Fungos entomopatogênicos em solo com plantio de eucalipto

Abstract

Among the biological control agents, entomopathogenic fungi can control infestations of insects that harm production in the forest sector and these fungi can be found in different types of soil. To identify entomopathogenic fungi in areas of planted forests, this study aimed to identify morphologically and molecularly, entomopathogenic soil fungi of eucalyptus plantations. For this, soil samples were collected from ten properties in the cities of Ampere and Dois Vizinhos, both in the state of Parana. In each property were removed five soil samples, each of these samples was composed of two subsamples of one gram each. In laboratory these sub-samples were diluted three times, up to 10-². The last dilution was used to prepare bioassays, and each subsample was three replicates. The bioassay was prepared using culture media like PDA (potato, dextrose and agar). Bioassays were placed in B.O.D. (27 ± 2 ° C, 70 ± 10% RH and 12 hours fotofase), after seven days, the fungi were identified microscopically and scraped to this, a drop of methylene blue dye was placed, with a pipette on a microscope slide for spreading the fungus in liquid with of a platinum needle, and covering the material with cover slip. The material was observed under light microscope (Alltion, objective 640) and analyzed with the material described in Alves, 1998, ch. Entomopathogen characterization. Later these fungi were subjected to molecular analysis by PCR-ISSR technique, with primers 5'BDB (ACA) 5, 5'DD (CCA) and 5 5'VHV (TGT) 5. And so it was possible to perform electrophoresis to verify the amplification of the DNA of the entomopathogenic fungi. From microscopic analysis verified the presence of entomopathogenic fungi, which are derived from properties 1, 2, 4, 6, 7 and 10. All properties 1 and 2, both located in the city of Ampere-PR was identified morphologically, the M. anisopliae species being found one isolated each property. In the properties of 4, 6 and 7 was identified species B. bassiana, the property having one isolated 4, two isolates in property 6 and also two isolated in property 7. The species of entomopathogenic fungus Isaria fumosorosea was found in two strains of ownership 10, in the city of Dois Vizinhos-PR. The molecular characterization of entomopathogenic fungi showed the similarity between individuals of different species, we can point out that there have been sampled individuals. Existing diversity of entomopathogenic species in soils with eucalyptus, will be good for one's own culture. For thus pest species may be controlled by the fungi that are naturally present in soil culture itself.