Disease defence starts with seed testing

Editor's note: This article was updated in 2024 with additional content.

Direct seeding, shorter crop rotations, earlier seeding — they’re all management practices that have the potential to help growers harvest higher yielding, more profitable cereal and pulse crops. But each practice comes with some level of risk. The first step in defending your crop against these challenges is to take a good look at the seed.

​​Weather and harvest conditions will play a key role in determining seed quality and disease levels in the next season. Excessive moisture and high humidity can be a recipe for in-crop disease pressure, which leads to high levels of seed-borne disease, lower germination rates and poorer vigour.

Shad Milligan, Syngenta Seedcare technical lead, recommends getting a seed test. The results, he says, will give you a good measure of germination and vigour of your seed lot, as well as identify potential seed-borne pathogens.

The test can be performed at an accredited seed lab after harvest and prior to cleaning seed. A list of accredited seed labs is available from the Canadian Seed Institute.

Germination test results will help to determine seeding rates and optimize stand establishment, so you can be confident the seed lot chosen will come out of the ground strong.

The lab can also conduct fungal diagnostics to identify potential seed-borne pathogens and estimate the percentage of seed that is affected by specific diseases. Detecting disease at this stage allows you to make informed decisions about seed lots and select the appropriate seed treatment to manage disease.

Seed and soil-borne diseases

With a disease like seed-borne Fusarium, we want to plant seed that has low levels of infection to start with if possible. For seed infections, seed treatment plays an important role preventing seed rot or seedling blight as the seeds begin to germinate after planting. Since Fusarium spp. can also be soil-borne, causing damping-off or root rot, seed treatments will also minimize the impact on the crop and maintain a healthy seedling.

It’s also important to understand soil-borne disease challenges when assessing seed. For example, if a farm has a history of Pythium spp. or Rhizoctonia spp., it should also be considered when assessing seed quality and seed treatment needs.

The seed, says Shad, is really a food source, so once it is in the ground there’s a lot of pests that want to feed on that seed and emerging plant. The type of pest depends on the conditions when planting.

For example, soil moisture management (i.e. keeping crop residue from the previous crop) and choosing to direct seed saves time, but means you’re likely seeding into cooler, moist soils where Pythium can thrive.

“The success of a crop largely depends on the seed you put in the ground,” Milligan says. “Knowing the quality of that seed will help determine what other investments are required to reach your yield goals.”

For more information about seed testing or seed treatment, contact our Customer Interaction Centre at 1-87-SYNGENTA (1-877-964-3682).