• 생명과학회지
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• 제26권4호
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• pp.484-489
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• 2016

많은 생물체들은 다른 생물체들의 성장, 생존, 재생에 영향을 미치는 allelochemical 물질들을 생성함으로서 자신들의 영역을 유지 확장할 수 있다. 천연 생물촉진활성을 가진 allelochemicals을 찿기 위하여 18종의 흔한 해조류를 대상으로 실험실에서 편리하게 배양가능한 둥근돌김의 중성포자들로부터 가근 및 유엽의 형성 촉진효과를 탐색하였다. 그중 가장 활성이 높은 녹조류 청각의 추출물은 약 100 및 50 μg/ml 농도에서 최대 및 반 정도의 중성포자로부터 가근 형성 촉진효과를 나타내었다. 또한 청각 추출물은 중성포자 배양 초기에 가근형성, 가근갯수, 가근길이, 유엽형성, 유엽길이 등의 성장을 촉진시켰다. 이 같은 다른 해조류의 성장을 촉진시키는 allelochemicals 들은 천연 해조류 촉진제의 개발 및 유용 해조류 종들의 유지관리 등에도 활용될 가능성을 지닌다.

• ALGAE
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• 제20권4호
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• pp.353-361
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• 2005

Ascophyllum nodosum (L.) Le Jolis has a systemic infection with the ascomycete Mycophycias ascophylli (Cotton) Kohlmeyer and Volkmann-Kohlmeyer with which it establishese a mutualistic symbiosis. In addition, A. nodosum is the host for the obligate red algal epiphyte, Vertebrata lanosa (L.) Christensen. Using light and electron microscopy we describe morphological and cytochemical changes occurring as a consequence of rhizoid penetration of V. lanosa into cortical host tissue. Rhizoids induce localized cell necrosis based on physical damage during rhizoid penetration. Host cells adjacent to the rhizoid selectively undergo a hypersensitive reaction in which they become darkly pigmented and become foci for hyphal development. Light and electron microscopy show that M. ascophylli forms dense hyphal aggregations on the surface of the V. lanosa rhizoid and extensive endophytic hyphal growths in the rhizoid wall. This is the first morphological evidence of an interaction between M. ascophylli and V. lanosa. We speculate that M. ascophylli may be interacting with V. lanosa to limit tissue damage to their shared host. In addition, the fungus provides a potential pathway for the transfer of materials (e.g., nutrients and photosynthate) between the two phototrophs.

• ALGAE
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• 제25권3호
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• pp.141-153
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• 2010

Seagrass epiphyte blooms potentially have important economic and ecological consequences in Tampa Bay, one of the Gulf of Mexico's largest estuaries. As part of a Tampa Bay pilot study to monitor the impact of environmental stresses, precise characterization of epiphyte diversity is required for efficient management of affected resources. Thus, epiphyte diversity may be used as a rational basis for assessment of ecosystem health. In May 2001, epiphytic species encompassing green, brown and red macroalgae were manually collected from dense and sparse seagrass beds of Thalassia testudinum and Syringodium filiforme. A total of 20 macroalgal epiphytes, 2 Chlorophyta, 2 Phaeophyta, and 16 Rhodophyta, were found on T. testudinum and S. filiforme seagrass at the four sampling sites (Bishop Harbor, Cockroach Bay, Feather Sound, and Mariposa Key). The Rhodophyta, represented by 16 species, dominated the numbers of species. Among them, the thin-crusted Hydrolithon farinosum was the most commonly found epiphyte on seagrass leaves. Species number, as well as species frequency of epiphytes, is higher at dense seagrass sites than sparse seagrass sites. Four attachment patterns of epiphytes can be classified according to cortex and rhizoid development: 1) creeping, 2) erect, 3) creeping & erect, and 4) erect & holding. The creeping type is characterized by an encrusting thallus without a rhizoid or holdfast base. Characteristics of the erect type include a filamentous thallus with or without a cortex, and a rhizoid or holdfast base. The creeping and erect type is characterized by a filamentous thallus with a cortex and rhizoid. A filamentous thallus with a cortex, holdfast base, and host holding branch is characteristics of the erect and holdfast attachment type. This study characterized each species found on the seagrass for epiphyte identification.

