• 한국자원식물학회지
• /
• 제32권6호
• /
• pp.735-742
• /
• 2019

This study investigated a suitable method that could be applied for Asian chain fern [Woodwardia japonica (L. f.) Sm.] to propagate gametophytes and promote sporophyte formation. The gametophytes used in all experiments were obtained from germinated spores in vitro and were subcultured at 8-week intervals. The most appropriate media for gametophyte propagation was identified by culturing 300 mg of gametophyte in Murashige and Skoog (MS) basal medium (1/8, 1/4, 1/2, 1, 2), and Knop medium for 8 weeks. As a result, fresh weight of the gametophyte was increased by 56.7-fold on MS medium. Moreover, antheridium formation as well as gametophyte growth was improved on MS medium, especially. To improve the sporophyte formation ex vitro, 1.0 g of gametophyte was ground with distilled water and spread on eight combinations onto four different culture mediums, such as bed soil, peat moss, perlite and decomposed granite. Then generation and growth of sporophytes were investigated after cultivation for 10 weeks. As a result of this experiment, peat moss had a promotive effect of sporophyte formation at single-use and mixed culture soils. In particular, a mixture of bed soil, peat moss and perlite in a 1:1:1 ratio (v/v/v) led to the accelerated formation (782.5 ea/pot) and the frond growth of sporophytes. This included increases in length and width of fronds. However, promotive effect of gametophyte growth and sporophyte formation was not found at single-use and treatment with high ratio of bed soil.

• 화훼연구
• /
• 제18권1호
• /
• pp.15-22
• /
• 2010

본 연구는 나무이끼(Climacium japonicum) 배우체의 기내증식에 영향을 미치는 몇 종류의 화학적 및 물리적 환경을 표준화하기 위하여 실시하였다. 초기 배양재료는 멸균한 배우체의 정단을 Knop 배지(1865)의 다량요소와 Nitsch와 Nitsch배지 (1956)의 미량요소를 첨가한 고체배지에 배양하여 획득하였다. 배우체 생산을 위해 좋은 배양재료를 얻기 위하여 다져진 배우체 및 shoot의 정단부와 기저부를 평가하였다. 배우체의 기내생산에 미치는 영향을 검정하기 위해 배지 7종류, 총질소 4농도, sucrose 5농도, 광도와 온도 등의 요인들을 분석하였다. Shoot의 정단부가 배우체 번식을 위해 사용한 3종류의 절편체들 중 가장 우수하였으며, Knop 배지(1865)의 다량요소와 Nitsch와 Nitsch배지 (1956)의 미량요소를 첨가한 배지가 다른 종류의 배지들에 비해 배우체의 증식에 효과적 이었다. Sucrose의 농도가 높아질수록 배우체의 신장 및 증식에 좋은 영향을 미쳤으며, 질소의 결핍 및 과다는 배우체의 생장을 억제하였다. 광도의 강약에 따라 배수체의 수, 길이 및 생체중에 큰 변화를 보였으며, 배우체 생장을 위해 최적의 광도는 3000-4000lx. 인 것으로 생각되었다. 고온 또는 저온 조 건은 배우체의 증식과 생산에 부정적인 영향을 미쳤다. 본 연구에 의해 개발된 생산과정의 단순화, 대량화 및 영양체의 고품질화는 효과적인 이끼의 기내배양 방법으로 생각되었다.

• ALGAE
• /
• 제21권1호
• /
• pp.109-124
• /
• 2006

Responses to various types of mechanically induced wounding were followed in the giant-celled Caulerpalean species, Derbesia tenuissima, using time-lapse video-microscopy. Gametophyte vesicle cells. Puncture wounding: the gametophyte cell seals the puncture in 5 min. This is followed by cycles of ruptures and sealing, ending with full recovery in 24 hrs. Cut wounding: the protoplast immediately retracts away from the wall and reforms an intact, deflated protoplast that expands to fill the original cell within 21 hrs. Crush wounding (internal). When retained within the cell wall many protoplast fragments condense, round up, and coalesce; the reconstituted protoplast expands until it attains complete recovery, filling the original cell shape in 12 hrs. Crush wounding (external). Protoplast fragments extruded from the crushed cell are more numerous and smaller taking longer to recover. Most fragments become spherical, transforming into small viable cells capable of reproduction in several days. Sporophyte filaments. Crush wounding creates many small fragments that initially condense, coalesce and then expand within the wall to restore a complete filament with normal cytoplasmic streaming within 5 hrs. Reproduction: gametophyte. Our culture isolates produce more females than males (30:1). Gametangia develop one day before discharge that occurs explosively (1/6 sec) at first morning light. The vesicle cell forms successive gametangia every 14 days. Sporophyte. Each sporangium develops on a lateral branch that becomes isolated by the creation of successive basal plugs. After cytoplasmic cleavage and differentiation the stephanokont spores are discharged. The spores settle quickly and germinate forming gametophyte cells.

