水稻转基因技术的现状及在育种上的应用

近十几年来,随着分子生物学的飞速发展,人类对植物基因的结构、功能和表达有了较为清晰的了解,分子生物学对作物育种的促进作用越来越明显。与植物基因组的研究、ＲＦＬＰ和ＰＣＲ等辅助选择手段相比较,转基因技术以其把外源基因主动导入、定向改造植物的优点日益为世人所瞩目转基因技术使基因可以在植物、动物、微生物之间相互转移,克服了物种间的隔离,已成为一种新的育种手段。     

第二届植物分子育种国际学术研讨会

现代农业已经发展到了“分子农业”时代，基因工程、转基因技术等分子生物学手段广泛应用于植物的遗传育种，基因组学的研究成为植物基因资源发掘的基本科学平台，分子育种成为植物育种的最主要手段之一。为加强与国际植物分子育种领域的合作与交流，推动应用基因与组学植物分子育种科学的发展。     

第二届植物分子育种国际学术研讨会2007年3月23-27日在海南省三亚市召开

现代农业已经发展到了“分子农业”时代,基因工程、转基因技术等分子生物学手段广泛应用于植物的遗传育种,基因组学的研究成为植物基因资源发掘的基本科学平台,分子育种成为植物育种的最主要手段之一。为加强与国际植物分子育种领域的合作与交流,推动应用基因与组学植物分子育种科学的发展,TheGenerationChallengeProgramme(全球挑战计划)、国际水稻研究所、海南省科学技术协会、中国农业科学院、海南省热带农业资源开发利用研究所等单位发起,定于2007     

农业生物技术发展及我国的策略(摘要)

随着八十年代初转基因技术的出现及逐步发展,生物技术进入了分子水平发展时代。1985年世界上第一株抗病毒的转基因植物的成功实验标志着农业生产从此有了一种崭新的育种手段,这种分子生物学育种手段为培育出高产、稳产、优质的作物品种提供了一条可能的途径。在 这短短的十几年时间中,植物基因工程进展迅速,目前世界上已有一百多种转基因植物,有的已进入中、小规模甚至大规模的大田实验。     

第二届植物分子育种国际学术研讨会——2007年3月23～27日在海南省三亚市召开

现代农业已经发展到了“分子农业”时代,基因工程、转基因技术等分子生物学手段广泛应用于植物的遗传育种,基因组学的研究成为植物基因资源发掘的基本科学平台,分子育种成为植物育种的最主要手段之一。为加强与国际植物分子育种领域的合作与交流,推动应用基因与组学植物分子育种科学的发展。The Generation Challenge Programme（全球挑战计划）、国际水稻研究所、海南省科学技术协会、中国农业科学院、海南省热带农业资源开发利用研究所等单位发起,定于2007年3月23～27日在海南省三亚市举办“第二届植物分子育种国际学术研讨会”。     

第二届植物分子育种国际学术研讨会

现代农业已经发展到了“分子农业”时代,基因工程、转基因技术等分子生物学手段广泛应用于植物的遗传育种,基因组学的研究成为植物基因资源发掘的基本科学平台,分子育种成为植物育种的最主要手段之一。为加强与国际植物分子育种领域的合作与交流,推动应用基因组学与植物分子育种科学的发展,The Generation Challenge Programme（全球挑战计划）、中国农学会、中国农业科学院等单位发起并定于2007年3月23-27日在海南省三亚市举办“第二届植物分子育种国际学术研讨会”。     

第二届植物分子育种国际学术研讨会2007年3月23-27日在海南省三亚市召开

现代农业已经发展到了“分子农业”时代,基因工程、转基因技术等分子生物学手段广泛应用于植物的遗传育种,基因组学的研究成为植物基因资源发掘的基本科学平台,分子育种成为植物育种的最主要手段之一。为加强与国际植物分子育种领域的合作与交流,推动应用基因与组学植物分子育种科学的发展。The Generation Challenge Programme(全球挑战计划)、国际水稻研究所、海南省科学技术协会、中国农业科学院、海南省热带农业资源开发利用研究所等单位发起,定于2007年3月23-27日在海南省三亚市举办“第二届植物分子育种国际学术研讨会”。大会荣誉…     

