Agri-inovation Program

Industry-led research and development stream

Ten Activities

1. ACTIVITY I: Improving canola resistance against blackleg disease through the incorporation of novel resistance genes sourced from B. napus, B. rapa, B. oleracea 
2. ACTIVITY II: Identifying novel resistance genes from canola relatives and developing canola germplasm with multiple resistance genes sourced from B. nigra, B. juncea, and B. carinata 
3. ACTIVITY III: Genome-wide association mapping of quantitative resistance against Blackleg in B. napus 
4. ACTIVITY IV: Transcriptomic analysis of the Leptosphaeria maculans – (blackleg-canola) interaction to identify resistance genes in canola and avirulence factors in L. maculans 
5. ACTIVITY V: Blackleg: Durable blackleg resistance stewardship through knowledge of blackleg pathogen population, resistance genes and crop sequence towards the development of a cultivar rotation in the Prairie Provinces 
6. ACTIVITY VI: Blackleg: Investigating the resistance (R-gene) durability of canola cultivars and the emergence of virulent blackleg isolates in farmers’ fields 
7. ACTIVITY VII: Rapid field diagnostics of the blackleg pathogen races through the identification of pathogen avirulence (Avr) genes and the development of Avr-specific markers 
8. ACTIVITY VIII: Blackleg: Development of a blackleg yield loss mode and assessment of fungicide resistance in western Canadian populations of Leptosphaeria maculans 
9. ACTIVITY IX: Sclerotinia: Characterization of defense genes underlying quantitative resistance loci (QRL) to Sclerotinia stem rot in Asian Brassica napus and transfer of resistance to Canadian spring type canola 
10. ACTIVITY X: Sclerotinia: Resistance to Sclerotinia sclerotiorum necrosis-inducing proteins in canola 

Activity I

Improving canola resistance against blackleg disease through the incorporation of novel resistance genes sourced from B.napus, B.rapa, B.oleracea 

Lead Researcher: M. Hossein Borhan, AAFC 

The Challenge: Blackleg populations continue to rapidly evolve, threatening the success of resistance genetics available in commercial canola varieties. New sources of resistance genes against blackleg are required. 

The Project: To identify new major-resistance genes for blackleg by phenotypic screening Brassica napus, B. rapa & B.oleracea against six Leptosphaeria maculans strains. Evaluation of field resistance will be tested in a blackleg nursery with the disease response evaluated at the cotyledon and adult plant stages. 

The Results: The genetic profile of over 1100 accessions of Brassica were generated from six Lm isolates (64.3% containing Rlm3 as a major gene). Two B.napus lines with novel race-specific resistance genes were identified, with one line supporting a novel broad-spectrum race-specific gene against blackleg disease. 

Grower Impact: Due to the rigorous screening among B.napus and B.rapa, canola breeding programs can work on providing new sources of resistance genes against blackleg in commercial canola varieties. 

Activity II

Identifying novel resistance genes from canola relatives and developing canola germplasm with multiple resistance genes sourced from B.nigra, B.juncea, and B.carinata 

Lead Researcher: Genyi Li & Dilantha Fernando, University of Manitoba 

The Challenge: To develop new highly blackleg resistant cultivars, it is crucial to understand R gene sequences. The blackleg resistance genes on chromosome N7 has been studied for over three decades, but due to its complexity, none of the genes on N7 have been sequenced. 

The Project: To create germplasm with novel blackleg resistance genes from canola relatives to increase resistance and durability against blackleg. 

The Results: Successful at sequencing chromosome N7, producing more than 10 advanced backcrossing lines which have all showed excellent resistance to aggressive isolates of the blackleg pathogen. 

Grower Impact: Furthering the understanding of R genes within canola relatives allows for an increased genetic package available in commercial canola varieties against blackleg. 

Activity III

Genome-wide association mapping of quantitative resistance against Blackleg in B. napus 

Lead Researcher: M. Hossein Borhan, AAFC 

The Challenge: Adult plant resistance (APR) is race non-specific which increases durability against the evolving pathogen races, but little is known about how it works within Brassica napus. 

The Project: To identify genetic markers for controlling APR to blackleg and gain a better understanding of its genetic architecture in B.napus. 

The Results: Successfully identified markers that control APR and defined its durable interaction against blackleg. 

Grower Impact: Understanding Adult Plant Resistance allows seed companies to incorporate quantitative resistance more effectively, resulting in a more robust resistance against blackleg in commercial canola cultivars. 

Activity IV

Transcriptomic analysis of the Leptosphaeria maculans – (blackleg-canola) interaction to identify resistance genes in canola and avirulence factors in L.maculans 

Lead Researcher: Richard Bélanger, University of Laval 

The Challenge: Without an understanding of canola’s physiological defense response, blackleg genetic resistance will continue to breakdown. 

The Project: Analyze canola’s defense response(s) towards blackleg disease development at a molecular level and evaluate the potential role of aquaporins during biotic stress conditions in resistant and susceptible genotypes. 

The Results: A total of 43 effector proteins were identified when comparing the compatible and incompatible interactions; 15 expressed during the necrotrophic phase of the fungus, and 28 in the biotrophy phase.  

Grower Impact: By better understanding the canola plant, research can now be directed to producing stress-tolerant canola cultivars which could potentially mitigate environment and disease pressure. 

Activity V

Blackleg: Durable blackleg resistance stewardship through knowledge of blackleg pathogen population, resistance genes and crop sequence towards the development of a cultivar rotation in the Prairie Provinces 

Lead Researcher: Dilantha Fernando, U of M 

The Challenge: Pathogen races continue to shift across the prairies, causing resistant cultivars to become susceptible to L.maculans. 

