Blue and green light‐induced release of swarmers in Petalonia fascia (Ectocarpales, Phaeophyceae)
Year: 2025
Type: article
Abstract: SUMMARY Understanding the environmental factors that influence the release of eggs and swarmers, including gametes, zoospores and unsexual swimming cells, is essential for deciphering the survival strategies of brown algae. In the present study, we investigated the mechanisms underlying the light‐induced release of swarmers in Petalonia fascia. We found that swarmer release was triggered by light, especially blue and green light, with red light having a significantly smaller effect. Swarmer release was not directly affected by photosynthesis. In addition, the duration of light exposure was crucial: even when the total number of photons was low, a longer exposure time resulted in a higher release rate of swarmers. This result suggests that a minimum light exposure time is necessary for swarmer release. We also investigated the influence of a circadian rhythm on swarmer release. Under continuous light conditions, swarmers were released at subjective dawn, thus indicating a circadian rhythm influence. By contrast, no release occurred at subjective dawn in continuous darkness. This result suggests that light is necessary to trigger release, even when circadian rhythms are involved. Our findings, which demonstrate that light quality, exposure time and circadian regulation are critical factors for swarmer release in P. fascia, provide new insights into how environmental cues influence reproductive processes in brown algae.
Source: Phycological Research
DOI: 10.1111/pre.12580
Authors: Tsunami Hiyama, Shiya Yoshikawa
Institution: Fukui Prefectural University
Language: English
Subfield: Oceanography
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Life below water
Open Access status: bronze
OpenAlex ID: W4407262458