Fusarium oxysporum and Fusarium solani inoculation and shading levels in the erva-mate: severity influence of the root-rot

A erva-mate ( Ilex paraguariensis A. St.-Hill) \ue9 uma esp\ue9cie amplamente cultivada na Regi\ue3o Sul do Brasil. Com o aumento da \ue1rea plantada, sobretudo na \ufaltima d\ue9cada, os problemas fitossanit\ue1rios causados por pragas e doen\ue7as aumentaram e, dentre estes, a podrid\ue3o-de-ra\uedzes vem se tornando um dos principais. Dentre os pat\uf3genos causadores dessa doen\ue7a, Fusarium oxysporum Schlecht. e Fusarium solani (Mart.) Sacc s\ue3o os principais. Esses fungos provocam s\ue9rios danos decorrentes da destrui\ue7\ue3o do sistema radicular, ocasionando, nos casos mais graves, a morte da planta. Suspeita-se que a incid\ueancia e a severidade da doen\ue7a s\ue3o influenciadas pelo cultivo de ervais em diferentes n\uedveis de sombreamento ou a pleno sol. Assim, foram instalados experimentos na \ue1rea do Viveiro Florestal pertencente ao Departamento de Ci\ueancias Florestais/CCR/UFSM com o objetivo de confirmar tal hip\uf3tese. O experimento foi conduzido em um esquema fatorial (2 x 5), composto pela inocula\ue7\ue3o de Fusarium oxysporum e Fusarium solani e por n\uedveis de sombreamento. Verificou-se que as plantas submetidas aos menores n\uedveis de sombreamento ou a pleno sol ficaram predispostas \ue0 doen\ue7a.Ilex paraguariensis A. St.-Hill is a broadly cultivated species in the South of Brazil. With the increasing planted area, mainly in the last decade, fitosanitary problems caused by pest and diseases have increased in this crop, and the root-rot is becoming one of the main problems. Among the pathogens, Fusarium oxysporum Schlecht. and Fusarium solani (Mart.) Sacc are the main ones. These fungi provoke severe damages resulting in the destruction of the root system and, in the most serious cases, they cause the death of the plant. It is suspected that the incidence and severity of disease are influenced by cultivation of Ilex paraguariensis in different levels of shading or full sun. Therefore, experiments were conducted in the Forest Nursery area belonging to Forest Sciences Department/CCR/UFSM with the objective of confirming this assumption. The experiment was conducted in a factorial design (2 x 5), composed by Fusarium oxysporum and Fusarium solani inoculation and by shading levels. It was verified that the plants submitted to lower shading levels or full sun had their predisposed to the disease