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1.
It had been demonstrated that individual or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monosproes,and that isolated cells develop in different way in liquid and on semi-solid media,The authors observed the ultrastructure of isolated vegetative cells cultured on semi-solid media and compared them with those of monospores and isolated cells cultured in liquid media,The results showed that subcellular struce-tures were quite different among cells in different conditions.In their development,isolated cells on semi-solid media did not show the characteristic subcellular eature of monospore formation ,such as production of fibrous vesicles,Callus-like cells formed on semi-solid media underwent a distinctive modification in cellular organization.They developed characteristic cell inclusions and a special 2-layer cell covering,Golgi bodies,ER ,starch grains,mitochondria,Vaculoes were not commonly found in them. 相似文献
2.
This research deals mainly with the use of the vegetative cells of a marine red algaPorphyra haitanensis (laver) as seeds and their culture into young thalli for further cultivation in the sea. The experimental process was as
follows. Enzymatically isolated vegetative cells were attached to rope substrates and cultured in the laboratory for a month
until they became about 0.2–0.5 cm long sporelings and were then attached (7–15 sporelings per cm of rope) to nets for removal
to the open sea for cultivation. A month after culturing, the thalli reached a maximum length of 50 cm (average of 20–30 cm).
The thalli grew faster as the water temperature dropped from 21°C to 17°C. It was proved that the vegetative cells isolated
from a small thallus about 5 cm long could grow up into normal thalli after being kept frozen for a year. The results of this
study show that vegetative cells can be used as new seeds to simplify the production of laver sporelings. This technique is
a significant advance in the field ofPorphyra culture. 相似文献
3.
ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｉｎｇｌｅｃｅｌｌｓａｎｄｐｒｏｔｏｐｌａｓｔｓｏｆＰｏｒｐｈｙｒａｇａｍｅｔｏｐｈｙｔｅｂｌａｄｅｓｃｏｕｌｄｄｅｖｅｌｏｐｉｎｔｏｐｌａｎｔｌｅｔｓｄｉ ｒｅｃｔｌｙｏｒｉｎｔｏｃａｌｌｕｓ ｌｉｋｅｃｅｌｌｓ (ＺｈａｏａｎｄＺｈａｎｇ ,1 981 ;Ｐｏｌｎｅ Ｆｕｌｌｅｒｅｔａｌ.,1 984 ;Ｃｈｅｎ ,1 989;ＷａｎｇａｎｄＹａｎ ,1 990 ;Ｇａｌｌｅｔａｌ.,1 993;Ｃｈｅｎ ,1 997;ＭｅｉａｎｄＦｅｉ,2 0 0 1 ) ,ａｎｄｔｈｅｉｒｇｒｏｗｔｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｕｎｄｅｒ… 相似文献
4.
It had been demonstrated that individual cells or protoplasts isolated from Porphyra thallus by enzyme could develop into normal leafy thalli in the same way as monospores, and that isolated cells develop in different way in liquid and on semi solid media. The authors observed the ultrastructure of isolated vegetative cells cultured on semi solid media and compared them with those of monospores and isolated cells cultured in liquid media. The results showed that subcellular structures were quite different among cells in different conditions. In their development, isolated cells on semi solid media did not show the characteristic subcellular feature of monospore formation, such as production of fibrous vesicles. Callus like cells formed on semi solid media underwent a distinctive modification in cellular organization. They developed characteristic cell inclusions and a special 2 layer cell covering. Golgi bodies, ER, starch grains, mitochondria. Vacuoles were not commonly found in them. 相似文献
5.
Yan Xinghong 《中国海洋湖沼学报》1993,11(3):235-244
Isolated protoplasts from thalli ofPorphyra haitanensis andPorphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV). Several types of color variants were observed among the protoplast
offspring. After treatment with colchicine: (1) 0.04–0.09% of red type variants inP. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of
sectors were 0.31–1.11% inP. yezoensis. After irradiation with UV: (1) 3.5–10.5% of red type variants inP. yezoensis were obtained: (2) 0.5–2.0% of red type variants and the variegated chimeral thalli composed of red type and wild type of
sectors were obtained inP. haitanensis. Colchicine and UV’s mutangenic effects onP. yezoensis protoplasts were stronger than those onP. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation
distance 5 cm). The red type variants induced by colchicine treatment grew faster than the wild type thalli. The clones of
vegetative propagation from protoplasts of red type variants were still red type thalli. The red type variants will be good
materials for genetic studies and improvement ofPorphyra strains. 相似文献
6.
