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1.
《中国海洋大学学报(自然科学版)》2021,(Z1)
以三倍体长牡蛎(Crassostrea gigas)"海大1号"为材料,从诱导强度、诱导时机和诱导持续时间三个方面比较了6-DMAP与盐度诱导"海大1号"长牡蛎四倍体的效果,并对获得的四倍体幼虫群进行培育,探讨了"海大1号"长牡蛎四倍体幼虫群的生长、存活情况。研究表明,温度25℃、盐度30、诱导密度5×10~6个/mL的条件下,用浓度450μmol/L的6-DMAP在30%～40%的受精卵排放极体时诱导,持续诱导15 min,四倍体诱导效果最佳;四倍体率、孵化率和诱导效率分别达45.13%±1.44%,20.01%±1.37%和9.03%。盐度诱导实验中,温度25℃、诱导密度5×10~6个/mL的条件下,用盐度12的低盐海水在受精卵刚排放极体时诱导,持续诱导15 min,四倍体诱导效果最佳;四倍体率,孵化率和诱导效率分别达35.12%±2.24%、19.19%±1.12%和6.74%。长牡蛎"海大1号"四倍体幼虫群的存活率极低,培育23 d后的存活率只有1.80%,最终成功培育出四倍体幼贝4 200粒。综合来看,6-DMAP和不同盐度诱导海大1号长牡蛎四倍体的最佳组合分别是:用450μmol/L的6-DMAP在极体排放30%～40%时持续诱导15 min;用盐度12的海水在极体刚排放时持续诱导15 min。 相似文献
2.
香港巨牡蛎♀×太平洋牡蛎♂异源三倍体的初步研究 总被引：1，自引：0，他引：1
本文以香港巨牡蛎(Crassostrea hongkongensis)和太平洋牡蛎(C.gigas)为研究对象,进行牡蛎异源三倍体研究试验。在水温25℃条件下,香港巨牡蛎剥离卵子于海水中浸泡促熟1.5h后,与太平洋牡蛎精子受精,获得最高卵裂率为(24.40±3.79)%。受精后20min,采用盐度为10的低渗海水处理杂交受精卵25min,可获得68.65%的异源三倍体幼虫,孵化率为12.71%。异源三倍体幼虫的存活率和生长率均未表现出优势。受精后第9天,异源三倍体幼虫的存活率仅为(0.116±0.023)%,平均壳长为(103.50±0.85)(m;对照组的存活率和壳长分别为(42.17±2.74)%和(123.25±8.60)μm。幼虫在附着变态前死亡。 相似文献
3.
2004年7~8月,利用诱导的1龄四倍体太平洋牡蛎做亲本,通过解剖取卵、人工受精的方法进行四倍体的自群繁殖。结果表明四倍体太平洋牡蛎自群繁殖的受精率为95.54%,孵化率为37.38%,采用同一雌体四倍体牡蛎与二倍体雄贝杂交产生的三倍体组(TD)的受精率为85.19%,孵化率为99.9%,而以二倍体做母本、四倍体做父本的杂交组(DT)的受精率为98.73%,孵化率为87.63%,二倍体对照组的受精率为96.39%,孵化率为99.9%。四倍体牡蛎经自群繁殖培育出稚贝1130粒。经流式细胞仪分析,四倍体太平洋牡蛎幼虫和稚贝的四倍体率均达到100%。幼虫培育过程中,从孵化出D-形幼虫到出现眼点,幼虫的成活率达11.86%,眼点幼虫的变态率高达16.1%。实验证明四倍体太平洋牡蛎可以进行自群繁殖,比诱导的方法简单高效。 相似文献
4.
太平洋牡蛎三倍体与二倍体特殊动力代谢的比较 总被引：4，自引：3，他引：4
采用耗氧强度测定法 ,对太平洋牡蛎三倍体和二倍体代谢进行比较研究。结果表明 ,在不同温度下 ,2n标准代谢 (StM)占常规代谢 (有饵料条件下 ,RfM)的比例平均为 85 7%( 82 6%— 91 % ) ,高于 3n的 78 4% ( 72 %— 84 3% ) ;2n因摄食所耗机械代谢变动于RfM的2 6%— 6 7% ,平均值为 4 3% ,低于 3n的 8% ( 4 9%— 1 3 6% ) ;同时 ,2n用于消化、吸收食物的代谢平均约占RfM的 9 98% ,低于 3n的均值 1 2 6%。经协方差分析检验 ,倍性对标准代谢、消化和吸收代谢及摄食代谢虽未表现出显著作用 ,但在不同生理状况下 ,2n耗氧率的均值都高于 3n。在 2 0℃下 ,对太平洋牡蛎 2n和 3n标准代谢和常规代谢 (无饵料条件下 ,RM)的昼夜周期性比较表明 ,3n的特殊动力代谢 (SDA)峰值略高于 2n,SDA持续时间和总耗能分别为 2n的 1 3倍和 0 80倍。实验还表明 ,2n和 3n在停食后 2 8h和 2 4h分别达到其排氨率的高峰 ,两者的排氨率差异虽不显著 ,但排氨率均值 3n高于 2n。 相似文献
5.
