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1.
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   

2.
Kong  Ning  Liu  Xiao  Li  Junyuan  Mu  Wendan  Lian  Jianwu  Xue  Yanjie  Li  Qi 《中国海洋湖沼学报》2017,35(5):1248-1258
Temperature and salinity are two of the most potent abiotic factors infl uencing marine mollusks.In this study,we investigated the individual and combined ef fects of temperature and salinity on the survival and growth of juvenile Pacifi c abalone,Haliotis discus hannai Ino,and also examined the DNA methylation alteration that may underpin the phenotypic variation of abalone exposed to dif ferent rearing conditions.The single-factor data showed that the suitable ranges of temperature and salinity were 16–28°C at a constant salinity of 32,and 24–40 at a constant temperature of 20°C,respectively.The two-factor data indicated that both survival and growth were signifi cantly af fected by temperature,salinity and their interaction.The optimal temperature-salinity combination for juveniles was 23–25°C and 30–36.To explore environment-induced DNA methylation alteration,the methylation-sensitive amplifi ed polymorphism(MSAP)technique was used to analyze the genomic methylation profi les of abalone reared in optimal and adverse conditions.Neither temperature nor salinity induced evident changes in the global methylation level,but 67 and 63 dif ferentially methylated loci were identifi ed in temperature and salinity treatments,respectively.The between-group eigen analysis also showed that both temperature and salinity could induce epigenetic dif ferentiation in H.discus hannai Ino.The results of our study provide optimal rearing conditions for juvenile H.discus hannai Ino,and represent the fi rst step toward revealing the epigenetic regulatory mechanism of abalone in response to thermal and salt stresses.  相似文献   

3.
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4.
The wild Porphyra yezoensis collected from the Qingdao coast was used to prepare protoplasts by enzyme digestion. The pure line was constructed by cultivating the protoplasts. The 18S rDNA of the P. yezoensis pure line was cloned and sequenced. Sequence analysis was executed for this sequence and other 22 sequences retrieved from GenBank. A phylogenetic tree was constructed using the neighbor-joining method. The results revealed a high diversity of 18S rDNA sequences in genus Porphyra and the considerable variation of 18S rDNA sequences in different strains of the same species P. yezoensis and P. tenera. Significant difference of 18S rDNA sequence was observed between P. yezoensis from Qingdao, China, and the two strains of P. yezoensis from Japan, but the three strains of P. yezoensis formed a stable clade in the phylogenetic tree. These results indicate the possibility of interspecies and intraspecies discrimination of Porphyra using the 18S rDNA sequences.  相似文献   

5.
Mei  Kuang  Su-juan  Wang  Yao  Li  Da-leng  Shen  Cheng-kui  Zeng 《中国海洋湖沼学报》1998,16(1):56-61

Electroporation, PEC, PEG plus electroporation and Biolistics methods were tested in gene transformation ofP. yezoensis. The exogenousgus was from plasmid of pBI121 and pCAMBIA1301, both contain the CaMV35S promoter. The receptors included the protoplasts, tissues and free-living conchocelis filaments ofP. yezoensis. Several factors, for example, the voltage, capacitance and bivalent cations, etc., were studied. Results show that these four methods are all efficient for gene transformation inP. yezoensis; and that PEG is the best one, with transformation efficiency of up to 4×10−5. GUS activity was detected 26 days after transformation by using PEG method.

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6.
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   

7.
Cryopreservation of Porphyra yezoensis conchocelis was conducted with cryoprotectants and a proposed pretreatment procedure and thawing methods explored. Six cryoprotectants combined by DMSO with ethylene glycol （EG）, propylene glycol （PEG）, sorbitol and sucrose were developed. The effect of prefreezing at -40℃ or -20℃ for different time durations was compared and the thawing methods were screened. It was shown that the cryoprotectant including 10% DMSO with 0.5 molL^-1 sorbitol exhibited the optimal effect. The ideal pretreatment was that conchocelis segments were stayed for 20min at -40℃ before stored in liquid nitrogen, and 40℃ water bath was proper for quick thawing. The highest recovery rate of cryopreserved P. yezoensis conchocelis reached 89.41%.  相似文献   

