Several diagnostic labs in the Northeast U.S., as well as our own lab here at the University of Guelph, have received diseased calibrachoa suspected to have chili pepper mild mottle virus (CPMMoV). The supplier has alerted growers of this issue.
Although CPMMoV is NOT a regulated disease by CFIA or the USDA, it can still affect the quality of your crop and lead to losses.
Read on for a link to an excellent blog post on the topic written by Michigan State University Extension. This includes symptoms to look out for, the importance of testing, and what to do if you have it.
What is CPMMoV?
CPMMov is a virus that belongs to Tobamovirus group. Las week Electronic Grower Resources Online (e-GRO) put out an alert that describes the symptoms, along with detailed pictures (read it here: Alert 11.20).
I Suspect I have CPMMoV Plants – What Now?
Check out the following blog post by MSU Extension. As you can tell from the title, scouting for symptoms, rouging out infested plants and disinfection is your best way to control a virus like this. Luckily, CPMMoV is NOT vectored by insect pests, so focus on reducing spread via mechanical means.
Testing to Confirm CPMMoV:
As mentioned in the MSU blog post, CPMMoV will cross react with test strips used for Tobacco Mosaic Virus, so you can use AgDia’s TMV strips on farm. However, asymptomatic plants (i.e. plants not showing visible symptoms) are unlikely to test positive using this method, giving you a false sense of security. Repeated scouting and retesting is necessary to stay on top of the issue.
Alternatively, you can send plants to the Lab Services at the University of Guelph or another accredited lab and they can detect Tobamoviruses using RT-PCR. To confirm it is actually CPMMoV, you would need to ask for follow up DNA sequencing. However, if you have a positive Tobamovirus test, matching symptoms, and if you received a noticed from your supplier about risk, you can be pretty sure it’s CPMMoV.
Disinfection:
If you find the presence of CPMMoV or another tobamovirus on your farm, tools, trays and other surfaces should be sterilized to prevent spread to non-infected plants and other crops that may be susceptible. Studies show that Virkon (2%), and bleach (10%) are highly effective at destroying TMV, while other suggested strategies (e.g. the use of milk to coat and deactivate the virus) were not.