Biocontrol of blackleg using carnivorous bacteria

Project Summary

Overview

Infections by plant microbial pathogens can be controlled by the use of other microorganisms. One group of potential biocontrol bacteria are the myxobacteria.

Myxobacteria are a group of bacteria which adopt a “wolf-pack” hunting strategy against other bacteria and fungi. Myxobacteria swarm in groups of thousands of cells towards prey and attack in a coordinated fashion. They lyse and consume their bacterial and fungal prey. Myxobacteria have been investigated for the biocontrol of fungal pathogens of tree seedlings, peppers, fruit, and vegetables. During the course of this project new strains of myxobacteria will be isolated from Manitoban sources.

The research team will determine their ability to attack and kill fungi including Leptosphaeria maculans, the causative agent of blackleg in canola. Myxobacteria are natural inhabitants of agricultural soil and either their application to canola or stimulation of populations in the soil will antagonize Leptosphaeria maculans and other pathogenic fungi. This will be the basis of a biocontrol strategy against blackleg and potentially any other fungal pathogen of canola which will complement existing plant resistance breeding, agronomy, and fungicide treatments.

Purpose

This project will provide a novel potential biocontrol strategy for the control of blackleg on canola. Farmers would be the beneficiaries of the successful completion of this project. Application of a commercial myxobacteria biocontrol product or stimulation of existing myxobacteria populations in agricultural soil would be another tool in a blackleg control strategy, one with better optics than fungicide application. A commercial endeavour could be formed through the production of a myxobacterial biocontrol product.

Objectives

This project will:

1. Isolate various myxobacterial and mycophagous bacteria from soil, sediment, and plant material from Manitoban sources.
2. Identify, using conventional microbiological and molecular genetic techniques, those myxobacterial and mycophagous isolates.
3. Determine whether the isolates can kill or inhibit the growth of filamentous fungi.
4. Determine whether the isolates can kill or inhibit Leptosphaeria maculans.