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1.
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   

2.
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   

3.
IAA 3-Indolylacetic acid, NAA a-Naphthylacetic acid and cytokinins in PESI culture medium were used in a study on the effects of plant hormones on the growth of free-living conchocelis ofPorphyra yezoensis which showed that its growth in medium with cytokinins, IAA and NAA was more rapid than that in medium with non—phytohormones; that the optimal concentrations for promoting growth were 10 μg/L for IAA and ZA (Zeatin), and 0.1 μg/L for BA 6-Benzyl amino purine and KIN 6-Furfurylamino- purine. Mix use of NAA, IAA and cytokinins, NAA/ZA 1–1000/1 μg/L, NAA/BA 10/1-1000 μg/L, NAA/KIN 1/1-1000 μg/L promoted growth. IAA/ZA 0.1-1/0.1-1 μg/L; IAA/BA 0.1-1/0.1-10 μg/L IAA/KIN 1/0.1-1000 μg/L also promoted growth. Contribution No. 2335 from the Institute of Oceanology, Chinese Academy of Sciences. Contribution No. 94 from the Experimental Marine Biology Lab Qingdao, China. The research was supported by a grant from the Chinese Academy of Sciences.  相似文献   

4.
Experiments on salimity tolerance of embryos and larvae of the southern bay scallopArgopecten irradians concentricus Say under controlled temperature of 28°C showed that although the eggs were fertilized and cleaved at salinity 18.1–37.4, they could further develop into normal D-shaped larvae only at salinity 23.4–36.1, while the trochophore larvae could develop into normal D—shaped larvae at salinity 22.1–39.9. For 72 hours, the larvae could tolerate salinity of 18.4–43.9, the salinity favoring growth was 19.8–42.4; the suitable range was 21–36, and the optimum at about 28. They metamorphosed at salinity 18.9–43.5, optimally at 24–32. Contribution No. 3301 from the Institute of Oceanology, Chinese Academy of Sciences. The research was supported by the National Climbing Project B(PDB6-3-2).  相似文献   

5.
Heat shocks effectively produced triploids inPenaeus chinensis. Fertilized eggs heat shocked (28–32°C) for 8 to 16 minutes, starting from 8 to 20 minutes after spawning, resulted in triploidy induction rates of 39%–75%. Several triploid populations were cultured to 10 cm. In a triploid population, two kinds of ovaries were observed. Histological examination showed apparent differences between these two kinds of ovaries, whereas among male shrimp, there were no such differences. Contribution No. 3465 from the Institute of Oceanology. Chinese Academy of Sciences. The study was supported by the International Foundation for Science, Asian Fisheries Society and Chinese Climbing Project PDB 6–2, and Chinese National 863 Project (No. 863-819-01-05).  相似文献   

6.
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   

7.
INTRODUCTIONTheJapaneseseabass (LateolabraxjaponicusC&V)distributeswidelyinthecoastalwatersalongtheBohaiSea ,YellowSea ,EastChinaSea,andSouthChinaSea .Asacarnivorousfish ,itoccupiesthehightrophiclevelinthemarineecosystemandhasadaptedtovariousenvironmentalr…  相似文献   

8.
This research on the influence of sediment resuspension on the flux of materials in the margin of the East China Sea showed that the sediment resuspension rates, was 47.40%–79.18% in the surface layers, and 72.75%–96.96% in the bottom layers. The research confirmed that the Changjiang River runoff and the eddy area upwelling flow near 125°E were two important factors affecting the sediment resuspension in summer; the transformation of DOC to POC through the flocculation in the transitional region (123°–124°E) was also confirmed by comparison of the resuspension rate. The sediment resuspension was shown to be influenced by the seasonal factor, especially in the surface layer. Contribution No. 4017 from the Institute of Oceanology, Chinese Academy of Sciences. Project 49636210 supported by NSFC.  相似文献   

9.
INTRODUCTIONTheseasurfacemicrolayer (SM)withspecialphysical,chemicalandbiologicalproperties,hadbeenwelldescribedasasiteofintensiveaccumulationofdissolvedandparticulateorganicmat terinvolvingphytoplanktonandbacteria (Hardy,1 982 ) .Thisenvironmenthasgreatimpor…  相似文献   

10.
The present study investigated the possible changes in the mixis potential of rotifer resting eggs produced by a single stock of Brachionus plicatilis and collected and preserved annually from 1985 - 1998. Several clones derived from each batch of resting eggs were cultured under the same conditions for 21 days. The percentage of clones appearing resting eggs and the average yield of resting eggs produced from each clone were recorded and statistically analyzed to find the differences between the mixis potential of those resting egg batches. Results showed that different batches of resting eggs had different mictic levels among their descendent clones; but no regular relationship was found between the mixis potential of resting eggs and their collection times/preservation periods. Several internal and external factors that might affect the mixis potential of resting eggs were discussed.  相似文献   

