Canada: Poor quality cereal seed on deck for 2017

Author:  Angela Lovell

Farmers across the Prairies will remember 2016 as the year when they had frequent, above-average moisture right through the growing season, delaying both seeding and harvest in many cases.

All that moisture means there will be some poor quality cereal seed around for the 2017 season, although the quality of pulses like peas and fava beans are good, as are soybeans.

Manitoba wheat seed samples tested last fall from the 2016 crop have an average germination of around 86 per cent, compared to the usual average of 92 to 95. Some samples have tested as low as the 70s and low 80s. Germination in barley samples is similar, averaging around 87 to 88 per cent compared to 93 per cent in a normal year.

In Alberta it’s much the same story, with wheat samples showing an average germination of around 87 per cent.

In Saskatchewan six to seven per cent of wheat samples tested are usually below 75 per cent germination, but this year that number is more like 45 to 50 per cent. The situation is far worse with durum wheat seed in the province. “This is probably the ugliest durum crop we’ve seen in 25 years,” says Bruce Carriere, president of Discovery Seed Labs in Saskatoon. “The average germination on durum wheat samples this year is 65 to 67 per cent. In a normal year we see about seven to eight per cent of durum samples under 85 per cent, and this year it’s 70 per cent that are below that number. Only two per cent are above 95 per cent, the usual germination average.”

Barley seed in Saskatchewan is doing quite well in terms of germination, adds Carriere, but falling numbers on many samples are low, which indicates the seed may not remain stable. Carriere suggests growers test barley samples again in March to ensure that the germination hasn’t declined.

As soybean acres continue to climb in Manitoba, average germination of samples has also been increasing from 82 per cent in 2012 to just over 94 per cent for 2016 samples, said Holly Gelech, president of sales, marketing and client services at BioVision Seed Labs Labs in her presentation about seed quality to the Manitoba Agronomists Conference in Winnipeg in December.

The wet conditions at harvest that are bad for cereals favour soybeans and other pulse crops like peas and faba beans. Soybean are dicotyledons, so they have two seed embryos that hold the reserves needed for germination. If conditions are hot and dry during harvest — as they were the previous two years — the seeds are subject to mechanical damage, which causes abnormal seedlings and reduces germination. In 2016, with rainfall at harvest, soybean crops generally came off with higher moisture content and suffered less mechanical damage, resulting in higher germination potential.

Although not yet as big a crop in Saskatchewan as in Manitoba, soybean seed samples in that province also had good germination levels this year and few disease issues.

Pea seed samples in all three provinces are showing some of the highest germinations in five years, again largely thanks to the moisture at harvest, which prevented mechanical damage. In Saskatchewan, pea samples are showing a higher than normal incidence of ascochyta fungus, which growers can help to suppress with a seed treatment.

Lentils are a huge crop in Saskatchewan, and seed quality is a mixed bad depending on region. Some areas, for example around Kindersley and Rosetown, produced no seed at all. South-central areas have lots of seed, with high germination and low disease pressure. “Lentils need to have some heat stress around late June to early July in order to set seed, and some areas had so much moisture there was no stress, which isn’t normal,” says Carriere. “There will be some good lentil seed around this year but farmers may have to drive to find it.”

Sarah Foster, president and senior seed analyst at 20/20 Seed Labs which has labs in Manitoba and Alberta, says 95 per cent of the samples coming in from Manitoba are testing positive for fusarium graminearum, as are 73 per cent of Saskatchewan samples, and 24 per cent of Alberta samples. “It’s the highest it’s been since 2014,” says Foster. “Part of the reason is that we got both early infection and late infection with Fusarium because of the environmental conditions. We’ve also seen a higher incidence of root rot in barley.”

Fusarium graminearum infection in Manitoba wheat samples tested so far in their lab, says Gelech, have infections averaging 18.5 per cent compared to three per cent in normal years. “We even analyzed one oat sample that was infected at 34.5 per cent. It is a bad year for seed-borne pathogens in Manitoba,” says Gelech.

Disease also plagued Saskatchewan’s durum crop last year, mainly fusarium, not necessarily fusarium graminearum, but other fusarium species that infected the crop in the fall, when wet conditions continued to be a problem.

Issues other than disease are also causing some seed quality issues, but they are all a result of environmental conditions during the harvest season. “In barley, particularly, we saw some pre-sprouting,” says Gelech. “Once the seeds start to sprout, they’re not going to germinate again so we have low germinations in some barley, although not all.”

Gelech says their Manitoba lab is also seeing some frost-damaged seeds from northern areas of the province, as well as some chemical damage from pre-harvest herbicide applications. Chemically damaged seeds may sprout, but seedlings have abnormal and insufficient root development.

On the whole, says Carriere, any Saskatchewan seed crops that came off before the first rainfall in early August are good quality, but anything after that date declines rapidly in quality and value because of seed-borne pathogens like fusarium. Although there should be enough wheat seed to go around for the season ahead, he predicts any wheat varieties that offer some fusarium resistance will sell out quickly.

But durum wheat seed may be a lot harder to find. “This is the second year in a row we have had such terrible durum problems and although seed growers carried seed over for one or two years, most of that is gone already,” he says. “There are going to be a lot lower durum acres in Saskatchewan for sure this year.”

There will likely be more farmers using seed treatments this year due to the high incidence of seed-borne pathogens in seed lots. Carriere says seed treatments have been growing more popular every year and he thinks that may be the reason why fusarium graminearum wasn’t as big an issue in Saskatchewan cereal crops as other fusarium species last season. “This is probably the first year we saw the average levels of fusarium by crop district a little bit lower than usual and I think a lot of that has to do with seed treatments,” he said.

Dormancy and seed stability in question

Labs across the Prairies are also reporting issues with dormancy in cereal crop seed this year. “We’ve had this issue once before in 2007, when the germination was testing really well but the vigour was very poor,” says Foster. “Average germination in wheat this year has been between 85 and 90 per cent, which barely makes the minimum, and tells you that there’s an issue as a result of either immature seed, dormancy, heating or frost, and we’ve had all of them. But when we do a vigour test, even though the germination is hovering around 85 per cent, the vigour is only 60 per cent or less. A textbook case is 90 per cent germination and 80 per cent vigour — you never want more than a 10 per cent spread. When the vigour is this low it means that the germination is definitely going to drop over the next few months.”

The problem is a product of environmental conditions rather than genetics, adds Foster. There are two types of dormancy. One is a result of immature seed that was harvested too soon, and in that situation adding a growth stimulant breaks the seed dormancy. The second type of dormancy is a result of too much moisture, so the seed hasn’t dried down. It won’t rot, but just remains dormant, reducing its potential to germinate.

In fall samples with low vigour that Foster’s lab has retested for clients, germination has fallen by 50 per cent. Most seed labs are recommending that farmers and seed growers retest for germination in the spring or even earlier, and don’t leave it too late to make sure their seed has made it through the winter and is still viable.

“If they haven’t re-tested it already, they should because they need to be sourcing new seed if the quality has declined,” says Foster. “They can’t increase their seeding rates enough to overcome the poor germination because the quality just isn’t there. The seed doesn’t have the components that are necessary for germination to take place.”

Thousand-kernel weight (TKW) is another important test that growers may want to get along with the germination re-test. “Seed size is so important,” says Gelech. “Canola bags come with a TKW already on the package, and kernel count is also very important for soybean due to size variability. In cereals, there is definitely a move towards adding TKW testing to the analysis as customers are targeting specific plants per metre when seeding.”