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1.
池沼公鱼移殖放流试验研究   总被引:2,自引:0,他引:2  
作者于1984—1986年进行了池沼公鱼移殖放流试验研究,移入水库的池沼公鱼已能自然产卵繁殖,形成了经济群体。本文论及了移殖放流的理论依据、移殖放流技术、移殖放流效果、移殖池沼公鱼的生态效益的分析和池沼公鱼的资源管理。  相似文献   

2.
前言通常我们所见的鸟鱼(Ophiocephalus argus)(鳢鱼、黑鱼、才鱼),属于鱧形目鳢科,其代表种类栖息在南亚洲及热带非洲的淡水中。然而,北至我国黑龙江流域的江湖池沼中也有分布。  相似文献   

3.
本文报道了1942年横断鸭绿江而成的水丰水库的池沼公鱼生物学,内容包括性状变异、年龄和生长、食性、繁殖、群体结构、群体消长变化及渔业利用。水丰水库的池沼公鱼一龄体长(到尾叉的体长,后同)74毫米,体重3克;二龄体长99毫米,体重6.5克。体长体重关系式:logW=2.5306logL-1.7590。主要以浮游动物为食,但不同栖息地点食物组成有明显差异。一龄即达性成熟;性比为1♀:1.24♂;个体繁殖力905—19051粒,平均4330粒;个体繁殖力Y(百粒鱼卵)与体长L(厘米)的相关方程式为Y=58.4860L-402.7606;群体增殖速度(Vp)等于1494;4至5月在水库岸边产卵,卵粘性,水温10—15℃,约经12天孵出仔鱼。群体由1—3龄3个龄组组成,1321尾标本的平均年龄为1.15;65.1—80毫米体长组的个体为主要渔获对象,占整个渔获的65.5%。池沼公鱼是目前水丰水库第一位的经济鱼类,1982年鱼产量120万斤,占总鱼产的57.8%。    相似文献   

4.
水丰水库的池沼公鱼生物学   总被引:3,自引:0,他引:3  
本文报道了1942年横断鸭绿江而成的水丰水库的池沼公鱼生物学,内容包括性状变异、年龄和生长、食性、繁殖、群体结构、群体消长变化及渔业利用。水丰水库的池沼公鱼一龄体长(到尾叉的体长,后同)74毫米,体重3克;二龄体长99毫米,体重6.5克。体长体重关系式:logW=2.5306logL-1.7590。主要以浮游动物为食,但不同栖息地点食物组成有明显差异。一龄即达性成熟;性比为1♀:1.24σ^n;个体繁殖力905-19051粒,平均4330粒;个体繁殖力Y(百粒鱼卵)与体长L(厘米)的相关方程式为Y=58.4860L-402.7606;群体增殖速度(Vp)等于1494;4至5月在水库岸边产卵,卵粘性,水温10-15℃,约经12天孵出仔鱼。群体由1-3龄3个龄组组成,1321尾标本的平均年龄为1.15;65.1-80毫米体长组的个体为主要渔获对象,占整个渔获的65.5%。池沼公鱼是目前水丰水库第一位的经济鱼类,1982年鱼产量120万斤,占总鱼产的57.8%。  相似文献   

5.
(鱼叚)虎鱼类为暖水性和温水性小型鱼类,广泛分布于热带、亚热带和温带水域,绝大部分栖息于沿海,少数种类生活于河口及江河淡水中。据近年调查,我国淡水(鱼叚)虎鱼类约30种,较邻近国家为盛。 浙江省地处温带和亚热带季风气候区,淡水(鱼叚)虎鱼类的种类不少。最早对浙江淡水(鱼叚)虎鱼类进行研究的是Sauvage,H.E.和Dabty(1874)在“中国淡水鱼类记述”一文申报道二种(鱼叚)虎鱼类新种,一为采自宁波的戴氏塘鳢Eleotris davidi,另一为采自浙江西  相似文献   

