The pea leaf weevil—once the bane of the Canadian pulse grower—is now the focus of research aimed at its destruction using promising new tactics that pit bug against bug.
The project, led by Dr. Meghan Vankosky of Agriculture and Agri-Food Canada in Saskatoon, investigated the use of natural predators and other methods to control pea leaf weevil (PLW) in field pea and faba bean.
At least, that is the end goal. For now, PLW is still a very real problem, especially for field pea and faba bean growers in the Prairies—and the research, while promising, is still in the exploratory phase.
This is not to say it has not yielded results farmers can apply to their crops right away, Vankosky said.
PLWs can be serious pests, especially when they invade a crop in high numbers. Larvae feeding within the root nodules can do enormous damage, reducing the plant’s capacity for nitrogen fixation and leading to poor growth, reduced seed yield, and higher susceptibility to disease and infection. Adult
weevils consume the leaves in spring and before they overwinter.
“Insecticides applied to the leaf are not that effective, while systemic insecticides, which are absorbed into the plant itself, are more effective but costly,” Vankosky said.
Her project, Integrated pest management of pea leaf weevil using biological control and low insecticide-input alternatives, began in 2016 when she and a colleague observed a PLW infestation on volunteer peas along the edge of a harvested pea crop. “That led me to ask if pea or bean seedlings could be used as trap crops to attract adult weevils,” she noted.
Trap crops are often used to lure agricultural pests from main crops growing in neighbouring rows.
Vankosky’s field research in Lacombe, AB demonstrated that field pea and faba bean are, indeed, effective traps for PLW, drawing the pests to rows where they can be destroyed via the focused application of insecticides. Future studies will explore the effectiveness of this approach and various insecticides as weevil-destroying agents.
Another aim of the project was to look for natural PLW enemies to reduce or eliminate the need for insecticides. Enter Pterosticus melanarius, aka the Rain-Beetle. This common ground beetle is highly active in field pea and faba bean crops, according to the study. And it is hungry for pea leaf weevil.
“Best of all, this species is a generalist predator, so it could contribute to the suppression of other pest populations,” Vankosky said.
Practicing reduced tillage and avoiding broad-spectrum insecticide applications protects these beetles and improves the chances of managing PLWs and other pests.
Vankosky said additional research will assess P. melanarius’s efficacy as part of an integrated pest management program, especially when combined with trap crops.
For more information about ground beetles and other natural enemies of pulse pests, visit prairiepest.ca and fieldheroes.ca.
The Pulse Research Cluster includes Alberta Pulse Growers, Manitoba Pulse and Soybean Growers, Ontario Bean Growers, Saskatchewan Pulse Growers and Pulse Canada and is supported by the Agriculture and Agri-Food Canada AgriScience Clusters Program under the Canadian Agricultural Partnership.

Imagine spending 50% less on fuel and chemical inputs for a specific crop without any sacrifice to yield. This tangible advancement in agriculture was the result of years of research and scientific dedication happening behind the scenes in a project led by Dr. Parthiba Balasubramanian at the Agriculture and Agri-Food Canada (AAFC) Lethbridge Research and Development Centre.
Balasubramanian’s research was focused on developing dry bean varieties with high yield, early maturity, strong lodging tolerance, and high seed quality, all for production under irrigation in Alberta. This process included the evaluation and integration of disease resistance to common bacterial blight (CBB), white mould, and anthracnose.
White mould is the number one production concern for dry bean farmers in Alberta, according to Balasubramanian. Over the last number of years, his team sought to transfer white mould resistance traits from bean varieties not typically grown in Alberta into early maturing bean varieties that farmers currently have in their rotations.
Five years ago, when this project started, he knew that it would be a lot of work. Incorporating disease resistance into a bean variety is not easy, according to Balasubramanian, but the hard work paid off.
“We were successful in developing pinto, great northern, black, red, and navy bean lines with both avoidance to white mould in upright plant growth and lodging situation and partial physiological resistance to white mould,” Balasubramanian said, adding that these lines are not yet commercially available, but will be within the next 10 years. “Improved resistance to common bacterial blight were also developed in some varieties of pinto beans.”
Disease-resistant varieties can reduce input costs associated with fossil fuel and chemical usage up to 50% or more, and contribute to environmentally sustainable production practices, he added.
As a result of years of research funded by farmers and government, both input cost reduction and tangible research results will become a reality.
“Currently, dry bean cultivars with avoidance to white mould are in commercial production in Alberta,” said Balasubramanian, who recognizes this as a ground-breaking advancement for farmers that’s also exciting for researchers.
He is using the lines that his team developed to have avoidance and partial physiological resistance to white mould as parents in a breeding program that will see them commercially available to farmers within the next 10 years.
