Photosynthetic responses of Pyropia yezoensis f. narawaensis (Bangiales, Rhodophyta) to a thermal and PAR gradient vary with the life-history stage

Non‐Random Distribution and Ecophysiological Differentiation of Pyropia Species (Bangiales, Rhodophyta) Through Environmental Gradients

“…This is the case with species belonging to the Porphyra/Pyropia complex due to alternations in the gametophyte (macroscopic, haploid phase) and sporophyte (microscopic, diploid phase) phases (conchocelis). Furthermore, different optimal temperatures and PAR values have been determined for Pyropia yezoensis and Pyropia tenera for the gametophyte and sporophyte phases (Watanabe et al 2014(Watanabe et al , 2016, with seasonal variations existing between gametophytes (winter-spring) and sporophytes (summer; Watanabe et al 2014). Considering this, we suggest that P. orbicularis and P. variabilis (LM and GM) may possess different physiological responses in both life stages; where P. orbicularis gametophytes occurring in the summer would have greater environmental tolerances due to being faced with higher temperatures, reproducing in the early winter when environmental pressures are lower.…”

“…Furthermore, different optimal temperatures and PAR values have been determined for Pyropia yezoensis and Pyropia tenera for the gametophyte and sporophyte phases (Watanabe et al. , ), with seasonal variations existing between gametophytes (winter‐spring) and sporophytes (summer; Watanabe et al. ).…”

Chronological change and the potential of recovery on the photosynthetic efficiency of Pyropia yezoensis f. narawaensis (Bangiales) during the sporelings frozen storage treatment in the Japanese Nori cultivation

“…Japanese Nori cultivation uses a ‘full‐cycle farming’ approach that does not rely on wild species, and a few cultivars have been selected for cultivation. In particular, Pyropia yezoensis (Ueda) Hwang et Choi f. narawaensis Kikuchi, Niwa et Nakada is the primary cultivar, and is cultivated throughout Japan (Miura ; Kawamura et al ; Oohbusa ; Watanabe et al ).…”

“…Our recent studies have revealed the clear response of photosynthesis along a gradient of temperature and PAR for a number of commercially important algae using the pulse amplitude modulated (PAM) fluorometer (Watanabe et al , ,, ). We have previously noted that, assessing maximum and effective quantum yields ( F v / F m and Φ PSII ) of photosystem II under a variety of environmental conditions are a quick and valuable indicator of photosynthetic response (Fujimoto et al , ; Kokubu et al ; Terada et al ).…”

“…We have previously noted that, assessing maximum and effective quantum yields ( F v / F m and Φ PSII ) of photosystem II under a variety of environmental conditions are a quick and valuable indicator of photosynthetic response (Fujimoto et al , ; Kokubu et al ; Terada et al ). Indeed, our recent study of Pyropia tenera (Kjellman) Kikuchi, Miyata, Hwang et Choi demonstrated that the optimum temperature ranges for F v / F m of the macroscopic gametophyte and microscopic sporophyte differed, and were most likely related to the temperatures occurring in their habitat (Watanabe et al , ).…”