• Title/Summary/Keyword: Rhodophyta

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Temperature and Light Responses in Growth of Gracilaria verrucosa (Rhodophyta) and Its Potential for Mariculture in Korea

  • Kim Young Sik;Choi Han Gil;Kim Hyung Geun;Nam Ki Wan;Sohn Chul Hyun
    • Fisheries and Aquatic Sciences
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    • v.5 no.2
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    • pp.108-113
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    • 2002
  • Apical and subapical fragments of Gracilaria verrucosa (Hudson) Papenfuss (Rhodophyta) were cultured on a temperature-light gradient table with four temperature $(15,\;20,\;25\;and\;30^{\circ}C)$ and five light intensity $(20,\;40,\;60,\;80\; and\;100{\mu}mol\;photons\;m^{-2}s^{-l})$ regimes to examine growth responses. Their growth was measured weekly. Plant weight and lateral branch formation were affected by temperature and light intensity. As compared with other reports, relative growth rate (RGR) in both fragments was more or less high with 6.27 to $11.95\%$ $day^{-1}$. It was lowest at $15^{\circ}C$ with $20\mu mol$ photons $m^{-2}s^{-l}$, whereas, the highest value was recorded at $25^{\circ}C$ with $100\mu mol$ photons $m^{-2}s^{-l}$ During the experimental period, the growth pattern in G. verrucosa was significantly different between apical and subapical fragments, even though RGR based on weight was similar. Growth in apical fragments depended on elongation by apical growth. By contrast, subapical fragments mainly increased their weights by proliferation of lateral branch. This suggests that intercalary activity (e.g. lateral branch formation) is also an important means for growth of the thallus in Korean G. verrucosa. In conclusion, the relatively high growth potential with the intercalary activity in G. verrucosa will be helpful for mariculture in Korea.

New Record of some red algal species (Rhodophyta) from Korea

  • Jeong, So Young;Won, Boo Yeon;Kang, Pil Joon;Kang, Jeong Chan;Kim, Myung Sook;Nam, Ki Wan;Cho, Tae Oh
    • Journal of Ecology and Environment
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    • v.36 no.4
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    • pp.439-448
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    • 2013
  • Rhodophyta is one of major groups in the number of species and diversity of the marine algal flora. The occurrence of Korean 5 red algal species is reported for the first time on the list of Korean marine algal flora based on morphology: Ceramium pacificum, Cumathanmnion serrulatum, Gayliella fimbriata, Leptofauchea rhodymenioides, Sorella pulchra. Ceramium pacificum from Korea is recognized by complete cortication, many adventitious branches in a radial arrangement, 7-8 periaxial cells, and plant length of 1-2 cm. Cumathanmnion serrulatum is characterized by cartilaginous single main axis with a prominent midrib, serrulate blade, many higher orders of bladelets on each blade, and tetrasporagia produced near the midrib acropetally and then outwardly. Gayliella fimbriata is featured by clavate gland cell and 5-7 periaxial cells. Leptofauchea rhodymenioides is characterized by erect with flattened, dichotomously branched fronds, 1-2 cortical cells loosely arranged, 2-3 cell medullar layers with large colourless cells. Sorella pulchrais recognized by short branches produced alternately pinnate manner from margins of axial, mostly polystromatic frond, and tetrasporangial sori on the center of branches.

Taxonomic Characteristics of Peyssonnelia capensis Montagne(Peyssonneliaceae, Rhodophyta) from Jeju Island in Korea (제주도산 홍조 아프리카바다표고(Peyssonnelia capensis Montagne)의 분류학적 특성)

  • Kang, Seung-Ju;Lee, Jae-Wan;Lee, Wook-Jae;Oh, Yoon-Sik;Lee, Hae-Bok
    • ALGAE
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    • v.21 no.2
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    • pp.209-216
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    • 2006
  • The characteristics of Peyssonnelia capensis Montagne (Peyssonneliaceae, Rhodophyta) from Jeju Island were investigated in order to clarify the species entity and re-evaluate taxonomic position. The morphological variations of the Peyssonnelia capensis from Jeju Island were divided into two types, the thin thallus type and the thick thallus type. The thin thallus type is characterized by thin, soft, orbicular, slightly lobed thallus with entire to undulate margin, and compact rhizoids. The thick thallus type has thick and stiff thallus with sinuate margin and scattered rhizoids, and has more branches than the thin thallus type. The basal layer and the epithallium of thin thallus type are similar to those of thick thallus types in their structure. However, the hypothallial cells of the thick thallus type are longer than those of the thin thallus type. The erect filament of thick thallus type has more cells than those of the thin thallus type. Tetrasporangial nemathecia are distinctly protruded. Mature tetrasporangia of this species are divided cruciately into four spores as those of other Peyssonneliaceae. In addition to their morphological and anatomical distinctness between two types, the nucleotide sequence analyses of SSU and ITS2 region make no differences among populations from Jeju and other localities in Korea. Therefore these two morphological variation may not base on genetic variation.

Assessment of the macroalgal diversity of Kuwait by using the Germling Emergence Method

  • Amal H. Hajiya Hasan;Dhia A. Al-Bader;Steve Woodward;Csongor Z. Antony;Jared Kok Ong;Akira F. Peters;Frithjof C. Kupper
    • ALGAE
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    • v.38 no.2
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    • pp.127-139
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    • 2023
  • Cryptic stages of diverse macroalgae present in natural substrata, "the bank of microscopic forms", were isolated into clonal cultures and identified based on both morphological characteristics and DNA barcoding. Approximately 120 clonal isolates from 308 natural substratum samples were collected from the entire coastline of Kuwait. Amongst these isolates, 77 (64%) were identified through DNA barcoding using the nuclear ribosomal small subunit, RuBisCO spacer (ITS2, tufa, rbcL, psaA, and psbA) and sequencing. Twenty-six isolates (34%) were identified in the division Chlorophyta, 18 (23%) as Phaeophyceae, and 33 (43%) as Rhodophyta. For all DNA sequences in this study, species-level cut off applied was ≥98% homology which depend entirely on the markers used. Three putative new records of Chlorophyta new for the Arabian Gulf were made: Cladophora laetevirens (Dillwyn) Kützing, Ulva torta (Mertens) Trevisan and Ulvella leptochaete (Huber) R. Nielsen, C. J. O'Kelly & B. Wysor in Nielsen, while Cladophora gracilis Kützing and Ulva ohnoi M. Hiraoka & S. Shimada are new records for Kuwait. For Phaeophyceae, Ectocarpus subulatus Kützing and Elachista stellaris Areschoug were new records for the Gulf and Kuwait. In the Rhodophyta, Acrochaetium secundatum (Lyngbye) Nägeli in Nägeli & Cramer, Ceramium affine Setchell & N. L. Gardner, Gelidium pusillum var. pakistanicum Afaq-Husain & Shameel and Dasya caraibica Børgesen are new records for the Gulf and Kuwait, while the red alga Stylonema alsidii (Zanardini) K. Drew is a new record for Kuwait. Several isolates identified corresponded to genera not previously reported in Kuwait and / or the Arabian Gulf, such as Porphyrostromium Trevisan, a new genus from the Bangiales, and two unidentified species for the Planophilaceae Škaloud & Leliaert. The isolates cultivated from substrata enhance understanding of the marine macroalgal diversity in the region and confirmed that the Germling Emergence Method is suitable for determining the actual diversity of a given study area through isolation from cryptic life-history phases.