​Development and assessment of specific probes for the detection and monitoring of toxin-producing phytoplankton species in Scottish waters

Summary

Scottish Association for Marine Science
Davidson, K

This project aimed to develop molecular-based techniques for the identification and listing of toxin producing phytoplankton species in Scottish waters, such as Alexandrium tamarense, Azadinium spinosum and other Azadinium species.

The project demonstrated that molecular methods are capable of detecting and enumerating group I and group III Alexandrium tamarense, and Azadinium spinosum in Scottish waters.

Fluorescence in situ hybridization (FISH) -based Alexandrium detection was found to be suitable for the couting of, and discrimination between, toxic and non-toxic groups of Alexandrium tamarense in Scottish waters.

Three methods of enumeration of the fluorescently labeled Alexandrium tamarense cells were evaluated. Of these, fluorescence microscopy was found to be more time/cost efficient than automated methods and allowed cross-reactivity with non-target cells to be assessed visually.

Given the operational difficulties of on-site sample screening and the costs of transporting relatively large volumes of water, with the possibility of some cell loss during transport, the Alexandrium FISH method is not recommended for routine use to characterise the Alexandrium community at all phytoplankton monitoring sites. Rather, it is recommended that the method should be used when possible allowing important developing blooms to be categorised as toxic and non-toxic groups when necessary.

Project Code: FS241058