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1.
苜蓿组织培养体细胞胚发生的细胞学观察   总被引:14,自引:0,他引:14  
苜蓿无菌苗下胚轴在含2mg/L2.4-D和0.5mg/L6BA的MS培养其中诱导出愈伤组织,愈伤组织在含有3mg/LNAA和1.5mg/LKT的SH培养基中形胚性愈伤组织,并伴随有体细胞胚的发生。  相似文献   

2.
茴香原生质体培养研究   总被引:1,自引:0,他引:1  
以茴香(FoeniculumvulgareL.)幼苗茎切段在MS附近2,4-D1mg/L、6-BA0.5mg/L的培养基上诱导产生愈伤组织,经4~5次继代后形成胚性愈伤组织。将胚性愈伤组织转至MS+NAA1mg/L+2,4-D0.5mg/L+6-BA0.25mg/L的液体培养基中培养,形成胚性细胞悬浮系。悬浮细胞在含有1.5%纤维素酶、1%果胶酶、0.5%蜗牛酶的混合酶液中酶解得到大量的原生质体,原生质体用修改的KM8P培养基中做液体浅层培养。2天后细胞发生一裂,两个月后形成0.5~1mm大小的小愈伤组织,转入含琼脂糖的固体培养基中3周后形成2~3mm的愈伤组织  相似文献   

3.
以红三叶(Trifoliumpratense)野生品种巴东红三叶的叶片为外植体,在MB-1至MB-9的固体培养基上诱导愈伤组织,筛选出最佳培养基是MB-9培养基.以白三叶(Trifoliumrepense)裁培品种“路易斯安娜”和“Huca”的叶片为外植体,接种在MB-9固体培养基上诱导愈伤组织.愈伤组织形成以后,均在MB-9固体培养上继代培养3~4次后,获得胚性愈伤组织,然后转至MB+3mg/L2,4-D+07mg/LBA+02mg/LNAA+2mg/L甘氨酸+500mg/LCH+3%蔗糖的液体培养基中,经强化培养,2个月后,获得胚性细胞悬浮系.实验结果表明,缩短换液时间,即每隔3~4d换一次,可加快胚性细胞悬浮系的建立.  相似文献   

4.
用虎眼万年青鳞片外植体在MS培养基上实现了不同形态发生途径的激素调控。结果显示,生长素和细胞分裂素两类激素的不同组合和浓度搭配都是影响形态发生途径的关键因素,甚至前者更为重要。就最佳激素组合和浓度搭配而言,NAA0.5mg/L+BA0.5mg/L和NAA0.5mg/L+KT0.5mg/L分别诱导体细胞胚和不定芽直接发生;2,4-D4.0mg/L+BA1.0mg/L诱导愈伤组织;2,4-D0.1mg  相似文献   

5.
大叶相思体细胞胚胎发生的初步研究   总被引:4,自引:0,他引:4  
以种子萌发的无菌苗下胚轴为外植体,在B5+2,4-D(10-4mol/L)+BA(10-6mol/L)+CH0.5g/L的固体培养基上培养4周,获得了胚性愈伤组织.该愈伤组织经B5+2.4-D(10-4mol/L)的液体培养基7d的诱导在B5+L-谷氨酰胺(200mg/L)+CH(0.5g/L)的液体培养基上培养14d产生了球形胚.球形胚具有明显的两极,但只是根端发育,苗端并没有发育  相似文献   

6.
荞麦组织培养中的植株再生   总被引:1,自引:0,他引:1  
用荞麦无菌苗的幼茎和幼叶作外植体分别接种在MS补加不同激素组合的培养基上培养获得再生植株。实验结果表明,适宜诱导愈伤组织的激素组合为2.4-D4.0mg/L+KT0.2mg/L,适宜愈伤组织生长的激素组合为2.4-D1.0mg/L+KT1.0mg/L。诱导芽的较适宜的组合为6-BA3.0mg/L+IAA0.1mg/L,不定芽接种到含MS+IBA2.0mg/L+KT0.1mg/L的MS培养基上就能生  相似文献   

7.
莜麦组织培养及再生植株   总被引:3,自引:0,他引:3  
以莜麦(Avenanuda)成熟种子为材料,研究了培养基成分对愈伤组织的诱导、分化和继代保持的影响。通过对MS为基本培养基附加2,4-D、6-BA、KT、ZT等成分的各种培养基上诱导产生的愈伤组织观察比较,发现在2,4-D浓度为2mg/L时,诱导产生的愈伤组织量最多,随着2,4-D浓度降低,愈伤组织形成的量也减少;在2,4-D1mg/L、KT0.25mg/L的培养基中愈伤组织能分化出芽,产生大量苗,进而再生植株。实验结果表明,在继代培养基中加入一定量的ABA和ZT,能有效地促使褐化的愈伤组织恢复正常,使之保持良好的生长状态和分化能力。  相似文献   

8.
芝麻下胚轴愈伤组织的形成和器官发生   总被引:4,自引:0,他引:4  
本文研究了五种植物激素对芝麻下胚轴愈伤组织的形成和器官发生的影响.研究表明:(1)2.4-D或NAA(1mg/L)+BA或KT(0.smg/L),2.4-D(0.5-1mg/L)和NAA(05-1mg/L)对愈伤组织的诱导率最高;(2)BA或KT(0.5-1mg/L)可促进下胚轴芽丛的形成(3)NAA(0.5-1mg/L)、IAA(0.5-1mg/L)和KT(0.5-1mg/L)对下胚轴根的形成最有利.  相似文献   

9.
以大花君子兰(clivia miniata) 瘤状结构的胚性愈伤组织为单细胞培养来源,在附加2 mg/LKT、1mg/L2 ,4 —D 及3 % 蔗糖的MS基本培养基上培养,诱导出的愈伤组织经同一诱导培养基长期继代培养后形成幼苗,将较大的幼苗转入状苗生根培养基( 附加0-5 mg/LKT 和0-1mg/LNAA的1/2 MS培养基) 上继代培养形成再生绿色植株。绿苗再生频率随继代时间的延长而提高。  相似文献   

10.
蛇床幼茎外植体在MS+2,4-D2mg/l+KT0.2mg/l培养基上形成淡黄绿色松软状愈伤组织。愈伤组织在转入培养基MS+NAA0.2mg/l+2T0.8ng/l以后分化出不定芽,在1/2MS+IAA2mg/l培养基中可产生不定根,进而发育成为完整植株。愈伤组织在MS+2,4-D0.2mg/l+ZTZT0.4mg/l培养基中继代3~4次以后,再转入MS+NAA0.2mg/l+ZT0.8ml/l培养基中继代1~2次,形成了大量胚状体。胚状体经过球形胚、心形胚、鱼雷胚和子叶胚最终发育成再生植株。器官发生和体细胞胚胎发生这两种形态发生方式在发生顺序、形态特征和所需激素条件等方面都是不同的。  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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