Part．2转基因育种技术

植物转基因育种是利用遗传工程的手段，有目的地将外源基因或DNA构建导入植物基因组，通过外源基因的直接表达，或通过对内源基因表达的调控，使植物获新性状的一种品种改良技术。应用转基因育种技术能提高作物产量、改善作物营养品质、增加抗逆能力。[编者按]     

植物学新絮—转基因植物

一九八三年,第一株含有合成蛋白质外源基因的转基因植物成功地诞生了,它标志着植物分子生物学又进入了一个新纪元,为植物遗传工程带来了广阔的前景.之后,在各国生物学家的共同努力下,又成功地育成了许多含有各种优良外源基因的转基因植物.这种遗传工程的方法消除了传统植物育种的盲目性,突破了“亲和性”的限制,只要有理想的供体和受体DNA,遗传工程技术就能使它们的基因结合表达,并稳定地遗传给后代.大大扩大了育种的范围.     

水稻抗稻瘟病基因资源与分子育种策略

稻瘟病是水稻主要病害之一。利用抗病品种是防治稻瘟病最经济、有效和安全的措施。近年来,随着植物先天免疫机制、抗病分子生物学以及水稻和稻瘟菌基因组学研究的不断深入,一系列参与病原菌识别和防卫信号传导与应答,以及外源抗菌蛋白、病原菌激发子等抗病相关基因陆续被鉴定和克隆,为提高水稻抗稻瘟病能力提供了一些新的基因资源、育种策略和技术。本文概述了国内外近年来克隆的主要抗稻瘟病基因资源及其在分子育种研究中应用的进展,提出了通过转基因手段整合不同防卫反应关键调控基因的抗稻瘟病聚合育种策略。     

苦参凝集素蛋白基因转化水稻的研究

以水稻杂交品种‘云资粳41号’为受体材料,通过农杆菌介导法将苦参凝集素蛋白基因(SFL)导入水稻细胞,采用氯酚红法和PCR检测外源基因是否整合到水稻基因组中。结果显示:外源基因成功转入水稻基因组,并获得一批转基因水稻植株;转基因植株叶片离体接种稻瘟病菌的检测结果显示,转基因植株与对照(非转基因植株)相比有明显的抗性,证明SFL基因在水稻中得到表达。研究表明,基于SFL基因所具备的广谱抗菌作用,可以预期所得转基因水稻植株很可能对水稻的多种病原菌具有良好的抗性,为选育新的抗稻瘟病水稻新品种以及拓宽栽培稻抗病遗传基础增加抗稻瘟病基因奠定了基础。     

Production of transgenic rice with agronomically useful genes: an assessment

Rice is the most important food crop in tropical and subtropical regions of the world. Yield enhancement to increase rice production is one of the essential strategies to meet the demand for food of the growing population. Both abiotic and biotic features limit adversely the productivity of rice growing areas. Conventional breeding has been an effective means for developing high yielding varieties, however; it is associated with its own limitations. It is envisaged that recent trends in biotechnology can contribute to the agronomic improvement of rice in terms of yield and nutritional quality as a supplement to traditional breeding methods. Genetic transformation of rice has demonstrated numerous important opportunities resulting in the genetic improvement of existing elite rice varieties and production of new plant types. Significant advances have been made in the genetic engineering of rice since the first transgenic rice plant production in the late 1980s. Several gene transfer protocols have been employed successfully for the introduction of foreign genes to rice. In more than 60 rice cultivars belonging to indica, japonica, javanica, and elite African cultivars, the protocol has been standardized for transgenic rice production. Selection and use of appropriate promoters, selectable markers, and reporter genes has been helpful for development of efficient protocols for transgenic rice in a number of rice cultivars. The present review is an attempt to assess the current state of development in transgenic rice for the transfer of agronomically useful genes, emphasizing the application and future prospects of transgenic rice production for the genetic improvement of this food crop.     

