Pepper Mottle

Pepper mottle affects more than peppers. This viral disease infects eggplants, groundcherries, potatoes, tomatillos, and tomatoes. Especially tomatoes.

Tomatoes infected with pepper mottle (Scot Nelson) Public Domain

First identified in an Arizona Tabasco pepper in 1969, pepper mottle is a type of Potyvirus, similar to potato virus (PVY). It has since been found in several states and countries. Also known as chili mottle virus and pepper mottle potyvirus, this is not the same disease as pepper mild mottle, which we will discuss tomorrow.


Pepper mottle symptoms

Pepper model symptoms vary by the species infected and the age of the plant at the time of infection. Initially, peppers will show vein clearing, which later shifts to dark vein banding, mottling, crinkled leaves, and deformed fruit. [Unfortunately, I was unable to find a photo that I could use.]


Tomatoes have similar leaf and stem symptoms, but the fruit ripens unevenly with green, orange, and yellow areas that never fully ripen. Infected plants are stunted and produce significantly less fruit. Diagnosis can be difficult because pepper mottle often occurs at the same time as other infections and can look a lot like cucumber mosaic.


Pepper mottle management

The pepper mottle virus is spread by aphids. Those aphids are likely to hide out in weeds from the nightshade family. This disease can also be spread mechanically by working with an infected plant and then moving to a healthy plant.


To reduce the chance of pepper mottle in your garden, remove Datura and other nightshade weeds and any rouge tomatoes. [I know, it’s hard to get rid of volunteer tomato plants. But they very often harbor diseases so add them to the compost pile and focus on the ones you planted on purpose.]


Garden tools can carry the virus, so it’s a good idea to sanitize them between plants any time disease is suspected. Bathroom cleaners work well. Control aphid populations with horticultural oils and insecticidal soaps.


When shopping for seeds and seedlings, investing in certified pest- and disease-free plants can save you a lot of time and effort later in the growing season and future years. Some pests and diseases can stick around for a very long time. Resistant varieties are being developed. When shopping for plants, look for the PepMoV or PeMV on plant labels.