Porphyra drewiana, a new species of red algae (Bangiales, Rhodophyta) from Brazil

Porphyra drewiana Coll et Oliveira, sp. nov., is described from plants collected on the south‐east coast of Brazil. The species proposed is monostromatic, monoecious, monoplastidial, without marginal microscopic teeth and does not produce monospores. Both phases, leafy and filamentous, have three chromosomes. Morphologically the most similar species is Porphyra spiralis Oliveira et Coll var. amplifolia Oliveira et Coll, from which it differs by: (i) thallus gross morphology; (ii) scattered pluristromatic areas of vegetative cells; (iii) division of the plastids prior to the nucleus at the first division of the carpospores mother cell; (iv) the number of carpospores and spermatia produced per mother cell; and (v) morphology and behavior of the filamentous phase in cultures. An identification key for the species referred to Brazil is included.     

Life history in culture of the obligate epiphyte Porphyra subtumens (Bangiales, Rhodophyta) endemic to New Zealand

This is the first report of the growth in culture of Porphyra subtumens J. Agardh ex Laing (Bangiales, Rhodophyta), an obligate epiphyte of Durvillaea species and endemic to New Zealand waters. Archeospores, previously observed on field material, develop directly into the blade phase. Spores released from field collected blades form conchocelis. Conchospores develop into new blades, completing the life history in culture. Earlier reports of reproduction in P. subtumens gave conflicting accounts with some authors citing this species as having an asexual, monophasic life history with an unusual form of spore production, while others described spermatangia and carposporangia on the blade phase.     

Protoplast isolation and fusion in Porphyra (Bangiales,Rhodophyta)

Two sediment sampling campaigns were conducted in 1978 and 1988 in Lake Geneva (Switzerland). Organic carbon, total nitrogen, total phosphorus and its various forms were analyzed. Results indicate a stability of organic carbon and nitrogen mass, and a significant increase of phosphorus. The variation of phosphorus mass is related to the increase of nonapatite inorganic phosphorus. This study attempts to quantify the phosphorus exchanges at the water sediment interface. The dissolved oxygen level in the bottom water determines the exchange direction. In aerobic conditions, sediments accumulate the excess of phosphorus, while in anaerobic conditions, they constitute an internal source.     

Research Note: Simple molecular discrimination of cultivated Porphyra species (Porphyra yezoensis and Porphyra tenera) and related wild species (Bangiales,Rhodophyta)

To discriminate between cultivated Porphyra species (Porphyra yezoensis and Porphyra tenera) and closely related wild Porphyra species, we developed a polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) analysis of the rbcL gene using five restriction enzymes. Although our previous PCR‐RFLP analyses of internal transcribed spacer (ITS) rDNA and plastid RuBisCO spacer regions could not always discriminate wild P. yezoensis, wild P. tenera, and closely related wild species, the PCR‐RFLP profiles of the rbcL gene were useful in discriminating samples collected from natural habitats. Therefore, PCR‐RFLP analysis of the rbcL gene will help in the simple identification of a large number of samples, not only for the establishment of reliable cultures as breeding material, but also for the taxonomic investigations of species that are closely related to cultivated Porphyra.     

Phylogeny of the Bangia flora of New Zealand suggests a southern origin for Porphyra and Bangia (Bangiales, Rhodophyta)

Analysis of nuclear small subunit ribosomal RNA gene (18S rDNA) sequence data from 123 samples of the red algal genus Bangia from mainland New Zealand has revealed diversity exceeding that reported for the genus from any other region in the world. Our study resolves two New Zealand Bangia taxa basal to the order Bangiales, and five clades of Bangia, four of which include New Zealand members. The basal taxa are separated from each other by 139 bp and differ from all other Bangia taxa in the New Zealand region by 103-163 bp over approximately 1750 bp 18S rDNA sequence data. Our results reveal a Bangia flora of previously unsuspected richness, and show that the simple morphology of these organisms obscures significant levels of genetic diversity. The presence of high diversity and retention of basal taxa in New Zealand Bangia raises the prospect that the southern hemisphere, and particularly eastern Gondwana, is not only a centre of diversity, but a centre of origin for the modern Bangiales.     

