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1.
《中国海洋大学学报(自然科学版)》2010,(Z1)
采用低渗抑制受精卵第2极体(PB2)的释放诱导栉孔扇贝(Chlamys farreri)三倍体。水温20℃时,分别进行不同盐度处理(8~20)、不同起始处理时间(受精后15~40 min)和不同持续处理时间(10~25 min)的实验,对三倍体处理组和对照组幼虫的生长进行观察,同时将低渗、6-DMAP、热休克、冷休克4种诱导方法进行对比。结果表明:受精后30 min开始处理20 min,诱导率最高,可达(92.36±2.41)%,卵裂率为(49.78±6.51)%,孵化率为(61.82±1.63)%;D形幼虫期,处理组幼虫表现出明显的生长优势(P0.01),不仅生长速度快,而且发育到变态时个体比二倍体大;低渗诱导的三倍体率与6-DMAP相比无显著差异(P0.05);与热休克和冷休克相比差异显著(P0.01)。 相似文献
2.
基于2×2交叉实验设计,通过杂交和6-DMAP等诱导处理,构建了二倍体自交组、二倍体杂交组、三倍体诱导自交组和三倍体诱导杂交组等四个实验组家系,探讨了海湾扇贝(Argopecten irradians)幼虫期生长及存活的杂种优势和6-DMAP诱导处理效应的复合作用。分别计算各家系的孵化率,测定了各家系幼虫期第1、5、10天幼虫个体的壳长以及第5天和第10天各家系幼虫的存活率。利用一般线性模型(general linear model (GLM))计算表型变量的原因方差组分,评估了杂交和6-DMAP处理对扇贝幼虫生长和存活的影响。结果显示:6-DMAP处理组孵化率要显著低于非处理实验组(P0.05)。三倍体诱导自交组第5天幼虫存活率显著低于其他组(P0.05),到第10天三倍体自交组全部死亡。三倍体诱导杂交组第10天存活率低于二倍体组但不显著(P0.05)。在第1天幼虫生长中,三倍体诱导杂交组幼虫壳长显著小于其他组(P0.05),第5天幼虫生长中,三倍体诱导杂交组壳长则显著大于其他组,而三倍体诱导自交组则显著小于其他组(P0.05)。在第10天幼虫生长中,二倍体自交组显著小于二倍体杂交组和三倍体诱导杂交组组(P0.05)。上述结果显示扇贝幼虫生长期的杂种优势和三倍体诱导效应间存在一定相互作用。 相似文献
3.
初步探讨了利用高盐抑制受精卵第2极体(PB2)的释放的方法诱导太平洋牡蛎(Crassostrea gigas)三倍体。水温25℃条件下,分别进行不同高盐处理(盐度梯度为40、45、50、55、60、65、70、75、80)、不同处理时机(受精卵出现第一个PB1,30%和50%PB1,出现第一个PB2,50%PB2)和不同持续处理时间(10~25min)的实验,通过胚胎孵化率、三倍体诱导率及综合评价指数的分析表明,高盐诱导太平洋牡蛎三倍体的最适方案为:当50%受精卵出第一极体时,以盐度为65的高盐海水处理受精卵20min,三倍体诱导率最高达65.53%。 相似文献
4.
《中国海洋大学学报(自然科学版)》2020,(Z1)
以葡萄牙牡蛎(Crassostrea angulata)为研究对象,分别使用6种介质(NaCl、KCl、CaCl_2、MgCl_2、蔗糖、海水)配制的梯度低渗溶液,在40%～50%受精卵出现第一极体(PB1)时处理15 min,进行三倍体诱导。研究表明,对于同种介质,卵裂率和孵化率均随渗透压升高而增大,三倍体诱导率则先增后减,在渗透压为P_8(盐度为8的海水渗透压)时达到最高。在同一渗透压P_8条件下,除CaCl_2组外,各组卵裂率、孵化率、诱导率与低渗海水组相比无显著差异(P0.05),CaCl_2组卵裂率、孵化率降低,而诱导率显著较高(P0.05)。各低渗组卵裂率、孵化率均低于自然海水组。研究结果表明,低渗海水法诱导贝类三倍体时物理的低渗因素发挥主要作用,Ca~(2+)可能起到辅助作用。 相似文献
5.
采用0.25 mg/L、0.5 mg/L、0.75 mg/L、1.0 mg/L细胞松弛素B(CB)抑制第二极体(PB2)的释放诱导菲律宾蛤仔三倍体,观察三倍体蛤仔的早期胚胎发育。结果表明:CB的浓度对菲律宾蛤仔三倍体的诱导以及胚胎发育影响显著(P<0.05),0.5与0.75 mg/L CB处理组诱导率较高,分别达89.4%与89.2%;各组第一极体(PB1)同步释放,处理组PB2受到明显抑制;CB处理浓度与胚胎发育速度呈负相关,与各发育阶段的畸形率及畸形程度呈正相关。综合诱导率及早期胚胎发育状况,0.5 mg/L是CB诱导菲律宾蛤仔三倍体的适宜浓度。 相似文献
6.
