Towards standardized molecular monitoring of HABs: A consensus guide to qPCR.

Source: PubMed, NCBI / U.S. National Library of Medicine

Harmful algal blooms (HABs) are a growing concern in marine and freshwater ecosystems due to their adverse impacts on human health, aquatic ecosystem functioning, and economic activities. Conventional HAB monitoring based on morphological identification remains important but is often limited by time, resolution, and reliance on expert taxonomists. Quantitative PCR (qPCR) and digital PCR (dPCR) techniques have emerged as powerful molecular tools for the specific, sensitive, high throughput and rapid detection of HAB species. This review, based on a consensus among experts in the field, aims to provide an accessible, practical guide for integrating qPCR and dPCR for current and future HAB monitoring frameworks. Building upon previously published literature reviews with a broader focus, we present the details and specifics of step-by-step approaches of assay design, validation, application in global and regional monitoring programmes, and recommendations for method standardization and future development. This consensus guide provides valuable information to benefit laboratory users, regulatory and monitoring agencies. Detailed information is provided for ∼175 qPCR assays directed at >70 marine and freshwater HAB taxa. Our goal is to bridge the gap between research and operational monitoring, provide a unique, shared perspective of the use of quantitative species-specific molecular methods across applications and world regions.