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Investigation of bacteriostatic & bacteriocidal properties of herb essential oils on the plant pathogenic bacteria - HH3209SX

The main objective is to determine the in vitro bacteriostatic and bacteriocidal properties of a range of herb essential oils on cultures of the major genera of plant pathogenic bacteria. Knowledge of the ability of herb oil to prevent the growth of bacterial plant pathogens would be of use to horticultural R&D workers.

The relevance to policy is to help meet the DEFRA aim to encourage the development of crops for industrial applications. Field grown herbs represent a potential growth market for UK agriculture. Herb extracts have been implicated as possible alternatives to synthetic antimicrobials. Before legislative and political issues are addressed, a good scientific basis for this claim must be established.

Herb oils represent a potential treatment for the control of bacterial plant pathogens. There are few effective or acceptable treatments available for these diseases. Use of herb oils could potentially lead to more effective and environmentally friendly disease control methods through the use of non-synthetic pesticides.

Our results could be of use for the development of crops for industrial use as antimicrobials.
To test the efficacy of the antibacterial properties of the herb essential oils. These will be tested against representatives of the major genera of bacterial plant pathogens. These include: Acidovorax, Agrobacterium, Brenneria, Burkholderia, Clavibacter, Curtobacterium, Enterobacter, Erwinia, Pantoea, Pectobacterium, Pseudomonas, Ralstonia, Rhodococcus, and Xanthomonas.
1) To identify herb essential oils to be used, by reviewing literature to establish if antimicrobial activity has been reported and wether the herb could readily be produced in the UK. No less than 5 oils will be tested.
2) To identify the most appropriate organisms to test as representatives of the above genera: to establish which diseases are likely to be best treated by application of herb oil and wether they pose a plant health risk to the UK. It is envisaged that no less than 10 species will be tested.
3) To test the methods chosen using a select panel of strains and herb essential oils; in order to establish which of the two identified methods are best at determining bacteriostasis/bacteriocidal properties. It is envisaged that the oil(s) with the highest degree of bacteriostasis identified in 1) from the current literature will be tested with the bacterial strain(s) most likely to be treatable with herb oil application as identified in 2). The efficacy of the herb oil will be tested using a dilution of the herb oil inoculated with a known concentration of bacteria (probably 107 colony forming units/ml).
4) To test each strain identified 2) against each herb essential oil identified in 1).
5) To present the results in the form of a short report.
Project Documents
• Final Report : Investigation of bacteriostatic & bacteriocidal properties of herb essential oils on the plant pathogenic bacteria   (217k)
Time-Scale and Cost
From: 2002

To: 2002

Cost: £6,965
Contractor / Funded Organisations
Central Science Laboratory
Antimicrobial Resistance              
Protected Cropping              
Fields of Study