Etiologia, patogenicidade e transmissão de fungos associados às plantas do cerrado e suas sementes

Abstract

Etiology, pathogenicity and transmission of fungi associated with Cerrado plants seeds. Although the presence of fungi associated with the seeds of forest species can cause damage to the producers and damages to the plants, there are still few studies developed for many species of plants that depend on the seeds to multiply. Thus, the objective of this work was to evaluate the physiological and sanitary quality of seeds of Cerrado forest species as well as to identify the fungi associated with these seeds, evaluating their pathogenicity, transmission, etiology and occurrence in their natural environment, in seven forest species: Senegalia polyphylla, Parkia pendula, Terminalia argentea, Jacaranda brasiliana, Astronium fraxinifolium, Tabebuia impetiginosa and Apeiba tibourbou. Initially, among the species studied with germination problems, four of them were submitted to dormancy. After that, all seeds were submitted to germination test, seedling emergence, seed health evaluation, seed-seedling transmission test, identification and pathogenicity of fungi associated with seeds. According to the results, it was verified a higher percentage of seed germination and emergence in the Parkia pendula species. In the seed sanity test, it was verified that asepsis had a positive influence on the variation of fungi incidence in forest seeds. In relation to the transmission of fungi of the forest species analyzed, it was observed that the genera Curvularia, Fusarium and Colletotrichum presented the highest percentage of seed transmission to the seedlings. Among the fungi, isolates of Curvularia sp. potentially pathogenic to the Senegalia polyphylla forest species. The genus Fusarium sp. was pathogenic to forest specie Astronium fraxinifolium.