Microbes and seeds

One of the reasons #biostimulants can be very effective when
placed on seeds is that the majority of microbes in the #rhizosphere
(the soil surrounding plant roots) originate from plant
seeds, rather than just from the soil itself.

Seeds contain hundreds of species of bacteria, archaea, fungi, and protists. When a seed
germinates, the microbes multiply and move into the new roots
and the soil surrounding the roots. The plant forms its own microbiome,
distinctly different from the microbiome of bulk soil.

The presence of microbial stimulants can enhance this process.
As the plant grows and develops, microbes that originated in
the seed continue to multiply and colonize the newly formed
stems, leaves, and flowers. Microbes are eventually incorporated
back into seeds in readiness for the next generation.

Completes the cycle.

As is the case for water-soluble N and/or P fertilizers, seed-applied
fungicides and insecticides disrupt the extremely important
communication that normally takes place between
germinating seeds and their microbes.

The most effective protection
against pests and diseases is a flourishing soil ecosystem
that supports symbionts such as mycorrhizal fungi and
a wide diversity of invertebrates including earthworms and
beneficial insects.