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11.
利用微卫星分子标记对青蟹东海三门湾野生群体和浙江三门养殖群体的遗传多样性进行分析。6个微卫星位点在2个青蟹群体中共检测到66个等位基因,多态信息含量为0.746 ~ 0.895,均表现为高度多态性,可有效应用于青蟹遗传多样性的研究。青蟹野生群体与养殖群体的等位基因数分别为4 ~ 18,6 ~ 14,平均杂合度分别为0.577,0.561,平均多态信息含量分别为0.779,0.828;群体间遗传分化指数FST值为0.0317,遗传相似性指数为0.7930,遗传距离为0.2319。结果表明,青蟹野生与养殖群体的遗传多样性均较丰富,群体间存在一定的遗传分化。 相似文献
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为了深入了解宝天曼自然保护区树种的多样性,参照巴拿马巴罗克罗拉多岛样地的技术规范,于2009年在河南宝天曼国家级自然保护区建立了1块面积为1hm2的短柄枹林永久监测样地。对样地内所有胸径≥1cm的木本植物进行了详细的定位调查。结果表明:样地内被监测的树木个体数为2 481个,隶属于27科47属71种;短柄枹林样地共分为4个基本层次,乔木Ⅰ层主要有短柄枹(Quercus serrata var.brevipetiolata)和栓皮栎(Quercus variabilis),乔木Ⅱ层主要由四照花(Cornus kousa subsp.Chinensis)、水榆花楸(Sorbus alnifolia)组成,灌木层的优势种为连翘(Forsythia suspensa)、满山红(Rhododendron mariesii)等,草本层主要由细叶薹草(Carex duriu-sata subsp.stenophylloides)等组成;样地植物区系以北温带成分为主,共25个属,占总属数的50.98%,兼具热带成分,共10个属,占总属数的21.28%;短柄枹(Quercus serrata var.brevipetio-lata)和栓皮栎(Quercus variabilis)在群落中占有绝对的优势地位,但从径级结构来看,栓皮栎的更新较差;从物种的空间分布格局中可以看出,样地物种空间分布格局整体上表现为随机分布为主,但优势种短柄枹和栓皮栎主要表现为聚集分布。 相似文献
14.
通过分子生物学方法,克隆得到锯缘青蟹(Scylla serrata)精氨酸激酶(Arginine Kinase,AK)开放阅读框基因序列.测序结果显示:该开放阅读框基因的序列长度为1 071 bp,编码356个氨基酸残基;该序列登录Genbank(GQ:851626),序列比对结果显示,锯缘青蟹精氨酸激酶与凡纳滨对虾(Litopenaeus vannamei)精氨酸激酶的氨基酸序列同源性高达94%,与岸蟹(Carcinus maenas)、中华绒鳌蟹(Eriocheir sinensis)等甲壳类动物的精氨酸激酶也有较高的同源性,均高于90%;将克隆得到的锯缘青蟹精氨酸激酶基因与pGEX-4T-3载体连接,转化大肠杆菌BL21,经IPTG诱导得到分子质量为65 ku的融合表达蛋白(GST-AK),经兔抗锯缘青蟹精氨酸激酶多克隆抗体的免疫印迹分析证实,GST-AK具有抗原性. 相似文献
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[目的]筛选蛇足石杉中石杉碱甲的酶法提取的最佳提取条件。[方法]采用纤维素酶酶解细胞壁,从而溶出更多的蛇足石杉细胞中的物质,并设计正交试验选出酶法提取的最佳提取条件。[结果]蛇足石杉中石杉碱甲的酶法提取的最佳工艺条件为纤维素酶用量0.125 g,酶解pH4.5,酶解温度60℃,酶解时间2.5 h;在此条件下,蛇足石杉中石杉碱甲的提取率为0.589‰;各因素中温度对纤维素酶的酶解效果影响最大。与酸提法相比,酶法提取的石杉碱甲的提取率提高了40.3%。[结论]该方法简便快捷、提取率高,可用来提取蛇足石杉中石杉碱甲。 相似文献
16.
We compared patterns of acorn dispersal and predation by wood mice among four tree species (Quercus serrata, Quercus crispula, Castanea crenata, and Juglans mandshurica var. sieboldiana) that are abundant in cool temperate woodlands. We devised an acorn dispersal experiment using 400 magnet-inserted acorns and a magnetic locator in a 1.8-ha study plot, which spanned a cut-over area and an adjacent deciduous forest. Ten wire mesh baskets, each containing 40 acorns (10 acorns per species), were placed on the border between these two habitat types. About 13.0% (n = 52) of the total acorns remained in the baskets, while 77.3% (n = 309) were dispersed throughout the study plot and subsequently retrieved using the magnetic locator. Microhabitat, distance, and burial depth of transported acorns were significantly different among species. In the cut-over area, J. mandshurica var. sieboldiana acorns were dispersed under fallen trees or branches and near stumps, and were buried deeply in the soil. Dispersal distances of J. mandshurica var. sieboldiana acorns were significantly greater than those of Q. serrata acorns. The number and microhabitat of transported acorns significantly differed between habitat types. J. mandshurica var. sieboldiana acorns were dispersed in the cut-over area rather than in the forest. For all four species, the numbers of acorns delivered to fallen trees or branches, stumps, and crumbled soil with overhang under any vegetation type were greater in the cut-over area than in the forest. 相似文献
17.
