渔业污水中大型蚤（Daphainmagna straus）反馈养殖的研究

利用排放的渔业污水先进行单胞藻的培养，再接种培养大型蚤，对栅列藻密度的经时变化，大型蚤种群增长及水体中氮，磷，培养过程中的变动作了测定与分析。     

单胞藻液细胞计数的比色法

引言单胞藻的研究和生产(如饵料)中,细胞计数是一项经常必需进行而又比较繁琐的工作。和一般生物生长的规律一样,单胞藻的生长亦表现出S形的生长大曲线。这就是在人工培养单胞藻的过程中(在静止、开放和具有限定的营养条件下),自接种后,一     

冬季培养花鲈仔稚幼鱼饵料及其营养强化的初步研究

采用自选单胞藻代替小球藻调节育苗池水质和对轮虫，卤虫营养强化；控制水温15－20℃，光照4400Lux以上，换水20－30％等培养轮虫；以及按卤虫总量的2．5－3．0％的浓鱼油胶丸营养强化卤虫等技术措施，使仔稚幼鱼从0龄至47日龄存活率达到64．80％以上，47日龄至90日龄存活率达到80．71％。     

海洋浮游单胞藻在海产动物育苗中生产性培养新方法的试验研究

本文提出了一种在中继培养以后.以1∶1接种不施肥培养的新方法.此法能在两天内培养出育苗生产所要求的高浓度饵料液,饵料液的氨氮含量及三态氮总量较常规培养分别降低约70倍及10倍.可节省营养盐用量50％.此法适用于目前北方常用的几种海洋浮游单胞藻。     

文蛤幼体的摄食生态研究

通过文蛤幼体对几种单胞藻的摄食及饥饿实验，研究了几种单胞藻的饵料效果及适宜投饵密度，幼体营养贮存饱和点（ＰＲＳ）和幼体发育变态不可恢复点（ＰＮＲ）．等边金藻和扁藻为文蛤幼体的适宜饵料，混合投喂效果更佳．饵料的适宜密度为：扁藻０．５～１万／ｍＬ，等鞭金藻２．５～５万／ｍＬ，混合投喂（金藻＋扁藻）（１．２５＋０．５）万／ｍＬ．老化金藻藻液对幼体的生长发育有限制作用．文蛤幼体的ＰＮＲ和ＰＲＳ５０各为５ｄ左右     

单胞藻投饵量对西施舌稚贝摄食率的影响

实验室内用静水实验方法研究西施舌稚贝的摄食率与单胞藻投饵量、摄食时间的关系,结果表明单胞藻投饵量在适宜的范围之内,随着投饵量的增加,摄食率也随之增加,而超过一定范围时,摄食率有所下降,西施舌稚贝的摄食率在投喂饵料2 h后逐步下降.     

几种单胞藻对火腿许水蚤脂肪酸组成的影响

采用气相色谱分析法测定了几种常用单胞藻及其投喂培养的火腿许水蚤的脂肪酸组成．结果表明，金藻8701和三角褐指藻分别具有较高的DHA和EPA含量，比较适合作为桡足类饵料．金藻8701及其与三角褐指藻、绿色巴夫藻、亚心形扁藻等组合作为混合饵料投喂时，培养的火腿许水蚤的几种重要必需脂肪酸（ARA、EPA、DHA）的含量都较高，其中，以金藻8701和绿色巴夫藻按体积比1：1作为混合饵料时，火腿许水蚤的DHA／EPA值接近2：1，更有利于其作为海水仔稚鱼的优质饵料．     

渔业污水中大型蚤(Daphnia magna straus)反馈养殖的研究

利用排放的渔业污水先进行单胞藻的（栅列藻ＳｃｅｎｅｄｅｓｎｕｓｏｂｌｉｑｕａｓＴｕｒｐ）培养，再接种培养大型蚤，对栅列藻密度的经时变化，大型蚤种群增长及水体中氮、磷、钾在培养过程中的变动作了测定与分析．研究结果：①悬浮栅列藻在渔用污水中密度变动状态，开始时在充气、直接光照条件下以逻辑斯谛（Ｌｏｇｉｓｔｉｃ）曲线增长；在投放大型蚤并停止充气与直接光照后，则呈直线型下降．②大型蚤在接种进入含栅列藻的渔业污水后，在静态条件下其种群密度亦是按逻辑斯谛曲线增长．③以大型蚤间收式一次累加收获量作为种群总增长量（产出量），其累加数量及干湿重生物量数学模型均呈双对数曲线．④在间收式培养期间，大型蚤密度动态模型为一复合型指数函数．⑤渔用污水经栅列藻及大型蚤培养后再排放水体中氮、磷、钾含量分别下降了８５．５％，８１．１４％，７７．８９％．本研究结果既为枝角类集约化培养技术提供了生态学理论参数，也为污水调控及资源化提出一个良好的技术途径．     

