Alfalfa Seed Coatings: An Economical Insurance Policy
Jeremy Hayward, WL Alfalfa Brand Manager
Understand the Technology
Seed treatments are not the same as seed coatings; understanding the distinction is important. An alfalfa seed treatment generally consists of an inoculant with a specific strain of rhizobium bacteria for alfalfa, along with a base fungicide to manage early-season soil diseases. Alfalfa seed inoculated with rhizobium bacteria helps ensure proper nodulation so the plant can fix nitrogen for its growth and development. In addition to rhizobium, a base fungicide like metalaxyl (Apron®) or mefenoxam (Apron XL®) in a standard seed treatment helps protect germinating seed from early-season fungal diseases, including phytophthora & pythium. Additional fungicides like pyroclostribin (Stamina®) can also be utilized for additional seedling disease control against Aphanomyces, Rhizoctonia, & Fusarium.
A seed coating provides more protection than a standard seed treatment. The seed coating, only consists of calcium carbonate and an inert polymer to keep nutrients and other active ingredients close to the seed to help prevent leaching during germination. Seed coatings may also add weight to small alfalfa seeds, helping improve plantability for more even emergence. A rhizobium inoculant and fungicide, along with additional specialized components like growth promoters, micronutrients, mycorrhizae, insecticides and bioenhancers could also be added to the coating as additional treatments. A seed coating may also include hydration polymers that draw moisture to the seed to aid in germination, even in shallow, dry soil.
Insurance for Uncertain Conditions
Weather often limits planting windows, and early-season pests can inhibit germination and plant establishment. The value of a seed coating and treatment helps to mitigate against these conditions at a small cost, relative to the price of the seed. This extra protection can mean the difference between a good crop and a great crop, because alfalfa that has a more vigorous start has a better chance to meet its yield potential.
Research done over the years shows a traditional seed coating can convert 50-75 percent of alfalfa seeds to healthy plants. When planting uncoated or lightly coated seeds, growers can expect 20-40 percent to germinate into healthy plants. Farmers will see the most benefit from a seed coating during the first 60 days after planting, when the stand is being established. Research has shown that the number of replanted alfalfa acres also declines when a seed coating is added.
W-L Alfalfas
W-L Research developed Gold Treatment® Plus seed coating and treatment. Gold Treatment® Plus is a premium seed enhancement for use on all W-L Brand Alfalfas. It includes the LCO promoter Optimize® Gold, which initiates the nodulation and nitrogen-fixing processes early, giving young alfalfa seedlings a boost and enhancing seeding-year populations, and thus yield and nutritional values. To double up on protecting young seedlings from mortality, W-L’s Gold Treatment® Plus also includes Stamina® fungicide to enhance broad-spectrum protection from seed and seedling diseases such as aphanomyces, phytophthora, & rhizoctonia. With in-plant resistance coupled with premium growth promoters and seed protection, W-L’s Gold Treatment® Plus is a leader in the industry in getting stands off to a strong start that will carry them for years to come.
Apron is a registered trademark of Ciba-Geigy. Apron XL is a registered trademark of a Syngenta Group Company. Stamina is a registered trademark of BASF.