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1.
宁波出入境检验检疫局植检实验室在1份来自德国的松木质包装材料中截获一种伞滑刃线虫,经形态学观察、测量,以及ITS-RFLP图谱比对,鉴定为锥尾伞滑刃线虫(Bursaphelenchus conicaudatus Kanzaki,Tsuda & Futai,2000).该线虫属松材线虫组,与松材线虫(B.xylophilus)、拟松材线虫(B.mucronatus)、伪伞滑刃线虫(B.fraudulentus)、豆伞滑刃线虫(B.doui)等比较接近,但其雌虫尾较上述线虫更细长(c′=4.5),并且明显向腹面弯曲,尾尖突位于腹面,长约2~3μm;雄虫交和伞一般呈卵圆形或铲形.目前该线虫仅日本有报道,在德国尚无记载.作者对其形态特征作了描述,并与4个近似种作了比较.  相似文献   

2.
国内草莓上的3种新记录线虫   总被引:1,自引:0,他引:1  
2006~2007年在福建厦门草莓种植区进行草莓线虫种类调查,共鉴定出3目7科8属15种线虫.本文描述了其中的3个种:古氏滑刃线虫(Aphelenchoides goodeyi)、矮小盘旋线虫(Rotylenchus pumilus)和双尾滑刃线虫(Aphelenchoides bicaudatus).这3种线虫均为国内在草莓上首次报道,古氏滑刃线虫和矮小盘旋线虫为福建省的新记录种.  相似文献   

3.
自2001年7月至2002年12月在福建省各地共采集松树木质部样品256份,分离发现88份(34%)样品中含有伞真滑刃属Bursa phelenchus的线虫8种,本文先报道其中的4种:拟松材线虫Bursnphelenchus mucronatus Mamiya & Enda,1979、赫列尼克斯伞真滑刃线虫B.hellenicus Skarmoutsos G.et al.,1998、霍夫曼尼伞真滑刃线虫B.hofmanni Braasch,H.1998、奇异伞真滑刃线虫B.aberrans Fang,et al.,2002.  相似文献   

4.
以锥尾伞滑刃线虫(Bursaphelenchus conicaudatus)作为对照,在韩国不同地域和寄主中采集了15个松材线虫分离物、3 个拟松材线虫的分离物及5个未鉴定的该属的分离物,并对其进行了ITS 和 D2D3 rDNA序列分析。以单条雌线虫的DNA为模板,ITS 和 D2D3 区由PCR仪扩增并克隆其序列。结果表明,所有松材线虫的ITS 和 D2D3 区序列相同,没有种内变异。然而2个采自黑松和红松的拟松材线虫分离物的基因型分别是亚洲型和欧洲型。5个未鉴定线虫的数据表明,它们分别接近B. tusciae、B. lini、B. thailandae、B. doui和 B. hylobianum,该结果同时被形态学结果所支持。利用5种酶(Hinf I、Alu I、Msp I、Hae III、Rsa),PCR产物克隆并测序的数据也可以区分不同种和基因型。  相似文献   

5.
我国松树寄生线虫分类检索   总被引:1,自引:0,他引:1  
到目前为止,在我国松树体内已经发现有寄生线虫46个已知种和一些未定种。分属于3目9科17属。其中,滑刃目(Aphelenchida)线虫数量最多,包括滑刃科(Aphelenchidae)滑刃线虫属(Aphelenchus)、伞滑刃线虫属(Bursaphelenchus),外滑刃科(Ektaphelenchidae)外滑刃线虫属(Ektaphelenchoides)、外真滑刃线虫属(Ektaphelenchus)、隐滑刃线虫属(Crytaphelenchus),长尾科(Seinuridae)长尾线虫属(Seinura)等,总共40个已知种。垫刃目(Tylenchida)包括粒科(Anguinidae)茎线虫属(Ditylenchus),伪垫刃科(Nothotylenchidae)柱形垫刃线虫属(Cylindrotylenchus),纽带科(Hoplolaimidae)拟盘旋线虫属(Pararotylenchus),环科(Criconematidae)小环线虫属(Criconemella)、鞘线虫属(Hemicycliophora)等,共6个已知种。矛线目(Dorylaimida)仅有1个未定种。根据不同目、科、属、种的线虫主要形态鉴定特征,编制了46种松树寄生线虫分类检索表,从而有利于人们方便地鉴定和区分松树寄生线虫.  相似文献   

