Seed Endophytes

Abstract

Endophytes are those bacteria and fungi that exist within the tissues of plants without negative effects on host plants. They have been reported from all the plants exam- ined to date. Some endophytes are vectored on or within seeds of plants. These microbes are acquired by plant seeds and may be important to seedling development. Endophytic microbes support plants through mobilization of nutrients from soils, production of phytohormones, and further protecting plants from biotic (fungal pathogens and insects) and abiotic stresses. Further, seed microbes move into the plant body, protecting the plant from disease and improving the nutritional status of the entire plant. Endophytic bacteria stimulate the expression of host genes relating to nitrogen metabolism and hormone synthesis. The presence of endophytes also induces host defense genes in plants and makes them less susceptible to disease. Endophytic microbes produce a large number of agriculturally important metabolites. Seed-associated microbes are believed to be more adapted to plants and have ecological significance. Application of the seed microbiome in agriculture is needed at this time. We believe that seed and seedling microbes will ultimately replace the use of chemical fertilizers and pesticides that degrade the environment.