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1.
以小麦杂24-2(Triticum aestivum,cv.24-2)花药来源的愈伤组织分离原生质体作受体;簇毛麦(Haynaldia villosa)幼胚来源的愈伤组织原生质体经220μW/cm^2紫外线照射30s作供体,作PEG法诱导融合,最后获得再生愈伤组织。以融合再生的4个最先长大的细胞系进行染色体,同工酶和RAPD分析。结果表明,这些细胞系均为体细胞杂种,RAPD技术可作为小麦体细胞杂种  相似文献   

2.
以小麦杂242(Triticumaestivum,cv.242)花药来源的愈伤组织分离原生质体作受体;簇毛麦(Haynaldiavilosa)幼胚来源的愈伤组织原生质体经220μW/cm2紫外线照射30s作供体,用PEG法诱导融合,最后获得再生愈伤组织.对融合再生的4个最先长大的细胞系进行染色体,同工酶和RAPD分析.结果表明,这些细胞系均为体细胞杂种,RAPD技术可作为小麦体细胞杂种早期鉴定的有效方法  相似文献   

3.
经狭叶柴胡悬浮细胞系分离的原生质体用强度为 2 60 μW /cm2 紫外线照射 0 ,1 ,2 ,3min后 ,与石防风原生质体在PEG诱导下融合 .对融合再生的 56个单细胞克隆进行杂种形态学、染色体、同功酶分析表明 ,其中的 34个为体细胞杂种细胞系 .5个杂种愈伤组织 (不对称融合产物 )在培养 1 2个月时再生出完整小植株 .  相似文献   

4.
药用植物石防风与柴胡不对称体细胞杂交的初步研究   总被引:7,自引:0,他引:7  
经狭叶柴胡悬浮细胞系分离的原生质体用强度为260μW/cm^2紫外线照射0,1,2,3min后,与石防风原生质体在PEG诱导下融合,对融合再生的56个单细胞克隆进行杂种形态学、染色体、同功酶分析表明,其中中的34个为体细胞杂种细胞系。5个杂种愈伤组织(不对称融合产物)在培养12个月时再生出完整小植株。  相似文献   

5.
普通小麦与玉米的体细胞杂交再生完整植株   总被引:3,自引:2,他引:3  
从小麦济南177制备得到两种原生质体,一种来源于具有一定分化能力的愈伤组织但其分裂能力较低;一种来源于生长迅速的悬浮细胞但不能分化,将二种原生质体混合,共同作为受体与经过紫外线(UV)照射的玉米(Zea mays L)原生质体在PEG诱导下融合,培养后获得再生克隆并进一步分化为植株,而它们单独与玉米原生质体融合均不能再生植株,通过染色体、同工酶及5SrDNA分析及生长习性分析证明再生植株均为体细胞杂种。  相似文献   