The Project: To develop, establish and recommend a blackleg mitigation guide to growers based off crop history, R-genes, initial pathogen population, and growing conditions.  

The Results: Presence of blackleg was found in all fields monitored, but the pathogenic variability differed between Manitoba, Saskatchewan, and Alberta. Variability in fields can be contributed by genetic drift and/or selection pressure. Commercial varieties most commonly contain Rlm1 and Rlm3, therefore deploying Rlm6, Rlm7 and Rlm4 could be highly effective for blackleg control. Lengthening rotation has shown to be very effective, with a potential of 5bu/ac yield increase (in 2017). 

Grower Impact: Growers may now select canola varieties based on major gene resistance, which will contribute to the successful management of blackleg. Additionally, increasing rotation length has been shown to not only decrease the pathogen population in the field but in some cases increase canola yield by 5 bu/ac (in 2017). 

Activity VI

Blackleg: Investigating the Resistance (R-gene) durability of canola cultivars and the emergence of virulent blackleg isolates in farmers’ fields 

Lead Researcher: Dilantha Fernando, U of M 

The Challenge: Due to the variable durability among blackleg resistant cultivars, the emergence of virulent isolates in farmers’ fields has the potential to increase. 

The Project: To assess the impact rotation has on the rate of pathogen virulence change in L.maculans, and to advise which cultivar to use based on gene durability, and when. 

The Results: Rlm3 presence in fields decreased in 2017 compared to 2014, 2015 and 2016. Change of L.maculans genes from avirulence to virulence can occur in one cropping system due to point mutation. As such, knowing the likelihood of major gene resistance breakdown when introduced into virgin fields is crucial. Genes durability ranked: LepR3 > LepR1 > Rlm2 > Rlm4 > Rlm3 

Grower Impact: Producers can now choose varieties with major gene resistance that are durable to the specific blackleg races in their field, prolonging the effectiveness of blackleg resistant cultivars. If the success of a resistant cultivar decreases over time, lengthening crop rotation may encourage the pathogen population to shift back to where those resistant cultivars become effective again. 

Activity VII

Rapid field diagnostics of the blackleg pathogen races through the identification of pathogen avirulence (Avr) genes and the development of Avr-specific markers 

Lead Researcher: M. Hossein Borhan, AAFC 

The Challenge: Selection pressure through blackleg resistant varieties cause the emergence of new virulence L.maculans isolates. Knowing which specific races are in the field would help in managing the blackleg disease through choosing proper major gene resistant varieties. 

The Project: Develop a marker-assisted genotyping as a fast and accurate approach for monitoring changes in L.maculans population in canola fields. 

The Results: The PCR biomarkers were developed and shared with public and private pathology labs across western Canada. 

Grower Impact: Growers can send their canola stubble into pathology labs for specific race identification if they detect high levels of blackleg in their field. Knowing which race is in their field can help them choose an appropriate canola variety with its associated major gene resistance. 

Activity VIII

Blackleg: Development of a blackleg yield loss mode and assessment of fungicide resistance in western Canadian populations of Leptosphaeria maculans 

Lead Researcher: Stephen Strelkov, U of A 

The Challenge: With increase presence of Leptosphaeria maculans across the prairies in recent years, understanding the relationship between blackleg disease severity and canola yield loss is essential. Fungicide resistance and best management practices will be considered when analyzing blackleg genetic resistance breakdown in commercial cultivars.  

The Project: Develop a yield-loss model associated with the severity of blackleg on canola, and asses fungicide resistance across the prairies of L. maculans. 

Grower Impact: By following best management practices, including an increased rotation and the use of blackleg resistant genetics, the risk of blackleg severity can be greatly reduced. 

Activity IX

Sclerotinia: Characterization of defense genes underlying quantitative resistance loci (QRL) to Sclerotinia stem rot in Asian Brassica napus and transfer of resistance to Canadian spring type canola 

Lead Researcher: Lone Buchwaldt, AAFC 

The Challenge: If breeders can develop canola varieties with high resistance to sclerotinia, the reliance on unreliable fungicide predictor models could be irrelevant. In turn, having resistant genetics could provide benefit to growers, consumers, and the environment. 

The Project: To identify molecular markers linked to sclerotinia resistance and their defense genes, and to transfer sclerotinia resistance to open-pollinated spring-type canola. 

The Results: With four germplasm lines and two pre-breeding lines, breeders should be able to transfer the source of sclerotinia resistance to new varieties. Through molecular markers, 17 isolates were identified in Western Canada which represent the variability of the pathogen on the prairies. The “stem test” was developed to evaluate canola cultivars with sclerotinia resistance claims.  

Activity X

Sclerotinia: Resistance to Sclerotinia sclerotiorum necrosis-inducing proteins in canola 

Lead Researcher: Dwayne Hegedus, AAFC 

The Challenge: Currently, the only sclerotinia resistant sources for Canadian breeders are winter type lines with partial resistance to stem rot.  

The Project: Develop spring-type canola with one or more highly effective stem rot resistance genes to oppose the establishment of necrotic lesions specifically by S.sclerotiorum, that contributes to lodging and crop loss. 

The Results: Increased comprehension of how S.sclerotiorum causes disease as the entire suite of genes expressed during each stage of infection of canola was cataloged. New proteins that cause necrosis were identified. 

Grower Impact: Research can now continue to analyze how necrotic patches on canola are encouraged by S.sclerotiorum and possibly inhibit them from developing for future commercial cultivars. This would allow the plants to stay strong and avoid crop loss due to lodging and premature ripening.