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1.
主养青鱼高产池塘的浮游植物和有机碎屑   总被引:5,自引:1,他引:4  
本文报道了主养青鱼净产11.25、15吨/公顷·年两个产量级池塘的浮游植物和有机碎屑组成、现存量的研究结果:浮游植物丰度为20-60mg/L,有机碎屑丰度为30-70mg/L;浮游植物群落由7种优势种群交替组成,它们分别是隐藻(Cryptomonas.spp)、蓝裸甲藻(Gymnodinumcyaneum)、裸藻(Euglenaspp)、针杆藻(Synedrasp.)和菱形藻(Nitzschiasp.)、尖头藻(RaphidiopsissPP)、裂面藻(Merismopediaspp.)、绿球藻类(Chlorellaceaespp.),隐藻为主的鞭毛藻类占优势。文中还探讨了浮游植物与鱼池水质净化、浮游植物有机碎屑丰度与鱼产量的关系。  相似文献   

2.
3种饵料金藻的超低温保存研究↑(*)   总被引:13,自引:0,他引:13  
用两步冷冻法研究绿色巴夫藻(Pavlovaviridis)、湛江等鞭金藻(Isochrysiszhanjiangensis)、球等鞭金藻(I.galbana3011)的超低温保存(液氮,-196℃),探讨了影响存活率的内、外因素。结果表明,降温速率0.7℃/min,预冻温度-40℃,预冻时间30min时可获得较高的存活率。15%DMSO或15%DMSO+10%蔗糖是良好的抗冻保护剂。某些藻类在生长静止期或在低于最适温度下培养时可显著提高其存活率。通过控制内、外条件,3种金藻的存活率都可达到30%以上,比以往的报道有显著提高。  相似文献   

3.
UV-B辐射对两种海洋微藻生长的影响   总被引:13,自引:2,他引:11  
研究了两种微藻--小新月菱形与青岛大扁藻在一范围内(小新月菱形藻0~3.00j/m^2,青岛大扁藻0~11.25J/m^2)UV-B辐射对其相对增长率(K),蛋白质含量、类胡萝卜素含量以及超氧化物歧化酶(Superoxide dismutasc,SOD)活性的影响。结果表明,(1)随着辐射剂量的升高,两种微藻的相对增长率(K)逐渐下降,其各自的半数有效抑制浓度48h,EC50分别为,小新月菱形藻1  相似文献   

4.
对钝顶螺旋藻进行研究和应用过程中分离筛选,获得一直线形变异藻株(Sp-L)。长期观察培养发现,分纯得到的直线形藻株能保持稳定遗传。对其形态、生长曲线、产量、上浮性、蛋白质含量以及常见金属元素(Fe、Mn、Cu、Zn、Ca、Mg)含量进行测定,结果表明直线形变异藻株具有藻丝体长、蛋白质和常见金属元素含量与正常螺旋藻接近及易于采收等特点,为研究直线形螺旋藻提供了基础性的理论依据。  相似文献   

5.
球等鞭金藻培养液中卵形小球藻的繁殖控制方法   总被引:1,自引:0,他引:1  
张胜利 《水产科学》1995,14(1):21-23
不同藻类生长、繁殖的生态条件是不尽相同的利用球等鞭金藻(Isochysisgalbana)与其污染藻-卵形小球藻(C.ovalis)生态习性的差异,在培养过程中对藻液PH值进行人工控制,使其保持在球等鞭金藻生长的适宜范围之内,从而达到促进球等鞭金藻生长,控制卵形小球藻繁殖之目的。本文通过对3组污染程序不同的藻液的对比培养实验发现,在温度范围17-18.4℃,照度范围3000-8000Lux条件下,  相似文献   

6.
中性柠檬酸菌对几种常见藻类生长的他感作用   总被引:11,自引:0,他引:11  
在4500~4800lux光照,26~28℃的培养条件下,从绿裸藻(Euglenaviridis)水华中分离的优势菌种之一中性柠檬酸菌(Citrobacterintermedius)的分泌物对斜生栅藻(Scenedesmusobliquus)、粉核小球藻(Chlorelapyrenoidosa)、羊角月牙藻(Selenastrumcapri cormutum)、水华鱼腥藻(Anabaenaflos-aquae)和易变鱼腥藻(Anabaenavqriabilis)的生长有促进作用;对银灰平裂藻(Merismopediaglauca)、莱茵衣藻(Chlamydononasreinhardi)和铜绿微囊藻(Microcystisaerugiuosa)的生长具有抑制作用。中性柠檬酸菌胞外分泌物能促进粉核小球藻细胞个体的长大,对其他藻类主要是影响细胞的大小。中性柠檬酸菌对不同藻类影响的差异对水华过程可能具有重要意义。  相似文献   

