Tomato leaf curl Taiwan virus

Pathogen and disease type. Begomovirus solanumtaiwanense is a member of the Begomovirus genus within the Geminiviridae family. It is a devastating plant virus characterized by a circular single-stranded DNA genome. The pathogen causes systemic infection, leading to physiological disruption and severe stunted growth in susceptible host plants.

Host range. The virus primarily affects crops within the Solanaceae family. Tomato (Solanum lycopersicum), pepper (Capsicum annuum), and potato are the most significant economic hosts. Additionally, various wild solanaceous weeds serve as natural reservoirs for the virus, allowing it to persist in the field environment throughout the year.

Symptoms and signs. Typical symptoms include severe curling and upward rolling of leaves, along with chlorosis and reduced leaf size. Infected plants often show stunted internodes, resulting in a bushy or shrubby appearance. Fruits on infected plants are often small, malformed, or fail to develop entirely, significantly impacting crop yield and quality.

Conditions for development. The spread of this virus is strictly dependent on the whitefly Bemisia tabaci, which acts as the primary vector. High temperatures and humidity accelerate the reproduction of the whitefly, thereby increasing the incidence of viral transmission. The virus is acquired by the insect during feeding and is transmitted in a persistent, circulative manner.

Damage and preventive measures. The economic impact is substantial due to yield loss and marketability reduction. Effective prevention strategies include:

• Utilizing resistant or tolerant cultivars.
• Rigorous weed management to eliminate alternative hosts.
• Controlling whitefly populations with appropriate insecticides or biological agents.
• Employing physical barriers like insect-proof netting in greenhouses.