| Autor: |
de Oliveira, Charles Martins, Leite, Luís Garrigós, Vieira, Eduardo Alano, de Freitas Fialho, Josefino, Frizzas, Marina Regina, Lopes, Rogerio Biaggioni |
| Předmět: |
|
| Zdroj: |
Biocontrol Science & Technology; Aug2022, Vol. 32 Issue 8, p989-1001, 13p |
| Abstrakt: |
Eubulus cf. elongatus was recently recorded as one of the most destructive pests of cassava in the Brazilian Cerrado. In this study, we evaluate the susceptibility of E. cf. elongatus to entomopathogenic fungi and nematodes in laboratory. Adults and larvae of E. cf. elongatus were first collected in the field to assess the natural occurrence of fungi and nematodes. Seven nematode species within Heterorhabditis and Steinernema genera were tested in direct applications onto the larvae or indirectly through soil inoculation (2000 infective juveniles per group of 10 larvae). Bioassays with 16 strains of entomopathogenic fungi (beauveria and metarhizium species) were conducted by immersion (108 conidia per mL), direct spray or by exposing adults to soil sprayed with conidial suspensions (6 × 104 conidia per cm2). In all bioassays insects were kept at 24–25 °C and 75-90% RH for 16 days. Nematodes were not found naturally occurring in E. cf. elongatus larvae collected in field. Of the adults collected, 1.76% and 0.04% were infected with B. bassiana and Metarhizium sp., respectively. In the laboratory trials, the highest mortality of larvae was caused by H. bacteriophora (95.0% for application on larvae and 60% for soil application). Entomopathogenic fungi caused low mortality rates in adults of E. cf. elongatus, being less than 11% in direct and soil applications and reaching a maximum of 16.07% when insects were treated by immersion. Our results show the potential of nematodes, such as H. bacteriophora, in controlling the larvae of E. cf. elongatus in soil. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