饵料密度对紫彩血蛤幼虫生长发育的影响

用四种单胞藻分别以三个不同的密度投喂紫彩血蛤幼虫,据幼虫生长发育速度、存活率和变态率,比较不同饵料密度的效果。培养初期饵料密度控制在２．５万个／ｍＬ,两天后密度逐渐增加至５万个／ｍＬ,后期则以１０万个／ｍＬ为好。四种饵料中球等鞭金藻的效果最好。     

几种藻对卤虫养殖效果的比较研究

用不同单细胞海藻、混合单细胞淡水藻和螺旋藻分别养殖卤虫的结果表明：单一盐藻养殖的效果最佳，可使卤虫完成正常的生长、发育及繁殖；螺旋藻的效果最差，它几乎不能为卤虫滤食；三角褐指藻、紫球藻、混合淡水单胞藻也明显地比盐藻差。盐藻有可能成为对虾苗饵和海产动物生态养殖的适用藻种。     

单细胞海热模拟生烃研究

以单细胞海藻为材料进行热模拟生烃试验,对其不同温度级别下作了气体成分分析、族组份分析、热解色谱测试分析,从常温到250℃,单细胞海藻中有机物质未成熟,但具有很强的生烃能力,300－400℃达到成熟阶段,热模拟试验结果表明单细胞海藻是良好的生烃的高峰期,400－500℃时单细胞海藻中的有机质已经达到过成熟阶段,为产气为主,热模拟试验结果表明单细胞海藻是良好的生烃原始母质,并较清晰地显示出了单细胞海藻的热演化和生烃历程。     

硅藻和淡水绿藻的77K低温荧光特性的研究

实验测定了9种单细胞藻包括：5种淡水绿藻雪衣藻Chlamydomonas nivalis UTEX2765、椭圆小球藻Chlorella ellipswal CH、绿球藻Chloroccum tatrense UTEX2227、斜生栅藻Scenedesmus obliqnus、雨生红球藻Haematococcus sp．CSIRO：CS-321和四种硅藻三角褐指藻Phaeodactylum tricornutum、牟氏角毛藻Cheatoceros mulleri CH、中肋骨条藻Skeletonema costatum、尖刺拟菱形藻Pseudcrnitzsehia pungens Grunow的77K荧光光谱,并与大型海洋绿藻、其它杂色藻以及高等植物菠菜进行了比较。结果表明,9种单细胞藻都缺少作为高等植物PSI主要表征的730nm长波荧光峰。9种单细胞藻的荧光主峰的位于684nm,而淡水绿藻在714nm还有一个明显的发射峰。这个结果与海洋管藻目绿藻和某些大型海洋绿藻的荧光特性一致。四种硅藻也有一个明显的荧光发射主峰位于684～686nm,类囊体膜的荧光光谱中在700nm附近有个不明显的肩峰。以上结果表明,淡水绿藻和硅藻PSI缺少730nm长波荧光峰可能具有其普遍性,预示这些藻类在PSI结构以及能量传递等方面与高等植物具有很大的差异。     

Origin of the algae

Eukaryotic algae are traditionally separated into three broad divisions: the rhodophytes, the chromophytes and the chlorophytes. The evolutionary relationships between these groups, their links with other eukaryotes and with other photosynthetic groups, such as euglenophytes and cryptophytes, have been the subject of much debate and speculation. Here we analyse partial sequences of the large (28S) cytoplasmic ribosomal RNA from ten new species of protists belonging to various groups of unicellular algae. By combining them with the homologous sequences from 14 other unicellular and multicellular eukaryotes, we show that rhodophytes, chromophytes and chlorophytes emerge as three distinct groups late among eukaryotes, that is, close to the metazoa-metaphytes radiation. This implies a relatively late occurrence of eukaryotic photosynthetic symbiosis. We also provide details of intra- and inter-phyla relationships.     

大麦草抑制淡水藻类生长的实验研究

大麦草（Ｂａｒｌｅｙｓｔｒａｗ）对于包括单核藻和丝藻在内的多种淡水藻类有生长抑制作用。在实验过程中，水中无机盐含量变化很大，ｐＨ值和电导随着时间有缓慢增加趋势。特别是当大麦草含量超过１２０ｇ／Ｌ（湿重）时，对藻类生长有较强的抑制作用。水中ＮＯ３—Ｎ被耗尽及无脊椎动物数量的增加，都有可能是造成抑制作用的直接或间接原因。     

2种江蓠凝集素的抑藻和抗菌作用

血凝实验发现真江蓠凝集素对4种供试血红细胞均有凝集作用,其中对兔血红细胞的凝集作用最强,而细基江蓠凝集素只对兔血红细胞具有凝集活性;在对8种单细胞藻的凝集实验中,它们都只对塔玛亚历山大藻有凝集作用,对其他单细胞藻不具凝集作用;抑藻、抑菌实验表明,2种江蓠凝集素对棕囊藻的生长都具有一定的抑制作用,对玉米大斑病菌、黑曲霉和圆弧青霉等真菌菌丝生长具有不同程度的抑制作用,在供试的3种细菌中,只对枯草芽孢杆菌有抑制作用.     

