Coating of seeds with biological agents is known as

Coating seeds with biological agents is known as Bio priming.
Bio-priming is a coating process or seed treatment with beneficial PGPR under controlled hydration conditions, which improves the preparatory methods before germination without the emergence of the radicle.
Seed priming with living bacterial inoculum is termed biopriming that involves the application of plant growth-promoting rhizobacteria.
It improves harvest quality and yield of seeds.