Treating seed infected with fusarium won’t stop the infection, but it could get your crop off to a good start
Farmers with fusarium-infected grain may be considering seeding it instead of selling it. Others may have a hard time finding fusarium-free seed. Treating seed won’t reduce the fusarium head blight in the next crop. But, if done right, it can help infected seed get a good start.
“When you use a seed care product, what you’re doing is helping the plant get up and grow and stopping those seed-borne diseases. But basically you’re not going to stop the infection coming from last year’s stubble or last year’s residue or the spores that are floating in from your neighbour’s field at heading time,” says Richard Marsh, cereal specialist with Syngenta.
Guidelines for infected seed
Saskatchewan Agriculture’s website offers guidelines for farmers dealing with diseases such as fusarium in their seed lots. When looking at the guidelines, farmers need to take into account availability and cost of disease-free seed, seed treatment costs, typical weather patterns and disease pressure for their areas, fungicide availability, scouting practices, and the cereal variety being grown.
Ideally farmers should buy pedigreed seed from areas free of fusarium graminearum. Federal regulations don’t require certified seed to meet standards for fusarium infections so farmers should see a lab certificate, especially when buying seed from an area where F. graminearum is established.
If farmers need to use infected seed, it should be tested for germination. Lots with poor emergence should not be seeded. Farmers may also want to have infected seed lots tested for vigour to see how the seed performs in less than ideal conditions. Damaged, sprouted, and immature seed can deteriorate over the winter. It’s worth re-testing such seed for germination in the spring.
Farmers in regions where F. graminearum isn’t established should avoid using seed with F. graminearum. Though there isn’t any compelling evidence that using infected seed increases fusarium head blight in that area, more research is needed on seed-borne fusarium.
If F. graminearum is established in the area, Saskatchewan Agriculture suggests using seed with no more than five per cent F. graminearum. Seed lots with two to three per cent or higher F. graminearum should be treated prior to seeding.
Seed infected by other types of fusarium is likely safe to plant if less than five per cent of the seed is infected, and if F. graminearum is not present. If five per cent or more of the seed is infected, untreated seed may suffer from significant seedling blight.
Saskatchewan Agriculture’s website suggests farmers producing breeder or select seed, along with organic farmers, be particularly cautious with infected seed.
Alberta has not had fusarium head blight outbreaks caused by F. graminearum. Trace levels of the fungus have been found in the province, mainly in irrigated areas. According to the Alberta Fusarium Graminearum Management Plan, imported grain intended for seed must be tested and found free of F. graminearum, and treated with a registered fungicide.
Treatment application crucial
Syngenta offers a couple of options for cereal seed treatment. In 2013, they’ll be selling Cruiser Max Vibrance Cereals and Vibrance XL to treat seed-borne fusarium. Syngenta also sells Proseed to farmers in areas with high fusarium levels. Proseed treats seed and soil-borne fusarium.
Application is critical to seed treatment. If farmers are applying seed treatments themselves, applying the right rate to the seed is important. But covering every seed is just as important, Marsh says.
Marsh says farmers can talk to a seed care specialist that works with the company where they purchased the product. Specialists can help calibrate and set up seed treating equipment to get 100 per cent coverage.
“You can use the best seed care in the world and if you don’t get good coverage, you’re not going to be happy with the results.”