Seasonal dynamics of harmful algae in outer Oslofjorden monitored by microarray, qPCR, and microscopy

• Published in: Environmental science and pollution research international 2013-10, Vol.20 (10), p.6719-6732
• Main Authors: Dittami, Simon M., Hostyeva, Vladyslava, Egge, Elianne Sirnæs, Kegel, Jessica U., Eikrem, Wenche, Edvardsen, Bente
• Format: Article
• Language: English
• Subjects: Algae; Algal blooms; Aquatic Pollution; Arrays; Atmospheric Protection/Air Quality Control/Air Pollution; Chlorophyll; Diatoms - classification; Diatoms - genetics; Dinoflagellida - genetics; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental monitoring; Environmental Monitoring - methods; Eutrophication; Extraction; Fisheries; Harmful Algal Bloom; Light microscopy; Marine pollution; Microalgae - classification; Microalgae - genetics; Microorganisms; Microscopy; Molecular tools for monitoring Harmful Algal Blooms; Monitoring; Norway; Oligonucleotide Array Sequence Analysis - methods; Phytoplankton; Phytoplankton - classification; Phytoplankton - genetics; Plankton; Public health; Real-Time Polymerase Chain Reaction; Sampling; Seasons; Studies; Time series; Toxicity; Waste Water Technology; Water Management; Water Pollution - statistics & numerical data; Water Pollution Control; Water quality
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-012-1392-0

Monitoring of marine microalgae is important to predict and manage harmful algal blooms. Microarray Detection of Toxic ALgae (MIDTAL) is an FP7-funded EU project aiming to establish a multi-species microarray as a tool to aid monitoring agencies. We tested the suitability of different prototype versions of the MIDTAL microarray for the monthly monitoring of a sampling station in outer Oslofjorden during a 1-year period. Microarray data from two different versions of the MIDTAL chip were compared to results from cell counts (several species) and quantitative real-time PCR (qPCR; only Pseudochattonella spp.). While results from generation 2.5 microarrays exhibited a high number of false positive signals, generation 3.3 microarray data generally correlated with microscopy and qPCR data, with three important limitations: (1) Pseudo-nitzschia cells were not reliably detected, possibly because cells were not sufficiently retained during filtration or lysed during the extraction, and because of low sensitivity of the probes; (2) in the case of samples with high concentrations of non-target species, the sensitivity of the arrays was decreased; (3) one occurrence of Alexandrium pseudogonyaulax was not detected due to a 1-bp mismatch with the genus probe represented on the microarray. In spite of these shortcomings our data demonstrate the overall progress made and the potential of the MIDTAL array. The case of Pseudochattonella — where two morphologically similar species impossible to separate by light microscopy were distinguished — in particular, underlines the added value of molecular methods such as microarrays in routine phytoplankton monitoring.