• ALGAE
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• 제30권3호
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• pp.207-216
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• 2015

Caloglossa species occurs in freshwater streams around Southest Asia. We report it from 2 different riverine sites in Kerala, India. Tetrasporangiate plants were observed in field collections from the Periyar River and Chalakkudy River. The Chalakkudy isolate did not reproduce in culture but the Periyar isolate developed abundant tetrasporangial sori in culture. Many spores were discharged and most were abortive, but some germinated normally, sporelings forming male gametophytes with numerous spermatangial sori and females with many procarps, viable carposporophytes and some nonfunctional (no carpospores) pseudocystocarps. Some carpospores germinated forming new tetrasporophytes. Molecular evidence (28S rDNA and rbcL) placed the Indian specimens close to C. beccarii and C. fluviatilis. Considering the freshwater habitat and morphology of vegetative thalli (blade shape, rhizoid arrangement, and number of rhizoid filament per cell), the Indian specimens should be assigned to C. beccarii.

• Journal of Animal Science and Technology
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• 제45권6호
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• pp.1019-1030
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• 2003

본 연구는 국내의 재래 반추동물인 재래산양과 한우의 장내에 서식하며 강력한 섬유소를 분해하는 혐기 곰팡이를 탐색하고 분리하여 섬유소 분해 특성을 구명하고자 실시되었다. 산양의 반추위로부터 16종과 한우의 십이지장 소화물로부터 5종의 혐기 곰팡이를 분리하여 총 21종의 혐기성 곰팡이가 분리되었다. 섬유소 분해효소의 활력을 측정하여 그 중 섬유소 분해력이 높은 4종의 곰팡이에 대하여 광학현미경에 의한 형태학적 관찰을 기초로 동정 작업을 수행하였다. NLRI-M003은 monocentric 성장형태, 구형의 포자낭, filamentous rhizoid 및 유주자의 flagella가 다수인 Neocallimastix sp., NLRI-M014는 monocentric 성장형태, 방추형의 포자낭, filamentous rhizoid 및 유주자의 flagella가 단수인 Piromyces sp.로, NLRI-T004는 monocentric 성장형태, 난형의 포자낭, filamentous rhizoid 및 유주자의 fagella 수가 다수인 Neocallimastix sp.로 각각 확인되었다. NLRI-M001은 Orpinomyces sp. 와 유사한 것으로 추측되나 지금까지 밝혀진 곰팡이 이외에 다른 밝혀지지 않은 곰팡이가 존재할 가능성이 있을 것으로 평가되어 더욱 더 세부적인 조사가 필요하다고 사료되었다. 혐기 곰팡이의 섬유소 분해 특성을 조사하기 위해 산양의 반추위로부터 분리된 NLRI-M003 혐기 곰팡이 배양액을 2% 첨가하여 혼합 반추위 미생물의 in vitro 건물 분해율을 볏짚과 filter paper를 기질로 하여 조사하였다. 모든 처리구에서 혐기 곰팡이 배양액을 첨가한 첨가구가 무첨가구에 비하여 볏짚의 경우 약 4%이상(p〈0.05) 그리고 filtre paper를 기질로 사용시 11% 이상(p〈0.001)의 분해율이 증가하였다. 또한 CMCase와 xylanase 효소의 활력도 첨가구에서 증가하였으며 특히 반추위 곰팡이는 강력한 xylanase 효소활력이 높음을 보여주었다.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.163-168
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• 2012

The non-utilized biomass of the aquacultured seaweed Undaria pinnatifida, particularly the rhizoid, is an alternative source of arachidonic acid (AA). Of the five aquacultured kelps that were tested, U. pinnatifida yielded the highest amount of AA, which was isolated from the rhizoids. Its identity (C20:4 n-6) was confirmed from gas chromatography-mass spectrometry spectral data. The optimal conditions for post-harvest storage or pretreatment of the rhizoids in Provasoli's enriched seawater for AA extraction were determined to be pH 7.8, 2% $CO_2$-enriched air, 20 ${\mu}mol\;m^{-2}\;s^{-1}$ light, and $10^{\circ}C$. Under these conditions, the AA content after 1 day of storage was enhanced by up to 127%. In the absence of light under ambient aeration, the AA content after 1 day of storage diminished to 90%. Rhizoids collected late in the season (April and May) contained the highest amounts of AA (approximately 2.5 mg/g tissue).

