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

Abstract

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.

Lack of an Intron in Cytochrome b and Overexpression of Sterol 14α-Demethylase Indicate a Potential Risk for QoI and DMI Resistance Development in Neophysopella spp. on Grapes

“…AGLR symptoms occur predominantly on mature leaves, causing reduction in photosynthetic efficiency, leaf necrosis, and premature defoliation, leading to a reduction in carbohydrate accumulation in roots (Nogueira J unior et al 2017). These alterations in energy metabolism result in fruit yield and quality losses and reduced vine vigor in the subsequent seasons (Edwards 2015;Nogueira J unior et al 2017;Scapin-Buffara et al 2018). In Brazil, AGLR is caused by two biotrophic basidiomycetes, N. tropicalis in the Central-South region and N. meliosmae-myrianthae in the Northeast region (Santos et al 2021), although five Neophysopella species have been associated with grapevine leaf rust in other countries (Okane and Ono 2018;Pota et al 2015).…”

Progresso da ferrugem da videira (>i<Neophysopella tropicalis>/i<) em \'Niagara Rosada\' sob diferentes condições ambientais

“…Apesar do desenvolvimento da ferrugem não ter sido afetado pelos sistemas de condução e pela cobertura plástica, esses sistemas tiveram um impacto significativo no desenvolvimento de outras importantes doenças da videira (ALMANÇA et al, 2017;DE BEM et al, 2016, 2017SCAPIN-BUFFARA et al, 2018). Em comparação com o YT, plantas conduzidas em VSP apresentaram menor AUDPC e menores taxas de progresso de incidência e severidade de míldio (Plasmopara viticola) e podridãocinzenta da uva (Botrytis cinerea) (DE BEM et al, 2017).…”

“…Em regiões subtropicais e tropicais, a doença pode ocorrer durante todo o ciclo produtivo, ao contrário de regiões de clima mais ameno em que a doença é vista comumente ao final do ciclo da cultura (SCAPIN-BUFFARA et al, 2018).…”

“…Quando as pústulas estão densamente agregadas, o tecido foliar entre as lesões coalesce, tornando-se seco e necrótico (PRIMIANO et al, 2019). Folhas com alta severidade da doença caem prematuramente, prejudicando o acúmulo de carboidratos nas raízes (ANGELOTTI et al 2008a;SCAPIN-BUFFARA et al, 2018). A maioria das cultivares de V. vinifera e V. labrusca, incluindo 'Niagara Rosada', são suscetíveis ao patógeno (ANGELOTTI et al, 2008a;.…”

“…Batista et al (2015) eScapin-Buffara et al (2018) confirmam que o comportamento epidemiológico da ferrugem pode variar de ano para ano ou de uma estação para outra. De fato, a severidade da ferrugem foi menor na safra de outono-inverno de 2018.…”