Historical changes in population structure during rice breeding programs in the northern limits of rice cultivation

Key message

The rice local population was clearly differentiated into six groups over the 100-year history of rice breeding programs in the northern limit of rice cultivation over the world.

Abstract

Genetic improvements in plant breeding programs in local regions have led to the development of new cultivars with specific agronomic traits under environmental conditions and generated the unique genetic structures of local populations. Understanding historical changes in genome structures and phenotypic characteristics within local populations may be useful for identifying profitable genes and/or genetic resources and the creation of new gene combinations in plant breeding programs. In the present study, historical changes were elucidated in genome structures and phenotypic characteristics during 100-year rice breeding programs in Hokkaido, the northern limit of rice cultivation in the world. We selected 63 rice cultivars to represent the historical diversity of this local population from landraces to the current breeding lines. The results of the phylogenetic analysis demonstrated that these cultivars clearly differentiated into six groups over the history of rice breeding programs. Significant differences among these groups were detected in five of the seven traits, indicating that the differentiation of the Hokkaido rice population into these groups was correlated with these phenotypic changes. These results demonstrated that breeding practices in Hokkaido have created new genetic structures for adaptability to specific environmental conditions and breeding objectives. They also provide a new strategy for rice breeding programs in which such unique genes in local populations in the world can explore the genetic potentials of the local populations.     

Construction of rice mini-chromosomes by telomere-mediated chromosomal truncation

Telomere truncation has been shown to be an efficient technology for the creation of mini-chromosomes that can be used as artificial chromosome platforms for genetic engineering. Artificial chromosome-based genetic engineering is considered to be superior to the existing techniques of randomized gene integration by Agrobacterium or biolistic-mediated genetic transformation. It organizes multiple transgenes as a unique genetic linkage block for subsequent manipulations in breeding. Telomere truncation technology relies on three components: the telomere sequence that mediates chromosomal truncation, a selection marker that allows the selection of transgenic events, and a site-specific recombination system that can be used to accept future genes into the mini-chromosome by gene targeting. These elements are usually pre-assembled before transformation, a process that is both time and labor consuming. We found in this research that the three elements could be mixed to transform plant cells in a biolistic transformation, and produced efficient chromosomal truncations and mini-chromosomes in rice. This system will allow rapid construction of mini-chromosomes with a flexible selection of resistant markers, site-specific recombination systems and other desirable elements. In addition, a rice telotrisomic line was used as the starting material for chromosomal truncations. Mini-chromosomes from the truncations of both the telocentric chromosome and other chromosomes were recovered. The mini-chromosomes remained stable during 2 years of subculture. The construction of mini-chromosomes in rice, an economically important crop, will provide a platform for future artificial chromosome-based genetic engineering of rice for stacking multiple genes.     

药用野生稻TAC克隆转化籼稻的体系初探

采用已构建的药用野生稻TAC文库,比较研究4个籼稻品种在不同培养基的诱导率及愈伤组织对潮霉素抗性。通过2种不同诱导方法产生的愈伤组织,将携带药用野生稻大片段DNA的TAC克隆转化到籼稻品种中的结果表明,除了‘粤香占’以外,其它3个品种在心诱导培养基中添加微量B,后,其愈伤诱导率最高。不同品种的潮霉素筛选适合浓度存在差异,其中‘华粳籼74’的适合筛选浓度为50mg．L-1,‘粤香占’为40mg．L-1。用预培养5d的愈伤组织进行遗传转化,在潮霉素筛选之前先以头孢拉定抑菌处理的,容易获得转基因植株。4个品种中以‘粤香占’的抗性愈伤组织筛选率和分化率最高,分别为22．58％和14．86％。分子检测11株转基因水稻的结果表明,其中8株含有抗性标记基因。据此认为,药用野生稻TAC文库在水稻创新育种中可能有一定的利用前景。     

