2019 ASHS Annual Conference

The benefits of cover cropping in both organic and conventional managed systems include improving soil organic matter, soil structure and nutrient cycling, and reducing soil erosion. Red clover, Trifolium pratenseis widely used as a forage and also as a cover crop in the Northeast, US. Interseeding cover crops may be sown several weeks or months after the main crop is planted. Seed coating technologies incorporating nutritional materials and biostimulants may enhance germination and seedling growth. The current study aimed to develop novel seed coatings formulation using biostimulant components to accelerate the germination of seeds, increase the germination rate and uniformity and enhance early seeding establishment. Red clover seeds were coated with different combinations of soy flour that served as a biostimulant and binder, with diatomaceous earth, micronized vermicompost, and concentrated vermicompost extractapplied as a seed coating blend. Coating experiments were conducted by increasing the proportion of soy flour in the blend from 30-60% by weight. Allcoatings were applied with rotary pan seed coater with 30% build-up by the seed weight. The surface mechanical properties of coated seeds are important indexes to evaluate the quality of coated seeds. The first method used a mechanical shaker (Ro-Tap) to test the integrity of coated seeds. The second method used a texture analyzer (TA.TX-Plus) to measure compressive strength of coated seeds. The third method was a hydration test by soaking coated seeds till they disintegrated. Increasing the proportion of soy flour in the coating blend increased the integrity and compressive strength of coatings, and the time for coatings to disintegrate. The seed coating treatments and non-coated seeds were planted in roll towels in a germinator at 20° C with a photoperiod of 16/8 hours. The results show that coated treatments had a significantly improved germination rate and uniformity with no reduction in total germination compared to the nontreated control. Shoot length, seedling uniformity, seedling vigor index, and dry weight of seedlings of all coated seed treatments were also significantly higher compare to control. Coating technology can be an effective strategy to maximize early stand establishment of cover crops. Keywords: Red clover, Seed treatment, Cover crops, Interseeding