Induction and isolation of pigmentation mutants of Porphyra yezoensis (Bangiales, Rhodophyta) by heavy‐ion beam irradiation

Abstract

The present study describes the isolation of pigmentation mutants of Porphyra yezoensis Ueda induced by heavy-ion beam irradiation for the first time. The gametophytic blades were irradiated with 12 C +6 ion beams within a dose range of 25-400 Gy. From the survival rate and cell growth of the irradiated blades, it is suggested that a dose of 150 Gy or less is suitable to induce mutation for the isolation of mutants of P. yezoensis. After irradiation, red, green and deep reddish brown-colored gametophytic blades developed from archeospores that were released from each of the mutated cell clusters of the respective different colors, and the red mutant strain (IBY-R1) and green mutant strain (IBY-G1) were established as a conchocelis colony in culture. Blades of the mutants were characterized by their growth and photosynthetic pigment contents compared with those of the wild-type. From these results, it is clear that heavy-ion beam mutagenesis will be an effective tool for genetic and breeding studies of Porphyra, and also for other algal research.

Phycobilisome composition in Chondrus crispus (Gigartinales, Rhodophyta) from a wild type strain and its vegetatively derived green mutant

“…Colour mutants have also provided important model systems for studying mechanisms of inheritance in red algae in a variety of genera including Chondrus (e.g., van der Meer 1981) and Gracilaria (Plastino et al 1999, 2004, Costa and Plastino 2011. Some of these mutants may be artificially produced by various chemical (e.g., Yan et al 2000) or radiation treatments (e.g., Niwa et al 2009), or spontaneously occur in culture (e.g., Chondrus) (van der Meer 1981, Staples et al 1995 such as the Chondrus used in this study. While green mutants may be common in nature, with frequencies of up to 19% recorded for a Gracilaria from Brazil (Guimaraes et al 2003), green mutant strains of Chondrus (Staples et al 1995) and Hypnea (Yokoya et al 2007) generally do not perform as well as wild-type strains in culture.…”

ASSESSMENT OF PHOTOSYNTHETIC PERFORMANCE OF PORPHYRA YEZOENSIS (BANGIALES, RHODOPHYTA) IN CONCHOCELIS PHASE1

“…2008). The target strains have been characterized in terms of in vivo absorption spectra, photosynthetic pigment contents of the blades in comparison with wildtypes (Niwa et al. 2009), and in terms of their physiological photosynthetic traits in different conditions and growth rates and lengths of mature blades (Marquardt et al.…”

Study on the photosynthetic characteristics of a Pyropia haitanensis red mutant cultured under different light intensities

“…With the development of related technology, mutagenesis, genetic recombination, and other methods have been applied in Pyropia breeding. Different mutants, including pigment mutants, have been induced through chemical mutagens (Mitman and van der Meer 1994;Zhu et al 1998;, heavy-ion beams (Niwa et al 2009(Niwa et al , 2011, and γ-rays (Yan et al 2005). Pigment mutants of Pyropia are not only a good material for research on theoretical genetical problems but also have high application value; in fact, a previous study already indicated that a P. yezoensis red mutant showed superior characteristics in pigment and in free amino acid contents (Niwa et al 2011).…”

“…The breeding of cultivars with high yields, higher tolerances to disease or to environmental stresses, and better flavor of the dried products has attracted much attention from Pyropia researchers (Niwa et al 2009). In China, the annual production of P. haitanensis is much higher than that of Pyropia yezoensis (Bureau of Fisheries, State Department of Agriculture 2001Agriculture -2008; however, unlike P. yezoensis, the thickness of P. haitanensis makes this species difficult to process.…”