Expanding BnVQs (Valine-Glutamine) gene family against Sclerotinia sclerotiorum in canola
Sclerotinia sclerotiorum, which causes Sclerotinia Stem Rot (SSR) or white mold diseases, is a devasting necrotrophic pathogen that infects a broad range of plant species, including soybean, cotton, sunflower, and canola. Sclerotinia stem rot disease is a major disease distributed across major canola/rapeseed/oilseed rape growing regions. This soil-borne disease is one of the major diseases in canola-growing regions in Canada.
Comparative analysis of Verticillium longisporum lineages in the Canadian Prairies: Safeguarding canola production
The escalating frequency of drought conditions in the prairies is anticipated to exacerbate the prevalence and severity of Verticillium stripe disease. As a result, the threat posed by Verticillium stripe disease looms larger over canola production in the Canadian Prairies, necessitating diligent monitoring and proactive management strategies to safeguard crop yields and economic sustainability. Therefore, it is imperative to gain a comprehensive understanding of the genetic diversity and population structure of V. longisporum lineages prevalent in the prairies.
Land Application of Spent Filtration Earth From Canola Oil Production to Improve Soil Properties
About 2 million metric tonnes of spent bleaching/filtration earths from vegetable oil refining are produced worldwide every year. The canola crush oil processing industry in western Canada creates significant amounts of spent bentonite- based filtration earth from the crushing of 10 million tonnes of canola. New crush facilities being built or expansion of crush capabilities by companies including Viterra, Richardson, Cargill, and others will increase the amount of spent filtration earth produced as a by-product of the crush industry. The spent bleaching/filtration earth material left from vegetable oil refining has traditionally been disposed of in landfills, but this is an undesirable and expensive practice, and many landfills will no longer accept bleaching earth from vegetable oil refining. The high oil content of the material when stockpiled in one place can lead to problems with spontaneous combustion. Recycling through extraction and production of biodiesel from the oil left behind in the clay, making briquettes or clay tiles, among other industrial uses, have been proposed as alternative uses for the material.
New pre-breeding tools for canola – facilitating canola improvement by accessing diploid variation
Access to genetic diversity is key to the success of crop breeding programs and, in this regard, the canola gene pool is particularly limited. This is due to the natural history of amphidiploid Brassica napus (AACC) being formed from an interspecific hybridization event between its diploid progenitor species B. rapa (A genome) and B. oleracea (C genome). This hybridization event(s) occurred recently (ca. 2000 years ago) meaning that there has been limited time for mutations and introgressions to occur and natural selection to increase the frequency of alleles required for further crop improvement. Canola breeders use a range of strategies to overcome this deficiency including mutagenesis, wide genetic crosses and crosses involving wild relatives.
In vitro culture of Plasmodiophora brassicae
Plasmodiophora brassicae is an obligate pathogen so must have a host to complete its life cycles and, by definition, cannot be grown in pure culture. The pathogen lives within the cells of its host throughout most its life cycle. Resting spores are produced in infected roots and are released into the soil as the roots decay. These represent the only source of pure pathogen available. However, when trying to get ‘clean’ cells for sequencing and other research, the P. brassicae material is generally contaminated with genes from plants and soil microbes which causes problems. A method to grow pure cultures of cells of P. brassicae, outside of the host, would be very useful for many types of research, and especially as a tool for selecting clubroot resistant canola lines, and advancing breeding canola for clubroot resistance.
Methods to isolate and maintain clubroot for improved resistance screening and labeling
Although planting resistant canola varieties is the primary approach for clubroot management, a growing number of clubroot pathotypes has emerged in recent years that can overcome host resistance, posing a significant challenge for growers. As such, it is critical to identify novel sources of resistance that are effective against these emerging strains of the pathogen. The identification of and breeding for resistance relies on testing host lines by inoculating them with the most prevalent and/or significant clubroot pathotypes on the Prairies.
Investigating the conditions favoring Verticillium stripe development and yield losses in canola
Verticillium longisporum survives as microsclerotia on crop residues and in the soil for up to 20 years, but also has been reported on plants in previously uninfested areas. As a monocyclic vascular pathogen, it may also be capable of invading seeds. V. longisporum was recovered from seeds in up to 13% of greenhouse-grown inoculated plants. Seed infection may impact seedling establishment, but even very low levels of seed transmission may be important when there is the potential to introduce the pathogen into a new area.
Clubroot Pathotype Evaluation and Monitoring
Since 2013, clubroot has been diagnosed in at least 3,894 individual fields across Alberta, with dozens of cases also reported in Saskatchewan and Manitoba. The management of clubroot is challenging, as P. brassicae produces large numbers of long-lived resting spores that can cause severe yield losses in susceptible hosts. Genetic resistance is the most effective tool for disease control, but the emergence of new pathotypes that can ‘break’ or overcome host resistance indicates that this tool is at serious risk. Forty-three pathotypes of P. brassicae have now been identified in Canada, 25 of which are virulent on at least some clubroot-resistant canola varieties. Rapid shifts in the virulence of the pathogen, combined with the continued emergence and spread of resistance-breaking pathotypes, indicate a need for proactive disease management and resistance-breeding efforts.
Volatile-based trapping and management of flea beetles
Striped and crucifer flea beetles are the most significant insect pests of canola on the Canadian Prairies. Currently, >99% of canola acreage is grown from insecticide-treated seed, and even then, foliar insecticide applications are often required under high flea beetle population densities. Current monitoring for flea beetles involves in-field scouting from canola emergence through the third true-leaf stage, after which canola can tolerate feeding damage. Plants are examined for typical “shot-hole” and stem-feeding damage and ranked on a 0-100% damage scale. The current recommended action threshold is set at 25% damage.
A comprehensive survey of Verticillium stripe and establishment of a disease nursery in Morden MB
Verticillium stripe has recently become one of the most important diseases of canola in Canada. Verticillium longisporum appears to prefer cruciferous hosts and poses an increasing problem to canola and oilseed rape production. Plant disease nurseries play a vital role in safeguarding agricultural productivity and global food security.
Tracking the movement of flea beetles across the Canadian Prairies
Striped and crucifer flea beetles are chronic pests of canola grown on the Canadian Prairies and as a result over 99% of canola seed is treated with a neonicotinoid insecticide. The flea beetles are known to differ in their tolerance to the neonicotinoids with striped being more tolerant than crucifer flea beetles. Our current project (Ag Funding Consortium: 2021F062R) has found potential differences in the tolerance of both flea beetle species to the neonicotinoid seed treatments depending on collection region. In addition, the two species have differences in their overall physiology in terms of cold temperature tolerance (striped emerge early in the spring) and flight ability (crucifer flies more actively than striped). These differences may affect the overall distribution of flea beetles within and across regions on the Prairies and have implications for management.
Population dynamics and monitoring programs for midges attacking canola
Two species of midge pose a threat to canola production in western Canada. Swede midge is invasive to eastern Canada where it has caused significant economic yield losses. Thus far, swede midge has not established in western Canada, but its geographic range is expanding westward from the northeastern United States. Swede midge could have a devastating impact on the canola and horticultural industries in western Canada. If swede midge continues to disperse westward, early detection will be key to attempting its eradication and preventing it from becoming an established pest in western Canada that requires management using insecticides or other inputs.
