Phylogenetic relationships of five species of Dorippinae(Crustacea, Decapoda) revealed by 16S rDNA sequence analysis

A molecular phylogeny is presented for the subfamily Dorippinae (including 9 individuals, representing 5 species and 4 genera), based on the sequence data from 16S rRNA gene. Two-cluster test between lineages in these phylogenetic trees has been performed. On the basis of rate constancy, the rate of nucleotide substitutions of 16S rDNA sequence data is estimated as 0.27% per million years. The analysis strongly supports the recognition of the Dorippinae as a monophyletic subfamily. Phylogenetic tree indicates that the subfamily Dorippinae is divided into two main clades, and genus Dorippe appears basal in the subfamily, diverging from other species 36.6 Ma ago. It is also clear that the Heikea is closely related to the genus Neodorippe. The divergence time between them is 15.8 Ma.     

日本鳗鲡(Anguilla japonica)和欧洲鳗鲡(A. anguilla)的微卫星差异

采用PCR扩增单位点微卫星的方法研究了日本鳗鲡(Anguilla japonica)和欧洲鳗鲡(A. anguilla)的遗传差异.结果表明,微卫星等位基因数目分布范围为8-26,35组被试(5个分类单元各7个位点)的显著性检验的结果表明其杂合性显著缺乏(P＜0.01),日本鳗鲡的4个亚种群的所有微卫星位点均偏离哈-温平衡,对日本鳗鲡种群分化进行的正合检验结果也否定了种内个体随机分布的假设.FST值为0.0098(P=0.00048)揭示了日本鳗鲡亚种群内存在较弱但显著的遗传分化.各分类单元间的FST及RST逐一对应矩阵显示了日本鳗鲡与欧洲鳗鲡两个远缘种之间存在显著差异.计算Goldstein的遗传距离并由此推算出两个种的分化时间约为200多万年.     

日本(虫寻)人工育苗技术的初步研究

日本(虫寻)[Charybdis(charybdis)japonica]系大型海产食用蟹类之一。它遍布我国沿海,日本、朝鲜、马来西亚、红海等地也有分布。这种蟹属沿岸种类,移动性小,且生长快,繁殖期长,系多次产卵的种类,是一种经济海水增殖品种。 关于日本(虫寻)苗种生产及增养殖的研究,在国内尚无所闻,在国外也未见有关苗种生产及增殖的系统报道。我们于1986年7月上旬至     

褐藻酸降解菌在海带绿烂病发生中的作用

从海带幼苗上病烂明显处分离得到 2 3株褐藻酸降解菌 ,并对其菌落形态、细胞形态及革兰氏染色反应等进行了观察。通过对褐藻酸钠的降解实验 ,筛选出 4株具较高降解能力的菌株。感染实验表明 ,分离到的褐藻酸降解菌为海带幼苗病烂的主要病原菌。     

养殖的日本鳗鲡肠道中细菌的数量和组成

用稀释滴种的定量方法，分别于甘露醇卵黄多黏菌素、马铃薯葡萄糖、伊红美蓝、链球菌琼脂、CDC厌氧琼脂和营养琼脂中分离计数不同饵料投喂阶段在饱食和空腹状态下养殖的日本鳗鲡肠道中细菌的数量和组成．结果表明：在空腹状态下，其细菌数量约为10^4～10^7个／g；在饱食状态下约为10^4～10^8个／g．在空腹状态下其肠道菌群组成以厌氧菌为主，其次为大肠菌群，再者为芽孢杆菌，未分离到肠球菌．在饱食状态下其肠道菌群以厌氧菌为主，红虫投喂期其次为大肠菌群，而肠球菌占第三位；白仔料投喂期大肠杆菌、肠球菌和芽孢杆菌的数量相当；黑仔、幼鳗、成鳗期芽孢杆菌数量占第二，大肠杆菌数量占第三．在饱食和空腹状态下，其肠道菌群数量以红虫投喂期的为最高，随着养殖时间的延长，肠道菌群数量下降．     

日本刺沙蚕Neanthes japonica (Iznka)大规模育苗的初步研究

结合生产实践 ,模拟野外温度、盐度等环境条件 ,在较大规模的育苗池环境条件下 ,对日本刺沙蚕胚胎和发育作了生殖生物学的观察和描述 ,为人工增养殖日本刺沙蚕提供了基础资料     

三十烷醇对海带叶绿体超微结构的效应

本文将经不同浓度三十烷醇处理的海带进行电镜切片观察,结果表明经三十烷醇处理后的海带,其叶绿体形态发生显著改变。与对照组相比,叶绿体中的类囊体片层增多,基质浓厚,其外形更为饱满,光合作用的强弱与类囊体片层的多少关系密切。文中从细胞学的水平上分析了三十烷醇促进海带增产的内在原因。     

赤潮异弯藻(Heterosigma akashiwo)对蒙古裸腹溞(Moina mongolica)和日本新糠虾(Neomysis japonica)的毒性影响

采用生物急性和慢性毒性实验的方法,研究了赤潮异弯藻对蒙古裸腹溞和日本新糠虾的毒性影响,并初步探讨了赤潮异弯藻导致二者较快死亡的机制。结果发现,赤潮异弯藻不仅对蒙古裸腹溞和日本新糠虾的存活有显著影响,而且使其个体变小、产幼前发育时间延长、总生殖量降低、平均存活时间缩短,种群数量增长受抑制。显微观察发现,蒙古裸腹溞能摄食赤潮异弯藻,但摄食后,其粪便紧紧地粘在蒙古裸腹溞的肠道末端;日本新糠虾不摄食赤潮异弯藻,但该藻粘附在其触须、附肢以及腹部、尾部的刚毛上,以及作为食物的卤虫幼体也被大量粘附在一起,聚集成团,或通过赤潮异弯藻粘附在日本新糠虾的附肢上。因此赤潮异弯藻很可能通过干扰蒙古裸腹溞和日本新糠虾正常的生理活动,而导致其快速死亡。     

Effects of mercuric chloride on antioxidant system and DNA integrity of the crab Charybdis japonica

Mercury (Hg) is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion (Hg²⁺) (at two final concentrations of 0.0025 and 0.0050 mg L⁻¹, prepared with HgCl₂) on metallothionein (MT) content, DNA integrity (DNA strand breaks) and catalase (CAT) in the gills and hepatopancreas, antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the hemolymph, gills and hepatopancreas of the portunid crab Charybdis japonica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation with Hg²⁺ dose and time in the hepatopancreas and a negative correlation with Hg²⁺ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire experiment; SOD and GPx in the three tissues were stimulated after 12 h, both attained peak value and then reduced during the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the detoxification strategies against Hg²⁺ in three tissues of C. japonica.     

植物激素对海带配子体克隆附着的影响

实验研究 2 ,4 - D、KT、IAA、NAA四种植物激素对海带配子体克隆附着的影响。结果表明 :2 ,4 - D对附着有较明显的促附着作用 ,最有效浓度为 2 .5mg/L 和 5mg/L,其 4 h的附着率分别是对照的 2 .79倍和 2 .95倍 ;KT的作用较复杂 ,在浓度为 1mg/L 时 ,对附着有明显的促进作用 ,其 4 h的附着率是对照的 2 .3倍 ;IAA对配子体附着没有明显的促进或抑制作用 ;NAA对附着有抑制作用 ,浓度越高 ,抑制作用越强。