Preservation of the urediniospores of Phakopsora euvitis, the causal agent of grape leaf rust

Autor(es)

Alves, Renan Fernandes ^[1] ; Massola Junior, Nelson Sidnei ^[1] ; Sposito, Marcel Bellato ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Fitopatol & Nematol, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: European Journal of Plant Pathology; v. 150, n. 4, p. 1103-1106, APR 2018.
• Citações Web of Science: 0

Resumo

Grape leaf rust, caused by Phakopsora euvitis, is an important disease causing considerable damage to vineyards in tropical regions. This study compared different temperatures and dormancy-reversion procedures for the preservation of P. euvitis urediniospores. Urediniospores from inoculated Vitis labrusca cv. Niagara Rosada vine leaves were collected, dehydrated, and compared with non-dehydrated leaves. Both groups of urediniospores were stored at -80 A degrees C, -20 A degrees C, 5 A degrees C, and 25 A degrees C. Urediniospore viability was evaluated by in vitro germination, whereas the severity of grape leaf rust was assessed by inoculation on leaves of `Niagara Rosada' potted plants, performed immediately prior to storage and after 15, 30, 60, 90, 120 and 150 days. The viability of non-dehydrated urediniospores stored at 25 A degrees C was low, while dehydrated urediniospores retained viability up to day 30. Dehydrated urediniospores stored at -80 A degrees C had the best viability values during the 150-day experimental period. Independently of storage conditions, urediniospores germinated in vitro induced symptoms of disease in vine leaves. The severity of the disease had a strong positive correlation with the percentage of preserved urediniospores that germinated (r = 0.88). Combining dehydration and storage at low temperatures is essential to maintain the viability of urediniospores for at least 150 days. (AU)

• Processo FAPESP: 13/24003-9 - Epidemiologia, avaliação de danos e controle de doenças da videira
• Beneficiário: Lilian Amorim
• Modalidade de apoio: Auxílio à Pesquisa - Temático