Colonization by endophytic Ochrobactrum anthropiMn1 promotes growth of jerusalem artichoke

Abstract

The Ochrobactrum anthropiMn1 strain, taxonomically identified using 16S ribosomal DNA sequence, was isolated from roots of Jerusalem artichoke. Its endophytic colonization was investigated microscopically using green fluorescent protein introduced by vector pHC60. The strain entered Jerusalem artichoke tissues through the root, and was localized in the roots and stems. The plant growth-promoting (PGP) effects of O. anthropiMn1 were assessed in greenhouse as well as field trials with different nitrogen supplies. Only under moderate to ample nitrogen supply, could O. anthropiMn1 promoted growth of host plant. The PGP effects of the strain were symbiotic nitrogen fixation, root morphological optimization and enhanced nutrient uptake. We hypothesize that the symbiotic interspecies interaction might be quorum sensing related.