An additional objective of the project was to transfer partial resistance to CBB into early maturing dry bean lines. Currently, most dry beans do not have genetic resistance to CBB, which is a seed-borne disease that can infect plants wounded by weather events like hailstorms or strong winds.
These varieties are in development, and once they are available Alberta farmers will have access to dry beans that will allow them to cut their input costs, meet or exceed sustainability targets, and maximize profitability.
The Pulse Research Cluster includes Alberta Pulse Growers, Manitoba Pulse and Soybean Growers, Ontario Bean Growers, Saskatchewan Pulse Growers and Pulse Canada and is supported by the Agriculture and Agri-Food Canada AgriScience Clusters Program under the Canadian Agricultural Partnership.

Fresh insights from studies into three nematode species aid in strengthening market security for Prairie growers who export their pulse crops to countries with strict quarantine rules.
Dr. Mario Tenuta, a soil ecologist at the University of Manitoba and the project’s principal investigator,
hopes the studies will also raise awareness about the issues nematodes can present to pulse farmers and provide recommendations for how they can deal with them.
Often referred to as roundworms, nematodes are microscopic invertebrates with smooth, unsegmented bodies and, usually, a worm-like body shape one
to two millimetres long. Many feed on plants, using needle-like spears to suck the contents of plant cells. Others carry viruses that can damage crops. Most, however, are harmless to plants, and enrich the
soil by feeding on decaying matter and other living organisms.
“We know so much more about fungal and bacterial crop diseases as a result of better understanding nematodes,” Tenuta said. “Nematodes are everywhere, but they have been relatively neglected as a focus of study on the Canadian Prairies.”
One of the project’s studies examines Ditylenchus, the stem nematode of Canada thistle. Previous research showed that Ditylenchus does not like the pulse crops that we grow on the Prairies, or other crops like canola and wheat.
“Now we are looking at vegetable crops that grow in countries we export our pulses to,” Tenuta noted.
Inside a greenhouse at the University of Manitoba, Tenuta and his team introduced the Canada thistle nematode to okra, chillies, potatoes, gourds, and other plants popular in countries like India to see if the parasite would attack them—or could survive on them at all.
The researchers may repeat the study in the coming months at high temperature to mimic summer of the countries Canada exports its pulses to just in case that has any impact on nematode reproduction levels.
Tenuta’s research team was also asked to investigate the root lesion nematode, Pratylenchus, which is present in nearly a quarter of all fields on the Prairies.
“Why does it thrive here? What plants does it eat? We are looking for baseline knowledge we can build on with later research,” Tenuta said.
It turns out the root lesion nematode loves soybean and, to a lesser extent, chickpea. Tenuta worked with Dr. Syama Chatterton, a plant pathologist with Agriculture and Agri-Food Canada Lethbridge, who planted varieties of soybean in tubes filled with soil that had anywhere from zero to many of the nematodes living in it. Then they compared the parasite’s reproduction rates.
“We have confirmed this nematode does like some varieties of soybean more than others, but it does not seem to harm the soybean,” Tenuta explained. “We are still analyzing the data to get the full picture.”
Tenuta and his team are also investigating a mysterious chickpea disease wreaking havoc on crops in southern Saskatchewan. The disease may have something to do with the pin nematode, Paratylenchus.
“We are finding incredibly high densities of the pin nematode in soil samples loosely related to occurrences of this syndrome,” Tenuta said, “but several criteria must be met before we can confirm the nematode is actually responsible for the disease.” He and his team continue to work on this emerging pest.
By understanding the relationship between nematodes and pulses grown on the Prairies today, researchers like Tenuta can help growers and plant scientists prepare for a changing climate tomorrow.
“One of our strengths on the Prairies is our diverse crop rotation, which keeps some populations of these nematodes down,” he said. “However, as our climate changes, and we introduce new crops or crops with longer growing seasons, we could have new nematode species appear and thrive under warmer conditions.”
These include some of the more threatening nematode species that have yet to make an appearance on the Prairies. For example, Tenuta’s team recently discovered the soybean cyst nematode (SCN) in five Manitoba rural municipalities. SCN is one of the most significant diseases of soybean. Tenuta hopes that raising awareness about its presence and reaching out to farmers will ensure it is not as damaging here as it is elsewhere.
“Thanks to this work, we have the infrastructure, talent, technicians, and students who are being trained to jump in there and handle any potential issues that may arise,” Tenuta said.
His research is helping Canada’s pulse farmers understand the impact these microorganisms have on market security and crop health today, and in the face of an uncertain future.
