evaluada contra Spodoptera frugiperda (Lepidoptera: Noctuidae). La formulación consistió de partículas de 1mm de diámetro de germen desgrasado de maíz (GDM) inoculadas con 10(7) conidias/g. La preparación protegió a las conidias de la radiación UV y eliminó al 80% de la población de larvas de S. frugiperda en bioensayos de laboratorio. Se demostró que el hongo es capaz de utilizar el GDM como un sustrato de crecimiento y esporulación creando nuevos focos de infección. Este tipo de estrategias posee gran potencial para la formulación de agentes fúngicos de biocontrol, especialmente aquellos con alta tasa de crecimiento.


Uma formulação granulada do fungo entomopatogênico Nomuraea rileyi (Farlow) Samson foi avaliada contra Spodoptera frugiperda (Lepidoptera: Noctuidae). A formulação consistiu de partículas de 1mm de diâmetro de germem desengordurado de milho (GDM) inoculadas com 10(7) conidias/g. A preparação protegeu às conídias da radiação UV e eliminou 80% da população de larvas de S. frugiperda em bioensaios de laboratório. Demonstrou-se que o fungo é capaz de utilizar o GDM como um substrato de crescimento e esporulação criando novos focos de infecção. Este tipo de estratégias possui grande potencial para a formulação de agentes fúngicos de biocontrole, especialmente aqueles com alta taxa de crescimento.

11.
Neotrop. entomol ; 32(2): 183-195, Apr.-June 2003. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-513518

RESUMO

Thousands of potential microbial biocontrol agents have been isolated from agricultural fields and crops during research over the last 80 years, yet only a few are in commercial use. Recently, public health and safety concerns about the environmental impact of chemical pesticides have led to consideration of biological control as a natural approach to maintaining crop health. Despite environmental incentives and strong research efforts, commercialization of biocontrol agents has been slow to evolve. The momentum of the chemical industry is difficult to shift, and fermentation processes tend to be more expensive to operate than synthetic chemical processes.Yet there is a demand for biological control products, especially in agricultural niche markets, where there is no chemical competitor. However, given this market demand, the fundamental methods of economical large-scale production and application of biological control agents are lacking. Many aspects of biocontrol agent production and development represent untrodden territory in the progression of industrial fermentation technology beyond its well-established food and pharmaceuticals niche. Distinguishing them from traditional fermentation products, biocontrol agents must not only be produced in high yield but must also meet the following quality criteria: high (near 100 percent) retention of cell viability with maintenance of crop compatibility and consistent bioefficacy during several months of storage. Research examples will be reviewed to illustrate the challenges and strategies of developing processes to manufacture and deliver biological agents for insect, weed, and plant disease control.


Milhares de agentes de controle microbiano potenciais têm sido isolados a partir de campos cultivados ou de culturas pelo esforço da pesquisa nos últimos 80 anos. Entretanto, apenas alguns microrganismos têm uso comercial. Recentemente, medidas de saúde pública e de segurança sobre o impacto ambiental de pesticidas químicos têm levado a se considerar o controle biológico como uma medida promissora para proteção das culturas. Apesar do incentivo ambiental e esforços de pesquisa, a evolução da comercialização dos agentes de biocontrole tem sido lenta. O "momentum" da indústria química é difícil de mudar, e processos fermentativos tendem a ser mais caros e custosos do que os processos químicos sintéticos. Mesmo assim, há demanda para produtos de controle biológico, especialmente em nichos de mercados agrícolas onde não existe um competidor químico. Entretanto, os fundamentos dos métodos econômicos de produção e aplicação dos agentes de biocontrole em larga escala não existem. Muitos aspectos do desenvolvimento e da produção de agentes de controle biológico representam uma área diferenciada na tecnologia de produção industrial por fermentação, já bem estabelecida no nicho farmacêutico e alimentar. Ao se diferenciar dos produtos fermentados tradicionais, os agentes de biocontrole necessitam atingir os critérios de alta (ca. 100 por cento) retenção da viabilidade celular e compatibilidade com a cultura e bioeficiência durante vários meses de armazenagem. Exemplos da pesquisa são discutidos exemplificando-se os desafios e as estratégias dos processo de desenvolvimento para produzir e viabilizar agentes de biocontrole de insetos, ervas-daninhas e doenças.

12.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM | ID: wpr-684071

RESUMO

Spinosyns are secondary metabolites from the aerobic fermentation of saccharopolyspora spinosa Spinosyn is a kind of broad spectrum insecticide, which has contact and ingestion toxicity on insects On lepidopteran insects, spinosad (a mixture of spinosyn A and spinosyn D) is one of the most selective compounds ever discovered In this paper, the structure, biosynthesis, property and process of spinosyns are reviewed

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