This study was carried out to work towards a better understanding of the interactions between ticks and <i>Metarhizium anisopliae, </i>an entomopathogenic fungus with the potential of being developed into a fungal biocontrol agent for this important pest of livestock and humans, and to perform preparatory work for field trials to be carried out by the group in the near future. A rapid and simple method of isolating and characterising <i>M. anisopliae</i> from soil samples has been developed, incorporating a spore floatation method of isolation, DNA extraction using FTAÒ cards and three PCR-RFLP methods of molecular characterisation, two of which have not yet been successfully applied in this area. During the development of the methods, a database of local <i>M. anisopliae </i>strains was constructed, all of which will collectively be essential for tracking and evaluating released strains. None of these local strains showed promise as potential tick biological control agents, but bioassays identified two tick-pathogenic strains that could be developed into biological control agents. The virulence of these and two other strains was found to differ greatly towards insect and tick species. Microscopy and biochemical studies have found that there are differences in spore attachment and germination on insect and tick cuticle that may influence virulence. Great variation was also seen in the properties of Pr1 enzymes produced by the four test strains of <i>M. anisopliae.</i> Although this may be expected to play an important role in virulence, results did not corroborate with those obtained in bioassays, revealing an area requiring further investigation.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:638654 |
| Date | January 2006 |
| Creators | Rice, N. V. P. |
| Publisher | Swansea University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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