Invasive insects could threaten Quebec crops, experts warn

CTV National News: Havoc of the lanternfly John Vennavally-Rao reports on the havoc the invasive lanternfly is having and could have on the wine and fruit industry in U.S. and Canada.

New insects are appearing regularly in Canada, and some of them may pose a threat to Quebec's crops.

"In the last few years, with international trade and probably climate change, there are definitely more and more risks associated with (these) species," said biologist-entomologist Jean-Philippe Légaré, who works at a plant-protection lab with Quebec's Ministry of Agriculture, Fisheries and Food (MAPAQ). "Add to that the fact that we have cultivars that we can grow further north, the pests follow those crops as well.'

Last month, the Canadian Food Inspection Agency (CFIA) issued a warning regarding the spotted lanternfly, an insect that originated in Asia, but has been well-established in the United States since 2014.

The spotted lanternfly is a brightly coloured insect that looks like a butterfly, but is not. Instead, it belongs to the same family as aphids. Its arrival in North American is likely a consequence of international trade.

Its presence in New York State, only 45 kilometres from the Ontario border and the Niagara wine region, suggests it may arrive in Canada soon.

"Its spread over long distances is facilitated by human transport of infested material or objects containing masses of eggs," reads the IRIIS phytoprotection website reads, managed in part by MAPAQ.

By feeding on the sap of plants, the spotted lanternfly can cause significant losses in vineyards as well as in fruit and forestry crops.

For the moment, both the CFIA and MAPAQ are focusing on awareness -- posters have been put up at rest stops, for example, so that people returning from the United States check their vehicles for the insect.

"Normally, traps will be placed in areas where the risk of introduction is highest. In this case, we would have put them in vineyards near transportation routes. Except that for (the spotted lanternfly), there is no method of capture," said Légaré.

CLIMATE CHANGE

Although Légaré believes that it is difficult to measure the impact of climate change on the presence of new pests, certain changes in climate do play a role.

"We see it in some pests, as soon as there is a milder winter, the populations in the spring are higher," he said.

Longer summers are also appreciated by insects, which are cold-blooded animals whose metabolism is influenced by temperature.

"For example, if an insect in the past made one generation per year, today there are some insects that are able to make two generations, that will make two egg stages during the year," he said.

The effects of climate change are also already being observed in agriculture, and particularly in grape cultivation, also called viticulture.

Geographer Frédéric Lasserre, who has studied the development of Canadian vineyards and the impact of climate change, has already observed warming across Quebec.

"There is clearly an increase in the number of cumulative degree-days in a year. This means that during the growing season -- from spring to harvest -- the heat has increased, which allows for a faster and more efficient ripening of most grapevines," said the professor at Laval University's geography department. "These temperature changes come with their own set of adaptations. On the one hand, new grape varieties can be planted in Quebec and further north in the province, but on the other hand, this comes with certain risks. For example, milder winters could jeopardize the production of ice wines."

"With warming, a certain number of parasites and diseases are coming to Quebec that didn't exist before, which we were protected from thanks to the cold temperatures in winter," said Lasserre.

In crops other than grapes, the arrival a few years ago in Quebec of an insect could probably be linked to climate change, milder winters and a longer growing season, Légaré said.

"In 2018, the squash borer, which has always been a troublesome pest in most cucurbit (also known as gourd) crops in the United States, was detected in Montérégie," he said. "Since then, populations have spread throughout the cucurbit-growing regions of Quebec."

The larva of this moth burrows into the stems of squash and melon plants to feed, causing them to wilt.

ADAPTATION NEEDED FOR 'COMPLETELY NEW' INSECTS

In order to better understand the insects that affect Quebec crops, projects have been set up to study them. This is the case for strawberry pests, which have a significant economic impact, as Quebec is the leading producer in Canada.

Since last year, the team of plant pathology professor Edel Pérez Lopez of Laval University has been studying grasshoppers in strawberry cultivation and their role as vectors of viral and bacterial diseases.

"We have found many more insects, and there are also many insects that are completely new to the province, if not all of eastern Canada. (They) can transmit different bacterial and viral diseases," said Pérez Lopez.

In particular, he has been looking for the species of grasshopper that transmits the green petal disease that affects strawberries, since 20 cases have been recorded this year, compared to 23 in 10 years.

Of the 40 species identified, eleven are "completely new" to the province, according to Pérez Lopez.

By studying the grasshoppers, the professor and his team from the Edelab laboratory hope to better understand how they work and to propose means of control to the agricultural producers, with whom they work.

The objective is to reduce the use of insecticides -- by spreading them more efficiently -- and to develop biological control methods.

The first conclusions are expected by the end of the year.

Other new insects that could affect Quebec crops:

-- This report by The Canadian Press was first published in French on Oct. 8, 2022