7.
条斑紫菜色彩突变体的诱导_分离和特性分析   总被引:31,自引:4,他引:27  
严兴洪 《水产学报》2000,24(3):221-228
条斑紫菜叶状体的原生质体经化学诱变剂-N-甲基-N’-硝基-N-亚硝基胍(MNNG)处理后,在它们的再生叶状体中,出现了少量色彩发生变异的点状异体。它们的色彩变异细胞呈点状无规则地与野生细胞或其它变异细胞镶嵌在一起。这类变异体的单孢子萌发成单色变异(或野生色)叶状体以及与母体相似的点状变异体。利用单色变异叶状体分离出绿色(yel),浅桔黄色(och)以及深桔红色(bus)等三个突变株。突变株的叶状体活体吸收光谱以及藻红蛋白和藻蓝蛋白的含量与野生型相比均存在着明显的差异。经突变体支生型杂交实验证明,突变体yel和och均含一个与色彩变化有关并且符合孟德尔遗传规律的隐性变异基因。相关变异基因的着丝粒距离,在突变体yel和coh中分别为11.5和15.8图距。  相似文献   

8.
长海县核大砣子海珍品自然保护区海域的浮游动物   总被引:1,自引:0,他引:1  
长海县核大砣子自然保护区海域浮游动物的调查工作是在1990至1991年期间进行的。浮游动物种类繁多,共有11类41种及多种浮游幼虫。优势种主要为纤毛虫类中的纤毛虫SP(Ciliatasp.)、桡足类中的剑水蚤SP.(Cy-clopoidaspsp.)鞭毛虫类中的平底鼎型虫(Peuidiniumdepussum)等。年平均生物量9.4×105细胞/m3。生物量四季分布差异很大,同一季节里,全海域分布差异较小,趋于稳定。  相似文献   

9.
新分离的5种微藻是细小裂面藻(Merismopediaminima)微型小球藻(Chlorellanana)朱氏四片藻(Tetraselmischui),淡色紫球藻(Porphyridiumpurpureum)和波海红细胞藻(Rhodomaonasbaltica)试验表明5种藻在10-30℃的试验温度内都能生工成活,生长繁殖的适温范围在15-25℃,最适温度是20-25℃,在10℃和30℃时,生长  相似文献   

10.
关于玛瑙鲍的探索与研究   总被引:6,自引:1,他引:5  
选择皱纹盘鲍(Haliotis discus hannai)的变异个体--贝壳为红色的玛瑙鲍(Agate Abalone)作亲体,进行人工繁殖的培育。发现在性产物排放诱导率、孵化率、幼虫附着率和稚鲍生长等方面,玛瑙鲍与皱纹盘鲍大致相同。但稚鲍对不良环境(如赤潮)的抗性,玛瑙鲍明显强于皱纹盘鲍,32d存活率,前者为63.1%,后者为34.3%。LDH电泳图谱显示,玛瑙鲍内脏组织中LDH活性较高,而被  相似文献   

11.
ABSTRACT: We designed five 16S rRNA-targeted oligonucleotide probes (Sp probes) specific for Flavobacterium sp. 5 N-3, which inhibits the growth of red tide phytoplankton Gymnodinium mikimotoi (Dinophyceae). These probes were evaluated by whole-cell hybridization against 5 N-3 cells incubated under laboratory conditions. The fluorescence signal from the cell detected with Sp probe mix5, a mixture of the five probes, was 8.4-fold higher than that obtained with only one Sp probe (Sp01RF). The signal obtained by this method was strong enough to recognize 5 N-3 cells and count them under the epifluorescence microscope, while the signal was often undetectable when a single probe was used. Fluorescence intensities of cells at stationary phases and of 'starved' cells in sterile seawater using Sp probe mix5 were low but still sufficient for enumeration. These Sp probes did not hybridize with 11 strains from the Cytophaga/Flavobacteria/Bacteroides phylum and did react with strain 5 N-3 following whole-cell hybridization. These results show that 5 N-3 cells cultivated under our laboratory conditions can be detected by whole-cell hybridization with the five designed probes. These data also suggest that this technique may be useful for detection of an algicidal bacterium 5 N-3 in the natural environment.  相似文献   

