裸粒稻形态及生理特性的初步研究

福建省龙溪地区农业科学研究所陈井泉与张耀龙选育的“麦稻”或称“裸粒稻”,曾在1978年2月中国科学院在武汉召开的第一次全国植物远缘杂交经验交流会上作了报道和展览。由于它的穗部性状特异,且据最近报道它已继续稳定至第十代,有可能是由于水稻及小麦杂交而引起的变异。因之这项原始材料可用作发育遗传研究,或者培育裸     

水稻幼穗-颖花发育的研究进展

水稻是世界上最重要的粮食作物之一,也是单子叶植物发育生物学研究的理想模式植物,水稻幼穗和颖花的发育还是最终产量赖以依托的基础。对水稻幼穗和颖花发育的研究已成为植物分子遗传学和作物科学共同的研究焦点。近年来,有关水稻幼穗和颖花发育的研究取得了长足的进展,本文对幼穗和颖花的发育过程、栽培措施和环境因子对幼穗和颖花发育的影响以及幼穗和颖花发育的相关基因等方面的国内外进展进行了综述,同时指出了目前研究中存在的问题及相应的研究对策。     

东乡野生稻BILs群体耐低氮性表型性状指标筛选及其综合评价

为了鉴定东乡野生稻及其后代群体的耐低氮性,研究低氮和正常氮2种处理下“协青早B//东乡野生稻/协青早B”BC₁-F₁₂回交重组自交系株高、抽穗期、穗长、有效穗数、穗实粒数、穗总粒数、着粒密度、结实率、千粒重和单株产量等10个表型性状,利用主成分分析和模糊隶属函数对BILs群体的耐低氮性进行综合评价.结果表明： 株系116、143和157的耐低氮性强,可作为东乡野生稻耐低氮性遗传研究和水稻耐低氮性育种的中间材料.采用逐步回归分析法建立了耐低氮性最优回归方程,筛选到株高、穗总粒数、结实率、千粒重和单株产量等5个性状相对值可作为水稻全生育期耐低氮性的综合评价指标.因此,在水稻耐低氮性遗传改良中,应注重对这5个性状,尤其是穗总粒数和单株产量相对值的选择.
     

单子叶植物RNA干扰和过表达Gateway载体的构建

基因枪和农杆菌介导的遗传转化是目前常用的两种单子叶植物遗传转化方法。载体的发展和改良是提高植物遗传转化效率的重要基础,RNA干扰载体和过表达载体是目前通过遗传转化研究植物基因功能的主要工具。Gateway克隆技术是一种基于lambda噬菌体特异位点重组特性的通用克隆技术,该技术可以将大批目的基因方便、快捷地连接到受体载体上。本文利用Gateway技术结合传统酶切、连接方法,构建了适用于单子叶植物基因枪和农杆菌转化的RNA干扰Gateway载体pAHC-PSK-RNAi、pClean-G185-RNAi和过表达Gateway载体pAHC-PSK-OE和pClean-G185-OE,为利用基因枪和农杆菌介导的遗传转化,在小麦和水稻等单子叶植物中进行规模化基因功能研究奠定了基础。     

密穗型水稻品种籽粒垩白性状改良研究

采用籽粒长宽比较大、穗部着粒密的散穗型材料(EG23)改良粳稻密穗型品种的籽粒垩白性状.结果表明,经改良后得到的密穗型品系EA6,与原亲本浙粳20比较,其穗部长度缩短,每穗总粒数增加,着粒密度增大,而籽粒垩白特性得到明显的改善,表明在穗部长度和着粒结构未得到改良的情况下,调节籽粒长宽比对改善密穗型品种籽粒垩白性状具有可能性.穗部不同粒位籽粒垩白性状改良的效果不同,穗顶部和穗中部的改良效果明显优于穗基部.设计的4个不同杂交配组方式中,以反回交配组方式(浙粳20/ EG23//浙粳20)选育效果最好.EA6具有较好的农艺性状,既可作为优异种质资源利用,也可直接应用于生产.这一结果从育种实践上较好地协调了密穗型品种高产与优质的矛盾,对于培育既有密穗型的高产株型又有优良籽粒外观品质的水稻品种具有重要意义.     

