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1.
mODUcrIONDuringaninvestigationofthehtrithcorTunnitiesofFishinthehighlandlakesinYunnanProvinceofChina,aastodewasfoundintheintchtinesofafish,SinocycIocheiIusgrahamitingiFangwhichoccursonlyinFuxianLake(Chuetal.,l989),oneofthesevenlakesstudied.ThecharaCteristiesoftheastodespdriobtainedassignsthemdearlytothegenusProt~alus.FurtherexathenationstalustoconsiderthisastodeasanewspedesinthegenusProteOCotalus.Thisnewspedisdescritalinthispaper.MareRIusroMErnOosFuxianLake,theserenddeepestlakeinC…  相似文献   

2.
The morphology of larval and 1st postlarval stages ofPenaeus penicillatus are described. Results from comparative studies on larval development ofP. penicillatus, P. merguiensis andP. chinensis are as follows: These three species could not be identified during their naupliar stages. In the 1st protozoea, the antennule L1/L2 value is 1.7–2.0 inP. merguiensis, but less than 1.7 inP. chinensis andP. penicillatus; in the 2nd protozoea, the supra-orbital spine inP. chinensis is not bifurcated, while those ofP. merguiensis andP. penicillatus are bifurcated; in the 3rd protozoea, there is a minute (or no) dorso-median spine on the posterior margin of the 1st and 2nd abdominal somite inP. chinensis, but they are prominent inP. merguiensis andP. penicillatus. In the mysis and 1st postlarval stages,P. chinensis differs fromP. merguiensis andP. penicillatus in having 9 (8 in the other 2 species) long setae on the exopod of pereopods 1–3; additionally, one dorsal tooth appears on the rostrum ofP. chinensis in the 2nd mysis and that of the other 2 species in the 3rd mysis;P. chinensis has 2 (mostly) or 1 dorsal tooth on the rostrum in the 3rd mysis and 2–3 in the 1st postlarva, whileP. penicillatus andP. merguiensis have only 1 in the 3rd mysis and 1st postlarva. Comparative studies on larval development showedP. penicillatus has closer affinity withP. merguiensis than withP. chinensis. Contribution No. 2218 from the Institute of Oceanology, Chinese Academy of Sciences  相似文献   

3.
Results of the experiment of northward transplantation ofPorphyra haitanensis showed that intercrop ofP. haitanensis with Bay Scallop is feasible because the growth duration of both of them is about the same in August–December. Full use of cultivating area, lowering its cost and increasing its product per unit area as well as improving the ecological environment are realized during intercrop. Contribution No. 2152 from the Institute of Oceanology, Academia Sinica.  相似文献   

4.
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   

5.
Specimens ofNemertopsis gracilis var.bullocki Coe, 1940 collected from Huian, Fujian Province, China, are described. The variety is upgraded to specific level on the basis of: the dorsal surface having a pair of blackish brown longitudinal stripes meeting anteriorly with a broad transverse band of the same color; the proboscis having 11–13 distinct proboscis nerves in its longitudinal muscle layer. Project 39170111 and 39470097 supported by NSFC.  相似文献   

6.
The early effects of chromosomal manipulation of eggs and sperm on the yields of trip-loid and gynogenefic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fen.ilized eggs at 0 - 2℃ for 45 minutes duration 5 minutes after fen.ilization, and the in-duced triploidy rates were 31.2% - 50% and the relative hatching rates were 53.3% - 99%. Gynnge-aetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 -2℃ for 45 minutes duration 5 minutes after fertihzation. The induced gynogenetic diploid rates and the relative hatching rates were 94 % - 96 % and 48.5 % - 68.5 % respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae ac-cording to Student‘s t-test (α = 0.05). The relationship between the early growth of the triploid experi-mental group larvae and that of gynogenetic diploid experimental group larvae was also studied.  相似文献   

