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1.
长白山林区棕背(鼠平)秋季种群数量的预测   总被引:3,自引:1,他引:3  
棕背 (Clethrionomysrufocanus)为我国北方林区主要森林害鼠之一 ,对林木的危害程度与棕背数量有直接关系[1] ,危害时间主要在秋末至来年初春。在林木鼠害防治中 ,将棕背秋季种群数量提前做出预测预报 ,对采取预防措施具有重要意义。关于棕背种群数量动态的研究已有一些报道[1~ 5] ,棕背危害伊春林区的预测也有报道[1,6] 。作者根据多年在长白山林区调查鼠害的结果 ,提出适合该林区的具体预测方法 ,现将研究结果报道如下。1 研究地点与方法棕背在长白山林区的数量分布有明显的地带性[5,7] ,研究地点选…  相似文献   

2.
中国棕背(鼠平)亚种分化的研究(啮齿目:仓鼠科:田鼠亚科)   总被引:1,自引:0,他引:1  
本文对中国山西、河北、内蒙古南部、大、小兴安岭、长白山及新疆等地区的215号棕背(鼠平)(Clethrionomys rufocanus)标本的外形和头骨的形态进行了亚种分化研究,认为分布于山西、河北、内蒙古南部棕背(鼠平)的亚种为Clethrionomys rufocanus shanseius(Thomas);大、小兴安岭及新疆地区的亚种为Cl.r.irkutensis(Ognev);而将分布于长白山地区的亚种定为一新亚种——棕背(鼠平)长白山亚种(Clethrionomys rufocanus changbaishanensis)。  相似文献   

3.
Using partial sequences of mtDNA control region,we sought genetic diversity,population genetic structure and subspecies classification in 5 populations of Myodes rufocanus from Northeast China and Hokkaido,Japan. After sequencing a 616 bp segment of control region,we detected 45 haplotypes based on 57 variable sites among 55 individuals. Our results revealed that high-level haplotype diversity and slightly less nucleotide diversity occurred in these populations. AMOVA analysis showed that high-level genetic differentiation happened between populations due to 64.70% genetic diversity and Fst ranging from 0. 240 to 0. 814. In a phylogenetic analysis,the haplotypes from Northeast China split into two groups:Daxing’anling-Xiaoxing’anling-Wandashan and Hailin-Dahailin. This suggested that we can separate the populations from Northeast China into two subspecies,M . r. irkutensis and M. r. Changbaishanensis respectively corresponding with the former and latter areas.  相似文献   

4.
5.
棕背(鼠平)(Clethrionomys rufocanus)与红背(鼠平)(Clethrionomys rutitus)是吉林省林木主要害鼠,本文应用数量化方法,分析野外调查数据,阐明它们对栖息地选择的生物学特性,为森林鼠害防治工作提供依据。 1.研究方法 1983年9月15日至10月15日,吉林省林业厅在全省43个县同时对森林害鼠的种类、分布密度和危害进行调查,共布41376铗日,捕鼠2271只。本文选择东部山区樟子松人工林31块、红松人工林50块、落叶松人工林78块、人工针叶混交林15块、天然次生林42块样地,对棕背(鼠平)与红背(鼠平)的铗日捕获  相似文献   

6.
三种啮齿动物的消化道形态特征   总被引:8,自引:4,他引:8       下载免费PDF全文
对棕背(Clethrionomys rufocanus)、林姬鼠(Apodemus speciosus)和黑线姬鼠(A.agrarius)夏季的消化道形态进行了比较。3种啮齿动物总消化道的长度及重量(含内容物重和总干组织重),各器官的长度,胃、小肠和盲肠等长度,小肠和盲肠含内容物重,盲肠和大肠去内容物重,小肠、盲肠和大肠总干组织重等均存在明显的种间差异。以植物为食的棕背的总消化道、小肠、盲肠和大肠的长度或重量明显长于或重于其他两种鼠类。后肠可作为衡量草食性动物食物质量的指标。3种啮齿动物可通过消化道形态改变以适应不同的食性。  相似文献   

