• By Angela McClure •
Most farmers had their fair share of seed quality issues during fall 2018, including many seed bean producers. The commercial seed supply is expected to be affected some by weathering at harvest, with severity depending on maturity group and field location.
In most years, a typical soybean bag has a germination percentage of about 85 percent. Tennessee requires all commercially sold soybean seed to have a minimum seed germination percentage of 75percent; however, there is a variance allowed on seed germination of 9 percent.
This means if I ran my own germ test and achieved 66 percent or greater germ, a 75 percent germ bag meets minimum quality standards for Tennessee. In most years, the actual germ is higher than the tagged germ.
But with quality issues on the rise, be advised that the actual germ of some products may be much closer to the tagged germ amount. Additionally, seed quality of a lesser quality bean would be expected to decline at a faster rate between now and May or June, further reducing germination potential.
(During a recent Mississippi Crop Situation Podcast, University of Arkansas Extension soybean specialist Jeremy Ross said the Arkansas Plant Board had been rejecting a significant number of soybean seed lots because of poor germ.)
■ Be aware of germination percentages on seed containers
■ Later maturity group varieties might be more affected. In our plant date studies at Milan, early and late May planted Maturity Group 4 and 5 varieties had more seed disease at harvest than Group 2 or 3 beans planted during May; however, quality will depend on specific local growing conditions of the seed bean.
■ Apply a seed fungicide – fungicide can improve germination percentages of lesser-quality seed.
■ Don’t underplant to save seed — this is probably not the year to trim seeding rates with lower-germ seed, especially if planting into challenging conditions like cold or very hot soils or into cover crops.
Dr. Angela McClure is a University of Tennessee Extension corn and soybean specialist. She may be reached at firstname.lastname@example.org