An update on cactus viruses (2025)

The Cactaceae family is known for its adaptation to dry habitats and peculiar morphology of different forms and sizes, composed of perennial succulent stem-bearing spine plants, lacking broad green leaves. Cactaceous plants have been cultivated for food production, medicinal and cosmetic products, animal fodder, construction, and ornamental applications. Among them, the widely cultivated dragon fruit (genus Hylocereus and Selenicereus) is gaining prominence. Physiologically, they have reduced their photorespiration and achieved higher water-use efficiency rates than the other metabolic types. For this reason, cacti have the potential to become a stable food source in the future scenario of global climate change. Many pests and diseases have been described affecting cactaceous plants, including viruses. Viral infection of cacti is mostly asymptomatic though examples of mottling, chlorotic, or necrotic ringspots have been described, and their economic impact is unknown as yet. The cytopathic effect, such as spindle-shaped inclusions in epidermal and parenchymal cells, was first observed in the late 19^th century. Subsequently, it was discovered that they were indeed aggregate particles of potexvirus. Until the turn of the 21^st century, few viruses among cacti were known (genera Potexvirus, Tobamovirus, Carlavirus, and Alphacarmovirus); however, since the advent of advances in molecular tools, several new cactus viruses (families Tospoviridae, Solemoviridae, Caulimoviridae, Geminiviridae and Genomoviridae) have been described. Currently, 31 distinct virus species, belonging to 13 genera of nine families, as well as three viroids of two genera, have been documented to naturally infect cacti. This review updates the number of known cactus viruses, providing a brief description of each of them.

Keywords:
Hylocereus; Selenicereus; Opuntia; Cactaceae; virome