Sweet potato chlorotic fleck virus

Sweet potato chlorotic fleck virus (SPCFV) is a significant plant pathogen belonging to the genus Potyvirus that specifically affects sweet potato (Ipomoea batatas) crops. It is known to cause systemic infections, which often manifest as chronic diseases when combined with other viral agents. The presence of this virus can lead to substantial economic losses in agricultural production worldwide.

Symptoms of an SPCFV infection typically include chlorotic flecking or spotting on the leaves, slight leaf deformation, and reduced overall plant vigor. In severe cases, the infected plants exhibit stunted growth, which leads to a decrease in the size and quality of the storage roots. The visible symptoms may vary depending on the viral strain and the specific cultivar of the host plant.

The biology of the virus is characterized by its transmission through aphid vectors in a non-persistent manner. This means that aphids can acquire and transmit the virus within seconds of feeding. Furthermore, the vegetative propagation of sweet potatoes through cuttings or tubers is the primary method of long-distance dissemination, as the virus can remain latent in planting material for long periods.

Environmental conditions that favor the proliferation of aphid populations significantly increase the spread of SPCFV within fields. The virus thrives in warm regions where both the host plants and the vectors are active throughout the growing season. Alternative hosts within the Convolvulaceae family can serve as a reservoir, allowing the virus to persist in an area even when sweet potato crops are not present.

Effective management and control strategies focus on preventing the introduction and spread of the virus. Key practices include:

• Utilizing virus-indexed, tissue-cultured plantlets for new plantings.
• Implementing rigorous sanitation procedures to eliminate infected plants immediately.
• Applying insecticides to manage aphid populations during critical stages of plant development.
• Maintaining a clean environment by controlling weeds that act as alternate hosts for the virus.