7.
三种鼠针毛表面超微结构的比较研究   总被引:4,自引:0,他引:4  
利用扫描电镜技术对棕背(鼠平)Clethrionomys rufocanus、大林姬鼠Apodemus sylvatics和花鼠Eutaraias sibiricus 3种森林害鼠针毛的表面结构进行观察.研究结果认为:3种鼠针毛在鳞片类型、游离缘平滑度、高度、密度等因素上存在一定的差异,其中棕背(鼠平)和大林姬鼠差异不显著,而花鼠与其它两种鼠差异显著,在鼠的分类上具有一定的参考意义.  相似文献   

8.
采用硅胶、MCI Gel、Sephadex LH-20、ODS等柱色谱,结合半制备液相色谱,从红棕杜鹃(原变种)叶乙醇提取物的石油醚部位分离纯化得到一对双键位置异构的杜鹃色烯杂萜化合物:isoconfluentin(1)和(+)-confluentin(2),其中化合物1为新化合物。运用现代波谱学方法(1D和2D NMR、UV、IR、MS等)对所分离得到的化合物进行了结构鉴定,而且采用色烷/色烯螺旋规则(chromane/chromene helicity rule)鉴定它们的绝对构型均为2 S构型。测定化合物1和2的体外凝血酶原时间,发现它们均具有有效的抗凝血作用。  相似文献   

9.
2008 年2-6 月, 在广东海丰鸟类自然保护区对棕背伯劳棕色型(normal morph)、黑色型(dark morph)及其不同杂交型的巢址选择及巢的生态测量值进行了比较。结果如下: 1)野外观察发现棕背伯劳不同色型间未有生殖隔离; 2)对59巢15 个巢址因子进行主成分分析表明, 巢址选择均主要受5 个主成分的影响(5 个主成分中, 相对系数绝对值最高的变量依次是: 巢位高、水源距离、巢下方郁闭度、巢枝分叉级数和巢树隐蔽度), 累计贡献率达70.18%。三种交配型(黑色型-黑色型, 黑色型-棕色型和棕色型-棕色型)巢址选择的主要影响因子皆无显著性差异(P > 0.05)。3)不同交配型在巢材选择上取材均较为广泛, 但差异不显著, 巢的生态测量值亦无显著差异(P > 0.05)。结论认为, 棕背伯劳不同色型在巢址生态位尺度上未出现明显分化。  相似文献   

10.
棕背伯劳两种色型繁殖特征的比较   总被引:3,自引:0,他引:3       下载免费PDF全文
棕背伯劳(Lanius schach)具羽色多态现象,其中黑色型是否为独立种曾存在着争议。为此,于2008年2—6月在广东海丰地区对两色型(棕色型和黑色型)的繁殖生态进行对比研究,以探讨黑色型的分类地位。结果表明:1) 两色型伯劳窝卵数、卵的度量值及发育上皆无显著差异(P>0.05);2) 两色型雏鸟在15日龄前的体长、翼长及体重等生长曲线均符合Logistic方程,除尾长渐进值参数呈显著差异(P<0.05)外,其他均无显著性差异(P>0.05);3) 据14日龄的雏鸟测量值表明,两色型在身体外部器官各项生长量度均无显著性差异(P>0.05);4) 易卵易雏实验表明,在孵卵和育雏过程中,两种色型棕背伯劳亲鸟之间皆可相互接受对方同一时期的卵和雏鸟,但不接受对方的异期卵;5)易雏后亲子和义子索食、站立、理羽、休息等行为差异不明显。因此认为黑伯劳只是棕背伯劳的一个色型而非独立种。  相似文献   

11.
    
