Curtovirus

Curtovirus is a genus of plant viruses belonging to the Geminiviridae family, known for causing severe diseases in a wide range of economically significant crops. These viruses are characterized by a circular single-stranded DNA genome and are responsible for substantial yield losses globally, particularly in arid and semi-arid agricultural regions.

The host range of Curtovirus is extensive, primarily affecting dicotyledonous plants. Key agricultural crops susceptible to these viruses include sugar beets, tomatoes, beans, peppers, and various cucurbits. These viruses are phloem-limited, meaning they colonize the plant's vascular tissue, disrupting nutrient transport and physiological development.

The transmission of the virus is strictly mediated by insect vectors, specifically leafhoppers such as Circulifer tenellus. The virus is acquired by the insect through feeding on infected plant tissues and is transmitted in a persistent, circulative manner. Once an insect acquires the virus, it remains infective for the remainder of its lifespan.

Symptoms of Curtovirus infection often manifest as severe leaf curling, stunting, chlorosis (yellowing), and internal necrosis. In many crops, the terminal leaves show characteristic upward rolling and thickening, and the entire plant typically displays a dwarf-like architecture, drastically reducing its capacity for fruit or root production.

Effective management requires an integrated approach because direct chemical control of the virus itself is not possible. Strategies focus on limiting vector populations and minimizing exposure:

• Utilizing resistant or tolerant crop cultivars developed through breeding.
• Implementing precise insecticidal programs to control leafhopper populations at the field borders.
• Eliminating host weeds in and around fields to remove the virus reservoir.
• Adjusting planting schedules to avoid peak migration periods of the vector populations.
• Applying reflective mulches to deter insect landing on sensitive young plants.