7.
This paper deals with the proportional distribution, niche breadth and niche overlap of two metazoan parasites (copepods species,Ergasilus anchoratus Markewitsch, 1946 andPseudergasilus parasiluri Yamaguti, 1936) and monogeneans (in the genusSilurodiscoides Gussev, 1976) found on gills of the fish,Silurus asotus L. from Jiangkou Reservoir in Jiangxi Province, China.E. anchoratus was the common and dominant metazoan parasite on gills of the fish in this locality as indicated by the higher infection levels, and distributed almost evenly on gill arches without any observed gill-arch preference, as shown by the wide proportional distribution and broad niche breadth.P. parasiluri and monogeneans inSilurodiscoides were found also without any significant gill-arch preference although they had a rather narrow niche breadth. The observed significant overlap betweenP. parasiluri andSilurodiscoides spp. may be simply due to the lower infection levels of the parasites. The observed pattern of unrestricted distributions of the parasitic copepods on gills of the fish may be accounted for, at least in part, by the moving ability of the copepods, and may also indicate that the parasite does not exhibit any feature of gill-arch preference. However, further experimental research is needed to verify the microhabitat distribution of the parasites. Project 39370122 supported by NSFC.  相似文献   

8.
As seedling culture is a crucial factor for successful cultivation ofGelidium, the authors researched tissue culture technology for producing seedlings. The morphogeny and experimental ecology were observed and studied fully in 2–5 mm isolated tissue fragments. Regeneration, appearance of branching creepers and attaching structure and new erect seedlings production and development were studied. Fragments were sown on bamboo slice and vinylon rope. The seedlings were cultured 20–30 days indoor, then cultured in the sea, where the density of erect seedlings was 3–19 seedlings/cm2, growth rate was 3.84% day. The frond arising from seedlings directly was up to 10 cm per year. The ecological conditions for regenerated seedlings are similar to the natural ones. The regenerated seedlings are suitable for raft culture in various sea areas.  相似文献   

9.
The structural feature of agar polysaccharides fromPorphyra haitanensis grown in south China and transplanted to the north was investigated by fractionation on DEAE—Sephadex A 50, chemical analysis, and infrared and13C-NMR spectroscopy. The agars composed mainly of charged molecules were eluted from DEAE—Sephadex A 50 with 1.0 mol/L NaCl solution from the southernP. haitanensis and with 0.5 mol/L NaCl from the northern one. The13C-NMR spectra showed that agarobiose [(1→3)-β-D-galactopyranosyl-(1→4)-3,6-anhydro-α-L-galactopyranose] and the biological precursor of agarobiose [(1→3)-β-D-galactopyra nosyl-(1→4)-6-sulfate-α-L-galactopyranose] were the major disaccharide repeating units in the charged fractions. The content of the biological precursor in the agar polysaccharides from southernP. haitanensis was higher than that in the northern one, the content of the biological precursor extracted from cold water was higher than that from hot water, and the content of 6-OMe-D-galactose in the southernP. haitanensis polysaccharides was higher than in the northern one. This distinct difference will be of significance for further study of the physiological characters ofP. haitanensis. Contribution No. 1849 from the Institute of Oceanology, Academia Sinica.  相似文献   

10.
The living morphology and infraciliature of two rare marine ciliates, Placus salinus Dietz, 1964 and Strombidium apolatum Wilbert and Song, 2005, collected from the coastal waters near Qingdao, China, were investigated by in vivo observation and protargol impregnation technique. The improved diagnosis for Placus salinus is as follows: medium-sized marine Placus, in vivo (50–60)μm×(30–40)μm; cell elliptical to barrel-shaped; 28–31 somatic kineties; single macronucleus usually ellipsoid and one micronucleus located in the indention of the macronucleus; one contractile vacuole posteriorly positioned. Strombidium apolatum is characterized by: marine strombidium (40–60)μm×(30–45)μmm in vivo, cordiform in shape with somewhat pointed posterior end and conspicuous apical protrusion; extrusomes prominent, about 15μm in length and evenly arranged along the circle kinety; about 16 collar and 5–6 buccal membranelles; one elongate macronucleus and one micronucleus; circle and ventral kineties consisting of about 53 and 45 dikinetids respectively.  相似文献   

11.
Two new species of the genusTinocladia Kylin (1940)T. eudesmoides Ding et Lu sp. nov. andTinocladia zhangii Ding et Lu sp. nov., are described.T. eudesmoides is mainly characterized by its longitudinally and transversely produced sub-cortical filaments from the medulla, its short uniseriate assimilating filaments, usually composed of 6–10 cells with slightly swollen and narrow ultimate cells, and its unilocular sporangia (60–115)×55–70μm, variable in size.T. zhangii is mainly characterized by its very solid frond, not rip apart by hands, its evident longer primary branches, its short and slender secondary branches, with very evident sub-cortical layer, and filaments divided repeatedly, and its large and small unilocular sporangia, with the latter borne on an evidently swollen pedicel. Project B80981816 supported by the NSFC. Contribution No. 4443 from the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.  相似文献   