For more information, visit soilecology.ca/pulse- nematodes/
The Pulse Research Cluster includes Alberta Pulse Growers, Manitoba Pulse and Soybean Growers, Ontario Bean Growers, Saskatchewan Pulse Growers and Pulse Canada and is supported by the Agriculture and Agri-Food Canada AgriScience Clusters Program under the Canadian Agricultural Partnership.

It is sometimes tempting to consider financial outcomes in annual rather than multi-year increments. Farming is a great example because a single year’s activities are well-defined with inputs and efforts for that year resulting in an entire year’s worth of profits. To keep annual cash flows healthy, producers must juggle a lot of factors and a major consideration is the projected sales price of any given crop.
However, if producers were presented with scientific, multi-year and multi-growing-region models that prove explicit, long-term gains when using a diversified system to maintain productivity and profitability—would that help simplify and ease some of the stress of producers’ annual planning?
Adjunct Professor Dr. Elwin Smith and Professor Dr. Danny LeRoy (Department of Economics, University of Lethbridge) are the principal investigators for the research project entitled Economic value of diversified cropping systems. The four-year project ran from 2018-19 through 2021-22 and eight collaborators from the Universities of Lethbridge, Alberta, Manitoba; AAFC Lethbridge and Lacombe; and Alberta Agriculture and Irrigation worked with Smith to produce research results that compared productivity and profitability of two cropping systems. Those systems are: 1) Short crop rotations, where annual crop prices and resulting profit are often the major consideration but can risk future growing conditions on the farm and long-term profits; and 2) Diversified crop systems, which take into consideration multi-year productivity, farm environment health (reduced plant disease, weed pressure from herbicide resistance and insect damage), and lower overall input costs. In recent years, typically high-production acres of crops in Canada are canola, pulse, soybean and corn.
“These crop choices reflect the current higher net returns from these crops, at least in the short term,” Smith stated. “Until recently, few long-term costs associated with short crop rotations and frequent planting of one or two crops were observed by producers. However, there is accumulating evidence that plant diseases, such as blackleg (Leptospaeria maculans) and club root (Plasmodiophora brassicae) in canola, the root disease Aphanomyces euteiches in pea and lentil, and leaf diseases on cereals such as barley, increase with short rotations. The long-term productivity and profitability of these crops and rotations is reduced with increased disease levels.”
Weeds, diseases and insect pests (all referred to as ‘pests’ in this study) quickly adapt through intensive selection pressure or environmental conditions ideal for the ‘pest’ when constantly using the same control chemicals, cultural practices and cropping system. Production costs will continue to increase if a more integrated method of controlling pests (including more diverse crop rotations) is not adopted by producers. To be competitive and profitable, producers need to know: 1) the profitability of different cropping systems, including diversified crop rotations and pest control practices; and 2) the benefit of diversified cropping systems in preventing a decline in long-term productivity and profitability, and 3) the business risk associated with different cropping systems.
With the goal in mind, a variety of specific rotations were identified and analyzed to delineate and quantify the trade-offs between short pulse crop rotation lengths (few break years between pulse crops) and longer rotation lengths with a greater diversity of crops. The variability of return (risk) was evaluated because crop yields and prices, and the damage from the disease varies from year-to-year.
While looking at several crops (including canola, wheat and corn), lentil and field pea based crop rotations were included particularly to evaluate the economics in the presence of the root disease Aphanomyces. Prior to the disease becoming prevalent throughout the Prairies, crop rotations with frequent pulse cropping were more profitable. In many cases, pulses were grown every second year in the same field.
This strategy now appears less lucrative. Yield damage to pulses from Aphanomyces reduces the profitability of short pulse-based rotations.
A risk-returns assessment focused on three regions in the semi-arid Prairies where pulse-based rotations are used extensively: the Brown Soil Zones of Saskatchewan and Alberta, and the Dark Brown Soil Zone of Saskatchewan. The analysis evaluated the net cash flow for a situation of no yield damage from Aphanomyces, determined the level of the disease at which the net cash flow was higher for recommended seven-year rotations, and modeled the net cash flow when crop prices and yields, and disease damage was stochastic (a variable process where the outcome involves some randomness and has some uncertainty). This stochastic model also included the option of crop insurance, and the net cash flow was evaluated in a risk framework. The structured approach generated results providing affirmation to existing mitigation strategies while revealing new and meaningful insight.
While more specific results can be found in the full project report, learnings can be summarized as follows:
• In the absence of disease, shorter pulse rotations had higher net cash flow than long rotations (advantage varied by ecoregion).
• A low level of disease and associated damage make longer rotations more economically viable.
• Longer rotations were more profitable with or without crop insurance when risk of disease exists (specifically Aphanomyces).