植物气孔发育机制研究进展

气孔是分布在植物表面的微孔, 是植物水分散失和与外界环境进行气体交换的门户。经过多年的研究, 气孔发育过程中重要调节因子陆续被发现。气孔复合体结构、发育起始模式以及在双子叶植物和单子叶植物中的分布都有较大差异。该文综述了双子叶植物拟南芥(Arabidopsis thaliana)气孔发育过程中调控因子、细胞极性分裂以及环境因子和植物激素调控气孔发育的机制; 还阐述了单子叶植物玉米(Zea mays)、二穗短柄草(Brachypodium distachyum)和水稻(Oryza sativa)气孔发育方面的研究进展, 并展望了气孔发育的研究方向。     

长雄野生稻有利基因的发掘与利用

人类将普通野生稻驯化为亚洲栽培稻,其农艺性状如株高、落粒性、穗型等发生了重要变化,产量也大幅提高,但许多优良性状如抗逆性等却丢失。长雄野生稻与亚洲栽培稻同属AA基因组,蕴藏了许多生物胁迫和非生物胁迫的抗性基因,被认为是亚洲栽培稻遗传改良的潜在基因库。本文总结了长雄野生稻生物及非生物胁迫抗性、地下茎性状以及其他潜在应用价值性状,包括白叶枯抗性、抗旱性、耐热性、自交不亲和性、氮高效利用以及高产等有利性状。基于长雄野生稻地下茎性状开展多年生稻育种实践的应用研究,对长雄野生稻进行从头驯化的策略进行了探讨,以期为长雄野生稻基础研究及栽培稻遗传改良提供理论参考。     

一份绿米水稻种质资源的发现及初步研究

稻米色泽是水稻种质资源多样性的重要组成部分,也是满足彩色稻米市场需求的重要物质基础。本研究团队在野生稻种质资源整理过程中发现了一份包含部分绿米(果皮呈绿色)的资源,经过多代自交,获得稳定的高代品系,命名为LM8。LM8光敏感性强,易与亚洲栽培稻杂交,在广西晚稻种植株高为117.7 cm,剑叶长32.1 cm,剑叶宽1.1cm,穗长22.5 cm,有效分蘖数19,株型直立紧凑。千粒重8.73 g,粒长5.76 mm,粒宽2.09 mm,粒型椭圆,富含脂肪和人体所必需微量元素。亲缘关系研究结果表明,LM8属AA基因组,与亚洲栽培稻在同一个组,应不属于野生稻。但是,LM8在发现初期具有有芒、落粒性强、颖壳坚硬呈深褐色等野生性状,因此推测LM8为杂草稻类型。LM8的发现及研究不仅可以促进水稻果皮颜色遗传发育调控网络的建立和完善,也能够为创制绿色稻米水稻新品种提供遗传材料,满足消费者多元化选择并在乡村振兴中发挥重要作用。     

小麦遗传转化技术研究进展

植物基因工程研究兴起于本世纪八十年代中期。自其诞生至今,如何将这项技术应用于小麦、水稻、玉米等农作物的遗传改良研究便始终是人们努力的重要目标之一。要实现这一目标,首先需要建立一套高效、可靠、重复性好的基因转化系统。而在植物基因转化系统研究方面,禾谷类相对于其他双、单子叶植物而言,具     

裸粒水稻颖壳性状的遗传规律研究

裸粒水稻自1973年出现［[17以来,引起许多 科研单位的关注。中国科学院遗传研究所作了 细胞学的观察研究［[27,中国科学院上海植物生 理研究所进行了形态及生理特征的研究[97,南 京大学生物系及中国科学院上海植物生理研究 所给裸粒水稻订了学名〔41,福建省龙溪地区农 科所在回交改造上作过初步的探讨［[5,61。由于裸 粒水稻颖壳的特异性而造成裸粒,既有可能为 水稻育种上提供一个新的种源或资源,又可能 为育成能在生产上应用的裸粒稻提供一个好的 基础材料。为此,本研究目的则在于探索裸粒 水稻与栽培稻回交改造中的颖壳性状遗传规 律,为继续改造利用提供参考。     

水稻花发育的分子生物学研究进展

水稻是世界上最重要的粮食作为之一,也是单子叶植物发育生物学研究较理想的模式植物。水稻花器官还是粮食赖以形成的基础。对水稻花发育的研究已开始成为植物分子遗传学的一个新的焦点。近年来有关水稻花发育基因调控的研究已取得了长足的进展,本文从水稻花的诱导、花分生组织的形成和花器官的发育三个方面综述近年来国内外的研究进展。 Abstract:Rice (Oryza sativa L.) is not only one of the most important food crops in the world,but also a model plant for study of molecular developmental biology in monocots.In addition,the rice floral organs provide the basis for grain formation.Study of rice floral development has become a new focus of plant molecular genetics.Recently,notable progress has been made in study of gene regulation in rice floral development.In the review,genetic and molecular mechanisms of floral induction,floral meristem formation,and floral organ development in rice are summarized.     