12.
This paper reports the approprite ranges of Mg^2 ,Ca^2 and their ratio Mg^2 /Ca^2 in mixed seawater for rearing of Penaeus japonicus larvae,The ranges for the above three indices are 1150-1450mg/L,360-440mg/L and 2.8-3.4,respectively,the proper salinity range of mixed seawater is 22.1-33.9 obtained by mixing estuarine water and concentrated seawater.  相似文献   

13.
Thirty-two 63.0–134.4 mm standard length specimens collected during 1954–1990 from the coastal waters of the South China Sea and the continental coast of the Taiwan Strait were identified as a new species,Pampus minor Liuet Li, sp. nov. Contribution No. 3329 from the Institute of Oceanology, Chinese Academy of Sciences. Study supported by Chinese Academy of Sciences Special Grant for Biota Research.  相似文献   

14.
Randomly amplified polymorphic DNA (RAPD) technique was applied to assess the genetic variations and phylogenetic relationships in 4 species ofPorphyra. The samples were collected from the coast of Canada, Vietnam, Zhoushan, Fujian and Qingdao in China. Amplifications with 20 primers were carried out under predetermined optimal reaction conditions (samples were first heated at 94°C for 5 min. and followed by 45 cycles of 1 min at 94°C, 1 min at 36°C, and 2 min at 72°C, then held at 72°C for 10 min). The amplified products were scored as present (1) or absent (0) for each DNA sample and an index of genetic similarity (F) was calculated by using Nei & Li’s matching coefficient method (1979). The value of (1−F) was used to quantify the genetic distances between species and construct a phylogenetic tree. The relationship indicated by the UPGMA and NJ cluster analysis on the values of the genetic distance is in good overall agreement with classical taxonomy. The obvious differences between natural and cultivated population ofP. haitanensi suggest that variation or hybridization with other species occurred during the culture. Contribution No. 100 from the Experimental Marine Biology Laboratory, IOCAS. Contribution No. 3289 from the Institute of Oceanology, Chinese Academy of Sciences. The research supported by the Foundation of the Chinese Academy of Sciences.  相似文献   

15.
A fragment of a large sub-unit ribosomal DNA (LrDNA) of 12 strains ofProrocentrum species was amplified by polymerase chain reaction (PCR). The PCR products were digested by 3 restriction endonucleases (Cfo I, Hae III, and RSA I) and then resolved in agarose gels. Results show that different species had different RFLP patterns, except forP. arcuatum (ME 131), which had the same pattern toP. micans (ME160 and 04). The same fragment of 19 strains of the genus was also amplified and subjected to denaturing gradient gel electrophoresis (DGGE). 11 different patterns were resolved. Different cultures of a same species had the same pattern. The results of RFLP and DGGE analyses showed that eight newly isolated epibenthicProrocentrum species were different from each other, and also from other cultured ones examined in this study.P arcuatum (ME132) could not be differentiated fromP. micans (ME160 and 04), it was probably mis-identified, since they are quite different morphologically.P. redfieldii (ME138) could also not be distinguished formP. triestinium (ME132), it should be regarded as a synonym ofP. triestinium. Unexpectedly, a restriction site was found inP. micans, compared with previous sequence data. Project supported by National Basic Research Priorities Program (2001CB409701, 2001CB409710) and supported by NSFC (40376040, 40025614)  相似文献   