An evaluation of species relationships in the Porphyra perforata complex (Bangiales,Rhodophyta) using starch gel electrophoresis

Traditional morphological features have formed the basis for distinguishing species of Porphyra. Among these features are number of cell layers, number of chloroplasts per cell, arrangement of reproductive structures on the thallus, and overall morphology. Chromosome number and chromosome morphology have helped corroborate some species identities. A survey of northeast Pacific species of Porphyra using starch gel electrophoresis of 15 soluble proteins has shown that electrophoretic banding patterns provide a reliable diagnostic tool for species identification. Data from starch gel electrophoresis are presented to confirm the identities of species formerly associated with the Porphyra perforata species-complex in British Columbia and northern Washington. Porphyra abbottae, P. fallax, P. kanakaensis, and P. torta are recognized as distinct species, and Porphyra sanjuanensis is synonymized with P. perforata.     

Use of PCR-RFLP for the discrimination of Japanese Porphyra and Pyropia species (Bangiales, Rhodophyta)

In order to distinguish 18 Porphyra and Pyropia species, the present study employed polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis using mitochondrial DNA related to the ATP synthase F0 subunit 6 (ATP6) gene and partial mitochondrial DNA including trnC, rps11, sdh3, trnG, trnN, trnP, and rns. The two primer sets on the mitochondrial DNA used in this study were able to amplify single fragments with PCR in 16 Japanese and 2 non-Japanese Porphyra and Pyropia species. Lengths of partial mitochondrial DNA related to ATP6 gene and trnC–rns ranged from 664 bp (Py. dentata and Py. haitanensis) to 677 bp (Py. lacerata and Py. kurogii) and from 1,292 bp (Py. seriata) to 1,343 bp (Py. kurogii and Py. moriensis), respectively. All 18 species were successfully distinguished using a combination of five restriction enzymes (TaqI, SspI, AciI, Cfr13I, and AluI). It was therefore concluded that PCR-RFLP analysis is a valuable tool for discrimination of wild strains of Porphyra and Pyropia species for potential use in mariculture.     

Rapid extraction of high-quality genomic DNA from Porphyra yezoensis (Bangiales, Rhodophyta)

We developed a simple, rapid and stable method for extraction of high molecular weight DNA from the marine red alga Porphyra yezoensis Ueda using both guanidium treatment and QIAGEN? kit (Funakoshi, Tokyo, Japan). The method does not require expensive equipment and complex steps. The DNA yield averaged 1.5 μg 100 mg^?1 of Porphyra tissue and the A260/A280 and A230/A260 ratios of the DNA were approximately 1.8 and 0.4, respectively. It was of sufficient quality to be used for not only polymerase chain reactions but also other DNA manipulation techniques such as restriction digestion and construction of genomic libraries.     

Conchospore production and seasonal occurrence of some Porphyra species (Bangiales,Rhodophyta) in Washington State

The leafy thalli of species of the marine red algal genus Porphyra grow rapidly but persist for a relatively short time on rocky intertidal or subtidal substrata or as epiphytes on other marine plants. In most species, the large, short-lived leafy thalli alternate with small, presumably perennial, filamentous conchocelis plants. Depending on the species of northeastern Pacific Porphyra, photoperiod and temperature are important regulators of conchospore formation and release. Data from laboratory studies of conchospore formation and release in five Washington species of Porphyra (P. abottae, P. nereocystis, P. perforata, P. pseudolanceolata and P. torta) indicate that conchospores are most likely to be released at a time that precedes the appearance of the leafy thalli in the field.     

Rapid DNA extraction from conchocelis and ITS-1 rDNA sequences of seven strains of cultivated Porphyra yezoensis (Bangiales, Rhodophyta)

In order to extract DNA rapidly from cultivated Porphyra, we extracted total DNA from conchocelis using the ISOPLANT II kit (Nippon Gene) without liquid nitrogen treatment or CsCl-gradient ultracentrifugation. By confirming the reproducibility of RAPD patterns, it is concluded that the quality of the extracted DNA is sufficient to use as a template for molecular investigation. Using this rapid method, the nuclear ribosomal DNA of the internal transcribed spacer (ITS) regions was amplified from seven strains of cultivated Porphyra, which had been maintained as free-living conchocelis by subculturing in the laboratory. From the amplified DNAs, the ITS-1 sequences were determined in order to identify the species and genetic relationship of the strains. The sequences were identical in the seven strains, and all the strains were identified as P. yezoensis. Furthermore, the gametophytic blades of these strains showed long linear or oblanceolate shapes in the laboratory culture. It was concluded that these strains are P. yezoensis form. narawaensis. This rapid DNA extraction method from conchocelis will be a powerful tool for phylogenetic analysis and for genetic improvement of cultivated Porphyra.     

