Sweet potato leaf curl virus

The disease is caused by Begomovirus ipomoeasichuansecundi, a plant virus from the Geminiviridae family. As a systemic pathogen, it significantly alters the plant's physiological processes, leading to stunted growth and reduced yields. The virus relies on a vector to spread throughout agricultural fields efficiently.

The primary host for this specific virus is the sweet potato (Ipomoea batatas). It can also infect other related species in the Convolvulaceae family, which serves as a host range that allows the virus to persist in the environment even when main crops are not present.

Symptoms are characterized by pronounced leaf curling, upward or downward leaf rolling, vein yellowing, and interveinal chlorosis. Infected plants typically display severe stunting, reduced leaf size, and occasionally, a bushy appearance due to shortened internodes, which directly impacts the quality and size of storage roots.

Transmission occurs through the whitefly Bemisia tabaci. The insect acquires the virus while feeding on infected plant sap and transmits it to healthy plants during subsequent feeding sessions. The virus-vector relationship is persistent, meaning a single whitefly can remain infectious for a significant period, facilitating rapid spread within the field.

Management strategies focus primarily on vector control and the use of resistant germplasm. Integrated Pest Management (IPM) is crucial, involving the application of insecticides to reduce whitefly populations and the physical removal of symptomatic plants to reduce the inoculum pressure. Additionally, cleaning the field borders and using clean, virus-indexed propagation material are fundamental to preventing initial outbreaks.