Pepper Mild Mottle Virus - Prevention, Control and Management

Prevention, Control and Management

Up until 2005, the primary means of prevention was a pre-plant treatment of Bromomethane or methyl bromide. The import and production of this fumigation chemical was banned under the Montreal Protocol. A modern organic method of prevention was found by a Japanese study on soil adsorptions role in the adsorption of PMMoV. The study found that increased humus content in a soil will have an inhibitory effect on PMMoV adsorption.

As with all plant viruses, but especially with those in the Tobamovirus genus, avoidance is the best means of control. Growers must practice good sanitation procedures and only plant clean seeds. Growers must also use caution when handling plants, plants with abrasions or wounds give the virus an opportunity to enter the tissue of the plant.There are no chemical or biological control methods that can be used to control the disease once the plant is infected. Though often a challenge, accurate identification of PMMoV is key to successful control of the disease. (See reference 7 for a detailed description of control measures for this virus.)

Diseased plant material will remain infectious until completely broken down. Tillage, increased irrigation, and high temperatures encourage the breakdown of plant material in the soil. Any infected plant material in the soil can serve as a source of inoculum for subsequent crops so crop rotation should be practiced, if possible. Volunteer peppers and weeds, particularly those in the Solanaceae family (such as nightshades), should be removed to reduce possible sources of infections. Due to the fact that smoke can spread the disease, burial or composting of the diseased plants should be implemented rather than burning. The composted diseased plant remains should not be used on a pepper crop or other Solanaceous crops.