Properties of associative/endophytic bacteria for plant growth improvement. Based on the properties, associative/endophytic bacteria have been classified as Plant Growth Promoting Bacteria (PGPB) and biocontrol bacteria. PGPB may benefit associated plants through providing nutrition (nitrogen, phosphorous and iron), production of plant hormone and may enable plant tolerate abiotic stressors. Biocontrol bacteria (right panel in figure) protect plants from invasion of pathogenic microorganisms through antagonism and/or induced systemic resistance.