Cell cycle and cell signal transduction in marine phytoplankton

tAs unicellular phytoplankton, the growth of a marine phytoplankton population results directly from the completion of a cell cycle, therefore, cell-environment communication is an important way which involves signal transduction pathways to regulate cell cycle progression and contribute to growth, metabolism and primary production and respond to their surrounding environment in marine phytoplankton. Cyclin-CDK and CaM/Ca²⁺ are essentially key regulators in control of cell cycle and signal transduction pathway, which has important values on both basic research and applied biotechnology. This paper reviews progress made in this research field, which involves the identification and characterization of cyclins and cell signal transduction system, cell cycle-control mechanisms in marine phytoplankton cells, cell cycle proteins as a marker of a terminal event to estimate the growth rate of phytoplankton at the species level, cell cycle-dependent toxin production of toxic algae and cell cycle progression regulated by environmental factors.     

基于形状特征的硅藻显微图像自动识别

硅藻是一类广泛分布于各类生境的单细胞生物,在许多领域具有广泛的应用,如水质监测、环境调查、石油勘探等,而这些应用都离不开对硅藻的种类鉴定.根据硅藻显微图像的形状特点,提出了对其进行预处理、分割、形状特征提取和分类的自动识别方法.采用了基于累积直方图的双轮廓叠加法的图像分割方法,可以有效抑制光照强度不一致、不平衡的影响,并充分利用显微镜下硅藻图像的轮廓特点,获得较好分割效果.同时对硅藻图像提取几何描述全局特征及形状签名特征,最后采用了基于误差反向传播算法的多层前馈网络(BP网络)进行分类.实验表明,该方法对11种浮游硅藻(包括12类轮廓)的自动识别率达到96.6%.     

Parasitic, amoeboid dinoflagellates

SEXUAL reproduction has so far been unknown among the Dinococcales, unicellular brown algae belonging to the Dinophyceae (dinoflagellates). As we report here, however, the life cycles of two members of this group, Stylodinium sphaera and Cystodinedria inermis, include a parasitic amoeboid stage which brings about vegetative reproduction and also possibly sexual reproduction. We believe that the two amoeboid forms have previously been identified mistakenly as a separate taxon of protozoon.     

A rhodopsin is the functional photoreceptor for phototaxis in the unicellular eukaryote Chlamydomonas

Rhodopsin is a visual pigment ubiquitous in multicellular animals. If visual pigments have a common ancient origin, as is believed, then some unicellular organisms might also use a rhodopsin photoreceptor. We show here that the unicellular alga Chlamydomonas does indeed use a rhodopsin photoreceptor. We incorporated analogues of its retinal chromophore into a blind mutant; normal photobehaviour was restored and the colour of maximum sensitivity was shifted in a manner consistent with the nature of the retinal analogue added. The data suggest that 11-cis-retinal is the natural chromophore and that the protein environment of this retinal is similar to that found in bovine rhodopsin, suggesting homology with the rhodopsins of higher organisms. This is the first demonstration of a rhodopsin photoreceptor in an alga or eukaryotic protist and also the first report of behavioural spectral shifts caused by exogenous synthetic retinals in a eukaryote. A survey of the morphology and action spectra of other protists suggests that rhodopsins may be common photoreceptors of chlorophycean, prasinophycean and dinophycean algae. Thus, Chlamydomonas represents a useful new model for studying photoreceptor cells.     

Ancestral chloroplast genome in Mesostigma viride reveals an early branch of green plant evolution

Sequence comparisons suggest that all living green plants belong to one of two major phyla: Streptophyta (land plants and their closest green algal relatives, the charophytes); and Chlorophyta (the rest of green algae). Because no green algae are known that pre-date the Streptophyta/Chlorophyta split, and also because the earliest diverging green algae show considerable morphological variation, the nature of the unicellular flagellate ancestor of the two green plant phyla is unknown. Here we report that the flagellate Mesostigma viride belongs to the earliest diverging green plant lineage discovered to date. We have sequenced the entire chloroplast DNA (118,360 base pairs) of this green alga and have conducted phylogenetic analyses of sequences derived from this genome. Mesostigma represents a lineage that emerged before the divergence of the Streptophyta and Chlorophyta, a position that is supported by several features of its chloroplast DNA. The structure and gene organization of this genome indicate that chloroplast DNA architecture has been extremely well conserved in the line leading to land plants.