There are many reports that cells (protoplasts) separated from the thallus ofPorphyra by enzyme can develop to normal leafy thalli in the same way as monospores. But there are few investigations on the subcellular
structure of the isolated vegetative cell for comparison with the subcellular structure of monospores. To clarify whether
the separated and cultured cells undergo the same or similar ultrastructure changes during culture and germination as monospores
undergo in their formation and germination, we observed their ultrastructure, compared them with those of the monospore and
found that the ultrastructure of separated and cultured cells did not have the characteristic feature as that of monospore
formation, such as production of small and large fibrous vesicles, but was accompanied by vacuolation and starch mobilization
like that in monospore germination. The paper also discusses the relations between monospores and separated and cultured cells.
Contribution No. 3875 from the Institute of Oceanology, Chinese Academy of Sciences.
Project 39770593 supported by NSFC; Project 96-C01-05-01 of the 9th Five-Year Plan supported by Science and Technology Commision
of China. 相似文献
7.
Bryopsis hypnoides Lamouroux is a unique intertidal siphonous green alga whose extruded protoplasm can aggregate spontaneously in seawater to form numerous new cells that can develop into mature algal thalli.In this study,the photosynthetic responses during dehydration of both the thalli and protoplasts isolated from B.hypnoides were measured using a Dual-PAM(pulse amplitude modulation)-100 fluorometer.The results show that the photosynthetic rates of B.hypnoides thalli were maintained for an initial period,beyond which continued desiccation resulted in reduced rates of PSI and PSII.However,the photosynthetic performances of the isolated protoplasts dehydrated in air(CO2 concentration 600±700 mg/L) showed a slight increase of Y(II) at 20% water loss,but the rates decreased thereafter with declining water content.When protoplasts were dehydrated in CO2 deficient conditions(CO2 concentration 40±80 mg/L),the values of Y(II) declined steadily with increased dehydration without an initial rise.These results indicated that the thalli and isolated protoplasts of this alga can utilize CO2 in ambient air effectively,and the photosynthetic performances of the isolated protoplasts were significantly different from that of the thalli during dehydration.Thus the protoplasts may be an excellent system for the study of stress tolerance. 相似文献
8.
There are many reports that cells (protoplasts) separated from the thallus of Porphyra by enzyme can develop to normal leafy thalli in the same way as monopores. But there are few investigations on the subcellular structure of the isolated vegetative cell for ccmparison with the subcellular structure of monospores. To clarify whether the separated and cultured cells undergo the same or similar ultrastructure changes during culture and germination as monospores undergo in their formation and germination, we observed their ultrastructure, ccxnpared them with those of the monospore and found that the ultrastructure of separated and cultured cells did not have the characteristic feature as that of monospore formarion, such as production of small and large fibrous vesicles, but was acccxnpanied by vacuolation andstarch mobilization like that in monospore germination. The paper also discusses the relations between monospores and separated and cultured cells. 相似文献
9.
严兴洪 《中国海洋湖沼学报》1993,(3)
Isolated protoplasts from thalli of Porphyra haitanensis and Porphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV ). Several types of color variants were observed among the protoplast offspring. After treatment with colchicine: (1) 0.04-0.09% of red type variants in P. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were 6.31- 1.11% in P. yezoensis. After irradiation with UV: (1) 3.5- 10.5% of red type variants in P. yezoensis were obtained: (2) 0.5-2-0% of red type variants and the variegated chimeral thalli composed of red type and wild type of sectors were obtained in P. haitanensis. Colchicine and UV's mutangenic effects on P. yezoensis protoplasts were stronger than those on P. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation distance 5 cm). The red type variants induced, by colchicine tr 相似文献
10.
Porphyra haitanensis andP. yezoensis are two mainPorphyra species cultured in China. Their life histories are slightly different. So far we have not observed thatP. haitanensis naturally produces monospores developing into thalli.P. yezoensis produces monospores which directly germinate into young thalli used in cultivation (Zeng, et al., 1985). Some somatic cells
inP. yezoensis develop in vitro into monospore-like cells which later grow into young thalli (Lu, 1983). Studies on whether or not somatic
cells inP. haitanensis can produce in vitro monospore-like cells that later grow into young thalli is important for understanding its life history
and for culturing new varieties. 相似文献
11.
Observation of female gamete (Carpogonia) germination of Porphyra yezoensis and P. oligospermatangia
Several papers have reported that part or whole leafy thallus seemingly consisting of zygotospores can give rise to both blades
and conchocelis in the same culture ofPorphyra. Study on samples of wild and cultivatedPorphyra yezoensis andP. oligospermatangia were conducted to clarify the origination of the young blades in the culture. It is confirmed that single cells on the blade
of both species, which normally intermixed with zygotospores, germinated into young blades. TEM and SEM observation has shown
that the single cells ofPorphyra yezoensis had typical features of female gamete (carpogonia) but archeospore. Therefore, the female gametes are responsible in developing
leafy thalli.
