Detection, identification and molecular analysis of viruses present in pitaya plants in Brazil

The cultivation of pitaya has been recently established in several regions of the world, there is a lack of information on its management, especially regarding the control of diseases and pests. In places where pitaya is grown around the world, symptoms such as mosaic and mottling caused by simple or mixed viral infections have been reported. In Brazil, similar symptoms have also been observed, but the etiology of the disease has often not been investigated. This study aimed to detect and identify the virus species that infect pitaya in Brazil using RT‒PCR and molecular analysis of the coat protein (CP) gene of the viruses. A total of 212 samples of cladodes with suspected symptoms of viral disease were collected from different regions of Brazil and analysed. Four species of potexviruses were detected, cactus virus X (CVX), pitaya virus X (PiVX), zygocactus virus X (ZyVX) and schlumbergera virus X (SchVX), which appeared in single infections (35%) and mixed infections (65%). In the cases of mixed infection, two and/or three species of potexviruses were identified in the same plant. The CVX isolates were divided into two groups due to the deletion of 9 nucleotides at position 41 (5' → 3′) of the CP gene in one of them. This is the first study conducted on the viruses that infect pitaya in Brazil, showing the need to develop control measures that ensure productivity and profitability of pitaya crops in the country. •The occurrence of four potexviruses species: CVX, PiVX, ZyVX and SchVX were detected in Brazilian orchard.•The symptoms were stronger in mixed infections, including rings in the cladodes.•The occurrence of potexviruses indicated that there must be an intensive movement of pitaya seedlings between producers.•The data obtained suggests that the production of healthy seedlings would be fundamental to in pitaya cultivation.