ThePorphyra species of Helgoland (Bangiales,Rhodophyta)

This revision of sevenPorphyra species of Helgoland was based on a study of the structure of their fertile thalli and the behaviour of their spores. Regarding the reproductive organization the species may be arranged in two groups.P. leucosticta andP. purpureo-violacea are obligate monoecious species. Asexual thalli have never been observed in the field. The other five species are generally dioecious. Isomorphic sexual thalli and asexually propagating ones are mixed in uniform populations. Carpospores originating from sexual fusion develop into the diploid Conchocelis phase. Sporangia of asexual plants, though homologous in formation, produce spores of different kinds: aplanospores that give rise to the vegetative thallus directly (inP. umbilicalis, P. insolita n. sp. andP. ochotensis) and spores that develop into haploid Conchocelis (inP. laciniata and inP. linearis). P. laciniata — formerly considered synonymous withP. purpurea — is an independent species. “In an investigation into the life-history of an alga the aim should be to obtain a series of observations of the development of the thallus from the germinating spore and then of the development of the reproductive organs on the mature thallus. In cases where both sexual and asexual spores are formed the germination of both types of spore should be followed, ...” (Drew, 1954, p. 184)     

rbcL gene sequences reveal relationships among north-east Pacific species of Porphyra (Bangiales, Rhodophyta) and a new species, P. aestivalis

Phylogenetic analyses of the rbcL (chloroplast Rubisco large subunit) gene from 23 newly sequenced species of Porphyra, primarily from the north‐east Pacific, one Bangia and previously published sequences from both genera resolve relationships among most species of Porphyra and reveal five clades of species with Porphyra‐type morphologies among a number of Bangia lineages: (1) P. papenfussii V. Krishnam; (2) P. mumfordii S. C. Lindstrom et K. M. Cole and P. rediviva Stiller et Waaland together with a group of north Atlantic species, including the type of the genus, P. purpurea (Wahl‐enb.) C. Agardh; (3) P. cuneiformis (Setch. et Hus) V. Krishnam., P. occidentalis Setch. et Hus, P. schizo‐phylla Hollenb., and P. variegata (Kjellm.) Kjellm. and their Atlantic sibling species, all distromatic; (4) P. aestivalis sp. nov. and its north Atlantic sibling, P. birdiae C. D. Neefus et A. C. Mathieson; and (5) a speciose clade containing both Pacific and Atlantic representatives. Close relationships are confirmed between sibling species previously identified by iso‐zymes, morphology and chromosomal features. The morphologically similar dioecious P. pseudolanceolata V. Krishnam., P. conwayae (S. C. Lindstrom et K. M. Cole) stat. nov., and P. lanceolata (Setch. et Hus) G. M. Smith occur in a strongly supported subclade in clade 5 together with the monoecious P. fallax S. C. Lindstrom et K. M. Cole. Results presented here highlight the need for intensive taxon sampling and for examination of different parts of the genome to understand more fully relationships among species and higher level taxa in the Bangiales.     

126 Porphyra Birdiae Neefus et Mathieson (Bangiales, Rhodophyta): A New Species from the Northwest Atlantic

Recent studies combining biochemical, molecular, and traditional morphological and ecological traits have shown that some currently recognized species of the red algal genus Porphyra are actually "form species" or "complexes" comprising several morphologically similar but genetically distinct taxa. Conflicting reports of chromosome numbers and differences in DNA sequences reported for Porphyra purpurea (Roth) C. Agardh have raised suspicion that more than one taxon has been confused under this name in the Northwest Atlantic. We have identified one of these cryptic taxa and have recently described it as a new species, Porphyra birdiae . Like P. purpurea (Roth) C. Agardh, it has an ovate to broadly elongate, foliose blade with reproductive areas segregated by a distinct line into male and female sectors. While reproductive specimens have historically been confused with P. purpurea , non-reproductive specimens of P. birdiae have been incorrectly identified as P. umbilicalis Kützing. Although P. birdiae is morphologically similar to both of these species, sequences of SSU (nuclear small subunit rRNA gene) and rbc L (plastid ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit gene) indicate that it is not closely related to either one. Based on rbc L sequences, P. birdiae is closely related to P. aestivalis Lindstrom et Fredericq, a proposed new species from Alaska.     

