• ALGAE
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• 제26권1호
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• pp.61-71
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• 2011

Thirty populations of Chondrus crispus Stackhouse from Nova Scotia were collected during the years 1993 to 2011. Taken from estuaries, wave exposed open coasts, high intertidal rock pools and shallow subtidal habitats, the populations were evaluated for relative abundance of tetrasporophytic and gametophytic life history phases. Over 2,800 thalli were characterized using the resorcinol-acetal test to distinguish the kappa- and lambda-carrageenan containing fronds of gametophytes and tetrasporophytes, respectively. These populations had $77{\pm}5%$ gametophytes (mean ${\pm}95%$ confidence interval), with most populations having gametophyte : sporophyte ratios ranging from 2 : 1 to 9 : 1. No population had a dominance of tetrasporophytes, although two populations had 1 : 1 ratios. A meta-analysis of our data along with previously published accounts showed no significant changes in gametophyte dominance with respect to hypothesized gradients of wave exposure, salinity, or water depth. Significant changes occurred in ratios at five sites where replicate sampling occurred in different years. We conclude that C. crispus in Maritime Canada has a natural ratio of 3 : 1 or greater in stable conditions, and that lower ratios represent recovery from disturbance in which bare substratum is created that is subsequently colonized by carpospores from remaining gametophytic thalli.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.156-164
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• 2002

Enteromorpha prolifera of the isomorphic diploid sporophyte and the haploid gametophyte generations inhabit rocks, tidal flats and tidal pools in the middle parts of intertidal zones. In this experiment, their thalli were observed by bare eyes from October and experienced $74\pm16.5cm$ maximum growth the following March and April. The rate of occurrence of the thalli per month was highest in March, while their biomass peaked at $1,464\pm41.5 g/m^2$ in Jangheung in April. Genetic similarity was investigated samples of E. prolifera collected from Muan, Wando, Jangheung, Yosu and Jinhae, at the south coast of Korea. Random amplified polymorphic DNA (RAPD) markers were used. For the RAPD analysis, 3 ng of the DNA extracted from the thalli using he phenol/chloroform method was amplified by PCR with a 25 {\mu}L$ reaction solution, arbitrary primers and 36 cycles. Among the 60 primers used, 31 yielded products, most of which showed diverse electrophoresis patterns. Similarities among the groups compared ranged from 0.37 to 0.58. We conclude that the use of RAPD analysis is appropriate to characterize the genetic variability of this commercial species along its geographical distribution.

• Molecules and Cells
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• 제43권5호
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• pp.448-458
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• 2020

T-DNA insertional mutations in Arabidopsis genes have conferred huge benefits to the research community, greatly facilitating gene function analyses. However, the insertion process can cause chromosomal rearrangements. Here, we show an example of a likely rearrangement following T-DNA insertion in the Anti-Silencing Function 1B (ASF1B) gene locus on Arabidopsis chromosome 5, so that the phenotype was not relevant to the gene of interest, ASF1B. ASF1 is a histone H3/H4 chaperone involved in chromatin remodeling in the sporophyte and during reproduction. Plants that were homozygous for mutant alleles asf1a or asf1b were developmentally normal. However, following self-fertilization of double heterozygotes (ASF1A/asf1a ASF1B/asf1b, hereafter AaBb), defects were visible in both male and female gametes. Half of the AaBb and aaBb ovules displayed arrested embryo sacs with functional megaspore identity. Similarly, half of the AaBb and aaBb pollen grains showed centromere defects, resulting in pollen abortion at the bi-cellular stage of the male gametophyte. However, inheritance of the mutant allele in a given gamete did not solely determine the abortion phenotype. Introducing functional ASF1B failed to rescue the AaBb- and aaBb-mediated abortion, suggesting that heterozygosity in the ASF1B gene causes gametophytic defects, rather than the loss of ASF1. The presence of reproductive defects in heterozygous mutants but not in homozygotes, and the characteristic all-or-nothing pollen viability within tetrads, were both indicative of commonly-observed T-DNA-mediated translocation activity for this allele. Our observations reinforce the importance of complementation tests in assigning gene function using reverse genetics.

• ALGAE
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• 제29권3호
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• pp.203-215
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• 2014