8.
The major population of the veined rapa whelk Rapana venosa(Valenciennes, 1846), which is an important fishery resource, is facing a large decline in China. We studied the effects of incubation temperature(16–34℃ at salinity 30) and salinity(5–45 at 25℃) on the incubation period and subsequent larval development. In the temperature experiment, the shortest incubation period was 12 days at 34℃, the lower temperature limit was 16℃, the longest mean shell length(1 193±17 μm) occurred at 25℃ and the highest survival rate 72.28%±5.62% was observed at 28℃. In the salinity experiment, the shortest incubation period was 15 days at 25. The salinity tolerance range was 15–40, the longest mean shell length(855±9 μm) and the highest survival rate 72.93%±4.85% were both observed at 35. This study demonstrated that, during the egg–mass stage, temperature and salinity regimes infl uence later growth and survival of larvae. These observations deepen our understanding of the ecology and conservation of natural populations of Rapana venosa.  相似文献   

9.
In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chain reaction (PCR) based on the analysis of P. yezoensis ESTs from dbEST database. The result shows that the full-length cDNA of CaM consists of 603 bps including an ORF encoding for 151 amino acids and a terminate codon UGA, while the length of genomic sequence is 1231 bps including 2 exons and 1 intron. The average GC content of the coding region is 58.77%, while the GC content of the third position of this gene is as high as 82.23%. Four Ca2+ binding sites (EF-hand) are found in this gene. The predicted molecular mass of the deduced peptide is 16688.72 Da and the pI is 4.222. By aligning with known CaM genes, the similarity of CaM gene sequence with homologous genes in Chlamydomonas incerta and Chlamydomonas reinhardtii is 72.7% and 72.2% respectively, and the similarity of the deduced amino acid sequence of CaM gene with homologous genes in C. incerta and C. reinhardtii are both 71.5%. This is the first report on CaM from a species of Rhodophyta.  相似文献   

10.
Polysiphonia urceolata is one type of potential commercial red seaweeds used for breeding and cultivation, because of its significant biochemical and biomedical application. However, the information of breeding and seedling incubation for cultivation is limited, especially the early development. In this study, tetrasporohyte and gametophyte of P. urceolata were taken as the study materials in Huiquan Bay, Qingdao, China. The cleaned and sterilized tetrasporophytes and gametophytes were pre-cultured in sterilized seawater, then nurtured at 18°C, 25 μmol photons m−2 s−1 in 12:12 h (light:dark) photoperiod. Continuous observation under microscope showed that the early development consists of bipolar division stage and seedling stage. In the division stage, tetraspores germinate into bipolar sporelings that further differentiate into a colorless rhizoidal portion and a lightly pigmented upright shoot. The lightly pigmented rhizoidal cell develops to a rhizoid and the larger pigmented cell transforms to an erect axis. In the seedling stage, several quasi-protuberances appear on the erect axis and form juvenile seedlings. The results demonstrate the culture of P. urceolata from tetraspores under laboratory conditions. Supported by National Key Technology Support Program, Development Program of China (No.2006AA09Z21), National Natural Science Foundation of China (No. 40618001 and N_CUHK438/06) and Shandong Agricultural Seed Stock Breeding Project  相似文献   

11.
Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination rate of eelgrass (Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45, increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA) (P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly increased the germination rate at salinity 5 (P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination rate at 14°C (P<0.001). Although significant interaction was found between temperature and salinity (P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results provide useful information for the propagation of artificial seedlings for seagrass restoration in China.  相似文献   

12.
Polychaete Neanthes japonica is a species geographically specific in China and Japan with important scientific implication and commercial value. In this study, the relations of body weight, salinity and temperature to oxygen consumption and ammonia excretion of N. japonica were determined. Three different groups in body weight (large: 2.34±0.36 g, middle: 1.50±0.21 g and small: 0.62±0.12 g) were set for all experiments. Results show that the body weight is negatively related to the rates of oxygen consumption and ammonia excretion; and the relationship is significant. The oxygen consumption and ammonia excretion at 24°C decreased at salinity from 5 to 30 and increased above 30, indicating that both lower and higher salinity are adverse and certain degree of salinity stress is necessary for enhancing the energy demand. At salinity 30, rising temperature from 18°C to 30°C, the oxygen consumption increased before 27°C and then decreased. However, the relation of ammonia excretion and temperature seems more complex. Two-way ANOVA shows that salinity, temperature and body weight all have a significant effect on the oxygen consumption and ammonia excretion of the worm. Moreover, interaction between salinity/temperature and body weight is also significant. O:N (oxygen/nitrogen) ratio varies greatly in this case from 5.97 to 463.22, indicating that N. japonica can regulate the type of metabolic substrate against environment changes. Supported by the National Natural Science Foundation of China (No. 30490233) and the Three-Gorge Project and the Estuarine Environment (No. SX2004-018) from the Three Gorges Project Construction Committee  相似文献   