太平洋牡蛎多倍体研究 总被引：6，自引：0，他引：6
本文综述了太平洋牡蛎多倍体产生的途径、诱导方法、诱导结果、诱导机制、倍性鉴别方法、繁殖、生长、生理指标、抗逆性和口味等。提出：６－ＤＭＡＰ诱导牡蛎三倍体的技术前景广阔;四倍体与二倍体杂交的方法是产生三倍体的最好途径;四倍体是生物方法产生三倍体的中间材料,可以存活,应加大力度地研究和开发;三倍体的性腺能够发育,并可产生具有繁殖力的配子;在良好的环境里,四倍体的生长和抗逆性较二倍体优势;在繁殖季节,三 相似文献
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7.
利用四倍体与二倍体杂交规模化培育全三倍体太平洋牡蛎苗种 总被引：6，自引：0，他引：6
利用引进美国的四倍体太平洋牡蛎(Crassostrea gigas)雄贝与我国的二倍体雌贝杂交，规模化培育全三倍体牡蛎苗种。杂交组的平均受精率为48．27％，对照组为80．53％，杂交组较低的受精率可能与四倍体雄贝的精子活力及精子数量有关。杂交组的孵化率、幼虫成活率和变态率分别为81．10％，42．3％和1．82％，对照组分别为79．96％，37．0％和1.80％。杂交组共培育出稚贝1200万粒。不同时期取样的流式细胞仪分析结果表明，杂交组的三倍体率为100％。 相似文献
8.
应用单因素试验和三因素正交试验研究了温度、二甲基亚砜(DMSO)浓度及精子密度等因素对九孔鲍(Haliotis diversicolor supertexta)精子短期保存的影响。单因素试验结果表明:DMSO、维生素C、甘油、葡萄糖等添加剂中仅5%和7.5%DMSO有利于精子活力的保持;3个试验温度中28℃精子活力下降速度最快,其次为1℃,最慢是5℃;稀释度越高精子活力下降速度越快。正交试验中,九孔鲍精液分别在25个保存条件下保存96 h,保存期间每隔一段时间取样观察精子活力。25个处理的活力变化数据用生长函数拟合,根据拟合方程计算出精子活力半衰期,并对结果进行直观分析及方差分析。结果表明,较理想的精子保存条件是:温度为7℃,DMSO质量分数为3%,精子密度为7.5×108个/mL;各因素对精子活力半衰期的影响按精子密度、温度、DMSO密度顺序递减;精子密度对精子活力半衰期有显著影响(P<0.05),温度及DMSO浓度的影响不显著(P>0.05)。 相似文献
9.
应用单因素试验和三因素正交试验研究了温度、二甲基亚砜(DMSO)浓度及精子密度等因素对九孔鲍(Haliotis diversicolor supertextexta)精子短期保存的影响。单因素试验结果表明: DMSO、维生素C、甘油、葡萄糖等添加剂中仅5%和7. 5% DMSO有利于精子活力的保持; 3个试验温度中28℃精子活力下降速度最快，其次为1℃, 最慢是5℃; 稀释度越高精子活力下降速度越快。正交试验中, 九孔鲍精液分别在25个保存条件下保存96 h, 保存期间每隔一段时间取样观察精子活力。25 个处理的活力变化数据用生长函数拟合, 根据拟合方程计算出精子活力半衰期, 并对结果进行直观分析及方差分析。结果表明, 较理想的精子保存条件是: 温度为7℃, DMSO质量分数为3%, 精子密度为7.5×108个/mL; 各因素对精子活力半衰期的影响按精子密度、温度、DMSO密度顺序递减; 精子密度对精子活力半衰期有显著影响(P<0.05) , 温度及DMSO浓度的影响不显著(P>0.05) 。 相似文献
10.
三倍体牡蛎在繁殖季节的生长研究 总被引：2，自引：0，他引：2
研究了在繁殖季节内三倍体太平洋牡蛎的生长情况。结果表明 ,三倍体牡蛎比二倍体对照组具有明显的生长优势。在整个繁殖期间 ,三倍体的体重明显高于二倍体。三倍体的生长速度较均匀 ,而二倍体变化较大。在集中排放前体重增长较快 ,集中排放后体重增长明显减慢。三倍体的平均体重在排放前比二倍体高 17%左右 ,在排放后则高达 30 %以上。集中排放前 ,二倍体的软体重增长很快并超过了三倍体 ,其出肉率比三倍体高 2 6 .4 8%。排放后二倍体的软体重明显降低 (降低 4 8% ) ,出肉率降低 4 0 .0 % ,而三倍体变化不明显 ,出肉率仅降低 5 .79%。繁殖高峰后三倍体的软体重比二倍体高 4 1.2 2 %。三倍体牡蛎较低但稳定的出肉率表明三倍体太平洋牡蛎具有高度的不育性 ,但三倍体的不育性并不是引起三倍体生长优势的主要原因 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
16.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance. 相似文献
17.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
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Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
20.
Shigehisa Nakamura 《Marine Geodesy》2001,24(1):27-33
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake. 相似文献