THE EFFECT OF LONG-TERM CD AND NI EXPOSURE ON SEED ENDOPHYTES OF AGROSTIS CAPILLARIS AND THEIR POTENTIAL APPLICATION IN PHYTOREMEDIATION OF METAL-CONTAMINATED SOILS

• Published in: International Journal of Phytoremediation
• Main Authors: Truyens, Sascha, Jambon, Inge, Croes, Sarah, Janssen, Jolien, Weyens, Nele, Mench, Michel, Carleer, Robert, Cuypers, Ann, Vangronsveld, Jaco
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2014
• Subjects: agrostis capillaris; metals; seed endophytes; phenotypic characterisation; plant growth promotion; Greenland
• Online Access: http://hdl.handle.net/1942/16371; https://doi.org/10.1080/15226514.2013.837027

We examined whether long-term Cd exposure leads to beneficial changes in the cultivable endophytic bacteria present in the seeds of Agrostis capillaris. Therefore the cultivable seed endophytes of Agrostis capillaris growing on a long-term Cd/Ni-contaminated plot (Cd/Ni seeds) were compared with those originating from a non-contaminated plot (control seeds). We observed plant- and contaminant-dependent effects on the population composition between control and Cd/Ni seeds. Also differences in phenotypic characteristics were found: endophytes from Cd/Ni seeds exhibited more ACC deaminase activity and production of siderophores and IAA, while endophytes from control seeds, very surprisingly, showed more metal tolerance. Finally, the 3 most promising seed endophytes were selected based on their metal tolerance and plant growth promoting potential, and inoculated in Agrostis capillaris seedlings. In case of non-exposed plants, inoculation resulted in a significantly improved plant growth; after inoculation of Cd-exposed plants an increased Cd uptake was achieved without affecting plant growth. This indicates that inoculation of Agrostis with its seed endophytes might be beneficial for its establishment during phytoextraction and phytostabilisation of Cd-contaminated soils. This research was funded by the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen) for J.J. and by the Fund for Scientific Research Flanders (FWO-Vlaanderen), Ph.D. grant for S. C. and S. T. and post-doc grant for N.W. This work has been financially supported by the UHasselt Methusalem project 08M03VGRJ and by the European Commission under the Seventh Framework Programme for Research (FP7-KBBE-266124, GREENLAND).