The dynamic gene expression from different genetic systems for protein and lysine contents of indica rice

The dynamic expression of genes for protein and lysine contents of rice grain under different environments was carried out with time-dependent measures by using the developmental genetic models for quantitative traits of triploid endosperm in cereal crops. The results showed that the genetic effects, especially genotype × environment (GE) interaction effects from the genes expression of different genetic systems including triploid endosperm, cytoplasm and diploid maternal plant were important for the performance of both nutrient quality traits at all developmental times/stages of rice grain. The conditional genetic variance analysis found that the activation of quantitative genes especially from endosperm and maternal plant genetic systems for protein and lysine contents was gradually carried through the developmental process of rice grain. The net genetic effects showed that the new expression of quantitative genes for protein and lysine contents was more active at late filling stage (15–21 days after flowering) and maturity stage (22–28 days) of rice grain. Also the sequential expression of cytoplasmic genes cannot be ignorable for the development of nutrient quality traits. The phenomena that some genes could continuously express for several developmental stages or the genes expression could be interrupted among developmental stages of rice grain was detected especially for net endosperm additive main effects or maternal additive main effects. The differences of genetic relationships from different genetic systems were found for protein and lysine contents among developmental times of rice grain.     

水稻基因组加倍对籽粒大小调控基因表达的影响

水稻是最重要的粮食作物之一,提高水稻产量一直是育种的主要目标。水稻四倍体相对于二倍体具有籽粒变大、粒重增加的特点,研究基因组加倍后籽粒大小基因的调控模式,在育种应用方面具有十分重要的意义。本文以二倍体 -四倍体水稻为材料,分析6个控制籽粒大小基因在幼穗发育中的表达差异,同时结合转基因实验,探讨基因剂量增加对基因表达水平和籽粒大小的影响。结果发现：基因组加倍后,水稻的发育进程不变,但株高增加,叶片变宽,籽粒变大,增大后的籽粒在籼稻表现为长、宽均增加显著,而在粳稻中长度比宽度增加更为明显。进一步分析控制籽粒大小基因的表达差异情况,发现这些基因的表达不仅受发育时期的影响,在籼粳亚种间也明显不同,即受遗传背景的影响。在基因组加倍的情况下,正调控基因GS5、HGW的表达普遍高于对应的二倍体;负调控基因GS3在籼稻D9311中趋于下调或沉默,而在粳稻DBl中趋于上调,GW2在D9311中上调,而在DBl中趋于沉默。通过转基因实验分析负调控基因GW2在二倍体Bl中的表达趋势,发现其在基因剂量线性增加的情况下,表达水平高于二倍体和四倍体,导致其籽粒变小。本研究结果有助于了解水稻中控制籽粒大小的基因在二倍体和四倍体中的表达模式,为高产育种提供理论依据。     

Towards molecular breeding of reproductive traits in cereal crops

The transition from vegetative to reproductive phase, flowering per se , floral organ development, panicle structure and morphology, meiosis, pollination and fertilization, cytoplasmic male sterility (CMS) and fertility restoration, and grain development are the main reproductive traits. Unlocking their genetic insights will enable plant breeders to manipulate these traits in cereal germplasm enhancement. Multiple genes or quantitative trait loci (QTLs) affecting flowering (phase transition, photoperiod and vernalization, flowering per se ), panicle morphology and grain development have been cloned, and gene expression research has provided new information about the nature of complex genetic networks involved in the expression of these traits. Molecular biology is also facilitating the identification of diverse CMS sources in hybrid breeding. Few Rf (fertility restorer) genes have been cloned in maize, rice and sorghum. DNA markers are now used to assess the genetic purity of hybrids and their parental lines, and to pyramid Rf or tms (thermosensitive male sterility) genes in rice. Transgene(s) can be used to create de novo CMS trait in cereals. The understanding of reproductive biology facilitated by functional genomics will allow a better manipulation of genes by crop breeders and their potential use across species through genetic transformation.     

PAY1 improves plant architecture and enhances grain yield in rice

Plant architecture, a complex of the important agronomic traits that determine grain yield, is a primary target of artificial selection of rice domestication and improvement. Some important genes affecting plant architecture and grain yield have been isolated and characterized in recent decades; however, their underlying mechanism remains to be elucidated. Here, we report genetic identification and functional analysis of the PLANT ARCHITECTURE AND YIELD 1 (PAY1) gene in rice, which affects plant architecture and grain yield in rice. Transgenic plants over‐expressing PAY1 had twice the number of grains per panicle and consequently produced nearly 38% more grain yield per plant than control plants. Mechanistically, PAY1 could improve plant architecture via affecting polar auxin transport activity and altering endogenous indole‐3‐acetic acid distribution. Furthermore, introgression of PAY1 into elite rice cultivars, using marker‐assisted background selection, dramatically increased grain yield compared with the recipient parents. Overall, these results demonstrated that PAY1 could be a new beneficial genetic resource for shaping ideal plant architecture and breeding high‐yielding rice varieties.     

