Uptake of Antibiotics

The bacterium, Erwinia herbicola, produces both the antibiotics herbicolin and phenazine. Experiments in agricultural soil with wheat seed treated with the bacterium showed uptake of herbicolin in the roots and crown after four days of plant growth. This is believed to be the first report of colonization of plant roots and the uptake of an antibiotic in natural agricultural soil.

The credit goes to H. J. Kempf who investigated this phenomenon while employed at Ciba Geigy. A large company in Italy also was interested in bacteria that could be used as a bio-control.  This company had a number of field plots such as with beans where seeds were treated with antibiotic bacteria. House records showed a reduction of mildew on the leaves from treated seed.    M. N. Schroth who was a consultant verified this. Unfortunately, administrators of both companies dropped the programs believing it would not be commercially productive. This type of research was in its infancy in the late 1980’s, but it could be a very promising area in management of soil to support healthy plants.  Microorganisms, as with all living organisms, need food and water. The challenge is to develop techniques that preferentially support the beneficial microorganisms. Crop rotation is one way but is a non-specific method to alter the populations and kinds of microbes. Our research led us to adding various non toxic chemicals in drip systems in an attempt to stimulate certain bacteria and had some success.  Unfortunately, we ran out of support.

Kempf, HJ, Bauer PH, Schroth, MN. Herbicolin A-associated with crown and roots of wheat after seed treatment with Erwinia herbicola B247. Phytopathology 83:213-216. 1993.   

Kempf HJ, Sinterhauf S, Muller M, Pachlatko P. Production of two antibiotics by a biocontrol bacterium in the spermosphere of barley and in the rhizosphere of cotton, P 114-116. In Ryder MH, Stephens PM, Bowen, GD, editors. (Ed), Improving plant productivity with rhizosphere bacteria.  CSIRO Division of Soils, Adelaide, South Australia, Australia. 1994.