The science behind breeding, seeding and growing alfalfa explained
S&W Seed Company’s Alfalfa Breeder, David Mickelson shares the ins and outs of breeding alfalfa during the Bottom-Up Focus of Forage webinar series on Feb. 15.
Based in Wisconsin, S&W Seed Company was founded by two farmers during the 1980s with the vision to become the world’s preferred proprietary seed company. The company is involved in alfalfa breeding, sorghum, sunflower breeding and the natural sweetener, Stevia.
Mickelson became an alfalfa breeder for S&W Seed Co. during the 90s. Over time he has witnessed alfalfa breeding become more diverse and regulated with technologies to include Near-infrared spectroscopy (NIRS).
Alfalfa genetics
“Alfalfa genetics are more complicated than other crops,” Mickelson says. “They aren’t like corn where there are true hybrids, but they also aren’t like wheat or soybeans where the plants self-pollinate.”
Mickelson shares every seed in a bag of alfalfa seeds are genetically similar. However, alfalfa varieties are characterized by percentages of genes, meaning every seed in the bag is also genetically different in some way.
The main goal of alfalfa breeders is to breed better alfalfa. For this to happen, many improvements including higher yield, disease resistance, insect resistance, nutrient density and palatability can be made.
Disease and insect resistance can be tested in the greenhouse, according to Mickelson. However, to see how the yield quality has improved, researchers have to monitor plants in the field for several years. It can take up to eight years for certified seed companies to sell to farmers.
Alfalfa breeding procedures
There are several different breeding processes when breeding alfalfa. Mickelson shares phenotypic recurrent selection and genotypic selection are the most popular processes.
Phenotypic recurrent selection is the simplest method in terms of alfalfa breeding.
“Researchers use between 80 and 200 different parent plants,” he explains. “This method is used to shift the population to get a specific trait without losing the good qualities plants already have.”
As plants grow, researchers will essentially try to kill all the disease and insect susceptible plants, according to Mickelson. Researchers plant the strongest, hardiest plants in the nursery to be evaluated for several different things based on how the plant looks.
“Genotypic selection is considered parent-progeny testing,” says Mickelson. “Researchers only use between four and 30 different parent plants from synthetic varieties of alfalfa.”
Using a smaller amount of plants allows researchers to have better knowledge of the genetics of the parent plants.
Alfalfa breeding is a reoccurring cycle, Mickelson notes. Researchers consistently select superior plants, make breeding decisions, inoculate to test seeds for disease and insect resistance, screen for yield quality and eventually mass-produce the seeds.
Planting an alfalfa field
The best improvements to alfalfa seeds can be made through breeding decisions, but field care and planting practices greatly impact the ability of seeds to grow successfully.
“Checking the pH levels of a field is an important task,” Mickelson says. “Before seeding, farmers should ensure a good seed bed and proper pH levels in their fields.”
He adds it is always a good idea to have soil tested or enroll the help of an Extension agent if alfalfa fields are not seeing success.
He recommends farmers prepare their fields correctly to optimize the amount of alfalfa harvested. Mickelson adds it is a good idea for producers to purchase newer alfalfa strains because most are coated with a fungicide.
“Alfalfa varieties are extremely hard to identify in the field, so farmers can’t really identify what they have planted before unless it is in their records,” Mickelson states. “I recommend farmers look at newer alfalfa seeds because there are continual improvements.”
Madi Slaymaker is the editor of the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.