6.
【目的】通过对比研究不同种杨树的铅(Pb)抗性和Pb积累能力,筛选具有修复Pb污染土壤潜力的杨树树种。【方法】选取7种速生杨树,用8 mmol/L Pb处理6周,分析7种杨树Pb抗性和积累能力。【结果】Pb胁迫导致7种杨树净光合速率、气孔导度和蒸腾速率降低,抑制了7种杨树的高生长和径向生长,其中欧洲黑杨、群众杨和青杨的光合和生长对Pb胁迫较敏感,美洲黑杨敏感性较低。Pb胁迫导致7种杨树生物量显著降低,其中欧美杨根生物量降低最多(50.31%),欧洲黑杨(31.99%)和群众杨(22.26%)木材生物量降低最显著,欧美杨(12.67%)和群众杨(19.54%)皮生物量降低最显著,灰杨叶生物量降低最多(35.44%)。7种杨树的总生物量在Pb胁迫下出现明显降低,其中灰杨降幅最大(29.03%),欧洲黑杨降幅最小(12.02%)。相应地,7种杨树Pb抗性指数大小顺序依次为:欧洲黑杨(88.09%)>银腺杨(82.98%)≈美洲黑杨(80.70%)>欧美杨(79.86%)>青杨(76.79%)>群众杨(72.78%)≈灰杨(70.35%)。7种杨树吸收和转运Pb的能力存在较大差异。美洲黑杨根中的Pb含量最高,达2 906.10 mg/kg;灰杨木材、皮和叶中的Pb含量较高,分别达46.55、44.39和325.90 mg/kg。美洲黑杨根和整株Pb积累量最大,分别为4.20和5.06 mg/株;灰杨地上部分Pb积累量最大,为1.21 mg/株。美洲黑杨的根富集系数最大,达6.70;灰杨地上部分富集系数最大,为0.43。灰杨的Pb转运系数显著高于其他杨树,达0.16;欧洲黑杨的转运系数最低,仅为0.02。【结论】7种杨树的Pb抗性和Pb积累能力存在明显差异,其中欧洲黑杨Pb抗性最强、美洲黑杨根吸收Pb的能力最强,可能在Pb污染土壤的植物固定和生态恢复方面具有较大潜力;灰杨转运Pb能力最强,地上部分Pb积累能力最强,可能在Pb污染土壤的植物提取方面具有较大潜力。  相似文献   

7.
埃斯基红豆草原生质体培养直接形成体细胞胚与再生植株   总被引:2,自引:0,他引:2  
埃斯基红豆草花茎愈伤组织的原生质体在修改的KM8P和V-KM液体培养其中均能高频率地分裂和形成克隆,其分裂率为71.4%-76.19%,在KM8P培养其中,原生质体经不等分裂可以直接形成体细胞胚,在V-KM培养其中形成的小愈伤组织培养也有体细胞胚的分化。  相似文献   

8.
对宁夏枸杞愈伤组织体细胞胚发生的影响因素进行分析,结果表明,宁夏枸杞根外植体的年龄及其生理状态能影响胚性愈伤组织的形成和体细胞胚发生;4℃低温处理两周能明显促进愈伤组织形成体细胞胚,同时也能增加愈伤组织内源多胺的含量;添加Ag+有利于愈伤组织的体细胞胚发生,适当增加Ca2+浓度也有利于愈伤组织的生长及其体细胞胚发生;Eu3+的添加能明显促进愈伤组织生长,而低浓度的Ce2+、Eu3+作用有利于愈伤组织体细胞胚发生.  相似文献   

9.
就5种碳源对柑橘愈伤组织生长及其体细胞胚胎发生能力的影响进行了研究.结果表明:蔗糖和葡萄糖有利于柑橘愈伤组织生长,乳塘和甘油对柑橘愈伤组织的生长影响较小,而可溶性淀粉不利于柑橘愈伤组织的生长.不同碳源对具有体细胞胚胎发生能力的柑橘愈伤组织的影响各异,但对于失去再生能力的柑橘愈伤组织而言,不同碳源对其体细胞胚胎发生不起作用.  相似文献   

10.
紫锥菊愈伤组织原生质体分离方法初探   总被引:3,自引:0,他引:3  
紫锥菊提取物属于目前国际上流行的草本植物药,其主要运用于增强免疫力等方面.以加拿大狭叶紫锥菊愈伤组织为材料,研究影响其原生质体分离的因素,结果表明选用浅黄绿色、质地均匀且呈疏松颗粒状的紫锥菊愈伤组织易游离出原生质体;采用纤维素酶浓度为2.0%,果胶酶浓度为1.0%,半纤维素酶浓度为0.5%,甘露醇浓度为0.7 mol·L-1的酶液配方酶解时间为8 h时,原生质体的产量为每克鲜重含50.0×104个.由此归纳出一套完整的愈伤组织诱导,组织培养,原生质体分离纯化,原生质体鉴定及计数的方法.  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
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   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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