• Molecules and Cells
• /
• 제39권10호
• /
• pp.768-775
• /
• 2016

The Arabidopsis female gametophyte contains seven cells with eight haploid nuclei buried within layers of sporophytic tissue. Following double fertilization, the egg and central cells of the gametophyte develop into the embryo and endosperm of the seed, respectively. The epigenetic status of the central cell has long presented an enigma due both to its inaccessibility, and the fascinating epigenome of the endosperm, thought to have been inherited from the central cell following activity of the DEMETER demethylase enzyme, prior to fertilization. Here, we present for the first time, a method to isolate pure populations of Arabidopsis central cell nuclei. Utilizing a protocol designed to isolate leaf mesophyll protoplasts, we systematically optimized each step in order to efficiently separate central cells from the female gametophyte. We use initial manual pistil dissection followed by the derivation of central cell protoplasts, during which process the central cell emerges from the micropylar pole of the embryo sac. Then, we use a modified version of the Isolation of Nuclei TAgged in specific Cell Types (INTACT) protocol to purify central cell nuclei, resulting in a purity of 75-90% and a yield sufficient to undertake downstream molecular analyses. We find that the process is highly dependent on the health of the original plant tissue used, and the efficiency of protoplasting solution infiltration into the gametophyte. By isolating pure central cell populations, we have enabled elucidation of the physiology of this rare cell type, which in the future will provide novel insights into Arabidopsis reproduction.

• ALGAE
• /
• 제34권2호
• /
• pp.153-162
• /
• 2019

Anthropogenic disturbances, including coastal habitat modification and climate change are threatening the stability of kelp beds, one of the most diverse and productive marine ecosystems. To test the effect of temperature and irradiance on the microscopic gametophyte and juvenile sporophyte stages of the rare kelp, Saccharina angustissima, from Casco Bay, Maine, USA, we carried out two sets of experiments using a temperature gradient table. The first set of experiments combined temperatures between $7-18^{\circ}C$ with irradiance at 20, 40, and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$. The second set combined temperatures of $3-13^{\circ}C$ with irradiance of 10, 100, and $200{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Over two separate 4-week trials, in 2014 and again in 2015, we monitored gametogenesis, the early growth stages of the gametophytes, and early sporophyte development of this kelp. Gametophytes grew best at temperatures of $8-13^{\circ}C$ at the lowest irradiance of $10-{\mu}mol\;photons\;m^{-2}\;s^{-1}$. Light had a significant effect on both male and female gametophyte growth only at the higher temperatures. Temperatures of $8-15^{\circ}C$ and irradiance levels of $10-100{\mu}mol\;photons\;m^{-2}\;s^{-1}$ were conditions for the highest sporophyte growth. Sporophyte and male gametophyte growth was reduced at both temperature extremes-the hottest and coldest temperatures tested. S. angustissima is a unique kelp species known only from a very narrow geographic region along the coast of Maine, USA. The coupling of global warming with high light intensity effects might pose stress on the early life-history stages of this kelp, although, as an intertidal species, it could also be better adapted to temperature and light extremes than its subtidal counterpart, Saccharina latissima.

• ALGAE
• /
• 제26권1호
• /
• pp.51-60
• /
• 2011

Similar to other species of Gigartinaceae Chondrus crispus has an alternation of perennial, isomorphic gametophytic and sporophytic generations. As these two generations co-exist independently within populations and obtain their resources in a similar manner, intraspecific competition is expected. In populations within the southern Gulf of St. Lawrence, fronds of both generations of C. crispus occur in similar numbers. This equivalency can be related to substratum instability, where the population is dynamic with a high turn-over rate of genets. These observations support a stochastic hypothesis to account for distribution of gametophytes and sporophytes in this area. Along the Atlantic coast of Nova Scotia, where the substratum is stable, gametophytes are overwhelmingly predominant. Gametophytic predominance is greatest in the lower littoral zone where C. crispus is abundant and space is limited. Under the fucoid canopy where "free-space" exists, the gametophyte to sporophyte ratio is lower. Gametophytic and sporophytic fronds are distributed equally among different size-classes and size-distribution is not considered a competitive factor. Previous studies have shown that sporophytic fronds of C. crispus are more susceptible to infections by endophytic algae and other pathogens, and are more heavily grazed by herbivores than are gametophytic fronds. Thus, mechanistic factors are strongly implied in the selection of gametophytes in the Atlantic population.

