Tomato leaf curl Sri Lanka virus

Tomato leaf curl Sri Lanka virus (Begomovirus solanumsrilankaense) is a destructive plant pathogen belonging to the Geminiviridae family. It primarily attacks Solanaceae crops, posing a serious threat to greenhouse and open-field tomato production by inducing severe systemic infection throughout the plant tissues.

The transmission of this virus is exclusively dependent on the silverleaf whitefly, Bemisia tabaci. The virus is acquired by the insect during feeding and is transmitted in a persistent-circulative manner. This means that once a whitefly has acquired the virus, it remains a vector for the duration of its life, effectively spreading the pathogen among host plants in the vicinity.

Symptoms of the infection typically include severe leaf curling, marginal chlorosis, and the upward rolling of leaflets. Plants infected at an early stage exhibit extreme stunting and stunted growth patterns. The reproductive output is heavily compromised, as flower abscission occurs frequently, and the few fruits that develop are often small, discolored, or malformed.

Environmental conditions that favor high whitefly populations, such as warm temperatures and high humidity, significantly accelerate the spread of Begomovirus solanumsrilankaense. In regions where these conditions are constant, the virus can survive in a wide range of weed hosts, creating a perpetual cycle of infection that challenges seasonal planting cycles.

Management and prevention strategies focus on reducing vector pressure and improving cultural practices:

• Implementing strict greenhouse exclusion practices using high-quality insect-proof netting.
• Applying effective insecticide programs to keep whitefly populations below the economic injury level.
• Utilizing resistant or tolerant tomato cultivars bred for begomovirus resistance.
• Removing and destroying infected plants promptly to reduce primary inoculum sources.
• Managing weed populations surrounding the cultivation area to eliminate viral reservoirs.