Autoria: BILENKI JUNIOR, V.; RODRIGUES, P. C. dos S.; AUER, C. G.; TESSMANN, D. J.; JAREK, T. M.; SANTOS, Á. F. dos

Resumo: Yerba mate (Ilex paraguariensis [St. Hil.]) is one of the main non-timber forest products in the southern region of Brazil, playinga role of great social, economic and environmental importance. Commercial yerba mate consists of leaves and young branchesof the plant, traditionally consumed as tea and chimarrão. Its extract is also used in food, cosmetics and cleaning products. In2021 and 2022, shoot blight was observed in seedlings and adult plants of yerba mate in Paraná and Rio Grande do Sul states,Brazil. The disease is characterised by dark-coloured necrotic lesions, which begin at the tip of the shoots and, in some cases,progress downwards along the shoot, causing its death. The objective of this work was to elucidate the aetiology of this disease.The causal agents of the disease were isolated from symptomatic shoots of yerba mate, and the isolates obtained were character-ised using morphology and multilocus molecular phylogeny (RNA polymerase II subunit, elongation factor 1- ? and ?-tubulingenes). Inoculation was carried out on detached leaves and shoots, under controlled conditions and on adult plants in the field.The isolates obtained proved pathogenic when inoculated, causing symptoms similar to those observed in the field. The mul-tilocus molecular phylogeny identified two species: Fusarium guttiforme and F. mexicanum, with F. mexicanum being the mostaggressive in pathogenicity tests. Fusarium cultures were reisolated, fulfilling Koch's postulates. This study represents the firstreport of F. guttiforme and F. mexicanum as causal agents of yerba mate shoot blight.

Ano de publicação: 2025

Tipo de publicação: Artigo de periódico

Unidade: Embrapa Florestas

Palavras-chave: Doença Fúngica, Doença de Planta, Etiologia, Etiology, Forest products, Fungal diseases of plants, Ilex Paraguariensis, Produto Florestal