Biosecurity refers to a series of management practices designed to prevent, minimize, and control the introduction, spread and release of plant pests. These include insects, nematodes, weeds, molluscs, bacteria, fungi and viruses.
Biosecurity is something that livestock and horticulture producers have used for years to keep diseases from spreading to their barns, greenhouses and orchards. It is time for broad-acre crop producers to think biosecurity, too.
Introduction and spread of pests can reduce profitability due to (1) reduction in productivity or quality, (2) increased costs for management/control or (3) trade barriers.
Biosecurity is to avoid bringing a pest to the farm (bio-exclusion) and to contain it if/when it does arrive (bio-containment).
Canola pests that can be avoided or contained with biosecurity include clubroot, verticillium stripe and weeds. Other significant crop pests of the Canadian Prairies that can move with moving soil are aphanomyces (aphanomyces root rot of pea and lentil), phytophthera (phytopthera root rot of soybean) and nematodes.
How to be biosecure?
Soil-borne pests move when soil moves. What is the best way to prevent the spread of clubroot? Answer: Remove soil from equipment before leaving a field.
One seeding tool and tractor could easily pick up 600 pounds of soil in muddy conditions. One hundred pounds of soil from central Alberta could have billions of clubroot spores which, if this soil were spread evenly, could lead to yield-damaging levels of clubroot across a whole farm in one year.
Step 1: Rough cleaning of equipment removes 90-95% of soil and spores.
Step 2: Washing with compressed air or a pressure washer brings that up to 99%.
Step 3: Mist-on disinfectant can take that to 99.9%.
Disinfectants must be on the machinery for 20-30 minutes to be effective. Bleach provides the best combination of effectiveness, widespread availability and cost.
While it may not be practical to do all these steps between each field, a realistic biosecurity plan on the farm could look like this:
Step 1: Kicking dirt off openers removes around 40% of the soil on equipment
Step 2: Knocking loose dirt off the tractor removes around 30% of the soil on equipment.
Step 3: Use a clean exit. Folding up and traveling to this clean exit can reduce soil by another 10%, for a total of 80% risk reduction for these three steps.
“It’s OK if you can’t do everything. It’s not OK if you do nothing.”
–This is based on a presentation “Biosafety for field crops” by Mike Harding with Alberta Agriculture.