13.
During a survey for marine microalgal resources, we isolated a rare marine euglenoid from the coastal waters of Qingdao, China in 2009, and established a pure culture. Electron microscopic and molecular phylogenetic (18S rDNA and 16S rDNA sequences) analyses revealed a close affinity with Eutreptiella gymnastica, a bloom-forming species. Different culture conditions were monitored to understand optimal E. gymnastica growth characteristics. The optimal growth conditions in a batch culture of this isolate were 20°C, 160 μmol photons/(m2×s) of white light, and a salinity of 10-31. Nutrient experiments demonstrated that growth increased dramatically with a phosphorus concentration greater than 72 μmol/L. Understanding the effect of culture conditions on E. gymnastica may help understanding the blooming mechanism of this alga in its natural environment.  相似文献   

14.
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32°C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24°C, 20 and 200 μmol/(m2·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30°C, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38°C, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively. Supported by the 908 Special Program (908-02-04-07), the National Basic Research Program of China (973 Program, No. 2006CB400608), and K. C. Wong Magna Fund in Ningbo University  相似文献   

15.
Members of the DnaJ family are proteins that play a pivotal role in various cellular processes, such as protein folding, protein transport and cellular responses to stress. In the present study, we identified and characterized the full-length DnaJ cDNA sequence from expressed sequence tags of Pyropia yezoensis (PyDnaJ) via rapid identification of cDNA ends. This cDNA encoded a protein of 429 amino acids, which shared high sequence similarity with other identified DnaJ proteins, such as a heat shock protein 40/DnaJ from Pyropia haitanensis. The relative mRNA expression level of PyDnaJ was investigated using real-time PCR to determine its specific expression during the algal life cycle and during desiccation. The relative mRNA expression level in sporophytes was higher than that in gametophytes and significantly increased during the whole desiccation process. These results indicate that PyDnaJ is an authentic member of the DnaJ family in plants and red algae and might play a pivotal role in mitigating damage to P. yezoensis during desiccation.  相似文献   

16.
Algae(and their extracts) are increasingly important for pharmaceutical applications due to the diversity of useful compounds they contain. The genus Fucus contains one of the most studied species,Fucus vesiculosus. The species F. ceranoides differs from the others of the genus by presenting longitudinal air-vesicles and a capacity to survive at low salinities. It is an alga that inhabits the Mondego River estuary(Portugal), at the southern limit of its distribution, and can serve as a role model to understand the effect of a salt gradient on the production of bioactive compounds. We assessed the phenolic content and antioxidant activity of different F. ceranoides extracts(e.g. methanolic, aqueous and polysaccharide) prepared from samples harvested from two different zones to evaluate if the adaptation of F. ceranoides to different salinity levels influenced its chemical composition. The antioxidant activity of the extracts was determined using 1,2-diphenyl-picrylhydrazyl(DPPH) and 2.2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)radicals. These assays demonstrated that the methanolic extract of lyophilized F. ceranoides that grew at low salinities was the most bioactive, i.e. DPPH(IC_(50)=50.39 μg/mL) and ABTS(TEAC=2.42). The total phenolic content(Folin-Ciocalteu method) and the methanolic extract of the lyophilized F. ceranoides collected from a low salinity habitat exhibited the highest phenolic content(PGE=49.48 μg/mg of lyophilized extract)amongst those sampled. Thin layer chromatography(TLC) and Fourier transform infrared spectroscopy(FTIR) were used for the identification of compounds in the extracts. This characterization allowed confirmation that the various extracts contained almost the same compounds but with notable quantitative differences. Based on these results, we conclude that there were differences in the quantity of the compounds due to the effect of salinity. The drying methods used were also found to have influenced the quality of the extracted compounds.  相似文献   

