First Report of Rattail Cactus Necrosis-Associated Virus (Tobamovirus muricaudae) in Symptomless Opuntia leucotricha in Brazil

Author(s)

Guimaraes, Jandson Jose do Vale ; Del Corona, Fernanda de Padua ; Bello, Vinicius Henrique ; Ramos-Gonzalez, Pedro Luis ; Lorenzi, Harri ; Kitajima, Elliot Watanabe

• Document type: Journal article
• Source: JOURNAL OF PHYTOPATHOLOGY; v. 173, n. 2, p. 3-pg., 2025-03-01.

Abstract

In 2024, a tobamovirus was found in a symptomless prickly pear (Opuntia leucotricha) plant in Brazil. Transmission electron microscopy examinations revealed tobamovirus-like particles ca. 300 nm long in negatively stained cladode's extracts from an asymptomatic O. leucotricha plant. High-throughput sequencing resulted in a 6374 nucleotide contig that shares 98.68% nucleotide sequence identity with rattail cactus necrosis-associated virus (RCNaV, Tobamovirus muricaudae), first detected in Aporocactus flagelliform, in South Korea. The near-complete genome of the RCNaV_BR1 isolate has the canonical genomic organisation of viruses in the genus Tobamovirus. The viral infection in the cactus was validated by RT-PCR using RCNaV_BR1-specific primers followed by Sanger sequencing. The RCNaV_BR1 could be mechanically transmitted to the experimental hosts Chenopodium amaranticolor, C. quinoa and Datura stramonium, and by grafting to some cactus plants (dragon fruit-Selenicereus spp., Opuntia brasiliensis, Epiphyllum sp.), which remained symptomless. This is the first report of RCNaV infecting any cactaceae in Brazil. (AU)

• FAPESP's process: 24/06440-7 - Survey of plant viruses and viroids in Brazil, with emphasis on those infecting cactaceas, and the continuation on the organization of the list of plant viruses and viroids described in Brazil, after 2018. Phase IV
• Grantee: Elliot Watanabe Kitajima
• Support Opportunities: Regular Research Grants