12.
Abstract. A non-pathogenic cell culture adapted variant was obtained from a normally pathogenic strain of IPN virus (Sp type) after several passages in RTG-2 cells. This cell culture modified (CCA) strain was compared with the original wild (W) strain in various tests. Cross neutralization tests showed no obvious antigenic difference between the two. However the CCA strain was neutralized by a 1:5000 dilution of normal trout serum whereas the W strain was not. In RTG-2 cells, CCA strain gave both large and small plaques, whereas the W strain gave only small ones. Both virus strains were heat sensitive and labile to cyclic freezing and thawing. The CCA virus was more stable in storage at 4°C under different pH conditions and its growth in RTG-2 cells was more rapid. The rt (supraoptimal temperature at which viral yield is depressed by 90%) appeared to be 19-20°C for the CCA strain and 18-19°C for the W strain. Pre-treatment of RTG-2 cells with ultraviolet inactivated CCA virus could inhibit growth of W virus, but had no effect on replication of homologous virus.  相似文献   

13.
黄颡鱼瞬时耗氧率与窒息点的研究   总被引:1,自引:0,他引:1  
在水温(28.0±0.5)℃下,用封闭静水式装置测定了体长1.90~11.03 cm、体重0.17~22.99 g黄颡鱼(Pel-teobagrus fulvidraco)的瞬时耗氧率和窒息点。结果表明,黄颡鱼窒息点(Sp)为0.33~0.60 mg/L,瞬时耗氧率(IRO2)为0.0119~0.2081 mg/g.h。Sp和IRO2随规格的增加而降低,黄颡鱼窒息点(Sp)与体长(L)、体重(W)的关系式分别为:Sp=0.7795L-0.3695(R2=0.9619)、Sp=0.4897W-0.1323(R2=0.9656);瞬时耗氧率(IRO2)与体长(L)、体重(W)的回归方程为:IRO2=0.7290L-0.5709(R2=0.9580)、IRO2=0.3549W-0.2036(R2=0.9539);IRO2随水中溶解氧(DO)的下降而下降,二者之间存在明显的线性关系。黄颡鱼属低窒息点鱼类,其呼吸类型可归属于顺应型。  相似文献   

14.
Abstract. Six monoclonal antibodies (MAbs) produced against the infectious pancreatic necrosis virus (IPNV) N1 strain were used in a dot-blot assay to examine reference strains of the nine proposed serotypes and a representative selection of 81 Norwegian aquatic birnavirus isolates. These isolates had earlier been serotyped by use of a panel of 11 MAbs produced against other strains of IPNV. Correlations between the reaction patterns of the two panels of MAbs were found. All reference strains and field isolates shared two epitopes, one on VP2 and one on VP3. Seventy-seven of the field isolates reacted identically with the N1 strain (positive with all six MAbs). The Sp type strain was positive with five of the MAbs and was different from all the field strains. The other reference strains (WB, VR299, Ab, Ja, Te, He, C1, C2 and C3) were positive with two to four of the MAbs. Together with previously published data, these findings indicate that most Norwegian isolates are closely related to, or identical with, the N1 strain and belong to the Sp serotype. No correlation between the health status of Atlantic salmon and antigenicity of the isolates was found. Testing of the reference strains in ELISA revealed some discrepancies with the dot-blot results.  相似文献   

15.
条斑紫菜优良品系(LC-14)的筛选与特性分析   总被引:3,自引:1,他引:2       下载免费PDF全文
从条斑紫菜(Pyropia yezoensis)绿色突变体和红色突变体种内杂交产生的F_1叶状体中,分离出新品系LC-14。该品系的F_1叶状体在生长速度和品质等方面均显著优于条斑紫菜野生型栽培品系(WT)。日龄70 d的叶状体平均长度和湿重,LC-14品系分别为106.53 cm和3.07 g,分别是WT品系的4.39和10.27倍。培养至第55天,LC-14品系的3种主要光合色素(叶绿素a、藻红蛋白和藻蓝蛋白)含量分别为9.85 mg/g、52.09 mg/g和23.26 mg/g,分别比WT品系提高了65%、65%和49%,而其藻体的平均厚度(20.89μm)反而降低了32%。此外,LC-14品系的壳孢子放散总量为761.32×10~4 ind/壳,是WT品系的1.28倍。上述结果表明,LC-14品系具有生长快、品质优、壳孢子放散量大的优点,藻体颜色与野生色(棕褐色)相近,是条斑紫菜的优良品系,有望在生产中应用。  相似文献   