Porphyra lilliputiana sp. nov. (Bangiales, Rhodophyta): A diminutive New Zealand endemic with novel reproductive biology

A new species of Porphyra, Porphyra lilliputiana, is described for the New Zealand region. This species is very small ([5] 10–20 [35] mm) and is found growing epiphytically, epilithically and epizoically on upper inter-tidal shores of moderate exposure. Field-collected material of P. lilliputiana possessed archeosporangia, endosporangia, spermatangia and zygotosporangia. In culture, archeospores vi/ere released and germinated to form thalli. Endosporangia either developed directly into thalli or released endospores which individually formed thalli. Zygotospores developed into the concho-celis phase, which formed conchosporangia. Released conchospores formed thalli. This species is distinguished by its small size, arrangement of reproductive cells, occurrence of endosporangia, dentate margin and habitat.     

Estimation of the degree of self-fertilization in Porphyra yezoensis (Bangiales,Rhodophyta)

Crosses between genotypically distinct thalli of the monoecious species Porphyra yezoensis were carried out using immature thallus fragments from green- and red-type color mutants and also wild-type thalli. As the genes governing the mutants are monogenic, recessive to the wild-type, and belong to the same linkage group, the degree of self-fertilization could be estimated based on the pigmentation of the resultant diploid conchocelis. The degree of self-fertilization in the cross between the green-type and the wild-type was 48.5–55.0%, and in the cross between the red-type and the wild-type was 45.1–56.5%. In the cross between the green- and red-type mutants, the degree of self-fertilization was 46.0–54.5% when the green-type was the female parent, and was 44.8–55.6% when the red-type was the female parent.     

Effect of harvest method and timing on yield and regeneration of Karengo (Porphyra spp.) (Bangiales,Rhodophyta) in New Zealand

Commercial interest in harvesting wild stocks ofPorphyra and concern for this prized resource by the Maori community highlighted the need to investigate the impact of harvest method and timing onPorphyra beds. Harvesting trials were carried out at two locations near Kaikoura (South Island) and one in Wellington (southern North Island) between June 1987 and September 1987. At each of five sampling sites, ten replicate sets of four quadrats were used to test the effects of harvest method and timing on yield and regeneration. The method of harvest had a major effect on the extent of regeneration: in quadrats in which thePorphyra had been cut with basal portions left intact there were harvestable plants within two months, whereas in quadrats which were cleared of allPorphyra there was very little growth after the same period. Harvests in the latter half of thePorphyra growing season gave greater yields at all sites except Wellington. Several species ofPorphyra were found to exist at the Kaikoura sampling sites and a single, different, species at the Wellington site. There were site to site differences in the yields.     

Induction and characterization of pigmentation mutants in Porphyra yezoensis (Bangiales, Rhodophyta)

Porphyra yezoensis Ueda conchospore germlings (1–4-cell stages) were treated with N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) for inducing mutations. Three kinds of color-mutated gametophytic blades, which were composed of the mutated cells wholly, sectorially or spottedly, were obtained; and most of them were sectorially variegated blades. The highest frequency of these mutated blades was 1.3%. Four different pigmentation mutant strains were obtained by regenerating single cells and protoplasts that were enzymatically isolated from the mutated sectors of the sectorially variegated blades. The mutants were relatively stable in color in both gametophytic blade and conchocelis phases. In the two phases, each mutant strain showed characteristic differences in the in vivo absorption spectra, and had different pigment contents of major photosynthetic pigments (chlorophyll a, phycoerythrin and phycocyanin) as compared with the wild-type and with each other. The gametophytic blades from the four mutant lines showed significant differences in growth and photosynthetic rates, when they were cultured in the same conditions. By crossing the mutant with the wild-type, it was found that the color phenotypes of two mutants reported above, were resulted from two mutations in different genes, respectively. This revised version was published online in August 2006 with corrections to the Cover Date.