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
7.
《中国海洋大学学报(自然科学版)》2021,(Z1)
本研究采用了细胞松弛素B (CB)和6-二甲基氨基嘌呤(6-DMAP)两种诱导方法对长牡蛎(Crassostrea gigas)壳橙品系进行三倍体诱导,分析了两种诱导方法的不同条件下幼虫的三倍体率、孵化率、D形幼虫畸形率以及幼虫生长和存活。研究表明,虽然细胞松弛素B (CB)和6-二甲基氨基嘌呤(6-DMAP)诱导的三倍体率差异不显著(P0.05),但同种方法中不同处理条件下长牡蛎壳橙品系的三倍体率、孵化率和D形幼虫畸形率差异显著(P0.05)。综合三倍体率、孵化率、D形幼虫畸形率这三个指标;在水温25～27℃、盐度30、受精后15 min时,使用浓度为0.5 mg/L的CB溶液,持续诱导20 min为CB诱导的最适诱导条件;在水温25～27℃、盐度30、受精后15 min时,使用浓度为300μmol/L的6-DMAP溶液,持续诱导15 min为6-DMAP诱导的最适诱导条件。幼虫生长和存活的观察结果表明,三倍体诱导组与对照组生长差异显著(P0.05),CB诱导组和6-DMAP诱导组的幼虫壳高平均日增量分别为(15.83±1.44)μm和(15.27±0.48)μm,均高于对照组(12.10±0.42)μm;三倍体诱导组与对照组幼虫存活率差异不显著。研究结果为长牡蛎壳橙品系的遗传改良提供了参考资料。 相似文献
8.
采用低盐度(4、6、8、10、12、14、16)和高盐度(40、45、50、55、60、65、70)在40%~50%受精卵出现第一极体时处理10和15min,进行长牡蛎三倍体的诱导。在低盐度诱导三倍体实验中,随着盐度降低,D型幼虫孵化率逐渐降低,处理10和15min的卵裂率差异显著(P0.05),孵化率差异不显著(P0.05)。当盐度为8时,处理受精卵10与15min,三倍体诱导率最高分别可达84.4%和91.0%,两处理组三倍体诱导率差异显著(P0.05)。在高盐度诱导三倍体实验中,随着盐度升高,D型幼虫孵化率逐渐降低,处理10和15min的卵裂率和孵化率均差异显著(P0.05)。当盐度为55时,处理受精卵10min,三倍体诱导率最高为80.3%;当盐度为60时,处理受精卵15min,三倍体诱导率最高为97.1%,两处理组三倍体诱导率差异显著(P0.05)。研究发现,在盐度为8和60条件下,40%~50%的受精卵出现第一极体时,处理15min,长牡蛎三倍体诱导率最高。 相似文献
9.
本文以中国太平洋牡蛎二倍体自交作为对照,比较了诱导三倍体群体及其杂交三倍体的早期表型性状.通过对各试验组卵径、卵裂率、D幼率、D形幼虫大小、生长、存活率和倍性等指标进行测定,进一步评估了2种诱导方法的有效性.结果表明:与诱导三倍体群体相比,杂交三倍体表现出明显优势,D幼率、D形幼虫大小均大于诱导三倍体群体,且差异显著(P＜0.05);稚贝期壳长和壳高生长也显著快于诱导三倍体群体(P＜0.05).至附着,杂交三倍体的存活率很高,显著优于诱导三倍体群体.就三倍体率而言,杂交三倍体达到100％,而诱导三倍体群体仅为51.00％士11.79％.由上得知,杂交三倍体更适合应用于大规模生产. 相似文献
10.
用6-二甲基氨基嘌呤(6-DMAP)进行了黄河口近江牡蛎(Crassostreaariakensis)的三倍体诱导,以卵裂率、孵化率、诱导三倍体率和三倍体诱导组幼虫的生长率、存活率、三倍体率为指标,研究了诱导浓度、起始诱导时间、诱导持续时间三个因素对黄河口近江牡蛎三倍体的诱导效果。结果表明,三因素对近江牡蛎三倍体诱导效果的影响程度为起始诱导时间诱导持续时间诱导浓度。温度25℃,诱导浓度为300—450μmol/L,起始诱导时间为受精后14min,诱导持续时间为15min时,诱导三倍体率可达51.39%—71.67%,卵裂率、孵化率、幼虫壳高日平均生长率和幼虫平均存活率分别能达到65.16%—81.57%、61.25%—86.78%、8.76—9.88μm/d、69.16%—73.29%,眼点幼虫时期三倍体率达53.33%—62.16%。本研究为黄河口近江牡蛎的三倍体诱导提供了理论依据。 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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15.
《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