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901.
水稻单叶独立转绿型黄化突变体grc2的鉴定与基因精细定位 总被引:4,自引:2,他引:2
转绿型叶色突变体是研究植物叶绿体分化与发育的基础材料。grc2是利用60Co-γ射线诱变籼型三系保持系T98B后获得的单叶独立转绿型黄化突变体。grc2植株上任一叶片刚抽出时为黄色,在生长10 d左右后变绿,具有单叶不依赖于植株特定发育阶段而独立转绿的特性。与野生型T98B相比,grc2黄化叶片的总叶绿素和叶绿素b含量显著降低,叶绿体滞留在黄化质体阶段,表明grc2可能在叶片早期发育中起关键作用。遗传分析表明,grc2受1对隐性核基因独立控制;利用源于grc2/Nipponbare的F2群体的960个突变单株,将grc2基因定位在STS标记S254与S258之间约31 kb的范围内,该区域含有5个未报道过的注释基因。这些结果为grc2的克隆及功能研究提供了重要信息。 相似文献
902.
Wang Tingkai 《保鲜与加工》1992,(1):108-113
This paper presents a new method of expert controller, which is gotten by means of combining the technique of expert system with predictor control. The method adopts the multimode control as well as on-line characteristic identification so that the controller could not only give full play to the expert' s experience but also reflect the accuracy of predictor algorithm in control process. The simulation shows that the method has strong Robustness and good adaptability even when the object varies or the load changes suddenly, or something unexpected happenes with the system. 相似文献
903.
Using semidifferentiable concept for set-valued mapping and defining strong semiconpact for set-valued mapping. The article studies the existence of positive fixed point for semidifferentiable and Upper semicontinuous set-valued 1-set-contractive mapping. 相似文献
904.
Architecture of Logistics system is the interior operation environment and business platform for Logistics companies, which is to steer to build special logistics system and tactics frame-saw to realize the company's objectives. Further more, characteristic and design principle of architecture are mentioned. There are 4 levels in this article to discuss the architecture of TPL system. Six elements contained in the architecture are mentioned: information platform, tech-equipment platform, knowledge platform, organization platform, business platform and functional platform, Furthermore, the mutual connection among which is analyzed as a whole. In conclusion, measure of the transfer from traditional storage and transportation to modern logistics is discussed. 相似文献
905.
In this paper, the factors influencing the foundation scheme of high-rise buildings are analyzed. In accordance with the complex hierarchical structure and the uncertainty of foundation scheme, a knowledge base of hierarchical structure is set up and an inexact reasoning is realized. Then, the expert system for high-rise buildings foundation scheme (TBFES) is built on the knowledge base with the expert system tool CLIPS. 相似文献
906.
A customer segmentation method based on dynamic SOM and RFM indicators is presented. Firstly, customer clusters is generated by DSOM clustering analysis. Secondly, customer loyalty, customer scale and customer credit are simulated by RFM behaviors of customer, and then customer clusters are identified. Finally, the value of customers can be decided according to the customer segmentation results, and enterprises are able to provide better different service levels to different customers. It provides customer strategies of enterprises with an effective support and decision-making. 相似文献
907.
Zhu Jisheng 《保鲜与加工》1988,(1)
In this paper, we obtained one implicit function theorm,which, in the inverse function cases, becomes to the necessary and sufficient condition for the mapping is a homeomorphism. 相似文献
908.
909.
Data-mining is a composite and multi - disciplinary technology newly developed. This paper will start by describing the fundamentals and basic methods of the technology followed by an overview of the latest development of its applications, problems and hurdles currently facing and the way forward and future work. 相似文献
910.
From the topological angle and byintroducing the definitions of continuous mapping, open mapping, closed mapping,homeomorphic mapping, submatroid and quotient matroids, under which the qualities of matroids are studied, and some equivalent condictions are obtained. Inadditional, whether the independent set,dependent set and circuit of matroids are held under these mappings is discussed. 相似文献