2014年中国植物科学若干领域重要研究进展

2014年中国植物科学高速稳步发展,表现在具有原创意义的高质量论文迅速增长。中国科学家在植物学诸多领域,如水稻(Oryza sativa)独脚金内酯信号转导途径、水稻代谢遗传调控、水稻育性的遗传调控机理及农业与环境生物学等取得了大量重要成果,基因组研究从功能到进化、从模式作物扩散到各类经济作物,表现出全方位多维度的整合研究态势。全球气候变化下碳汇响应机制取得重要进展。Nature等国际学术刊物高度关注中国植物科学特别是水稻生物学研究进展。该文概括性综述了2014年中国本土植物科学若干领域取得的重要研究进展,旨在全面追踪当前中国植物科学领域发展的最新前沿和热点事件,并与国内读者分享我国科学家所取得的杰出成就。     

Symbiont-mediated adaptation by planthoppers and leafhoppers to resistant rice varieties

For over 50 years, host plant resistance has been the principal focus of public research to reduce planthopper and leafhopper damage to rice in Asia. Several resistance genes have been identified from native varieties and wild rice species, and some of these have been incorporated into high-yielding rice varieties through conventional breeding. However, adaptation by hoppers to resistant rice has been phenomenally rapid, and hopper populations with virulence against several resistance genes are now widespread. Directional genetic selection for virulent hoppers seems unlikely given the rapid pace of adaptation reported from field and laboratory studies. Among the alternative explanations for rapid hopper adaptation are changes (genetic, epigenetic, or community structure) in endosymbiont communities that become advantageous for planthoppers and leafhoppers that feed on resistant rice varieties. This review examines the nature of these symbiont communities and their functions in planthoppers and leafhoppers—focusing on their likely roles in mediating adaptation to plant resistance. Evidence from a small number of experimental studies suggests that bacterial and eukaryotic (including yeast-like) symbionts can determine or mediate hopper virulence on rice plants and that symbiont functions could change over successive generations of selection on both resistant and susceptible plants. The review highlights the potential complexity of rice hopper–symbiont interactions and calls for a more careful choice of research materials and methods to help reduce this complexity. Finally, the consequences of symbiont-mediated virulence adaptation for future rice breeding programs are discussed.     

Molecular Genetics and Developmental Physiology: Implications for Designing Better Forest Crops

Current tree biology related to tree genetics and breeding has two important developments that have not well been integrated in the literature. The first is the physiological and biochemical dissection of plant yield, whereas the second is the genetic mapping based on molecular markers, such as RFLPs, RAPDs, AFLPs, and microsatellites. Genetic mapping has revolutionized traditional quantitative genetic analysis by which the genetic variation of a character is described in terms of its mean and (co)variance without the knowledge of the underlying genes. By integrating physiological and developmental studies of yield traits, genetic mapping can provide a unique means for detecting key QTL that play important roles in affecting tree growth and metabolism. The incorporation of these QTL into commercial populations through gene transformation or marker-assisted selection will move current breeding programs strictly based on an empirism to an approach that is mechanistically oriented. In this review, we discuss how plant physiology and development are merged with genetic mapping to formulate the strategy of molecular breeding in which superior forest crops are selected at the gene level. It is anticipated that this novel breeding strategy can potentially provide major breakthroughs for tree breeding.     

水稻产量数量性状的遗传调控机制研究进展

粒重、每穗粒数和每株穗数是决定水稻产量的三大要素,也是水稻育种改良的重点．这些性状都是遗传复杂的数量性状．近十年来,水稻数量性状遗传学领域取得了突破性的进展,成功克隆了一批控制水稻产量性状的数量性状位点（QTL）．本文将简要介绍产量性状相关QTL的功能与作用机制．这些研究成果不仅有助于揭示产量性状形成的遗传基础,也将有力推动水稻分子设计育种的进程．     

小麦丰产资源的筛选与创新研究

在二十余年小麦大粒、穗重资源研究与创新基础上,2000-2006年对2878份小麦种质资源进行研究,筛选出千粒重50~59.9g的大粒种质256份,占全部资源的8.9%;千粒重60~69.9g的稀有大粒种质93份,占全部资源的3.2%;千粒重70g以上的珍贵大粒种质8份,占全部资源的0.3%。筛选出单穗重2~2.49g的穗重种质176份,占全部资源的6.1%;单穗重2.5~2.99g的稀有穗重种质83份,占全部资源的2.88%;单穗重3g以上的珍贵穗重种质19份,占全部资源的0.66%。探索出大粒、穗重型种质创新的途径是:理想株型与大粒、穗重性状相结合;保产性状与大粒、穗重性状相结合;优良品质性状与大粒、穗重性状相结合;常规技术与现代生物技术相结合。通过创新,培育出一批优良的大粒、穗重型中间材料,可为超级小麦育种提供优良的基因源,促进超级小麦育种的发展。