• Crop insurance did not favour any rotation over another, but it did reduce net cash flow variability due to indemnifying payouts triggered by low crop yields.
• For risk-neutral farmers, seven-year rotations in all regions of Saskatchewan and four-year rotations in the Brown Soil Zone of Alberta had higher average net cash flows.
Based on the findings, with price risk and production uncertainties and across each of the lentil and pea growing regions tested, the results suggest pea and lentil growers should consider adopting agronomically recommended rotations with at least six break years in pulse production when Aphanomyces is present in their fields to maximize economic return.
Portions of this article were extracted from articles written for the POGA Oat Scoop (November 2020 and March 2023) by contract author Pam Yule, Right Angle Business Services.

The sustainability of cropping systems can be improved by increasing diversity and incorporating pulse crops into rotation. Pulses are important in human nutrition as sources of proteins, vitamins, and minerals. Recently, pulse crops have gained a lot of attention as consumers demand a transition towards plant-protein based diets to ensure global food security and address concerns around climate change and the environment. Pulses are well-known for their ability to fix atmospheric nitrogen, thus reducing energy consumption and making them particularly suitable for low-input systems. As a rotational option, they provide a source of diversification to break insect, disease, and weed cycles as well as optimize nutrient management.
Robyne Davidson and her research team at Lacombe have been trialing lupin in their pulse crop plots for the past five years. She has a three-year project funded by Results Driven Agriculture Research (RDAR) and Alberta Pulse Growers (APG) to study the agronomics of lupin production in Alberta. Davidson and her research team moved from Alberta Agriculture and Irrigation to Lakeland College in 2021. Their pulse projects moved with them.
Narrow-leaf lupin is a cool season legume crop native to the Mediterranean area that is grown in many parts of the world and well established in Australia and Europe. The potential for success in certain areas of Alberta is high. As a cool season crop, lupin performs well in temperatures below 25°C and in areas that receive an average of 10 inches (250 mm) of precipitation spread throughout May to July. Drier conditions throughout August promotes timely and even maturity for harvest. Lupins prefer the neutral to slightly acidic soil pH values (5.5-7.0) found across most of central Alberta.
Lupin is a competitive choice for producers as it can be seeded early, has excellent nitrogen fixing abilities, lodging resistance, easy to harvest, no major disease or insect issues, intercropping benefits and adapted to areas of Alberta not suitable to other pulse crops.
“The beneficial effect on subsequent crops reinforces lupin’s suitability for crop rotations,” Davidson explained. “Preliminary research shows lupin has resistance to Aphanomyces euteiches – a devastating pathogen of other pulse crops such as field pea and lentil.”
To ensure success, producers would need to choose clean, well-drained fields as broadleaf herbicide options are currently limited and, despite the large woody root, lupin doesn’t tolerate water-logged conditions for more than a few days. Seeding early and applying pre-seed herbicides would give the crop a competitive advantage and ensure timely maturity.
There are two important lupin species of interest to commercialization companies for growth in Alberta: Lupinus angustifolius (narrow-leaf blue lupin) and Lupinus albus (white lupin). These types are considered domestically bred and are known as ‘sweet lupins’ containing low levels of harmful alkaloids that have been removed for human consumption and livestock feed. Narrow-leaf blue lupin is currently the type of most interest for its suitability to the Alberta climate.
In addition, the agronomics are good, and this type is easier to grow than the white type due to similar seed size and handling practices as field pea. White lupin is harder to handle due to its larger seed size and late maturity. This type, however, is preferred for use in industry and has much potential in the southern area of the province where soil pH is lower, and the season is longer, as long as water isn’t limiting.
There are tremendous prospects for lupin in the fractionation industry where components are separated and used for ingredients in snack foods, non-dairy milk substitutes, high-energy drinks, desserts, pet food, and cosmetics. The crop is high in fibre, low in starch, and very high in protein. Of all pulse crops available to Alberta producers, lupin has the highest percentage of protein, ranging from 32-40%. Field pea, the current crop choice for protein fractionation, averages around 25%, whereas faba bean, the previously highest protein crop, ranges from 28-32%. As a plant-based protein source, lupin protein concentrate has reliable water and oil absorption and high levels of gelation properties for use in many food applications. Lupin is an excellent choice for aquatic feed, and because the protein is so high can be used with great success in livestock feed rations.
The lupin crop has unique attributes that have gained the attention of major commercialization companies and food ingredient corporations. These companies are providing investments and offering grower contracts to assist in market growth and offer incentives to producers to incorporate lupin into crop rotations as an alternative or additional pulse crop to improve cropping systems in this province and western Canada.