PMV (April 2001)

 Introduction

Pepino Mosaic Virus (PepMV), a highly infectious viral disease of tomato, has recently been confirmed in at least two commercial greenhouses in Alberta. At this time, it is not known how the virus arrived here, but possibilities include infected tomato fruit or seedlings from out-of-province, or inadvertent introduction via contaminated tools, equipment or clothing. The virus can be very easily spread mechanically, so growers should avoid handling PepMV-infected tomato plants and fruit, as well as virus-contaminated equipment, to reduce the risk of infesting their own greenhouses. To date, PepMV has not been a problem on greenhouse crops other than tomato. This disease does not affect the edibility of tomato fruit; however, it may reduce yield and quality, depending on the severity of infection.

Symptoms

The most striking symptoms of Pepino Mosaic on tomato plants occur on the leaves. Stunting of the head of the plant, yellow or dark-colored spots on leaves, brown streaks on stems and flower clusters, and marbling of fruit are characteristic symptoms of this disease. For a detailed description and color pictures of this disease, refer to the Ontario Ministry of Agriculture and Food factsheet "Management of Pepino Mosaic Virus in Greenhouses" which can be found at:
www.gov.on.ca/OMAFRA/english/crops/facts/01-017.htm.

Control Measures

It is important to prevent the introduction of Pepino Mosaic to a greenhouse by using disease-free seed and transplants and non-infested equipment. To minimize the risk of spread and carryover of PepMV in greenhouses where the disease already occurs, strict hygiene at all stages of crop production and thorough clean up procedures between crops are essential. The OMAFRA factsheet mentioned above provides detailed information on ways and means to manage Pepino Mosaic through cultural practices.

PepMV Survey

Alberta Agriculture staff are attempting to pinpoint the number of PepMV-infected greenhouses in the province in order to help curtail disease spread beyond these operations. Specialists will help growers to identify the disease and, if confirmed, will recommend control practices suited to those individual greenhouse operations. If you are a commercial tomato grower and would like to have your crop examined or tested for PepMV, please contact one of the following specialists to make arrangements:

Dr. Ron Howard
Plant Pathologist
Crop Diversification Centre South
Brooks (Ph. 403-362-1328)

Dr. Nick Savidov
Greenhouse Crops Scientist
Crop Diversification Centre South
Brooks (Ph. 403-362-1312)

Dr. Mohyuddin Mirza
Business Development Specialist (Greenhouse Crops)
Crop Diversification Centre North
Edmonton (Ph. 780-415-2303)

Mr. Jim Calpas
Provincial Integrated Pest Management Specialist
Pest Risk Management Unit, AAFRD
Edmonton (Ph. 780-422-4911)