PATOGENICIDADE E TRANSMISSÃO DE FUNGOS ASSOCIADOS ÀS SEMENTES DE Tectona grandis L.f.

Abstract

The production of teak seedlings is mainly carried out by seeds, which is an important vehicle for the transmission of various pathogens. The purpose of this study was to identify and quantify the fungi associated with teak seeds, the pathogenicity of these microrganisms to the seedlings and the seed-seedling transmission. There were used seeds collected in Tocantins state and others acquired in the states of Goias (GO) and in São Paulo (SP) for the sanity test. The treatments used were seeds disinfested and not disinfested, and seeds with and without mesocarp. The analysis was conducted using the paper filter method (Blotter test). To pathogenicity test in seedlings, were utilized the isolates of Fusarium sp., Botryodiplodia sp., Alternaria sp. and Plenodomus sp. To evaluate the fungal seedling-transmission were used seeds of each location.The following genera of fungi were identified in the seeds: Fusarium, Trichoderma, Botryodiplodia, Aspergillus, Penicillium, Rhizopus, Cladosporium, Alternaria and Plenodomus. A higher occurrence of fungi was observed in the seeds from the states of GO and SP. Fusarium was the fungal genera with the highest incidence in the seeds of the three states. Only the Fusarium and Botryodiplodia genera were pathogenic to teak seedlings. There was low seed-seedling transmission, with only the phytopathogenic genus Fusarium being transmitted.