利用农杆菌介导法将反义waxy基因转入籼型杂交稻保持系-生物化学与分子生物学专业论文.docxVIP

摘 摘 要 水稻是世界主要粮食作物之一，然而目前我国种植的水稻品种尤其是籼稻品 种的品质比较差，其主要原因之一是直链淀粉含量偏高。因此，育种家们一直希 望通过适当降低直链淀粉含量达到改良稻米品质的目的。 随着分子生物学和基因工程的迅速发展，通过基因工程来改良稻米淀粉品质 成为可能。农杆菌介导的植物转基因方法由于具有操作简单、转化效率高、较少 的拷贝数及其整合机制相对简单等优点，被植物转基因工作者广泛推崇。本研究 用根癌农杆菌转化技术将反义Wclxfy基因导入籼稻保持系，以适当降低受体品种 的直链淀粉含量，从而改良稻米品质。主要结果如下： 1．通过对影响农杆菌侵染的诸多因素，如植物组织培养系统、愈伤组织生 理状态、农杆菌悬浮培养、农杆菌菌液浓度、共培养时间等参数的优化筛选，建 立了较好的农杆菌介导的D62B转基因体系。 2．获得了一批转反义WO．Xy基因的潮霉素抗性植株，PCR检测结果表明多 数抗性植株其选择标记基因和外源目的基因共整合到转基因水稻的基因组中。 3．对转基因T1代植株进行了遗传分析，D62B在潮霉素培养基上，多数生 长正常，表现对潮霉素抗性，且符合孟德尔单基因遗传规律。 4．对成熟种子直链淀粉含量的分析表明，所检测的转基因当代(To代)水 稻植株种子中的直链淀粉含量为20．3％，比未转化亲本植株种子的25．1％下降了 19．1％。 关键词：水稻；遗传转化；农杆菌；反义waxy基因；直链淀粉含量；稻米品质 ABSTRACTRice ABSTRACT Rice is one of the main food crops in the world．However,at present the quality of most rice varieties in china，especially indcia varieties，are poor relatively．A main reason of which is higher amylose content．So，rice breeders always expect to find a way to improve rice quality by decreasing mnylose content properly． With rapid development of molecular biology and genetic engineering，it has been possible to improve rice starch quality by genetic engineering．There are many advantages of Agrobacterium—mediated transformation，such as convenience in manipulation，hi曲transformation efficiency,low copy number of introduced genes and simple integration pattern，SO is widely utilized by plant transgene workers．In this paper，the antisense waxy gene has been transfered into indica maintainer lines through Agrobacterium-mediated transformation in order to reduce amylose content of the receptor varieties properly and then improve their rice quality,The major results were as follows： 1．By screening and optimizing such factors that may elt’ect Agrobacterium infection efficiency like tissue—culture system，physiological condition of calli， Agrobacterium suspension medium composition，Agrobacterium solution concentrati- on，co—cultivation duration and SO on，a high—efficiency system ofAgrobacterium—me— diated transformation for D62B was established． 2．Some tr