Molecular tools have diverse applications in marine ecology. In microbial systems, DNA sequences of rRNA and other genes have identified a variety of novel lineages of bacteria inhabiting marine environments that have resisted traditional culture methods. However, relatively few natural populations have been characterized due to the rather labor-intensive methodologies employed. Recent technological developments such as in situ PCR and flow cytometry promise to greatly enhance the speed at which microbial taxa can be identified and enumerated in field collected water and substrate samples; such advances will allow future work to employ the spatial and temporal field sampling required to monitor the impact of natural and anthropogenic changes in the environment. This approach also holds promise for examining physiological status of field collected cells, garnering information on such elusive parameters as growth rates and the extent of nutrient limitation under natural conditions. Studies of macrobiota have similarly benefited from the use of molecular approaches to species identification. This has been particularly true with regard to distinguishing among larval forms of closely related taxa which are nearly identical morphologically. Genetic variation within species assayed by molecular tools has been useful in examining the stability of populations through time and in assessing patterns of recruitment to geographically separated populations. Enhanced understanding of these ecological problems will also require intensive spatial and temporal monitoring of both larval and adult populations. Often, the newer techniques based on DNA sequence variation have practical advantages over allozyme techniques: e.g., PCR allows assay of minute quantities of DNA that may come from ethanol preserved samples. However, when ample allozyme variation exists to address a given issue, these older techniques may be favored on a variety of criteria, including speed and cost. Hence, choice of methodology should be based on the expected efficiency of a given approach to a specific problem rather than the apparent sophistication of the method itself.  相似文献   

12.
    
Decline and long-term depression of mean densities of the grey-sided vole (Myodes rufocanus) and the field vole (Microtus agrestis) have occurred in managed forest landscapes of Sweden since the 1970s. Generally poor over-winter survival during a period with mild winters suggested a common climatic driver, but other explanations exist. Here we explore the response of the grey-sided vole, preferring forested habitats, and the field vole, preferring open habitats, to clear-cutting of old forest in Sweden. The cumulated impact from long-term clear-cutting explained local disappearances of the grey-sided vole. Maintained connectivity of old forest to stone fields was important for local population survival, since no such populations disappeared. For the grey-sided vole, it is probable that climate is not the dominating driver due to different timing of the decline in our study area. Instead, habitat loss is concluded as being a potential cause of the decline in mean density and depression of grey-sided vole densities. The long-lasting depression of field vole densities, despite favourable landscape changes, suggests action of another strong driver. A recent field vole recovery, essentially back to pre-decline densities and distribution, coincided with favourable winter/snow conditions, suggesting a climatic driver in this case.  相似文献   

13.
通过对稻属(Oryza L.)及其近缘种等禾本科(Gramineae)植物叶绿体psbA-trnH基因进行扩增和测序,分析其系统进化关系及序列差异,并设计鉴定斑点野生稻(O.punctata)的特异分子标记。序列分析的结果表明,栽培稻材料间psbA-trnH基因序列没有或很少存在碱基差异,野生稻相对变异丰富,其中靠近3′端下游序列碱基变异较为丰富,5′端相对保守。根据斑点野生稻psbA-trnH基因序列的特异位点设计的引物,扩增的目的片段ptBD118长118bp,退火温度在62℃时特异性最佳。在条码基因差异位点分析的基础上,开发的特异分子标记用于物种的快速鉴定,为珍贵物种的口岸鉴定提供了检测方法。  相似文献   

14.
    
We studied the seasonal variation of adaptive humoral immunity (AHI) in northern red‐backed vole (Clethrionomys rutilus Pallas, 1779, RBV) and gray‐sided vole (C. rufocanus Sundevall, 1846, GSV) in Tomsk region of Western Siberia. Immunoresponsiveness (IR) to sheep red blood cells was assessed by the number of antibody‐producing cells in the spleen. The use of a generalized linear model to analyze the effects of species, sex, year of research, and season of withdrawal of individuals from nature on IR showed a significant effect of species identity, season of animal capture, and the interaction of species with season. The RBV demonstrated higher immune responses during a year, and both species had higher IR in winter. Suppression of IR in spring was greater, started earlier, and lasted longer (March–May) in GSV. In RBV, immunosuppression was restricted to April. The significant negative within year correlations of IR with body mass and masses of reproductive organs in GSV indicated a trade‐off between AHI and growth and reproduction processes. A probable explanation for the difference between species in the seasonal variation of AHI may be related to the difference in tropho‐energetic requirements of each vole species. GSV is a predominantly herbivorous rodent and its thermoregulation seems less efficient than of RBV. The deeper spring immunosuppression in GSV may explain in part its higher mortality during the season of colds.  相似文献   