水稻SSR标记的遗传多样性研究进展

本文从SSR标记优点和适用于研究水稻遗传多样性入手,综述了SSR标记在水稻核心种质构建与评价、遗传结构、稻种起源演化等方面的研究进展。总结了水稻遗传多样性的地带性特征（云南是中国稻种资源的最大遗传多样性中心和优异种质的富集地;西南稻区粳稻品种遗传多样性最丰富;南方稻区粳稻品种的遗传多样性高于北方粳稻遗传多样性）、遗传多样性与生态地理位置密切相关、目前水稻品种遗传基础狭窄、多样性降低等特征,分析了遗传多样性成因及影响因素,特别指出了育种行为对遗传多样性的影响,并针对当前水稻品种遗传多样性较低的问题提出了对策。     

Advances to improve the eating and cooking qualities of rice by marker-assisted breeding

The eating and cooking qualities of rice are heavily emphasized in breeding programs because they determine market values and they are the appealing attributes sought by consumers. Conventional breeding has developed traditional varieties with improved eating and cooking qualities. Recently, intensive genetic studies have pinpointed the genes that control eating and cooking quality traits. Advances in genetic studies have developed molecular techniques, thereby allowing marker-assisted breeding (MAB) for improved eating and cooking qualities in rice. MAB has gained the attention of rice breeders for the advantages it can offer that conventional breeding cannot. There have been successful cases of using MAB to improve the eating and cooking qualities in rice over the years. Nevertheless, MAB should be applied cautiously given the intensive effort needed for genotyping. Perspectives from conventional breeding to marker-assisted breeding will be discussed in this review for the advancement of the eating and cooking qualities of fragrance, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT) in rice. These four parameters are associated with eating and cooking qualities in rice. The genetic basis of these four parameters is also included in this review. MAB is another approach to rice variety improvement and development in addition to being an alternative to genetic engineering. The MAB approach shortens the varietal development time, and is therefore able to deliver improved rice varieties to farmers within a shorter period of time.     

How Can We Use Genomics to Improve Cereals with Rice as a Reference Genome?

Rice serves as a model crop for cereal genomics. The availability of complete genome sequences, together with various genomic resources available for both rice and Arabidopsis, have revolutionized our understanding of the genetic make-up of crop plants. Both macrocolinearity revealed by comparative mapping and microcolinearity revealed by sequence comparisons among the grasses indicate that sequencing and functional analysis of the rice genome will have a significant impact on other cereals in terms of both genomic studies and crop improvement. The availability of mutants, introgression libraries, and advanced transformation techniques make functional genomics in rice and other cereals more manageable than ever before. A wide array of genetic markers, including anchor markers for comparative mapping, SSRs and SNPs are widely used in genetic mapping, germplasm evaluation and marker assisted selection. An integrated database that combines genome information for rice and other cereals is key to the effective utilization of all genomics resources for cereal improvement. To maximize the potential of genomics for plant breeding, experiments must be further miniaturized and costs must be reduced. Many techniques, including targeted gene disruption or allele substitution, insertional mutagenesis, RNA interference and homologous recombination, need to be refined before they can be widely used in functional genomic analysis and plant breeding.     

DNA methylation polymorphism and stability in Chinese indica hybrid rice

Conventional rice breeding has long focused on exploiting the DNA sequence diversity. However, epigenetic diversity, reflected particularly in DNA methylation, can also contribute to phenotypic variation and should not be overlooked in rice breeding. In this study, 20 parental lines of indica rice, which are widely used in hybrid rice breeding in China, were analyzed to investigate variations of DNA methylation and its inheritance. The results revealed a wide diversity in DNA methylation among these breeding lines. A positive correlation was seen between DNA methylation and genetic diversity. Furthermore, some of the methylated DNA was inherited in the subsequent generation, regardless of whether they were produced by selfing or hybrid-crossing. This study provides insight into the methylation patterns in rice, and suggests the importance of epigenetic diversity in rice breeding.     

水稻抗性转基因研究进展

随着水稻遗传转化技术的发展,通过基因工程手段获得抗病虫草害及逆境水稻品种成为可能。本文综述了近年来国内外水稻抗性转基因的技术、方法和策略等研究现状、发展趋势、存在的问题及解决方法,对水稻抗性转基因在水稻育种上的应用也作了评价。