6.
为确定造成越南松林的枯死是否为松材线虫所为,对越南南部的林同省、中部的承天-顺化省、北部的广宁省的思茅松(Pinus kesiya Royle)、马尾松(P. massoniana Lamb.)和南亚松(P. merkusii jungh et de Vries)松树枯死现象及症状特点进行了调查,分别从52株枯死、濒死、健康松树木质部中抽取木质部样品,进行线虫分离,根据形态学特点确定这些松树体内寄生线虫的种类。调查发现松树在枯死过程中,树冠部分针叶失去光泽,逐渐褪绿变黄,进而褐红干枯,最后整个树冠变为褐色或红褐色,全株枯死,针叶下垂且当年不落; 随着病程的发展,松脂分泌逐渐减少,直至停止; 树干上有天牛产卵刻槽,死亡的松树上有天牛的羽化孔。在抽取的松树样品中分离鉴定到了泰国伞滑刃线虫(Bursaphelenchus thailandae)、悬臂伞滑刃线虫(B. gerberae)、中华伞滑刃线虫(B. sinensis)、树木伞滑刃线虫(B. silvestris)、托斯卡纳伞滑刃线虫(B. tusciae)、莱奴尔夫伞滑刃线虫(B. rainulfi)、云杉小蠹伞滑刃线虫(B. rufipennis)和伞滑刃属线虫未定种(B. sp.),调查中未发现重要检疫性病原松材线虫(B. xylophilus)。  相似文献   

7.
2006年5月,我校森林资源与环境学院叶建仁教授主持完成的“松材线虫SCAR标记与系列分子检测技术及试剂盒研制”通过了江苏省科技厅组织的科技成果鉴定。该项研究对松材线虫与拟松材线虫特异片段进行了系统筛选,共获得了7个松材线虫DNA特异片段与5个拟松材线虫DNA特异片段,为松材线虫与拟松材线虫的分子鉴定奠定了基础。首次将2个松材线虫与2个拟松材线虫的DNA特异片段成功转化为SCAR标记,丰富了松材线虫与拟松材线虫分子标记方法。首次采用SCAR标记方法成功构建了松材线虫检测试剂盒,PCR检测过程仅需2.2h。首次成功标记了一个可用于检测松材线虫的非放射性探针DlG—F2/R1。用该探针对线虫基因组DNA点杂交,松材线虫均表现有较强的杂交信号,而拟松材线虫、霍夫曼尼伞滑刃线虫、大核滑刃线虫、长尾属线虫等均无杂交信号。成功设计、合成了TaqMan探针与其配套的引物对F11/R11。  相似文献   

8.
马尾松包装木的树皮象伞真滑刃线虫新记录   总被引:7,自引:2,他引:5  
2002年从厦门口岸出口的71批货物木包装的83份样品中,多次检出多种伞真滑刃线虫(Bursaphelenchusspp.),有拟松材线虫(B.mucronatus)、奇异伞真滑刃线虫(B.aberrans),还从9份马尾松(Pinusmassoniana)木包装样品中检出另一种线虫,经形态学观察、测量,鉴定为树皮象伞真滑刃线虫(Bursaphelenchushylobianum(Korenchenko,1980)Hunt,1997).其特征是雄虫交合刺大而强壮,末端有帽状突起,髁突明显突起,靠腹面喙突钝圆,雌虫阴门处有小的阴门盖,尾部末端钝圆,明显向腹面弯曲.室内培养表明该线虫很容易在灰葡萄孢(Botrytiscinerea)培养物上继代繁殖.该线虫为中国的新记录种,马尾松为该线虫的寄主新记录.  相似文献   

9.
目前已经报道了伞滑刃属(Bursaphelenchus)内近百种线虫,其共同的形态特征是雄虫的尾部末端具有交合伞。在该属的分类中尚存在同物异名的问题。为此,基于其特征的复杂性,笔者提出根据线虫侧线的数目、尾乳突的排列、是否出现阴门盖、交合刺形状、外分泌孔及后部子宫分支的位置等特征,将该属分为7组,其中4条侧线组为xylophilus, okinawaensis, africanus, fungivorus, cocophilus, kevini和sexdentati;3条侧线组为eggersi, eremus, hofmanni,leoni;2条侧线组为abietinus和sinensis。73种列入上述分组中,24种因为缺乏形态学资料未能列入。交合刺不能用于分组。列入该分组的39种基于亚基核糖体DNA数据的分子树说明了该分组的合理性。另外,Parasitaphelenchinae, Aphelenchoidinae和Ektaphelenchinae亚科中28种线虫基于核糖体大亚基D1—D2区序列生成的分子树显示了它们在Aphelenchoididae科中的系统关系。  相似文献   

10.
植物寄生线虫造成的危害极大,开展捕食线虫真菌资源的研究是线虫生物防治的前提和基础.2006年至2007年间对云南西部云南松、华山松松树根际土中的捕食线虫真菌进行了调查,通过对分离到捕食线虫真菌土壤的地理位置、海拔的分析,结果表明:捕食线虫真菌在云南西部松树根际中广泛分布,从1000份样品中共分离、鉴定出捕食线虫真菌3个属(Arthrobotrys,Drechslerella,Dactylellina)21种和5个未产生捕食器的相关属Dactylella以及菌丝不分隔的捕食线虫真Stylopage属的1个种和Tridentaria属的1个种,其中2个为待定种.优势种为Arthrobotrys oligospora,Arthrobotrys musiformis,Arthrobotrys thaumasia,Dactylellina ellipsospora.在所分离到的捕食线虫真菌中,产生粘性菌网的菌种占优势.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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