Seed quality a soybean concern

FOND DU LAC – Because of how weather affected the quality of seed soybeans that were harvested in 2018, growers need to carefully check the seed tags this year for the promised germination rates of those seeds, Extension Service soybean and small grains specialist Shawn Conley warned at the 2019 agronomy update meetings.

Instead of germination percentages well into the 90s, don't be surprised if there are seed lots from most if not all seed companies at closer to 85 percent this spring and even at 82 percent or less with a price discount, Conley advised. He pointed out that there would not be a replant privilege at that low percentage.

Seed protocols

Although he hasn't obtained as much information as he'd like from the seed companies, Conley expects that many of them will run a third germination test of their seed in addition to those taken shortly after harvest and as the seeds are prepared for sale and delivery.

Because of how fungicide treatments improve germination, Conley urges all soybean growers to insist on such treatment this year although it will cost a bit more at a time when growers are looking to cut production costs. That will mean lots of colored seed this year, he observed.

Conley is particularly concerned about the presence of the phomopsis fungus on seeds. It causes an infection that affects the early stage growth of plants.

Xtend expansion

After accounting for about 30 percent of the soybean acres in Wisconsin during 2018, Conley expects nearly a doubling of soybeans with the Xtend trait in the state this year. That trait allows for application of dicamba herbicide, which is particularly effective for control of waterhemp, he pointed out.

Another reason for an increase in the Xtend trait varieties is the likelihood that more service suppliers are ready to apply dicamba, Conley remarked. He also reported that white mold was a problem with Xtend varieties in 2017 but not in 2018 and that, except in the far north, Xtend varieties out yielded the others in the Extension Service's trial plots last year.

Conley emphasized that some soybean fields are already flowering before the summer solstice (June 21), which had not been the case in the past. He noted that a new federal regulation limits the application of dicamba to before soybeans start to flower. In recent years, dicamba applications have resulted in severe damage to non-tolerant crops in several states, not including Wisconsin.

Soybean outlook

After soybean acres exceeded those for corn for the first time in the United States in 2018, Conley expects a cutback of 5 to 8 percent (a minimum of 4 million acres) this year. That's although China, the major importer of US soybeans before recent tariff fights, has approved two more transgenic traits for its imports, along with two for canola and one for corn, he indicated.

A question yet to be answered in early 2019 is how agricultural lenders would lean in approving loans for growing soybeans or corn this year, Conley observed. Recent national estimates suggest an increase of about 3 million corn acres this year, he noted.

Based on the 100-bushel per acre yield of one variety in the trial plot at East Troy in 2018, Conley said this indicates the genetic yield potential of soybeans. He noted that the state on-farm average yield was 51 bushels in 2018 while the trial plot at Lamartine in Fond du Lac County averaged 71 bushels with a range of 53 to 82 bushels per acre.

Small grain updates

For winter wheat growers, Conley advised close attention to plant and tiller numbers this spring because of the many late planting dates last autumn. He said shallow planting is a major problem with the crop because this deters the development of sub-crown intermodes that are essential for plant growth and health.

As needed, don't hesitate to apply nitrogen to wheat, Conley continued. The returns will be an increased grain yield, a greater amount of the straw which commands a strong price, and less of the DON pathogen, he stated.

The Feekes 5 growth stage (just before the appearance of the seed head) is the deadline for the application of dicamba to control weeds in wheat, Conley emphasized. If a fungicide is needed for an outbreak of head scab, wait until there is a good percentage of flowering, he advised.

Conley said downy mildew hasn't been a problem in Wisconsin's wheat since 2010. For the limited number of acres of oats still being grown in the state, he suggested a fungicide application both to control crown rust and to protect standability.

At a per acre planting rate of about 800,000 seeds, about one-half of the ideal rate for early planted winter wheat, Conley has a research plot on hybrid winter rye for both forage and grain harvest. For small grains, he noted that Wisconsin farmers are growing a total of about 500,000 acres of wheat, oats, and barley per year.