As global warming continues over the coming century, marine organisms will experience a warmer, more acidic ocean. Although these stressors may behave antagonistically or synergistically and will impact organisms both directly (i.e., physiologically) and indirectly (i.e., through altered species interactions), few studies have examined the complexities of these effects in combination. To address these uncertainties, we examined the independent and combined effects of elevated temperature and $pCO_2$ on the physiology of the adult sporophyte stage of giant kelp, Macrocystis pyrifera, and the grazing of the purple sea urchin Strongylocentrotus purpuratus. While elevating $pCO_2$ alone had no effect on M. pyrifera growth or photosynthetic carbon uptake, elevating temperature alone resulted in a significant reduction in both. However, when M. pyrifera was grown under elevated temperature and $pCO_2$ together, growth and photosynthetic carbon uptake significantly increased relative to ambient conditions, suggesting an interaction of these factors on photosynthetic physiology. S. purpuratus held under future conditions generally exhibited reduced growth, and smaller gonads than urchins held under present-day conditions. However, urchins fed kelp grown under future conditions showed higher growth rates, partially ameliorating this effect. Feeding rates were variable over the course of the experiment, with only the first feeding rate experiment showing significantly lower rates for urchins held under future conditions. Together, these data suggest that M. pyrifera may benefit physiologically from a warmer, more acidic (i.e., higher $pCO_2$) ocean while S. purpuratus will likely be impacted negatively. Given that kelp-urchin interactions can be important to kelp forest structure, changes to either of these populations may have serious consequences for many coastal environments.

• Ocean and Polar Research
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• 제37권3호
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• pp.201-209
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• 2015

To examine the effects of increased $CO_2$ concentration and seawater temperature on the photosynthesis and growth of forest forming Ecklonia cava (Laminariales, Phaeophyta), sporophytic discs and gametophytes were cultured under three $pCO_2$ concentrations (380, 750, 1000 ppm), four temperatures (5, 10, 15, $20^{\circ}C$ for sporophytes; 10, 15, 20, $25^{\circ}C$ for gametophytes), and two irradiance levels (40, $80{\mu}mol$ photons $m^{-2}s^{-1}$) for 5 days. Photosynthetic parameter values ($ETR_{max}$, $E_k$, and ${\alpha}$) were generally higher as sporophytic discs were grown under low temperature and increased $CO_2$ concentration at 750 ppm. However, photosynthesis of Ecklonia sporophytes was severely inhibited under a combination of high temperature ($20^{\circ}C$) and 1000 ppm $CO_2$ concentration at the two photon irradiance levels. The growth of gametophytes was maximal at the combination of 380 ppm (present seawater $CO_2$ concentration) and $25^{\circ}C$. Minimal growth of gametophytes occurred at enriched $pCO_2$ concentration levels (750, 1000 ppm) and high temperature of $25^{\circ}C$. The present results imply that climate change which is increasing seawater temperature and $pCO_2$ concentration might diminish Ecklonia cava kelp beds because of a reduction in recruitments caused by the growth inhibition of gametophytes at high $pCO_2$ concentration. In addition, the effects of increased temperature and $pCO_2$ concentration were different between generations - revealing an enhancement in the photosynthesis of sporophytes and a reduction in the growth of gametophytes.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.71-71
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• 2018

본 연구는 각시톱시네고사리(Dryopteris hangchowensis Ching)의 전엽체 증식 및 포자체 형성을 위한 번식방법을 구명하고자 수행되었다. 각시톱지네고사리의 식물체를 무가온 온실에 재배하면서 포자를 채취하였으며, 수집된 포자는 기내에서 발아시켜 전엽체를 획득한 다음 계대배양하면서 실험의 재료로 사용하였다. 전엽체 대량증식을 위하여 1/4, 1/2, 1배로 조절한 MS배지와 Knop배지를 조성하였다. 이후 전엽체 300mg을 균일하게 다져 조성된 배지에 8주간 배양하였다. 연구의 결과, 전엽체의 생체중은 1/2MS와 1/4MS에서 3.4g으로 가장 많이 증가하였다. 현미경 관찰의 결과, 두 배지 모두 정상적인 전엽체의 형태로 발달하였으며, 생육도 양호하였다. 포자체 형성을 위한 적정 배양토의 혼합조건을 확인하고자 원예상토, 피트모스, 펄라이트 및 마사토의 혼합비율을 5종류로 달리하여 조성하였다. 준비된 배양토를 사각분($7.5{\times}7.5{\times}7.5cm$)에 충진 후 기내 배양한 전엽체 1g과 증류수를 함께 10초간 분쇄하여 토양표면에 균일하게 분주한 다음 12주간 재배하였다. 연구의 결과, 원예상토, 피트모스, 펄라이트를 1:1:1(v:v:v) 비율로 혼합한 토양에서 포트 당 223.7개로 가장 많은 포자체가 형성되었다. 또한 형성된 포자체의 생육을 조사한 결과, 상기 토양에서 생체중, 엽수, 엽장, 엽폭, 근수, 근장 및 SPAD value 등의 생육수치가 우수하였다. 따라서 각시톱시네고사리의 전엽체 증식에 적합한 배지는 경제성과 생육수준을 고려하여 1/4MS 배지가 적합하며, 포자체 대량생산을 위해서는 원예상토, 피트모스, 펄라이트를 1:1:1(v:v:v)로 혼합한 토양이 적합하다고 판단되었다.

