By Scout Nelson
Seed coatings are a crucial aspect of modern agriculture, particularly in the cultivation of forage legumes like alfalfa. These coatings, which can vary in their composition, are designed to enhance germination, seedling vigor, and seedling survival.
A common type, the 34% seed coating for alfalfa, includes essential components like Rhizobium and fungicides, crucial for nitrogen fixation and protection against seed and seedling diseases.
Craig Sheaffer, an Extension forage agronomist, outlines the dual role of these coatings: improving seed flowability and distribution while affecting the pure live seed (PLS) percentage in a seed bag.
Although these coatings, containing elements like mycorrhizae, growth promoters, and hydroscopic materials, can potentially lower the PLS, their benefits in reducing establishment risks are significant.
Using a theoretical model, Sheaffer compares the outcomes of different seed coating levels. For instance, a 34% coating on seeds with a 95% germination rate results in a lower PLS in the bag compared to a 10% coating. The trade-off comes in the form of enhanced seedling establishment and reduced failure risks, crucial for crops like alfalfa.
The Alfalfa Management Guide recommends seeding rates of 12-15 lb/acre for the Midwest. Research indicates that even with a 34% seed coating, the resulting seed density is sufficient for high yields, thanks to improved seedling survival rates.
Considering local environmental factors, soil conditions, and seeding technology when determining the appropriate seeding rate with coated seeds are important.
While seed coatings may reduce the PLS percentage, their role in enhancing germination and seedling survival in crops like alfalfa cannot be overstated. The future of alfalfa cultivation lies in leveraging these advancements for optimal yields and sustainable farming practices.
Photo Credit - gettyimages-goodlifestudio
Categories: Minnesota, Crops, Alfalfa