RESUMO
This study was carried out to select isolates of the entomopathogenic fungus Beauveria bassiana with pathogenic potential to control the Rhipicephalus (Boophilus) microplus tick. The effectiveness of thirty isolates was first tested at a concentration of 5 x 108 conidia.mL(-1). Of these, eight were evaluated (IBCB01, IBCB02, IBCB07, IBCB17, IBCB21, IBCB74, IBCB149, IBCB165) and showed an effectiveness between 90 and 99%; thirteen (IBCB03, IBCB14, IBCB16, IBCB24, IBCB95, IBCB97, IBCB102, IBCB141, IBCB146, IBCB147, IBCB150, IBCB154, IBCB157) between 80 and 89,5%; six (IBCB47, IBCB75, IBCB84, IBCB145, IBCB161, IBCB164) between 70 and 79%, and only two (IBCB13 and IBCB143) had lower pathogenicity (70% or below). In the second step of the study, the five more effective strains in the first phase of the experiment (IBCB01, IBCB07, IBCB21, IBCB66, IBCB165) were analyzed comparatively. Based on in vitro results, it can be concluded that IBCB66 and IBCB21 are the isolates with higher potential for field control of R. (B.) microplus. IBCB01, IBCB07, IBCB21, IBCB66 e IBCB165 isolates were submitted to a conidial production test using a rice-based substrate. The best mass production of the entomopathogenic fungus was obtained with the IBCB66 strain.
Assuntos
Ascomicetos/isolamento & purificação , Beauveria/isolamento & purificação , Ixodidae , Controle Biológico de Vetores , Animais , Ascomicetos/fisiologia , Beauveria/fisiologiaRESUMO
O presente estudo foi conduzido com o objetivo de selecionar isolados do fungo entomopatogênico Beauveria bassiana com potencial patogênico para utilização no controle do carrapato Rhipicephalus (Boophilus) microplus. Numa primeira etapa, foi avaliada a eficiência de trinta isolados na concentração de 5 × 10(8) conídios.mL-1. Destes, oito (IBCB01, IBCB02, IBCB07, IBCB17, IBCB21, IBCB74, IBCB149, IBCB165) apresentaram eficiência entre 90 e 99%; treze (IBCB03, IBCB14, IBCB16, IBCB24, IBCB95, IBCB97, IBCB102, IBCB141, IBCB146, IBCB147, IBCB150, IBCB154, IBCB157), indicaram percentuais de eficiência entre 80 e 89,5%; seis (IBCB47, IBCB75, IBCB84, IBCB145, IBCB161, IBCB164), entre 70 e 79% e apenas dois, (IBCB13 e IBCB143) revelaram-se pouco virulentos com porcentagens abaixo de 70%. Na segunda etapa do trabalho, foram analisados comparativamente dados de mortalidade acumulada dos cinco melhores isolados obtidos na primeira fase (IBCB01, IBCB07, IBCB21, IBCB66, IBCB165). Analisando-se os resultados obtidos in vitro, pode-se imputar que os isolados IBCB21 e IBCB66 são os que apresentam maior potencial para utilização a campo, tendo em vista o controle de R. (B.) microplus. Os isolados selecionados, na primeira fase, também foram testados quanto à potencialidade de produção massal em meio de arroz pré-cozido. A melhor produção massal foi obtida com o isolado IBCB66.
This study was carried out to select isolates of the entomopathogenic fungus Beauveria bassiana with pathogenic potential to control the Rhipicephalus (Boophilus) microplus tick. The effectiveness of thirty isolates was first tested at a concentration of 5 × 10(8) conidia.mL-1. Of these, eight were evaluated (IBCB01, IBCB02, IBCB07, IBCB17, IBCB21, IBCB74, IBCB149, IBCB165) and showed an effectiveness between 90 and 99%; thirteen (IBCB03, IBCB14, IBCB16, IBCB24, IBCB95, IBCB97, IBCB102, IBCB141, IBCB146, IBCB147, IBCB150, IBCB154, IBCB157) between 80 and 89,5%; six (IBCB47, IBCB75, IBCB84, IBCB145, IBCB161, IBCB164) between 70 and 79%, and only two (IBCB13 and IBCB143) had lower pathogenicity (70% or below). In the second step of the study, the five more effective strains in the first phase of the experiment (IBCB01, IBCB07, IBCB21, IBCB66, IBCB165) were analyzed comparatively. Based on in vitro results, it can be concluded that IBCB66 and IBCB21 are the isolates with higher potential for field control of R. (B.) microplus. IBCB01, IBCB07, IBCB21, IBCB66 e IBCB165 isolates were submitted to a conidial production test using a rice-based substrate. The best mass production of the entomopathogenic fungus was obtained with the IBCB66 strain.
