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91.
长牡蛎(Crassostrea gigas)微卫星克隆快速分离及特性分析 总被引:22,自引:2,他引:22
采用磁珠杂交选择和PCR筛选法,从长牡蛎DNA选择片段文库中,快速分离含有微卫星序列的阳性克隆。结果表明,在筛选的200个白色菌落中,56个克隆含有重复次数5以上的微卫星序列,其中41个(20.5%)有随机侧翼区,可以进行引物设计,12个缺乏足够的侧翼序列,3个为中断的微卫星序列。此外,还获得两个小卫星克隆。在获得的微卫星序列中,完全的占54.7%,不完全的占20.8%,复合的占24.5%。除探针中使用的CA重复单元外,还观察到CT、ACT、CGCA、CACT、GACT、GCAC、CCTTA和CCTCA的重复序列。微卫星重复次数主要集中在5-30次之间,占71.7%,最高为60次。本研究中构建的长牡蛎(CA)n富集微卫星文库将为以后开发未知微卫星标记提供帮助。 相似文献
92.
93.
Hodaka Kawahata Mayuri Inoue Masato Nohara Atsushi Suzuki 《Journal of Oceanography》2006,62(4):405-412
The δ18O, δ13C and trace element composition of pearls collected from Ago Bay, Japan, were investigated in order to evaluate biomineralization
in the cultured pearl oyster (Pinctada fucata martensii). The oxygen isotopic data suggest that the pearls were produced around 23–24°C, mainly in June to early July, which is consistent
with their occurrence in the field. Therefore the pearls were produced under or close to isotopic equilibrium conditions,
although they showed high calcification rates (higher than 0.2–1.0 g cm− 2yr−1) under which, for example, coral skeletons (calcification rate ∼0.28 g cm− 2yr−1) often show non-equilibrium isotope partitioning. The δ13C values were ∼− 2.9‰ lower than those calculated for offshore waters under equilibrium conditions. This may be due to low-δ13C bottom waters resulting from the degradation of organic matter (OM) or to a contribution of low-δ 13C food. In the latter case, a simple mass balance calculation gives a respiration component of 14%. Twelve trace elements
of bulk pearl samples were classified into four groups on the basis of their enrichment/depletion patterns relative to seawater
and inter-element relationships: group 1, Co, Cr, Pb; group 2, Ba, Cs, U; group 3, Cu, Sn, V, and group 4, Mn, Rb, Mo. Comparison
with coral skeletons suggests that Ba and Mn (groups 2 and 4) were definitely much enriched in proteinaceous OM relative to
aragonite crystals in pearls and that V (group 3) in pearls showed only slight enrichment in the organicrich layer. By contrast,
the other elements showed small differences between both layers (enrichment factor of <3), suggesting that these elements
occur largely in aragonite crystals. 相似文献
94.
95.
An extremely dense bloom of the potentially toxic dinoflagellate Alexandrium tamarense was observed in the lagoons of Cà Pisani (Veneto, Italy) in summer 1993. The lagoons were experiencing a significant eutrophication impact, receiving waste waters from intensive fish culture plants. During their bloom dinoflagellates in the lagoons reached densities of 2 to 4 × 106 cells·dm−3 and a biomass of over 100 g·m−3. The bloom produced drastic ecological changes in the lagoons. It caused nocturnal anoxia, mortality of macrophytes and the build-up of labile organic matter in the water column. Grazing by the tintinnid Favella sp. contributed to the termination of the bloom of the flagellates. The results show that coastal aqua culture probably stimulates dinoflagellate blooms in shallow brackish lagoons. 相似文献
96.
97.
98.
T.F. Sutherland J. Galloway R. Loschiavo C.D. Levings R. Hare 《Estuarine, Coastal and Shelf Science》2007,75(4):447-458
Both acoustic and sediment surveys were carried out in the Broughton Archipelago, British Columbia, in order to map a former aquaculture site and calibrate acoustic surveys with georeferenced sediment properties. The acoustic surveys included EM3000 Multibeam (including backscatter) and QTC VIEW™ (Series IV) technologies, while the geotechnical survey entailed Van Veen grab sampling of surface sediments and associated analyses. The two acoustic technologies were consistent in their ability to identify distinct regions of seafloor characterized by rock outcrops, consolidated substrates, or gel-mud depositional fields. Both multibeam backscatter data and QTC VIEW™ number-coded classifications were extracted across a range of circular areas located at each georeferenced sampling station (radii: 2, 3, 4, 5, 8, 12, 16, 20 m). Statistical correlations were observed between backscatter and certain geotechnical properties, such as sediment porosity, sediment grain size fractions (<2 μm, silt content), and particulate sulfur concentration. The areal resolution of backscatter extraction was explored in terms of determining a sensitive calibration technique between backscatter and sediment properties. In general the highest r2 values between backscatter and sediment variables were observed across extraction radii between 8 and 20 m. Such groundtruthing techniques could be used to interpolate seafloor characteristics between sampling stations and provide a steering tool for sampling designs associated with benthic monitoring programs. 相似文献
99.
方斑东风螺养殖技术研究 总被引:2,自引:0,他引:2
本工作对方斑东风螺亲螺培育及产卵、种苗培养、幼螺养成过程中的一系列技术进行了研究,并对其行为及生态习性进行了观察.实验结果表明,在方斑东风螺养殖过程中,不同饵料培养效果的优劣顺序为牡蛎 〉鱼 〉鲆饵 〉鳗饵.在培养密度较高时,玻璃缸流水培养效果要优于静水培养.但同为低密度培养时,静水与流水效果差异不大.水泥池养殖结果显示平面养殖每平方米可养壳高15mm以下幼螺1 000~2 000个,壳高15~20mm的1 000~1 200个,壳高20~30mm以上的600~800个.使用鲍笼立体养殖亦可获得很高的成活率与生长率,将壳高20mm以上的幼螺放入鲍笼,4~5层笼叠加立体养殖,每平方米可养1 667~2 333个,笼养60d的成活率达95%以上. 相似文献
100.
模仿雄性锯缘青蟹第一腹肢,根据其在交配中的作用机制,采用常规滴管为材料,利用酒精灯灼热拉制一个前端弯曲、侧扁、管径大小接近第一腹肢的人工交接器.以无钙离子的人工海水作为青蟹人工授精的缓冲液,缓冲液中加入适量庆大霉素.首次对青蟹采用类似硬壳交配的方式,将成熟雄蟹贮精囊内的精荚和精液成功移植至雌蟹纳精囊中.结果表明精荚的人工移植不会破坏成熟雌蟹纳精囊的内环境,其内精子具正常受精能力.未交配雌青蟹精荚的人工移植没有正常产卵,但性腺得以促进发育,并能进行正常的生殖脱皮. 相似文献