Divulgação3006Prelecionista: Mateus Durso Martins; Data: 30/6/2022, às 14h, via Zoom*; Orientador: Gleiber Quintão Furtado

Resumo: Brazil is the global leader of forest productivity and approximately 78% of the planted area is occupied with eucalypt plantations. For the first time, a fungus that resembles Chrysoporthe sp. was found associated with eucalypt mini-stumps in mini-clonal gardens in Brazil causing severe losses. The symptoms observed were wilt that evolves into partial or complete drying and death of the canopy, and discoloration of the xylem of the mini-stumps. The aims of the present study were (i) to elucidate the etiology of wilt disease on eucalypt mini-stumps through morphological/molecular analyses; (ii) to evaluate the pathogenicity of the isolates to different commercial clones of eucalypt; and (iii) to evaluate the influence of temperature on the development of the pathogen. Phylogenetic analyses of genes actin and β-tubulin confirmed Chrysoporthe cubensis as the causal agent of the wilt. All of the six eucalypt commercial clones tested were susceptible to the pathogen. The clone CNB 007 was more susceptible and clones CNB 030 and CNB 032 were less susceptible. It was observed that the isolates developed differently depending on the eucalypt clone. Both clones were more susceptible to the pathogen at 28oC than at 19oC. Besides, the less susceptible clones were more influenced by higher temperatures than more susceptible clones. This is the first report of C. cubensis causing wilt on eucalypt mini-stumps worldwide. 

*Interessados, solicitar acesso pelo e-mail pos.fitopatologia@ufv.br.