• 한국자원식물학회지
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• 제19권2호
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• pp.360-364
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• 2006

도깨비고비와 참쇠고비의 포자발아에서 얻은 전엽체를 균질화하여 배양함으로써 전엽체 개체발생과 포자체 형성과정을 연구하였다. 배양 2주일이 지나자 균질화한 전엽체 세포들이 일차원의 필라멘트 형태를 형성하였고, 4주일째에는 다수의 가지를 뻗은 형태의 전엽체가 출현하였다. 배양 6주일째에 apical notch가 발달된 전엽체가 형성되었는데. 중심부에는 분열조직이 발달되었다. 8주의 배양기간이 지나자 전엽체의 중심부에서 장란기의 형성 없이 무수정생식에 의한 bud가 관찰되었다. 10주일이 지나자 무수정생식에 의한 bud는 포자체로 발달되었는데, flow cytometric 분석 결과 도깨비고비와 참쇠고비 모두에서 전엽체와 포자체는 동일한 ploidy level을 지닌 것으로 확인되었다. 이는 도깨비고비뿐만 아니라 참쇠고비 또한 무수정생식을 하는 양치식물임을 증명하는 결과로 생각된다.

• 한국자원식물학회지
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• 제19권2호
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• pp.265-272
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• 2006

본 연구는 포자체 배양을 통하여 참쇠고비의 효율적인 번식방법을 구하고자 수행되었다. 배양절편의 기원(근경, 엽병, 엽신)과 절편의 균질화가 신초 계생에 미치는 영향을 조사한 결과, 오직 근경 조직에서만 기관발생능력이 관찰되었고, 식물체 재생은 배양재료를 균질화함으로써 더욱 촉진되었다. MS배지의 무기물 농도를 2배로 첨가한 배지에서 신초의 증식과 생장이 활발히 이루어졌다. 신초 재생에 적합한 배지의 질소함량은 MS배지의 1/2배 수준 이었고, 적정 sucrose농도는 1%였다. 또한 배지에 $NaH_2PO_4$를 첨가함으로써 재생된 식물체의 생육이 전반적으로 촉진되었다. 근경절편의 기관형성능력은 kinetin과 IBA를 혼용 처리함으로써 촉진되었으며, $0.1\sim0.2%$의 활성탄과 생장조절물질을 혼용 처리한 결과, 다수의 싹이 뭉친 듯이 보이는 primordia 형태의 발달이 억제되었고, 포자체의 정상적인 형태형성이 향상되었다.

• 한국수산과학회지
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• 제44권1호
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• pp.71-77
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• 2011

The effects of temperature, light, and salinity on the growth of Costaria costata and Undaria pinnatifida juveniles were examined in laboratory cultures. In a cultivation farm, the monthly yield and density were also investigated between December and April for C. costata and between December and March in 2007 and 2008 for U. pinnatifida. The relative growth rates (RGRs) were greater at $20{\sim}60\;{\mu}mol$ photons $m^{-2}s^{-1}$ than at low ($0{\sim}10\;{\mu}mol$ photons $m^{-2}s^{-1}$) and high ($100{\sim}180\;{\mu}mol$ photons $m^{-2}s^{-1}$) irradiance levels. The optimal growth conditions for the two species were $17^{\circ}C$, 35 psu, $60\;{\mu}mol$ photons $m^{-2}s^{-1}$, and a daylength of 12 h, indicating that C. costata and U. pinnatifida have very similar growth responses to temperature, light, and salinity. However, the growth responses of the two species to various environmental factors were different; C. costata grew faster than U. pinnatifida but the latter species grew well at low salinity. The monthly yield of C. costata and U. pinnatifida increased steadily over the study period, and it was maximal in March for both species, but the yield of U. pinnatifida was greater than that of C. costata.

• 한국식품과학회지
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• 제36권6호
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• pp.1008-1013
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• 2004

국내산 주요 갈조류 18종의 추출용매 및 온도에 따른 항혈액응고 활성을 측정한 결과 미역, 다시마, 감태, 대황, 곰피, 톳, 괭생이 모자반의 열수 추출물의 APTT가 190.0초 이상으로 활성이 높았으며, 이 때의 추출온도는 $90^{\circ}C$였다. 감태의 에탄올 불용성분의 항혈액응고 활성은 $500\;{\mu}g/mL$에서 에탄을 가용성 물질에 비하여 2배 이상 증가하였으며, 에탄을 불용성분의 분자량에 따른 항혈액응고 활성은 $100\;{\mu}g/mL$ 농도에서 EKJ-eim 1(100 kDa 이상)이 190초 이상으로 EKJ-eim 2(100-50 kDa) 및 EKJ-eim 3(50-10 kDa)에 비해 좋았으며, 이 분회의 화학적 조성성분은 fucose, xylose, mannose, galactose, glucose, sulfate로 구성되어 있으며, 몰비는 1 : 0.05 : 0.10 : 0.15 : 0.17 : 1.46으로 2 mole의 fucose에 3 mole의 황산기가 결합되어 있는 산성다당임을 확인하였다.