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1.
以抗生素抗性为选择标记的毛壳菌种间原生质体融合   总被引:1,自引:0,他引:1  
以抗生素抗性为选择标记进行角毛壳菌和球毛壳菌种间原生质体融合。角毛壳菌CH21-I-402菌株对潮霉素有抗性、对G418敏感,球毛壳菌CH08对潮霉素和G418敏感。根癌农杆菌介导的新霉素磷酸转移酶基因转化球毛壳菌,得到成功转化新霉素磷酸转移酶基因的球毛壳菌菌株,转化子对G418抗性提高3~4倍,对潮霉素仍然比较敏感。以耐潮霉素、不耐G418的角毛壳菌和不耐潮霉素、耐G418的球毛壳菌为出发菌株,以PEG6000为助融剂进行原生质体融合,用G418和潮霉素抗性进行筛选,获得再生菌株。经AFLP分析表明:再生菌株PF1、PF26为融合菌株,融合菌株菌落形态均与亲本存在明显差异。  相似文献   

2.
两种毛壳菌对几种植物病原菌的生防效果分析   总被引:1,自引:0,他引:1  
将角毛壳菌和球毛壳菌与立枯丝核菌等5种植物病原菌进行对峙试验,结果表明,球毛壳菌和角毛壳菌对几种病原菌的抑制作用明显.球毛壳菌主要通过竞争作用、重寄生作用抑制病原菌,角毛壳菌主要通过产生红色拮抗物质、竞争作用抑制病原菌的生长.  相似文献   

3.
将红色糖多孢菌(Saccharopolyspora erythraea)的染色体DNA用PsTi酶切后与载体PUWL201连接,转化变沿青链霉菌(S.lividans)TK23的原生质体。采用双重抗性筛选得到了9个转化子。分别抽提其中的质粒并再次转化原生质体,在含红霉素的平板上各筛选约200个转化子,其中3个在抗性板上生长良好,分别命名为PLP42、PLP1b和PLP44。对其中的PLP42酶切分析表明,其含有约3.0Kb的红色糖多孢菌(Saccharopolyspora erythraea)染色体DNA片段,它的载体部分发生了缺失。以PUC18为载体,将PLP42的1.7kb-KpnI片断克隆、测序、经与Genebank的ermE基因顺序比较,证实巳克隆了Saccharopolyspora erythraea的抗性基因。  相似文献   

4.
以β2-微管蛋白基因为定点整合位点,通过原生质体法将多菌灵抗性基因转化到哈茨木霉中,获得了具有多菌灵抗性的生物防治工程菌株.多菌灵抑制抗性转化子菌丝生长的ECso值达471.26μg/mL,比哈茨木霉原菌株提高1200倍以上;转化子对多菌灵的抗性具有遗传稳定性,且在无选择压力下菌丝生长速度及菌落形态与原菌株无显著差别;抑菌活性检测结果表明,3个转化子对立枯丝核菌均具有较强的抑菌活性,对菌丝生长的抑制率分别为87.5%、86.3%和85%.  相似文献   

5.
试验结果表明:贮鲜灵对柑桔青霉病的防治效果高达94.3%,霜霉灵,速克灵对青霉病的防效分别是28.1%和15.85;DT 杀菌剂,苯来特,甲基托布津,百菌灵,百菌清,杀毒矾,几乎没有防效;柑桔青霉病菌对苯并咪唑类的苯菌灵,硫脲基甲酸甲酯类的托布津已产生了抗药性,但对柑桔长效保鲜剂——贮鲜灵尚未产生抗药性,在柑桔保鲜贮藏中仍然可以继续使用。  相似文献   

6.
以质粒pUC13编码的β-内酰胺酶基因为外源基因,通过随机连接谷氨酸产生菌T_6-13染色体DNA片段后转化T_6-13原生质体,使其整合到染色体上,得以表达.在实验条件下,所测19株转化子的抗性都有很高的稳定性,其中10株能百分之百地保持抗性.经生物素标记的pUC13为探针的分子杂交实验证实抗性基因已整合到T_6-13菌染色体DNA上。  相似文献   

7.
试验结果表明:贮鲜灵对柑桔青霉病的防治效果高达94.3%,霜霉灵,速克灵对青霉病的防效分别是28.1%和15.8%;DT杀菌剂,苯来特,甲基托布津,百菌灵,百菌清,毒矾,几乎没有防效;柑桔青霉病菌对苯并咪唑类的苯菌灵,硫脲基甲酸甲酯类的托布津已产生了抗药性,但对柑桔长效保鲜剂-贮鲜灵尚未产生抗药性,在柑桔保2鲜贮藏中仍然可以继续使用。  相似文献   

8.
出发菌GR001通过形态观察、生理生化实验、16S rDNA同源性序列分析及部分特异性基因序列分析鉴定为解淀粉芽孢杆菌.以GR001为出发菌,通过化学诱变选育出一株遗传标记为腺嘌呤营养缺陷、6–巯基嘌呤抗性以及蛋氨酸亚砜抗性(Ade-+MSOr+6-MPr)的突变株GR600.以GR600为受体菌,采用原生质体转化法获得转化子GR607(Ade-+MSOr+6-MPr+kmr),鸟苷产量高达20.82,g/L.  相似文献   

9.
在构建的角毛壳菌(Chaetomium cupreum)菌丝体cDNA文库中获得丝切蛋白(Cofilin)的ESTs序列片段,为研究角毛壳菌的生物特性,提高其生物防治效果,以角毛壳菌总RNA反转录产物为模板进行PCR扩增,成功获得了Cofilin基因cDNA序列.生物信息学分析结果表明,该基因全长468bp,编码155个氨基酸,编码蛋白理论分子量17kD,等电点是4.99,α-螺旋和无规则卷曲是其主要的二级结构,为亲水性蛋白质.该蛋白有6个位点发生Ser磷酸化,4个位点发生Tyr磷酸化,有4个保守区,ClustalX分析说明该蛋白与柄孢霉(Podospora anserina)和球毛壳菌(C.g lobosum)亲缘关系较近.  相似文献   

10.
探究菌龄、稳渗剂种类、溶壁酶质量浓度、酶解温度、酶解时间和再生培养基对齿毛菌原生质体制备及再生的影响,并利用PEG介导原生质体转化. 结果表明: 以0.6mol·L-1甘露醇为稳渗剂,20mg·mL-1溶壁酶于30℃酶解48h菌龄的菌丝3h,所得原生质体形成数最多,为1×108个·mL-1;所得原生质体在0.8mol·L-1蔗糖为稳渗剂的2号培养基中再生率最高,为0.1%;PEG介导原生质体转化,经潮霉素B抗性平板筛选获得2个转化子. 实验建立的齿毛菌原生质体制备及转化体系,为其遗传操作及分子生物学研究奠定基础.  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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