17.
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   

18.
Effects of temperatures and salinities on oxygen consumption and ammonia-N excretion rate of clamMeretrix meretrix were studied in laboratory from Oct. 2003 to Jan. 2004. Two schemes were designed in incremented temperature at 10, 15, 20, 25°C at 31.5 salinity and in incremented salinity at 16.0, 21.0, 26.0, 31.5, 36.0, and 41.0 at 20°C, all for 8–10 days. From 10 to 25°C, both respiration and excretion rate were increased. One-way ANOVA analysis demonstrated significant difference (P<0.01) in physiological parameters in this temperature range except between 15 and 20°C. The highestQ 10 thermal coefficient value (12.27) was acquired between 10 and 15°C, and about 1 between 15 and 20°C, indicatingM. meretrix could well acclimate to temperature changes in this range. Salinity also had significant effects on respiration and excretion rate (P<0.05). The highest values of respiration and excretion rate ofM. meretrix were recorded at 16.0 salinity (20°C). These two physiological parameters decreased as salinity increased until reached the minimumQ 10 value at 31.5 (20°C), then again, these parameters increased with increasing salinity from 31.5 to 41.0.M. meretrix can catabolize body protein to cope with osmotic pressure stress when environmental salinity is away from its optimal range. No significant difference was observed between 26.0 and 36.0 in salinity (P>0.05), suggesting that a best metabolic salinity range for this species is between 26.0 and 36.0. This work is supported by National High-Tech R & D Program of China. (863 Program) (2002AA603014).  相似文献   

19.
Laminaria gametophyte was greatly influenced by light in its growth and development. Using light-emitting diodes (LED) as blue and red light sources, we analyzed the light effect on gametophytes development ofLaminaria japonica Aresch. The gametophytes were obtained from zoospores collected in April, May, July, 2003 and September, 2004. We found that the growth of gametophytes was stimulated by increasing intensity of blue light (BL) and red light (RL) illumination, of which BL was obviously stronger than that of RL. The fertilization of gametophytes depended largely on BL, and only sufficient BL illumination could take the reproductive effect. In addition, we noticed that there was a significant difference in light responses for gametophytes developed from zoospore collected in different times. For zoospores released in April, under BL1 (73.90 μmol photons/m·s), the unicellular female gametophytes and multi-cellular male gametophytes produced eggs and sperms respectively, and further developed towards sporophytes. However, for gametophytes developed in May, July or September, they became multi-cellular and never formed oogonia or antheridia. It is believed that theLaminaria sporangium maturation stage could affect the gametophytes reaction to BL under laboratory culture conditions. Therefore, cryptochrome- or phototropin-like BL photoreceptors is probably involved in BL-induced development ofLaminaria gametophytes. This research was supported by the NSFC (No.40376049) and Japan Society for the Promotion of Science (The Invitation Fellowship for Research in Japan 2002).  相似文献   

20.
From 1997 to 2000, four field surveys were conducted in the East China Sea (ECS) (23°30′–33°00′N, 118°30′–128°00′E). A field data yield density model was used to determine the optimal salinities for 19 dominant copepod species to establish the relationship between surface salinities and abundance of those species. In addition, ecological groups of the copepods were classified based on optimal salinity and geographical distribution. The results indicate that the yield density model is suitable for determining the relationship between salinity and abundance. Cosmocalanus darwini, Euchaeta rimana, Pleuromamma gracilis, Rhincalanus cornutus, Scolecithrix danae and Pareucalanus attenuatus were determined as oceanic species, with optimal salinities of >34.0. They were stenohaline and mainly distributed in waters influenced by the Kuroshio or Taiwan warm current. Temora discaudata, T. stylifera and Canthocalanus pauper were nearshore species with optimal salinities of <33.0 and most abundant in coastal waters. The remaining 10 species, including Undinula vulgaris and Subeucalanus subcrassus, were offshore species, with optimal salinity ranging from 33.0–34.0. They were widely distributed in nearshore, offshore and oceanic waters but mainly in the mixed water of the ECS.  相似文献   

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