Chlorophyll fluorescence-A tool to assess photosynthetic performance and stress photophysiology in symbiotic marine invertebrates and seaplants

Chlorophyll a fluorescence is increasingly being used as a rapid, non-invasive, sensitive and convenient indicator of photosynthetic performance in marine autotrophs. This review presents the methodology, applications and limitations of chlorophyll fluorescence in marine studies. The various chlorophyll fluorescence tools such as Pulse-Amplitude-Modulated (PAM) and Fast Repetition Rate (FRR) fluorometry used in marine scientific studies are discussed. Various commonly employed chlorophyll fluorescence parameters are elaborated. The application of chlorophyll fluorescence in measuring natural variations, stress, stress tolerance and acclimation/adaptation to changing environment in primary producers such as microalgae, macroalgae, seagrasses and mangroves, and marine symbiotic invertebrates, namely symbiotic sponges, hard corals and sea anemones, kleptoplastic sea slugs and giant clams is critically assessed. Stressors include environmental, biological, physical and chemical ones. The strengths, limitations and future perspectives of the use of chlorophyll fluorescence technique as an assessment tool in symbiotic marine organisms and seaplants are discussed.

Automated summary

Chlorophyll a fluorescence is a valuable tool for assessing photosynthetic performance in marine autotrophs, providing rapid, non-invasive, sensitive and convenient measurements. This technique, including tools like Pulse-Amplitude-Modulated (PAM) and Fast Repetition Rate (FRR) fluorometry, is widely used in marine studies to measure natural variations, stress responses, and adaptation to changing environments. Stressors can include environmental, biological, physical, and chemical factors, and the strengths, limitations, and future perspectives of using chlorophyll fluorescence in assessing symbiotic marine organisms and seaplants are carefully evaluated.