HAZEN, Ark. – A three-year study of soybean seed quality by the University of Arkansas System Division of Agriculture has found accelerated aging to be a valuable aid in assessing the quality of seed when compared with standard germination testing, researchers said Tuesday.
Rick Cartwright, associate director of agriculture and natural resources, John Rupe, professor of plant pathology, and Kimberly Cochran, a Ph.D. student, presented their findings at a crop production meeting in Hazen last week. Though it was the last item on a daylong agenda, the presentations drew lively questions from the audience.
Researchers designed the study to understand the effects of storage on seed quality and the seed’s ability to emerge and establish a productive plant under field conditions. All seed is required to undergo a standard germination test and the results printed on the seed label. Under this test, seeds are placed on blotter paper and germinated during a week of ideal conditions. In the accelerated aging test, or AA, seeds are placed under stress for three days, and then germinated. Accelerated aging is an accepted method widely used, but not required by law.
Accelerated aging provides an estimate of seed vigor, a complex property that prompts the seed to “push out of the soil,” Cartwright said. “It’s a more complicated trait, but is valuable to understand for the high-value seed being planted today.”
Trends in the three-year planting seed survey indicated that more often than not, the lower the accelerated aging score, the worse the stand, while standard germ values did not run parallel with the stands in this study. “This indicates that seed vigor is very important, especially under less-than-ideal planting conditions such as in June, when it is getting hotter and drier.
“Vigor does not stay constant in soybean seed in the South,” he said. “It tends to decline in storage over time, especially for seed to be used in June or July in the state.”
The full story, including how the study worked and ramifications, is available at www.uaex.edu/news/january2012/0119ArkSoySeedStudy.html