• Journal of Plant Biology
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• 제28권1호
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• pp.45-55
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• 1985

홍조 Rhodochorton purpureum (Lightf.) Rosenvinge의 생식에 관한 연구를 일본 북해도산 식물을 중심으로 하여 수행하였다. 이 종은 주로 사분포자낭을 형성하지만 단포자낭은 자연상태나 실험실조건에서도 형성하지 않는다. Nemuro산 식물은 포자낭이나 배우자낭을 형성하지 않고 영양생식에 의한 번식을 하고 있다. 자연상태에서 영양생식은 사상체의 일부에 가근이 형성된 후에 그 부분이 떨어져나가 새로운 개체로 된다. Akkeshi와 Oshoro산(I) 식물에서 형성된 사분포자는 사분포자를 형성하는 식물체로 발달한다. 그러나 Muroran과 Oshoro산(II) 식물에서 형성된 사분포자는 배우체로 발달하는데, 이들 배우체는 사분포자낭과 웅성 또는 자성배우자낭을 형성하므로 배우체에 형성되는 사분포자낭은 유사분열에 의해서 형성되었으리라 생각한다.

• 한국균학회지
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• 제27권1호통권88호
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• pp.63-65
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• 1999

국내 미기록 진딧물병원성 곰팡이, Conidiobolus obscurus와 C. thromboides.를 1998년 6월경 수원 농업과학기술원내의 망초에 서식하는 진딧물 (Dactynotus sp.)에서 발견하였다. 두 종은 Conidiobolus속 곰팡이의 전형적인 둥근모양의 1차포자를 형성하며 전반적으로 유사한 형태를 나타내었다. 하지만 C. obscurus의 1차포자 크기는 C. thromboides의 것보다 월등히 큰 것으로 나타났다. 또한 C. thromboides는 rhizoid를 형성하며 분생자병이 점차적으로 가늘어지나 C. obscurus는 rhizoid를 형성하지 못하며 일정한 금기의 분생자병을 만드는 것이 뚜렷한 차이점이었다.

• 한국양식학회지
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• 제16권1호
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• pp.37-43
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• 2003

The present study reports morphology and developmental pattern off siliquosa cultured in a laboratory condition. The zygote was spherical with a diameter of 85 ${\mu}{\textrm}{m}$. During development the polarized zygote divided horizontally and the lower daughter cell divided horizontally into 2 cells. The upper cell was divided repeatedly in horizontal and vertical directions to form a cylinder-like structure, which subsequently developed into secondary and tertiary dichotomous branches. Optimum temperature for zygote release and fertilization was 25C. Injury inflicted by slicing was cured by epidermal differentiation, and adventitious branches; the branches emerging from the pith cells, however, developed no rhizoid. Adventitious branch formation rate was over 88% in all plates supplemented with 0.5 mg/L IAA and peaked at 98% under 0.5 mg/L IAA plus 0.5-5.0 mg/L NAA treatment. NAA stimulated the differentiation of adventitious branches at a wide range of concentrations, while IAA, 2,4-D and kinetin exhibited dose-dependent stimulation.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.78-83
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• 2000

Over twenty thousand types of bryohytes are existed in the world. Bryophytes are generally considered to be primitive plants and seriously neglected by even in botany area. Bryophytes includes mosses, liverworts, and hornworts. They thrive in humid environments and require water to survive. Some types, however, can recover after serious dehydration, even after years of complete dehydration. They generally absorb water and nutrients not from roots which is called rhizoid, but through entire body. The rhizoids are nonchlorophyllose fillamentous branches and attach the body to substratum such as soil and rocks. The attachment of mosses in soil surface provides a good protection from soil erosion by runoff water. In this presentation, reviewed and discussed are ecological characteristics and engineering perspectives of mosses, particularly with respect to soil and water conservation.