This project was sponsored by the NSFC (No. C-0205-05-39770593) 相似文献
12.
To investigate the genetic variation and population structure of Pacific herring in the Yellow Sea and the genetic differentiation between the Yellow Sea and the Sea of Japan,fragments of 479-bp mitochondrial DNA control region were sequenced for 110 individuals collected from three different periods in the Yellow Sea and one locality in the Sea of Japan.High haplotype diversity and moderate nucleotide diversity were observed in Pacific herring.AMOVA and exact test of population differentiation showed no significant genetic differentiations among the three populations of the Yellow Sea and suggested the populations can be treated as a single panmictic stock in the Yellow Sea.However,a large and significant genetic differentiation(WST50.11;P50.00) was detected between the populations in the Yellow Sea and the Sea of Japan.The high sea water temperature in the Tsushima Strait was thought a barrier to block the gene exchange between populations of the two sea areas.The neutrality tests and mismatch distribution indicated recent population expansion in Pacific herring. 相似文献
13.
A filamentous clone of Polysiphonia urceolata was regenerated from segments cut from the fronds of gametophytes. Unlike wild thalli with short virgate branchlets, the clone was filamentous with few branches. Many transparent trichoblasts arose from pericentral cells during the induction culture, but these were seldom observed during normal growth. The trichoblasts were uniseriate, often colorless, and formed lobed rhizoids rapidly when they came into contact with solid substrates. In addition to morphological characteristics, the photosynthetic properties and growth conditions of the clone differed from those of the mother plant. Cross-gradient light and temperature culture experiments revealed that the most favorable conditions for culture of the filamentous clone were 22°C and 95-120 μE/(m2-s) light intensity. The photosynthetic light saturation value for filaments was approx. 100 μE/(m2-s), which is far lower than that of wild thalli. These results could be used to develop techniques for mass cultures of P. urceolata in photobioreactors for production of seed stock or bioactive products. 相似文献
14.
Morphology and life history of a brown alga Scytosiphon lomentaria (Lyngbye) Link (Scytosiphonaceae, Phaeophyceae) were investigated from 2005 to 2009 in the coastal waters of Dalian, China. The erect thalli collected in the field were tubular, hollow, and commonly constricted at intervals. Ascocysts were presented. Plurilocular gametangia, which were positioned in continuous sori on the erect thallus surface, produced biflagellar gametes. Gametophytes were dioecious and gametes were nearly isogamous. Gametes fusion occurred in three types. Type one, female and male gametes fused directly while swimming; type two, female gamete settled first, with which a male one contacted and fused rapidly; type three, while settling adjacently, a male gamete’s entire protoplast moved slowly into the previously settled female one, with only an empty cell membrane left. In culture zygotes developed into crustose sporophytes that formed unilocular sporangia. Biflagellar zoospores developed into erect thalli that formed plurilocular gametangia. The results indicated that a periodical heteromorphic alternation history with haploid gametophyte generation and diploid sporophyte generation exists in S. lomentaria of the Dalian populations. 相似文献
15.
Effect of temperature and irradiance on growth and reproduction of Enteromorpha prolifera that bloomed offshore along the Qingdao coast in summer 2008, was studied. It was showed that E. prolifera propagated mainly asexually with specific growth rate （SGR） of 10.47 at 25℃/40 μmol m^-2s^-1. Under this condition, gametes with two flagellate formed and released in 5 days. At the beginning of the development, the unicell gamete divided into two cells with heteropolarity, and then the apical cell developed into thalli primordial cells, whereas the basal cell developed into rhizoid primordial cells. In 8-day culture, the monoplast gamete developed into juvenile germling of 240 μm in length. Unreleased gametes can develop directly within the alga body. E. prolifera could either reproduce through lateral branching or fragmenting except apomixis revealed by Microscopic observation. On aged tissue of E. prolifera, although the degraded pigments partially remained in faded algal filaments, numerous vegetative cells could still divide actively in the algal tissues. 相似文献
16.