16.
Inorganic carbon utilization in the non-calcifying marine microalgae,Nannochloropsis oculata, Phaeodactylum tricornutum andPorphyridium purpureum was compared with high- and low-calcifying strains ofEmiliania huxleyi grown in artificial seawater medium aerated with either air (0.03% V/V CO2) or CO2-free air. For high-calcifying strain ofE. oculata andP. tricornutem, similar growth patterns were observed in air-and CO2-free air-grown cultures.P. purpureum showed a less final cell density in CO2-free air than in air-grown culture. However, low-calcifying strain ofE. huxleyi was able to grow only in air-grown culture, but not in CO2-free air-grown culture. Measurements of alkalinity, pH, concentration of dissolved inorganic carbon (DIC) and free CO2 showed different patterns of DIC utilization. WithN. oculata, P. tricornutum andP. purpureum the pattern of DIC utilization was characterized by an increase of pH and a decrease of DIC but a constant alkalinity in the cultures aerated with air or CO2-free air, suggesting that bicarbonate utilization was concomitant with an efflux of OH. Both alkalinity and pH were maintained rather constant in air-grown culture of low-calcifying strain ofE. huxleyi, suggesting that diffusive entry of CO2 could meet the requirement of DIC for its photosynthesis and growth. High-calcifying strain ofE. huxleyi, however, showed a pattern of decrease of alkalinity and DIC but an almost constant pH, indicating that bicarbonate was the major form of inorganic carbon utilised by this organism and bicarbonate uptake is unlikely to be accompanied by an efflux of OH. The final pH values reached byN. oculata, P. tricornutum andP. purpureum in a closed system were 10.75, 10.60 and 9.85 respectively, showing that bicarbonate utilisation is concomitant with an efflux of OH. While the final pH of 8.4 in high-calcifyingE. huxleyi suggests that bicarbonate utilization was not accompanied by an efflux of OH. Contribution No. 3557 from the Institue of Oceanology, Chinese Academy of Sciences. This work was supported by NERC grant GRE3/7853 U. K. and partly supported by Bio-Engineering Center, SSTC 96-C01-05-01.  相似文献   

17.
The rates of photosynthesis and respiration ofPorphyra, Laminaria andUndaria were determined with an oxygenmeter at different temperatures in an enclosed continuous-flow system. The temperature coefficients of respiration and the net primary productivities for the three species were calculated. The spectacular rates of primary production were found to be as high as 270 g C m−2 forP. yezoensis, 2200 g C m−2 forL. japonica and 160 g C m−2 forU. pinnatifida annually. The low respiratory rates of these three species as well as low light compensation points especially at low temperatures are considered as a reason to save heat energy, resulting in a high productivity, especially in case ofLaminaria. Contribution No. 945 from the Institute of Oceanology, Academia Sinica. The paper was presented at the International Phycological Society Meeting, 19–22 Aug. 1980, Glasgow, UK.  相似文献   

18.
19.
Laboratory culture experiments showed that <100μ mol/L nitrate, amonium or mixture of amino acids promote the growth of the red tide organismProrocentrum micans Ehrenb, but that >100μmol/L of ammonium, or mixture of glycine and glutamate was harmful to growth, and that orthophosphate wasP. micans’ main phosphorous source in the ocean. Presence of 80μ mol/L EDTA, 0.5 to 1 μmol/L Fe3+, 1.0 to 20.0 μ mol/L Mn2+ 0.1 to 0.4 μmol/L Co2+ in the culture medium could improve the growth ofP. micans. Vitamin B1 promoted growth, but vitamin B12 and biotin did not. The estimated minimum cell quotas (q o) for nitrogen and phosphorus being 0.74 pmole/cell and 0.045 pmole/cell show that phosphorus (more than nitrogen) limits the growth ofP. micans in the study area. This project was supported by the Natural Science Foundation of Zhejiang Province.  相似文献   

20.
Length-frequency data of eight commercial fish species in the Beibu Gulf (Golf of Tonkin), northern South China Sea, were collected during 2006-2007. Length-weight relationships and growth and mortality parameters were analyzed using FiSAT II software. Five species had isometric growth, two species had negative allometric growth, and one species had positive allometric growth. Overall, the exploitation rates of the eight species were lower in 2006-2007 than in 1997-1999: for four species (Saurida tumbil, Saurida undosquamis, Argyrosomus macrocephalus, and Nemipterus virgatus) it was lower in 2006-2007 than in 1997-1999, for two species (Parargyrops edita and Trichiurus haumela) it remained the same, and for the other two species (Trachurus japonicus and Decapterus maruadsi) it was higher in 2006-2007 than in 1997-1999. The exploitation rates might have declined because of the decline in fishing intensity caused by high crude oil prices. The optimum exploitation rate, estimated using Beverton-Holt dynamic pool models, indicated that although fishes in the Beibu Gulf could sustain high exploitation rates, the under-size fishes at first capture resulted in low yields. To increase the yield per recruitment, it is more effective to increase the size at first capture than to control fishing effort.  相似文献   

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