Disease guide

Pepper Golden Mosaic Complex: Pepper huasteco yellow vein virus (PHYVV) [synonym: Pepper huasteco virus (PHV)]. Sinaloa tomato leaf curl virus (STLCV) and additional uncharacterized begomoviruses

Sweet potato whitefly (Bemisia tabaci), Silverleaf whitefly (B. argentifolii)

Symptoms vary depending on the variety infected, the viruses present, environmental conditions and age of plant at the time of infection. Early symptoms may include yellow vein-etching and clearing, and distortion of young leaves. As infection progresses, symptoms of chlorosis, mosaic and mottling develop, and distortion is more prominent. Infected plants are stunted, and fruit are small, discolored and distorted. This family of viruses can cause significant yield reductions in peppers and eggplant.

The pepper golden mosaic complex is comprised of closely related viruses that infect in many combinations. Pepper huasteco yellow vein and Sinaloa tomato leaf curl are serious diseases of pepper grown in Mexico, where large areas of hot peppers are grown and whiteflies are established. Geminiviruses are spread from host to host by whiteflies in a persistent manner and are not mechanically transmitted. These viruses also infect tomatoes, which are a preferred whitefly host. Consequently, tomatoes can be a source of vector and virus to nearby pepper fields.

Overlapping cropping systems make control of these viruses and their vectors very difficult. Exclude whiteflies from nurseries using protective netting or screenhouses to grow virus-free transplants. Apply systemic insecticides early to reduce whitefly populations and limit the spread of these viruses. In mature plants, it is difficult to achieve complete insecticide coverage of leaves to effectively eradicate all whiteflies. Even low whitefly populations efficiently transmit geminiviruses. Destroy residual crops after harvest and maintain a host-free period to help manage whiteflies and geminiviruses.