NCDA&CS seed lab testing for germination and purity
This is a busy time of year for farmers, when they have their attention on the field, finalizing plans for what crops to grow, determining how much seed to buy and tuning up equipment to make sure everything is field-ready.
It is also the time of year when the N.C. Department of Agriculture and Consumer Services’ seed lab is busy testing germination rates and purity on a variety of seeds including soybeans, wheat, oats, peanuts and vegetables. This is a service to seed producers in the state as well as the farmers who buy seed, said Danny Turner, Seed and Fertilizer Section manager. The lab also tests grass seed, which is a benefit to homeowners.
“What we do is all about the quality of the products and truth in labeling,” Turner said. “What it says on the bag, is what is supposed to be in the bag.”
A number of seed producers in the state grow crops specifically for seed. Turner estimates 75 to 80 percent of soybean and small grain seeds are grown within the state. Some of these businesses also buy and process from other seed growers. These crops earn a higher price, so a lot of extra work goes into them, coupled with a lot of expectation that they will produce good plants.
“When it comes to seed production, these companies have employees whose job it is to scout the fields and make sure the crop is as healthy as it can be. They scout it for disease and weeds and it has to be kept separate from any other seed varieties,” Turner said. “When you sell it for seed, it is a premium. They will clean it, will keep the moisture down in the seeds, and will store it in a controlled environment.”
High-quality seed is important to a successful growing season, and the work of the seed lab helps farmers know they are getting what they pay for.
Unlike a backyard gardener who may pick up a pack or two of vegetable seeds for $2 to $3 each, farmers are buying bulk quantities of seed and the cost can add up quickly.
“Cotton seed, particularly that with weed- and disease-resistant technology, can run nearly $500 a bag, corn seed from $250-$300 a bag and soybeans around $45 a bag,” Turner said. “They are not cheap commodities. If we don’t test it, a farmer is left wondering if he is getting what he paid for. The label is all he’s got to go on. You can’t tell whether seed will germinate or not just by looking at it with the naked eye. And seed that doesn’t germinate is wasted money.”
Seed samples are submitted by producers or collected by field inspectors. Most of the farm supply stores get their seed in by bulk, ranging from 50-pound bags to 2,000-pound boxes. Inspectors check labeling on the seed as well as for the nine-month test statement. Seed not meeting the stated germination rates or purity will be pulled from sale. There are around 4,500 seed retailers in the state.
By law, most agricultural seed that germinates below 70 percent cannot be sold as seed, Turner said. “You want so many plants per acre, so if seed has a low germination rate, it would take more to get the plant population to the level a farmer would want for a field,” he added.
The seed lab underwent a major renovation in 2011, but the work for its 13 employees has remained largely the same, with workers carefully preparing samples in wet paper towels and reviewing the sprouts that emerge from the seed to see if the seeds are viable.
Germination rates vary by seed type, so testing can take days or weeks to complete.
Given the wide variety of seeds that can come into the lab, each seed analyst undergoes extensive training on recognition of types of seeds, how to prepare seeds for testing, what to look for in terms of proper germination and how to identify weed seeds and other foreign materials in packages of seeds.
To earn national certification accreditation, analysts have to take a test. “Analysts have to know 250 different weeds seeds because they don’t know which seeds they will get on their tests,” Turner said. “Overall, seed analysts go through a rigorous process involving two to three years of training.”
Some of the seeds the analysts are working with are so small that the work must be done under a microscope. More and more coated seed are coming into the lab, Turner said, with some varieties already pretreated with fungicide or insecticides. For the lab to process these seeds, all the coating has to be scraped off and removed.
“I feel like what we do is an important service,” Turner said. “Whether you are a backyard gardener or a farmer planting a thousand acres, it is a good tool to ensure you are getting what you pay for.”
