Plant Growth–Promoting Bacteria Facilitate the Growth of the Common Reed Phragmites australisin the Presence of Copper or Polycyclic Aromatic Hydrocarbons

Abstract

To test whether plant growth-promoting bacteria might be useful in facilitating the growth of Phragmites australis, the common reed, in the presence of metals and organic compounds, P. australis seeds were treated with plant growth-promoting bacteria. The bacterium Pseudomonas asplenii AC was genetically transformed to express a bacterial gene encoding the enzyme 1-aminocyclopropane-1-carboxylate deaminase, and both the native and transformed bacteria were tested in conjunction with P. australis. Inoculation of seeds, which were subsequently grown in the presence of copper or creosote, with transformed P. asplenii AC significantly increased seed germination. Moreover, the addition of either native or transformed P. asplenii AC to P. australis seeds enabled the plants (shoots and roots) to attain a greater size than noninoculated plants after growth in soil in the presence of either copper or creosote.