6.
鱼喝水吗     
鱼喝水吗问:鱼喝水吗?。答:鱼类几乎栖息在地球上的所有水域里,每种鱼只能在它们特定的自然条件中生存。只有极少数鱼类才能从盐水进入淡水,或者从淡水进入盐水,而且对身体无任何损伤。淡水鱼类由于体液的盐浓度高于外界,这些成份能产生8·204X10’Pa左右...  相似文献   

7.
广东省海南黎族、苗族自治区首府通什市,最近建立了一个淡水鱼养殖试验场。该场面积共31亩,现已投放鲩鱼、鲢鱼、鳙鱼等鱼苗一万五千尾。自治区境内有许多池沼和70多座水库,这是发展淡水养鱼事业的有利条件。通什淡水鱼殖试验场的建立,将为这个自治区淡水鱼养殖事业创造经验。(转载自光明日报)  相似文献   

8.
选取16种鱼类, 对紫黑翼蚌(Potamilus alatus)钩介幼虫寄主鱼进行人工筛选试验, 结果表明: 仅在淡水石首鱼(Aplodinotus grunniens)上获得变态发育的稚蚌, 寄生变态率为(49.6±9.4)%, 但是过量寄生将导致淡水石首鱼的死亡。除眼斑拟石首鱼(Soiaenops ocellatus)外, 寄生在其他14种淡水鱼类均不可能实现钩介幼虫的变态。进一步扫描电镜观察显示: 钩介幼虫可在与淡水石首鱼同科的眼斑拟石首鱼鳃丝寄生并形成完整的包囊, 且在大规格鱼体形成包囊的速度明显快于幼鱼。但在寄生和淡水低渗双重胁迫下, 眼斑拟石首鱼出现极高的死亡率, 提示应进一步开展淡化驯养以提高眼斑拟石首鱼寄生后的成活率。其中黄颡鱼(Pelteobagrus fulvidraco)、小口黑鲈(Micropterus dolomieu) 、蓝鲶(Ictalurus furcatus)寄生后1—2d内脱落的幼虫几乎全部死亡, 推测3种鱼体中可能存在紫黑翼蚌幼虫的致死因子。综合研究表明: 紫黑翼蚌是目前发现对寄主鱼选择性最为专一的蚌类, 而眼斑拟石首鱼具有作为替代寄主鱼的潜能。  相似文献   

9.
大河之鱼     
正俗话说"鱼儿离不开水",此话固然有道理,其实,水也离不开鱼。没有鱼的水,没有生命,就是死水!谈到大河生命,一定要说一说大河里面的鱼。全球的鱼类大约有32100种,其中,大部分生活在海洋里面,约有18300种。生活在淡水里面的鱼类有13800种,占所有鱼类总数的43%。这些淡水鱼类,除少数是江海或海江洄游性鱼类  相似文献   

10.
四大家鱼,青鱼 Mylopharyngodon piceus、草鱼 Ctenopharyngodon idellus、鲢鱼 Hypopht-halmichthys molitrix、鳙鱼 Aristichthys nopilis,是我国淡水主要养殖对象。具有生长快、饵料来源广、单位产量高等优点。由于以往只能在江河流水环境中产卵繁殖,生产受到很大限制。经我国水产科学工作者反复实践,不断探索,掌握了四大家鱼的繁殖规律,取得了人工繁殖的成功,为淡水养殖的鱼苗来源开辟了新途径,推动了我国淡水渔业的发展。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

13.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

14.
15.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

16.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

17.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

18.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

19.
The review deals with study of enzymologic properties of a novel highly specific acetylcholinesterase substrate, N-(β-acetoxyethyl) piperidinium iodomethylate (“piperidylcholine”), and its 30 derivatives that were tested as effectors of cholinesterases of mammals and various species of Pacific squids. It was proven for the first time that responsible for specificity of action was structure of cyclic ammonium grouping of the alcohol part of molecule of the ester substrate. Analysis of specificity is performed based on enzymatic hydrolysis parameters—activity of catalytic center of cholinesterases and bimolecular constant of the reaction rate that are determined at optimal and low substrate concentrations. Among the specially synthesized group of thioester compounds there is revealed one more highly specific acetylcholinesterase substrate—N-(β-acetoxyethyl) piperidinium.  相似文献   

20.
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