• 식물분류학회지
• /
• 제32권4호
• /
• pp.467-480
• /
• 2002

현호색속 6종의 대배우자체 발달과정이 공초점현미경(LSCM)과 광학현미경으로 비교, 관찰되었다; 흰현호색, 왜현호색, 섬현호색, Corydalis nobilis, C. solida, C. ophiocarpa. 포원세포는 돌출된 주심조직의 단층 표피 밑에 존재하는 측벽세포의 최외곽층 세포들에서 하나가 기원하였으며, 직접 대포자모세포로서 작용하였다. 대포자모세포는 대포자발생과정을 통하여 연속적으로 2회 분열한 후 선상의 4분체가 되었으며, 이들 중 주공쪽의 3개는 퇴화하고 합점쪽의 1개만이 기능성 대포자로 발달하였다. 자성배우자체의 발달 유형은 단포자성, 마디풀형(Polygonum type)이었다. 개화 전 자성배우자체는 성숙하였고, 따라서 성숙된 배낭은 3개의 세포로 이루어진 난장치, 거대한 핵이 있는 3개의 대형 반족세포 및 2차핵이 존재하는 1개의 중앙세포로 구성되어 있었다. 반족세포 흡기는 반족세포의 정단에서부터 각각 발달되었으며, 주공쪽으로 신장되어 난장치와 접촉하였다. 2개의 조세포는 보통 퇴화된 상태로 관찰되었으며, 이때 반족세포 흡기의 정단은 퇴화된 조세포와 연결되었다. 7-세포성 자성배우자체의 발달과정상 특징은 조사된 모든 종에서 공통적이었으나, 배낭의 형태는 흰현호색, 섬현호색, C. solida 및 C. ophiocarpa에서는 난형이었으며, 왜현호색에서는 반곡형인 반면 C. nobilis에서는 다소 납작한 난형이었다. 또한 대포자낭의 유형은 모든 종에서 도생배주였으나 왜현호색에서는 만곡배주였다.

• 한국해양생명과학회지
• /
• 제7권2호
• /
• pp.86-93
• /
• 2022

미역(Undaria pinnatifida) 포자를 사용한 생태독성 시험법은 연중 상시 이용하기에 어렵다. 미역의 암배우체는 실험실에서 배양할 수 있기 때문에, 포자의 단점을 보완하고 상시 생태독성 시험에 사용할 수 있다. 따라서 미역의 암배우체를 생태독성 시험에 활용하기 위해 다양한 환경조건에 노출된 미역의 암배우체 생존율과 상대성장률의 변화를 분석하였다. 미역 암배우체는 염분(5~40 psu), 온도(5~30℃), pH (2~10), 광량(0~120 μmol photon m^-2 s^-1)에 노출되었다. 암배우체의 생존율은 최고 평균값을 기준으로 온도 20℃, 염분 27.5 psu, pH 8, 광량 30 μmol photon m^-2 s^-1에서 가장 높았다. 상대성장률은 최고 평균값을 기준으로 온도 15℃, 염문 35 psu, pH 9, 광량 60 μmol photon m^-2 s^-1에서 가장 높았다. 본 연구결과를 통해 미역 암배우체의 생존율과 상대성장률을 활용하여 연안환경을 상시 신속하게 평가하기 위한 효율적인 방법으로 활용이 기대된다.

• Journal of Plant Biology
• /
• 제27권4호
• /
• pp.233-239
• /
• 1984

Reproductives structures of Pachymeniopsis elliptica (Holmes) Yamade (Rhodophyta, Grateloupiaceae) are investigated. In female gametophyte the carpogonial branch and auxiliary cell are produced in separate accessory branch system, the primary ampullar filament originated from mid-cortical layer. After fertilization, auxiliary cell joined with connecting filament becomes a fusion cell by fusing with several neighboring ampullar cells. The fusion cell produces a gonimoblast initial. It divides into gonimoblast cells, which later convert to carposporangia. In male gametophyte superficial cortical cells of vegetative filament produce two spermatangial mother cells which cut off up to three spermatangia respectively. Tetrasporangial initials are formed from the 6th to 12th cells of the cortical layer in tetrasporophyte, and divided cruciately to form tetrasporangium. Some of the sporangia are, however, divided zonately.

• 한국약용작물학회지
• /
• 제12권3호
• /
• pp.209-213
• /
• 2004

토천궁은 개화는 되지만 종자 결실이 이루어지지 않아 주로 종근이나 뇌두에 의해 번식하므로 번식율이 매우 저조한 특성이 있다. 따라서 이의 원인을 구명하고자 자웅배우체 형성과정과 자가수분을 통한 수정현상을 보기 위하여 조사하였던 바 그 결과는 다음과 같다. 토천궁은 대소포자에서 감수분열이 정상적으로 이루어지고 배낭형성에서 난장치는 50% 정도가 정상적으로 이루어지고, 화분형성에서는 90%이상이 잘 이루어졌다. 토천궁의 배낭은 주심조직의 세포가 작아 모든 기관분열에서 관찰하기가 어려웠고 특히 토천궁은 배낭 형성체가 난장치로 발달되는 꽃은 거의 없었으며 화분립은 일부가 형성 되었다.