16.
A newly synthetic allopolyploid strain (SAS) was selected and established from gynogenetic offspring of gibel carp clone A+ with 156 chromosomes induced by common carp sperm with 50 chromosomes. In this study, the allopolyploid strain was detected to contain 206 chromosomes, and the growth trait was evaluated to have 25.15% growth faster than that of clone A+. Genetic marker analyses of transferrin (Tf) alleles, ITS1 sequences and mtDNA D‐loop sequences indicated that the allopolyploid strain was synthetized from maternal gibel carp clone A+ and paternal common carp, and the synthetic chromosome sets were further confirmed by genomic in situ hybridization (GISH) and chromosome localization of 45S rDNA. Significantly, the synthetic allopolyploid strain has tended to be stable by five successive generations of gynogenesis, because it still keeps unisexual reproduction mode of gynogenesis. Therefore, it will become a novel variety for gibel carp aquaculture in future.  相似文献   

17.
为了检测驯食配合饲料的大口黑鲈(Micropterus salmoides)3个选育世代群体遗传多样性水平变化,利用微卫星标记技术对驯食配合饲料大口黑鲈选育基础群体(Sp0)和第二、三和四代选育群体(Sp2、Sp3和Sp4)共240尾样品进行检测。结果显示,18个微卫星位点共获得44个等位基因。Sp0、Sp2、Sp3和Sp4的平均观测杂合度(H_o)分别为0.4895、0.4802、0.4579和0.4206,平均期望杂合度(H_e)分别为0.4615、0.4454、0.4621和0.3916,平均多态信息含量(PIC)分别为0.3791、0.3659、0.3764和0.3257。4个群体间的配对比较群体间遗传分化指数(F_(st))值在0.01612~0.16162之间、遗传距离(D_a)在0.0249~0.1434之间。遗传变异来源(AMOVA)分析显示,只有8.38%的变异来自于群体间,其余遗传变异均来自于个体间。研究表明,经连续多代选育之后,易驯食配合饲料的快长大口黑鲈选育群体具有中度遗传多样性,具备选育潜力,可继续进行选育。  相似文献   

18.
牙鲆抗鳗弧菌病家系筛选及其分析   总被引:4,自引:3,他引:1  
2007年以从养殖牙鲆(Paralichthys olivaceus)中筛选出的抗病选育群体、从日本引进的日本群体以及从黄海捕捞的野生群体为基础,进行各种组合方式的交配,建立了63个牙鲆家系;2008年又建立了30个家系。对2007年培育的59个家系和2008年培育的30个家系进行了鳗弧菌(Vibrio anguillarum)感染实验,结果表明,不同家系间的抗病力存在极显著的差异(P0.01)。从2007年培育的59个家系中筛选出4个抗病家系,鳗弧菌感染后存活率达到50%以上;2008年的30个家系中5个家系抗病力较强,鳗弧菌感染后的存活率达到60%以上。2008年培育的30个家系其4月龄和6月龄的感染后存活率的相关系数为0.403(P0.05),表明不同生长时期的感染结果具有一致性。230d的体长和体质量与对鳗弧菌的抗病力存在显著的相关关系(P0.05),皮尔森相关系数分别为0.282和0.237。研究发现,日本群体与抗病选育群体的杂交后代抗病性能表现优异,可以通过日本群体与中国群体间的杂交进行遗传改良,达到培育出高产、抗病牙鲆新品种的目的。  相似文献   

19.
Abstract. The isolation and characterization of infectious pancreatic necrosis (IPN) virus from a goldfish, discus fish and bream is described. The fish from which the isolates were recovered showed no pathological signs of IPN. All three virus isolates were neutralized by antiserum to IPN, strain Ab, but not by antiserum to the Sp or VR-299 strains. They were morphologically identical to IPN virus in negative stain electron microscopy, grew in the cytoplasm of BF-2 cells, as shown by immuno-fluorescence and, like IPNV, were stable to heating, lipid solvents and acid pH.  相似文献   

20.
福瑞鲤2号不同生长速率个体肌肉组织转录组分析   总被引:3,自引:0,他引:3       下载免费PDF全文
鱼类通过选育获得优良生长性状的遗传分子机制目前尚不清楚。实验分析比较了2种不同生长速率福瑞鲤2号肌肉组织的转录组文库。组装后共获得392 238条测序序列(contigs)。其中可比对上斑马鱼、弓斑东方鲀、青鳉、三刺鱼、尼罗罗非鱼和松浦镜鲤的蛋白序列的比例为56.01%~77.71%。2种不同生长速率福瑞鲤2号肌肉转录组比较,获得749个差异表达基因,包括348个上调基因和401个下调基因。鉴定出了与肌肉生长相关关键基因,如mb、myl2b、tnni1、fhl1、lamb3和pdk2等。研究结果为后续基因功能的研究以及鱼类新品种优良生长性状的分子机制解析奠定了基础。  相似文献   

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