Assuntos
Animais , Ascomicetos/isolamento & purificação , Beauveria/isolamento & purificação , Ixodidae , Controle Biológico de Vetores , Ascomicetos/fisiologia , Beauveria/fisiologiaRESUMO
O presente estudo foi conduzido com o objetivo de selecionar isolados do fungo entomopatogênico Beauveriabassiana com potencial patogênico para utilização no controle do carrapato Rhipicephalus (Boophilus) microplus.Numa primeira etapa, foi avaliada a eficiência de trinta isolados na concentração de 5 × 10 elevado a 8 conídios.mL elevado a 1. Destes,oito (IBCB01, IBCB02, IBCB07, IBCB17, IBCB21, IBCB74, IBCB149, IBCB165) apresentaram eficiência entre90 e 99%; treze (IBCB03, IBCB14, IBCB16, IBCB24, IBCB95, IBCB97, IBCB102, IBCB141, IBCB146, IBCB147,IBCB150, IBCB154, IBCB157), indicaram percentuais de eficiência entre 80 e 89,5%; seis (IBCB47, IBCB75,IBCB84, IBCB145, IBCB161, IBCB164), entre 70 e 79% e apenas dois, (IBCB13 e IBCB143) revelaram-se poucovirulentos com porcentagens abaixo de 70%. Na segunda etapa do trabalho, foram analisados comparativamente dadosde mortalidade acumulada dos cinco melhores isolados obtidos na primeira fase (IBCB01, IBCB07, IBCB21, IBCB66,IBCB165). Analisando-se os resultados obtidos in vitro, pode-se imputar que os isolados IBCB21 e IBCB66 são osque apresentam maior potencial para utilização a campo, tendo em vista o controle de R. (B.) microplus. Os isoladosselecionados, na primeira fase, também foram testados quanto à potencialidade de produção massal em meio de arrozpré-cozido. A melhor produção massal foi obtida com o isolado IBCB66. (AU)
This study was carried out to select isolates of the entomopathogenic fungus Beauveria bassiana with pathogenic potential to control the Rhipicephalus (Boophilus) microplus tick. The efectiveness of thirty isolates was irst tested at a concentration of 5 × 10 potentiation 8 conidia.mL potentiation -1. Of these, eight were evaluated (IBCB01, IBCB02, IBCB07, IBCB17, IBCB21, IBCB74, IBCB149, IBCB165) and showed an efectiveness between 90 and 99%; thirteen (IBCB03, IBCB14, IBCB16, IBCB24, IBCB95, IBCB97, IBCB102, IBCB141, IBCB146, IBCB147, IBCB150, IBCB154, IBCB157) between 80 and 89,5%; six (IBCB47, IBCB75, IBCB84, IBCB145, IBCB161, IBCB164) between 70 and 79%, and only two (IBCB13 and IBCB143) had lower pathogenicity (70% or below). In the second step of the study, the five more efective strains in the irst phase of the experiment (IBCB01, IBCB07, IBCB21, IBCB66, IBCB165) were analyzed comparatively. Based on in vitro results, it can be concluded that IBCB66 and IBCB21 are the isolates with higher potential for ield control of R. (B.) microplus. IBCB01, IBCB07, IBCB21, IBCB66 e IBCB165 isolates were submitted to a conidial production test using a rice-based substrate. he best mass production of the entomopathogenic fungus was obtained with the IBCB66 strain.(AU)