11.
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   

12.
Refraction seismic data obtained from a sonobuoy (SB7) in the East China Sea shelf marginal ridge was processed and interpreted. Intercept times and layer velocities were used to set up a one-dimension depth-velocity model based on which a two-dimenssion depth-velocity crustal model was established through two-dimension ray-tracing. The computation results showed that the upper crustal depth-velocity model beneath lineSB7 is composed of four layers with primary wave velocities of 1.80–2.20, 2.85–2.90, 3.24–3.34 and 4.55–6.00 m/s respectively. Neighbouring reflection seismic data and data on the East China Sea (ECS) regional geology were used to study the relationship between the velocities and their formation ages and also the contact relationship between the velocity boundaries. Contribution No. 3259, from the Institute of Oceanology, Chinese Academy of Sciences. Project 49376266 supported by NSFC.  相似文献   

13.
The spermatozoon ultrastrucmre of left-eye flounder, Paralichthys olivaceus, was ob-served by electronic microscopy, and shown to consist of head, midpiece and tail. Some nuclear vacuoles were observed inside and along the outer part of the nucleus and double-membrane structures were ob-served between the nuclear membrane and plasma membrane. The sperm sleeve consisted of four indepen-dent parts and had more than four mitochondria. Along the sperm tail there were wing-like lateral tins.  相似文献   

14.
The meiotic process in Noctiluca scintillans were observed under light microscope.Some abnormal cell divisions, incompletely separated “zoospores” and the changes of the zoospores are described in this paper. Together with the fmdings of field samplings and the previous results by other researchers, the process of meiosis in N. scintillans was supposed to be a pathway to reduce the extra high density of NH3-N within the cell in order to ensure normal population growth.  相似文献   

15.
The present paper reports 7 species of pontoniine shrimps collected from Hainan Island,South China Sea,by the Joint Chinese-German Marine Biology Expeditions,in which,Conchodytes nipponensis(De Haan,1844)and Coralliocaris brevirostris Borradaile,1898 are new records from Chinese waters.  相似文献   

16.
After discarding marine microorganisms from conchocelis of Porphyra yezoensis and Porphyra ha/tanens/s, their axenic cultures were obtained through treatment with antibiotics. Antibiotic disc tests were carried out to determine the effectiveness of each antibiotic in eliminating contaminating microorganisms. Five of 12 antibiotics tested were selected and used to produce the axenic cultures in this study, which showed that 200 μg/mL streptomycin, 250 μg/mL penicillin, 252 μg/mL kanamycin, 30 μg/mL neomycin, 200 μg/mL chloramphenicol were effective concentrations for eliminating microorganisms from conchocelis when antibiotics were added singly step by step; whereas simultaneous combination of 150 μg/mL streptomycin, 250 (or 350) μg/mL penicillin, 150 (or 250) μg/mL kanamycin, 70 μg/mL neomycin and 200 μg/mL chloramphenicol was also effective for producing the axenic cultures. However,it seemed that the treatments with antibiotics applied individually were more feasible than those with all antibiotics added at the same time. This may be due to the combined inhibiting effect of antibiotics on the growth and development of conchocelis.  相似文献   

17.
Results of neutron activation analysis (NAA) ofSargassum thumbergii samples collected from the Qingdao Taipingjiao coast on March 20, 1996 showed that (1)Sargassum thunbergii can to some extent accumulate potassium and calcium (the accumulation coefficient was 10); (2) it can accumulate almost all trace elements, especially iron, managanese and zinc; (3) it can accumulate strontium, aluminium thorium, and rare earth elements. Contribution No.3308 from the Institute of Oceanology, Chinese Academy of Sciences. The study supported by the National Ninth-Five-Year Key Project “96-916-04-01”.  相似文献   

18.
Graded levels of manganese were supplemented to a semi-purified diet containing 45% crude protein, to provide six levels of manganese (i. e. containing 5, 25, 50, 70, 140 and 210×10−6, respectively) for two experiments with these experimental diets. The initial weight of shrimp used in the 35–day experiment I was 0.30±0.04 g, and that in the 70–day Experiment II was more than one gram. The results showed that optimum content in the semi-purified diet for the more than 1 gram shrimp ranged from 70 ×10−6, to 140×10−6, but supplementation of Mn was not necessary for the small shrimp. Contribution No. 2673 from the Institute of Oceanology, Chinese Academy of Sciences.  相似文献   

19.
A combined numerical model of wind, wave, tide, and storm surges was built on the basis of the “wind field model in limited sea surface areas”. When used to forecast the sea surface wind, wave height and water level, it can describe them very well. Contribution No. 4108 from the Institute of Oceanology, Chinese Academy of Sciences. This work supported by Stress Project (KZ952-S1-420), Chinese Academy of Sciences; 863 Project (863-818-06-05), and (863-818-Q-07)  相似文献   

20.
Scrippsiella trochoidea (Stein) Loeblich III was grown in a nitrogen-or phosphorus-limited batch culture system in laboratory. Growth rates and cellular Chl-a were measured as functions of nitrate and phosphate concentrations. Growth rates were hyperbolic with both nitrate and phosphate concentration and fit the Monod equation. The minimum cell quota of nitrogen and phosphorus and then the optimum N∶P ratio ofS. trochoidea were estimated in this study. Measurement of phosphate concentration in Jiaozhou Bay suggest that phosphorus is the limiting factor ofS. trochoidea growth. Contribution No. 3679 from the Institute of Oceanology, Chinese Academy of Sciences. Project 39790110 supported by NSFC, the study aslo supported by the National Climbing Project B (PDBG-7-2) and partly supported by an MF grant from Hong Kong University of Science and Technology.  相似文献   

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