Marina Andressa Formentini

Ocorrência natural de Beauveria bassiana (Bals.) Vuill. (Moniliales: Moniliaceae) e patogenicidade sobre Protortonia navesi Fonseca (Hemiptera: Monophlebiidae) na cultura da mandioca, em Marechal Cândido Rondon, Paraná

The objective of this study was to record the first natural occurrence and pathogenicity of the association between Beauveria bassiana and Protortonia navesi in the cassava crop. Infected P. navesi nymphs and adults were collected in samples fortnightly in the Agronomic Institute of Parana, in Marechal Cândido Rondon, from January to December 2012. Samples were analyzed at the Laboratory of Agricultural Biotechnology. The entomopathogenic fungus was isolated from corpses using selective oatmeal culture medium, and multiplied for sporulation being identified as Beauveria bassiana (Bals.) Vuill. The fungus was stored in the Collection of Entomopathogenic Fungi Laboratory of Agricultural Biotechnology, identified as Unioeste 78. To prove the pathogenicity of the found isolate, bioassays were performed following the postulate of Koch, the fungi suspension was sprayed (109conidios mL), on nymphs and adults of P. navesiobtained from laboratory rearing. After 10 days of incubation there was 18% mortality confirmed, being considered low actgivity on mealybugs Protortonia.

Patogenicidade de isolados de fungos entomopatogênicos à Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)

This study aimed to evaluate the pathogenicity, under laboratory conditions, of 49 isolates of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae against Spodoptera frugiperda larvae. Insects (3rd instar caterpillars) were immersed in 1 × 109 conidia/mL suspensions of each of the isolates for 10 seconds. After that, caterpillars were individually placed in Petri dishes with artificial diet and incubated at 26 ± 1°C and 12 hours of photophase, and they were evaluated daily for ten days. The B. bassiana isolates were more efficient, mainly Unioeste 26 strain, which reached 44.5% mortality and generated the greatest number of conidia in production testing of the fungus. Despite the low mortality percentage, these studies showed the potential of entomopathogenic fungi as promising agents for the control of S. frugiperda.