Farmers taking steps to control late blight

Eric McCarthy
Published on September 2, 2014
potato field

ALBERTON -- When he discusses the harmful effects of late blight and the steps that need to be taken to prevent its from spreading, Gary Linkletter speaks from experience. His is one of the farms where late blight recently made its presence felt. 

“We walk every field every week,” said Linkletter, who is chairman of the P.EI. Potato Board. “They never saw it the week before and this week there was so much there that we had to kill some of it.” He was referring to killing down part of a potato field to prevent the blight spores from spreading.

The potatoes can be harvested once the tops are completely killed, but the yield will be significantly reduced because of the shorter growing period.

Most of the late blight found so far – there have been at least 10 confirmed cases, mostly in the Summerside, Spring Valley, Freetown, Breadalbane and Wilmot Valley areas – are of an aggressive US23 strain, Linkletter said in relaying what he has learned.

 “If you didn’t have any protectants on, it would just take the field out inside of a week,” Linkletter described the seriousness of late blight. “With protectants on, it does slow it down some.”

Late blight, he pointed out, is what caused the 1845-1851 Irish Potato Famine.

Pointing out spores can be blown into a field from many kilometers away, Linkletter stressed farmers need to spray regularly in hopes of preventing the spread of late blight which he described as a community disease. “A person tries to have a good, solid protectant program on,” he said, but stressed it is impossible to protect all surfaces of the plant.

Linkletter said it is believed the US23 strain first made it to P.E.I. on tomato plants. Tomatoes and potatoes are closely related.

“An infected potato field will take out a home garden – the tomato plants in a home garden – but a tomato plant in a home garden will also infect a potato field,” he noted.

“You don’t what to be the one who has it, because you’re going to spend a lot of money dealing with it and lose some of your crop,” he acknowledged.