Author: Lisa Guenther
Durum in Saskatchewan has been a “complete disaster” for the third year running.
That was Bruce Carriere’s grim assessment at the Bayer SeedGrowth Solutions Expo in Saskatoon this spring. Carriere, president of Discovery Seed Labs in Saskatoon, said Saskatchewan durum growers usually have a year carry-over of seed.
“They used that last year,” he said.
Early estimates predicted a drop of 20 to 25 per cent of durum acres in Saskatchewan because of the lack of good seed. He’d recently heard that number might be higher.
Carriere said average Sask durum germination is 71.4 per cent. “The vigour is down in the low 60s. Sixty-two per cent of the durum germs are under that 85 (per cent germination) mark.” Normally about nine per cent of the durum falls below the 85 mark, he added.
Barley’s average germination was higher, but 20 per cent of Saskatchewan’s samples fell below 85 per cent. Carriere said germination was falling off because of chipping and sprouting. Vigour came in at 69 per cent. High moisture from last fall’s harvest was behind the falling germ and vigour, he added.
Saskatchewan farmers planning to grow malt barley might have trouble lining up good varieties if they hadn’t done that by March, he added.
Wheat seed isn’t looking great, either. There are large geographies lacking seed at that 85 per cent germination level, said Holly Gelech, manager of business development at BioVision Seed Labs in Sherwood Park, Alberta.
Gelech and Carriere both noted high disease levels in submitted cereal samples. Gelech saw a spike in storage fungus, specifically aspergillus and penicillium, this year. “Now this is something we typically don’t see unless a grain or seed goes into the bin during high moisture and is not monitored.”
But the big problem this year is fusarium. Generally, more samples are testing positive for graminearum than usual, and seed lots tend to have more severe infections than previous years.
Seed labs also test for other fusarium species, and report those numbers as fusarium totals. Carriere explained poor harvest conditions lead to high fusarium totals. Saskatchewan’s durum samples ranged from zero to 92 per cent total fusarium infections, and the average was 18.9 per cent, topping the recommended 15 per cent limit for seeding.
“Those numbers are a little scary,” he said.
The bottom line is that with all the disease out there from last year, “the land is now re-inoculated for 2017,” said Gelech.
Should you use that seed?
Gelech had several suggestions for farmers trying to decide whether to use their farm-saved seed. The first step is to send in samples in the fall for germination tests and to find out what types of fungal pathogens are present. She also suggested a cool stress test for farmers planning to seed into cool soils.
Farmers should then go through the provincial benchmarks to decide whether to use that seed. Guidelines vary by province, and Alberta has legislation regarding fusarium-infected seed. A certified grower will only sell seed that meets the 85 per cent germination benchmark, Gelech said.
In a normal year, the guideline for most Saskatchewan rural municipalities is to treat and use anything with zero to five per cent graminearum infection. But that’s not a hard-and-fast rule, Carriere said.
“If I have a 95 germ, and 6.5 per cent graminearum number, I’m probably going to use it. Especially this year. You’d be hard-pressed to find much better,” he said. Saskatchewan durum growers will have to be a little more flexible with total fusarium numbers as well, he added.
If a seed lot is simply too diseased to work with, Gelech suggested figuring out what quality is like in the region. While many areas are short on good seed, there are other areas “that are actually quite good this year,” she said.
Farmers can also carry over that seed until 2018. Doing so should drop disease levels by about half, said Carriere. Carrying it to spring 2019 should drop disease by about half again, he added. But he cautioned that when seed has a severe graminearum infection, the germ can also fall. Gelech said that farmers should also consider whether seed will store well, and whether drying might have affected the germ.
Before spring seeding, Gelech recommended reconfirming seed quality with germ testing and vigour testing, if applicable. She also suggested a TKW test.
Carriere also warned that farmers shouldn’t use fuzz count as a guideline for seed. There’s no correlation between fuzz count and the percentage of seed infected, he said.
Protecting the 2017 crop
Carriere recommended farmers use a seed treatment if any fusarium is detected, no matter the soil conditions.
In 2016-17, BioVision ran a trial with over 100 submitted wheat samples from across Western Canada. BioVision split each sample into bare seed and treated seed. The bare seed had an average germination of 89.6 per cent. Custom-treated seed saw a five per cent germination bump.
Gelech said they also did vigour tests on the treated and untreated seed, to mimic field conditions. Bare seed germ was 87.6 per cent, while treating seed bumped the germ to 91.2 per cent.
Cereal growers can also try to improve fungicide application timing. Carriere suggested increasing seeding rates to reduce tillers. Tillers flower at different times than the main stem, making it more difficult to stage the fungicide.
Gelech suggested farmers find a nearby weather station, or get their own, and follow models that predict disease development. Fusarium head blight infects susceptible crops during flowering, if conditions are moist.
“If you have a relative humidity of 80 or 90 per cent, that’s dynamite for pathogen development,” she said.