Yellow leaf curl virus of Solanaceae

The causative agent of this disease is the Begomovirus solanumflavusyunnanense, a member of the Geminiviridae family. This pathogen is a systemic plant virus that infects the plant's vascular tissues, severely disrupting physiological functions such as photosynthesis and nutrient transport. As a viral disease, it is impossible to cure once the pathogen has established itself within the host plant's cells.

The primary hosts for this virus are plants within the Solanaceae family, including tomatoes, peppers, and eggplants. The virus is highly host-specific but can also be found in various weeds that belong to the Solanaceae family, which serve as reservoirs for the virus during the off-season, enabling it to persist in the field environment.

Symptoms typically manifest as yellowing or chlorosis of the leaf margins, accompanied by upward curling or cupping of the leaves. Infected plants often show stunted growth with significantly shortened internodes. As the disease advances, the plants produce fewer flowers, and fruit development is either completely inhibited or results in severely deformed, non-marketable produce.

The transmission of the virus is almost exclusively facilitated by the tobacco whitefly (Bemisia tabaci). This insect acts as a vector, acquiring the virus by feeding on infected plant tissues and subsequently transmitting it to healthy plants. Outbreaks are most common in hot and dry climates, which favor the rapid proliferation of the whitefly population and facilitate the spread of the virus across fields.

The economic impact of this virus is severe, leading to significant yield losses if infestations are not controlled early in the growing season. Since there is no chemical cure for viral infections, management focuses on preventing the virus from entering the crop. Key control strategies include:

• implementing stringent integrated pest management (IPM) to control whiteflies;
• growing resistant or tolerant plant varieties;
• using fine-mesh screens in greenhouses to prevent vector entry;
• eradicating weeds that host both the virus and the whitefly;
• strictly removing and destroying symptomatic plants to eliminate the source of the virus.