为了给拟穴青蟹(Scylla paramamosain)苗种培育过程中饵料的合理投喂提供基础理论数据,采用投喂-饥饿和饥饿-投喂的处理方式对拟穴青蟹大眼幼体和Ⅰ期仔蟹分别开展营养储存饱和点实验(PRS)和不可恢复点实验(PNR),研究饥饿对大眼幼体和Ⅰ期仔蟹蜕皮和生长的影响。结果显示,大眼幼体的PRS实验中,投喂时间≤2 d时,大眼幼体的蜕皮率为0;投喂时间≥4 d时,大眼幼体的蜕皮率和发育时间与连续投喂组(F组)无显著性差异;但投喂4 d-饥饿组(F4S组)大眼幼体蜕皮后Ⅰ期仔蟹的增重率和个体大小均显著小于F组(P<0.05)。大眼幼体的PNR实验中,饥饿2 d时大眼幼体的存活率仅为(30.00±13.23)%。Ⅰ期仔蟹的PRS实验中,连续饥饿组(S组)Ⅰ期仔蟹的蜕皮率为0,而投喂2 d-饥饿组(F2S组)、投喂3 d-饥饿组(F3S组)和F组3组Ⅰ期仔蟹的蜕皮率均无显著性差异。投喂1 d-饥饿组(F1S组)和F2S组Ⅰ期仔蟹蜕皮后Ⅱ期仔蟹的增重率和个体大小均显著小于F组(P<0.05),且F1S组Ⅰ期仔蟹的发育时间显著延长(P<0.05)。Ⅰ期仔蟹的PNR实验中,除饥饿1 d-投喂组(S1F组)外,F组Ⅰ期仔蟹的蜕皮率显著高于其他处理组(P<0.05);各组Ⅰ期仔蟹蜕皮后Ⅱ期仔蟹的增重率与饥饿时间呈负相关,而发育时间却与饥饿时间呈正相关;饥饿时间≥2 d时,Ⅰ期仔蟹蜕皮后Ⅱ期仔蟹的个体大小明显变小。拟合分析结果显示,大眼幼体的PRS;值是3.57 d,Ⅰ期仔蟹的PRS;和PNR;值分别是0.90 d和2.01 d。研究结果表明,新蜕皮的大眼幼体必须给予充足的饵料才可确保高的存活率,大眼幼体投喂6 d后可以适当减少投喂量,短期饥饿对Ⅰ期仔蟹蜕壳和生长的影响相对较小,Ⅰ期仔蟹的耐饥饿能力强于大眼幼体。 相似文献
18.
Veronica R Alava Emilia T Quinitio Jennete B de Pedro Flora Mae P Priolo Zenith Gaye A Orozco & Mathieu Wille 《Aquaculture Research》2007,38(14):1468-1477
Wild‐caught and pond‐reared female mud crab Scylla serrata at different stages of ovarian maturation were collected from Samar and Capiz, Philippines. Crabs were categorized into five stages according to the external morphological and microscopic appearance of the most advanced oocytes. The ovaries, hepatopancreas, muscle and newly spawned eggs (NSE) were analysed for lipid class components and fatty acids. Total lipid was higher in pond‐reared than in wild‐caught crabs but increased with ovarian maturation in both groups. Ovarian lipid peaked at the fully mature stage, coinciding with a decline in hepatopancreatic and muscle lipids. Lipid levels declined significantly in spent females. The tissues contained elevated highly unsaturated fatty acids such as arachidonic (20:4n‐6), eicosapentaenoic (20:5n‐3) and docosahexaenoic (22:6n‐3) acids, but at higher levels in late maturing and fully mature ovaries and in NSE. The type of lipid class and fatty acid components in mature ovaries as well as in NSE are generally considered to be indicative of their importance in reproductive physiology and embryonic and larval development. 相似文献
19.
Wang?Gui-zhongEmail author Li?Shao-jing Zeng?Chao-shu Lin?Shu-jun Kong?Xiang-hui Ai?Chun-xiang Lin?Qiong-wu 《Aquaculture International》2005,13(5):459-468
This is an initial paper in a series of overviews of biological research and aquaculture development of the mud crab, Scylla serrata, in China. Results of experimental ecological studies on mud crabs are reported here. As a result of these experimental studies, results that are important for mud crab culture were also discovered and these include, methods to condition and manage broodstock, determination of ecological conditions that are suitable for embryonic development, and the influence of temperature, salinity, diet and larval density on development and survival of larvae. Results of this work will be useful in establishing a good method for artificial mass culture of larvae. 相似文献
20.