15.
16.
为区分黄颡鱼(Pelteobagrus fulvidraco Richardson)、瓦氏黄颡鱼(Pelteobagrus vachelli Richardson)及其杂交种,前期研究构建了一个YY超雄黄颡鱼的BAC文库并筛选到了一个包含性别连锁标记Pf62-Y的BAC克隆。研究对该BAC克隆进行测序并鉴定到了一个新基因Inad-like,而且Inad-like的外显子序列在X和Y染色体上基本一致。通过黄颡鱼Inad-like的外显子序列及序列的保守性我们设计引物在瓦氏黄颡鱼中扩增获得了其部分内含子序列。通过内含子序列比对,发现瓦氏黄颡鱼比黄颡鱼少了一个DNA片段。基于黄颡鱼和瓦氏黄颡鱼的显著遗传差异,设计了一对引物,该引物在黄颡鱼和瓦氏黄颡鱼基因组中分别扩增出1908和1178 bp DNA片段,而且在杂交黄颡鱼中同时扩增出这两个DNA片段。总之,这个新的遗传标记提供了一种稳定、高效识别黄颡鱼及其与瓦氏黄颡鱼杂交种的方法。  相似文献   

17.
玉米细菌性枯萎病及其病原菌的检测技术   总被引:3,自引:0,他引:3  
玉米细菌性枯萎病是影响玉米生产的重要病害 ,该病害通过带菌的种子进行远距离传播 ,对该病菌的检测成为防止和控制该病害的重要手段。介绍现有的检测该病菌的各种方法 ,即黑色素选择培养法、double sandwichELISA以及RAPD PCR ,LCR PCR ,Nested PCR ,multiplePCR和荧光实时PCR等分子生物学检测方法 ,并对这些方法的特性进行比较和探讨。  相似文献   

18.
Alexander Rosenberg recently claimed (1997) that developmental biology is currently being reduced to molecular biology. cite several concrete biological examples that are intended to impugn Rosenberg's claim. I first argue that although Laubichler and Wagner's examples would refute a very strong reductionism, a more moderate reductionism would escape their attacks. Next, taking my cue from the antireductionist's perennial stress on the importance of spatial organization, I describe one form an empirical finding that refutes this moderate reductionism would take. Finally, I point out an actual example, anterior-posterior axis determination in the chick, that challenges the reductionist's belief that all developmental regularities can be explained by molecular biology. In short, I argue that Rosenberg's position can be saved from Laubichler and Wagner's criticisms and putative counter-examples, but it would not survive a different kind of counter-example.  相似文献   

19.
植物螯合肽及其在重金属耐性中的作用   总被引:26,自引:0,他引:26  
综述植物螯合肽的生物合成及其在重金属耐性中的作用.有毒重金属在土壤中的积累不仅影响作物的生长和产量形成,而且严重威胁农产品的安全性.植物对重金属的耐性和积累在种间和基因型之间存在着很大的差异,在重金属胁迫条件下植物螯合肽(PC)的合成是植物对胁迫的一种适应性反应,耐性基因型合成较多的PC谷胱苷肽是合成PC的前体,PC可与重金属螯合,并进一步转运至液泡贮存,使细胞质的重金属浓度降低,从而达到解毒效果.重金属诱导植物合成PC的遗传机理和生化途径有赖于分子生物学的深入研究,cD-敏感型拟南芥突变体Cad1-1(缺失GSH)和Cad2-1(缺失PC合成诱导酶)的分离及相关研究,佐证了PC在Cd-解毒中起关键作用.对PC在重金属污染土壤或水体的植物修复和农作物安全生产中的意义进行了讨论.  相似文献   

20.
在放线菌分类学研究中,最初是根据形态特征、生理生化特征等表观分类学特征进行研究。随着分子生物学的飞速发展,放线菌的分类鉴定亦从传统的表型分类进入到各种基因型分类水平。分子分类在放线菌分类研究中起到越来越重要的作用,目前放线菌的分子分类研究主要包括:G Cmol%测定、DNA杂交、核酸结构分析以及DNA指纹图谱分析等方面。  相似文献   

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