Seasonal progression of leaf rust in Niagara Rosada grapevine in a biannual crop system in Brazil.

• Autor(a) principal: SCAPIN-BUFFARA, C. R.
• Data de Publicação: 2018
• Outros Autores: ANGELOTTI, F., DUFAULT, N. S., PEREIRA, C. B., TESSMANN, D. J.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Texto Completo: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1106322
• topic: Ferrugem da folha; Phakopsora euvitis; Niagara Rosada; Uva; Doença; Viticultura; Doença Fúngica; Vitis; Fungal diseases of plants

Grapevine leaf rust, which is caused by the fungus Phakopsora euvitis, is an important late-season disease of ?Niagara Rosada? (Vitis labrusca) grapevine in Brazil. The early defoliation of plants caused by the disease impairs fruit ripening and reduces marketable yield. In a study carried out in northern Paraná State, the temporal progression of grapevine leaf rust was quantified in a production system of ?Niagara Rosada? grapevine with two growing seasons per year: mid-summerautumn and late winter-spring. The influence of weather-related variables on rust progression was examined through correlation analyses. It was observed that the rust was more severe in summer-autumn than in winter-spring. Significant positive linear correlations (P ≤ 0.05) were found between rust severity and rainfall (r ≥ 0.90) and average daily hours of leaf wetness (r ≥ 0.82). In addition, negative correlation was found between rust severity and temperature (r≥ −0.84) in the mid-summer/autumn season. Mild temperatures in autumn were considered decisive for rust progression. In Brazilian tropical viticulture, management strategies for grapevine leaf rust must consider the risk of rust damage in autumn caused by temperature.