A cell line,SHK,was derived from the kidney of spotted halibut Verasper variegates.The cell line was subcultured more than 40 passages in minimum essential medium(MEM)supplemented with fetal bovine serum(FBS)and 10 ng ml-1 basic fibroblast growth factor(bFGF).Cell morphology from primary culture and subculture was observed continuously by microscopy.The SHK cell line consisted predominantly of fibroblast-like cells.The cell line was able to grow between 20℃ and 30℃ with the optimum growth at 24℃ and with a reduced growth between 12℃ and 20℃.The growth rate of the cells increased as the proportion of FBS increased from 10% to 20% at 28℃ with optimum growth at the concentration of 20%.The doubling time of the cells was determined to be 44.8 h.Chromosome analysis revealed that 52% of the SHK cells maintained a normal diploid chromosome number (2n=46).The cells were successfully transfected with green fluorescent protein(GFP)reporter plasmids and the expression of GFP gene in the cells indicated the possible utility of the cells in gene expression studies.The cells were infected by lymphosystis disease virus(LCDV)and found to be susceptible to the virus in cytopathic effect(CPE)observation.The infection was confirmed by PCR and electron microscopy experiments,which proved the existence of the viral particles in the cytoplasm of the virus-infected cells. 相似文献
17.
The retinal structure and visual acuity in Japanese flounderParalichthys olivaceus at different stages of development were examined by light microscopy. The resolving power of the retina, the visual axis
and the best visual field were estimated based on the distribution of cone cells in the retina. The visual system of the larvae
appears poorly developed at hatching. The larvae with total length (TL) of less than 10 mm, have single cones only and the
eyes were well pigmented. At 10–11 mm TL, most single cones fused to form double cones, with the single and double cones forming
a mosaic pattern. From larvae to early juvenile the retina stretches, the cones increase in diameter and rods increase in
number. Based on the highest density of the cones in the ventro-temporal region, the visual axis was orientated upforward.
The resolving power of the retina in 40–530 mm TL Japanese flounder was found to range from 25.1 to 11.5 min. The results
indicated continual improvements in the visual system of the growing fish towards higher resolving power, visual acuity and
sensitivity.
Project 39970578 supported by the NSFC, and also supported by the Ministry of Education Foundation for University Key Teachers. 相似文献
18.
1 INTRODUCTION The red alga Gracilaria belongs to Gracilari- aceae, Gigartinales, Florideophyceae, and includes over 100 recorded species, wildly distributing in tropical and temperate regions (Oliveira and Plastino, 1994), and is useful for producing val… 相似文献
19.
Antioxidative capacity and enzyme activity in Haematococcus pluvialis cells exposed to superoxide free radicals 总被引：1，自引：1，他引：0
The antioxidative capacity of astaxanthin and enzyme activity of reactive oxygen eliminating enzymes such as superoxide dismutase
(SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) were studied in three cell types of Haematococcus pluvialis exposed to high concentrations of a superoxide anion radical (O2−). The results show that defensive enzymes and astaxanthin-related mechanisms were both active in H. pluvialis during exposure to reactive oxygen species (ROS) such as O2−. Astaxanthin reacted with ROS much faster than did the protective enzymes, and had the strongest antioxidative capacity to
protect against lipid peroxidation. The defensive mechanisms varied significantly between the three cell types and were related
to the level of astaxanthin that had accumulated in those cells. Astaxanthin-enriched red cells had the strongest antioxidative
capacity, followed by brown cells, and astaxanthin-deficient green cells. Although there was no significant increase in expression
of protective enzymes, the malondialdehyde (MDA) content in red cells was sustained at a low level because of the antioxidative
effect of astaxanthin, which quenched O2− before the protective enzymes could act. In green cells, astaxanthin is very low or absent; therefore, scavenging of ROS
is inevitably reliant on antioxidative enzymes. Accordingly, in green cells, these enzymes play the leading role in scavenging
ROS, and the expression of these enzymes is rapidly increased to reduce excessive ROS. However, because ROS were constantly
increased in this study, the enhance enzyme activity in the green cells was not able to repair the ROS damage, leading to
elevated MDA content. Of the four defensive enzymes measured in astaxanthin-deficient green cells, SOD eliminates O2−, POD eliminates H2O2, which is a by-product of SOD activity, and APX and CAT are then initiated to scavenge excessive ROS. 相似文献
20.
Observation of female gamete （Carpogonia） germination of Porphyra yezoensis and P. oligospermatangia
Several papers have reported that part or whole leafy thallus seemingly consisting of zygotospores can give rise to both blades and conchocelis in the same culture of Porphyra. Study on samples of wild and cultivated Porphyra yezoensis and P. oligospermatangia were conducted to clarify the origination of the young blades in the culture. It is confirmed that single cells on the blade of both species, which normally intermixed with zygotospores, germinated into young blades. TEM and SEM observation has shown that the single cells of Porphyra yezoensis had typical features of female gamete （carpogonia） but archeospore. Therefore, the female gametes are responsible in developing leafy thalli. 相似文献