Identification and pathogenicity ofNeophysopellaspecies associated with Asian grapevine leaf rust in Brazil

Author(s)

Santos, Ricardo F. ^[1] ; Primiano, V, Isabela ; Amorim, Lilian ^[2]

Affiliation

^[1] Univ Sao Paulo, Luiz de Queiroz Coll Agr ESALQ, Dept Plant Pathol & Nematol, BR-13418900 Piracicaba, SP - Brazil

^[2] Primiano, Isabela, V, Univ Sao Paulo, Luiz de Queiroz Coll Agr ESALQ, Dept Plant Pathol & Nematol, BR-13418900 Piracicaba, SP - Brazil

• Document type: Journal article
• Source: PLANT PATHOLOGY; v. 70, n. 1, p. 74-86, JAN 2021.
• Web of Science Citations: 0

Abstract

Asian grapevine leaf rust (AGLR) causes severe crop losses in Brazilian viticulture, mainly in latitudes <25 degrees S. The purpose of this study was to identify the pathogen(s) involved with AGLR in Brazil, based on phylogenetic and morphological analysis and pathogenicity tests. In total, 56 monouredinial isolates from six Brazilian states were identified using the internal transcribed spacer 2 and the large subunit rRNA gene D1/D2 regions. All 50 isolates from the south-central region were classified asNeophysopella tropicalis, and the other six isolates from the north-east region asNeophysopella meliosmae-myrianthae. This result provides evidence that two pathogen introductions from different sources may have occurred in the country. For both species, paraphyses were cylindrical, incurved, aseptate, and hyaline, while urediniospores were short-pedicellate, obovoid or obovoid-ellipsoid, with the wall colourless or pale yellowish, evenly echinulate. Representative isolates from both species caused typical AGLR symptoms onVitis vinifera'Merlot' andV.labrusca'Niagara Rosada'. Overall, regardless of theNeophysopellaspecies, isolates caused similar leaf disease severities. Higher disease severity was observed in Niagara Rosada (average of 40.3% of diseased leaf area) compared to Merlot (20.5%). This study reports, for the first time, the characterization ofNeophysopellaspecies associated with AGLR in Brazil. (AU)

• FAPESP's process: 15/26108-8 - Aggressiveness of Phakopsora: a comparative analysis of grapevine and soybean rusts with emphasis to histopathology and epidemiology
• Grantee: Isabela Vescove Primiano
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 13/24003-9 - Grape diseases: epidemiology, damage assessment and control
• Grantee: Lilian Amorim
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/21412-6 - Population structure and sensitivity of Plasmopara viticola and Phakopsora euvitis to fungicides in Brazil
• Grantee: Ricardo Feliciano dos Santos
• Support Opportunities: Scholarships in Brazil - Post-Doctoral