Comparative analysis of Verticillium longisporum lineages in the Canadian Prairies: Safeguarding canola production

Term: 3 years, beginning 2024
Status: Ongoing
Researcher(s): Zhongwei Zou, Wilfred Laurier University; Harmeet Singh Chawla, U of M
SaskCanola Investment: $185,150
Total Project Cost: $370,300
Funding Partners: WGRF

Objective

1. Molecular and morphological Characterization of the V. longisporum strains collected from canola growing regions in prairies. 

2. Assessment of pathogenicity and virulence of different V. longisporum populations on canola genotypes commonly grown in prairies. 

3. Determine the genetic diversity and population structure of V. longisporum population. 

4. Development of KASP markers for better characterization of V. longisporum populations prevalent the prairies. 

5. Characterize the genetic mechanisms of disease progression in canola plant. 

Project Description

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.

Currently, V. longisporum is broadly categorized into three distinct lineages: A1/D1, A1/D2, and A1/D3, with A1/D1 exhibiting the highest pathogenicity towards canola. However, this classification system is based solely on the analysis of five genomic loci, namely the ribosomal internal transcribed spacer (ITS) region, actin (ACT), elongation factor 1-alpha (EF), glyceraldehyde-3-phosphate dehydrogenase (GPD), and tryptophan synthase (TS). It is important to note that such a limited number of genomic regions may constrain our ability to fully comprehend the genetic diversity within this species and identify unique genomic loci that could play a pivotal role in controlling V. longisporum's pathogenicity. For instance, Harting recently demonstrated the presence of a lineage-specific 20 kb genomic region that significantly reduces the pathogenicity of V. longisporum in Brassica napus. This significant finding emphasizes the necessity for a comprehensive study focused on identifying and characterizing different lineages of V. longisporum using whole genome sequencing, as opposed to relying on a limited number of genetic loci. Therefore, the primary objective of this project is to identify the most prevalent V. longisporum populations in the prairies and evaluate the pathogenicity of these populations on canola cultivars currently cultivated in the region. Additionally, the project aims to conduct an extensive analysis of the genetic diversity within V. longisporum populations in the Canadian Prairies.