Sensibilidade de fungos entomopatogênicos a agroquímicos usados no manejo da cana-de-açúcar
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Data
2011-01-01
Autores
Botelho, Aline Aparecida Alves [UNESP]
Monteiro, Antonio Carlos [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Instituto Agronômico de Campinas
Resumo
Os agroquímicos empregados no manejo da cana-de-açúcar podem afetar a ação de fungos entomopatogênicos usados no controle biológico de pragas da cultura. Este trabalho teve por objetivo investigar se os inseticidas, herbicidas e maturadores utilizados no manejo da cana-de-açúcar têm efeito tóxico sobre os fungos Beauveria bassiana e Metarhizium anisopliae. Foram utilizados os inseticidas thiametoxan, aldicarbe e fipronil, os herbicidas imazapir, diuron, metribuzin, hexazinone+diuron, clomazone+ametrina, 2,4 diclorofenoxiacético e glifosato, e os maturadores etil-trinexapac, sulfometurom-metílico e glifosato também. Os fungos foram cultivados em meio de cultura batata-dextrose-ágar contendo os agroquímicos. Avaliou-se o crescimento micelial, a produção e viabilidade dos conídios, e fez-se a avaliação da toxicidade dos agroquímicos. O inseticida à base de thiametoxan foi considerado compatível, pois não afetou o crescimento micelial, a produção e a viabilidade dos conídios dos dois fungos. O inseticida formulado com fipronil se mostrou parcialmente tóxico para os fungos, sendo considerado moderadamente compatível, enquanto o aldicarbe foi considerado tóxico. Os herbicidas avaliados afetaram o crescimento micelial, a produção e a viabilidade dos conídios dos entomopatógenos e foram classificados como tóxicos, mas aqueles formulados com imazapir, glifosato e metribuzim foram considerados compatíveis. Entre os agroquímicos usados como maturadores apenas o glifosato foi classificado como compatível. Os agroquímicos usados no manejo da cana-de-açúcar, e que foram testados neste estudo, têm majoritariamente efeito tóxico sobre B. bassiana e M. anisopliae podendo comprometer sua ação como bioagentes de controle de pragas da cultura.
The pesticides used in management of sugarcane can affect the action of entomopathogenic fungi used for biological control of pests. The objective of this work was to investigate if the insecticides, herbicides and ripeners used in management of sugarcane have toxic effect on the fungi Beauveria bassiana and Metarhizium anisopliae. The insecticides used were thiamethoxan, aldicarb and fipronil, the herbicides imazapyr, diuron, metribuzin, hexazinone+diuron, clomazone+ametryn, 2,4 dichlorophenoxyacetic and glyphosate, the ripeners ethyl-trinexapac, sulfometuron-methyl and also glyphosate. The fungi were grown in potato dextrose agar medium containing chemical pesticide. Micelial growth, production and viability of conidia were evaluated, as well as the toxicity of the chemical pesticides. The thiamethoxan insecticide was considered compatible, because it did not affect the micelial growth, production and conidial viability of both fungi. The fipronil insecticide was partially toxic to the fungi, being considered moderately compatible, whereas aldicarb was considered toxic. Most of the evaluated herbicides affected the growth, production and conidial viability of both entomophatogenic fungi and were classified as toxic, but those formulated with imazapyr, glyphosate and metribuzin were considered compatible. Among the ripeners analyzed only glyphosate was classified as compatible. The chemical pesticides used in management of sugarcane and evaluated in this work have toxic effect on the fungi B. bassiana and M. anisopliae, which can compromise its action as bioagents of pest control.
The pesticides used in management of sugarcane can affect the action of entomopathogenic fungi used for biological control of pests. The objective of this work was to investigate if the insecticides, herbicides and ripeners used in management of sugarcane have toxic effect on the fungi Beauveria bassiana and Metarhizium anisopliae. The insecticides used were thiamethoxan, aldicarb and fipronil, the herbicides imazapyr, diuron, metribuzin, hexazinone+diuron, clomazone+ametryn, 2,4 dichlorophenoxyacetic and glyphosate, the ripeners ethyl-trinexapac, sulfometuron-methyl and also glyphosate. The fungi were grown in potato dextrose agar medium containing chemical pesticide. Micelial growth, production and viability of conidia were evaluated, as well as the toxicity of the chemical pesticides. The thiamethoxan insecticide was considered compatible, because it did not affect the micelial growth, production and conidial viability of both fungi. The fipronil insecticide was partially toxic to the fungi, being considered moderately compatible, whereas aldicarb was considered toxic. Most of the evaluated herbicides affected the growth, production and conidial viability of both entomophatogenic fungi and were classified as toxic, but those formulated with imazapyr, glyphosate and metribuzin were considered compatible. Among the ripeners analyzed only glyphosate was classified as compatible. The chemical pesticides used in management of sugarcane and evaluated in this work have toxic effect on the fungi B. bassiana and M. anisopliae, which can compromise its action as bioagents of pest control.
Descrição
Palavras-chave
biocontrol, Beauveria bassiana, Metarhizium anisopliae, Saccharum sp, compatibility, Toxicity, Controle biológico, Beauveria bassiana, Metarhizium anisopliae, Saccharum sp., Compatibilidade, Toxicidade
Como citar
Bragantia. Instituto Agronômico de Campinas, v. 70, n. 2, p. 361-369, 2011.