From Our Desk Spud Smart Fall 2010


A Bigger Picture

Every year growers in Canada must deal with late blight, an airborne fungal disease that can cause large losses in the field and in storage. This year, late blight has infested areas not typically known to have outbreaks of the disease. “Usually Western Canada has little problem with late blight, but this year it is widely spread,” says Khalil Al-Mughrabi, a potato pathologist with the New Brunswick Department of Agriculture, Aquaculture and Fisheries.

Recently, Al-Mughrabi completed a fact sheet on late blight as part of a national initiative to reduce the impact of late blight on potato
production in Canada as well as to gain a greater understanding of the disease. This fact sheet has been distributed nationwide to help  potato producing provinces cope with the increased incidence of late blight.

The national initiative, called the National Potato Late Blight Working Group, was established one year ago by the Potato Committee Executive of the Canadian Horticultural Council to serve the national potato industry in Canada after Al-Mughrabi, chairman of the group, identified the need for such an endeavour while trying to identify specific strains of late blight in Canada. “Although we’re a big country, I wasn’t able to find anyone to do strain identification for us,” says Al-Mughrabi.

The group is made up of one representative from each potatoproducing province and is focused on creating a national late blight identification program, research program, extension program and national potato website. Eventually, Al-Mughrabi would like to see information like this developed for all diseases of potatoes.

Canadian growers will be directly affected by the findings of this working group because once the strains are determined, appropriate actions and/or chemicals to control infestation can be implemented. New strains of late blight are evolving, also developing new characteristics such as the ability to overcome resistant cultivars as well as more aggressive strains and the ability to adapt to environments previously unfavourable to the pathogen. For example, some strains are already resistant to metalaxyl.

At the moment, Al-Mughrabi is a busy man: in September he sent samples of pure cultures of the pathogen from across the country for genotyping to research scientists at Agriculture and Agri-Food Canada in Alberta and Prince Edward Island. He’s also developed a webinar that growers can access from anywhere in the country on how to manage late blight, and he’s working on more fact sheets to post to the CHC website as well as presentations, videos and a “Potatoes in Canada” icon for the CHC home page. The creation of the group has generated much excitement in the world of horticulture in Canada, “Once we created this group, most of the potato pathologists from across the country expressed interest in becoming part of it,” he says. At the end of the year he hopes the group will have gathered enough information on late blight to form a bigger picture of what is happening in all potato-producing regions across Canada.

Continuing support of these national efforts is what will strengthen our potato industry now and in the future.

By Kari Belanger