云南疣粒野生稻稻瘟病抗性

野生稻(Oryza rufipogo)保存有许多栽培稻(O. sativa)不具备或已经消失的优异基因资源, 是扩大栽培稻遗传背景、改良产量与品质、提高抗病虫害及抗逆境能力的重要基因库。疣粒野生稻(O. meyeriana)是中国3种野生稻资源之一, 主要分布在云南。为进一步了解其稻瘟病抗性, 首先利用来自不同稻作区的稻瘟病菌株, 通过注射接种法对疣粒野生稻进行系统的稻瘟病抗性鉴定, 发现疣粒野生稻对接种的所有稻瘟病菌株都感病。进一步采用3'/5' RACE方法, 从疣粒野生稻中克隆了水稻同源基因Pid2和Pid3, 并构建过表达转基因株系对基因功能进行了研究。结果表明, Pid2和Pid3与疣粒野生稻中同源基因间在DNA和氨基酸水平上有较大的序列差异, 过表达转基因的日本晴植株对稻瘟病菌的敏感性与对照相似。推测疣粒野生稻在自然接种条件下, 表现出的抗稻瘟病表型很可能是其旱生叶片结构特征形成了对稻瘟病菌侵染的天然屏障。对控制疣粒野生稻这一类性状基因资源的挖掘和利用, 有利于优良抗性水稻品种的培育。研究结果为疣粒野生稻的研究利用提供了新信息和新思路。     

水稻草矮病毒在水稻原生质体中的表达

通过建立水稻原生质体培养体系,经多聚鸟氨酸（PLO）介导将提纯的水稻草矮病毒（Rice grassy stunt virus,RGSV）接种到水稻原生质体内,利用酶联免疫吸附法（ELISA）及蛋白免疫印迹法（Western blot）,研究RGSV在水稻原生质体内的生长周期及其编码蛋白的表达情况。结果表明： RGSV在接种后24h左右开始在原生质体内复制,36h左右达到最大值。NS6在15h左右开始表达,在30h左右达到最大值。     

水稻条纹病毒胁迫下的水稻全基因组表达谱

水稻条纹叶枯病由水稻条纹病毒(Rice stripe virus, RSV)引起,对我国水稻生产危害严重.为了明确RSV侵染对水稻基因表达谱的影响,采用Affymetrix水稻全基因组芯片对RSV接种后出现条纹症状第7天的武育粳3号水稻病叶和相应的健康叶片进行了全基因组表达谱分析,得到3 517个差异基因,其中2 002个表达上调,1 515个表达下调.根据TIGR数据库注释(http://www.tigr.org/tdb/e2k1/osa1/)和MIPS基因功能分类标准(http://mips.gsf.de/projects/funcat)将差异基因归类为15个功能类别,多数差异基因与植物防御、信号传导及蛋白质、碳水化合物的代谢相关,一些转录因子的表达也发生了明显的变化.代谢途径分析表明,RSV侵染后磷酸戊糖途径、类黄酮合成途径和芸苔素合成途径的相关基因表达明显增强,赤霉素合成途径相关基因的表达受到了抑制.     

稻田杂草稻发生情况调查

2007年杂草稻在江苏省海安县各类稻田中的发生率达44．35％,平均每公顷穴数和穗数分别为1023穴和10796穗,最高田块分别达12万穴和180万穗,已成为水稻生产上的潜在威胁。杂草稻在不同稻田的发生程度表现以下趋势：轻-中壤〉砂-轻壤〉重壤土稻田、直播〉抛栽〉机插〉手栽稻田、非统一供种〉统一供种稻田。     

Comparative Cytology of Rice Tungro Viruses in Selected Rice Cultivars

Ultrastructural studies were made using plants of five selected rice cultivars infected with rice tungro viruses. In all cultivars, rice tungro bacilliform virus (RTBV) was found in both xylem and phloem, while rice tungro spherical virus (RTSV) was observed only in the phloem. In tolerant cultivars Balimau Putih and Utri Merah, plants infected with RTBV and RTSV or RTBV alone, had fewer cells containing tungro viruses than plants of the sensitive cultivar Taichung Native 1. In RTBV-sensitive cultivars FK 135 and ASD 8 infected with both viruses or RTBV alone, electron-dense cytoplasm was observed in most cells of the phloem. Abundant phloem necrosis was also observed in FK 135. These observations were correlated with the reaction of each rice cultivar to tungro infection.     

试论野生稻高蛋白种质在水稻育种中的应用

本文探讨野生稻高蛋白种质在水稻育种中应用的必要性、意义和可行性,提出研究应用的发展重点;认为水稻品质育种应利用野生稻高蛋白种质,加强专用水稻育种和高蛋白种质分子学研究。     

水稻蛋白质组学研究进展

蛋白质组是一个基因组所表达蛋白质的总称,研究内容包括蛋白质基本氨基酸序列的鉴定到相关性状、修饰、功能及不同类型蛋白分子相互作用等等。本文简要介绍了蛋白质组学的产生背景,以及主要研究技术包括双向电泳(2D-PAGE)质谱、蛋白质芯片、酵母双杂交,并重点介绍了近期水稻蛋白质组学应用研究进展。     

Ceramide in Rice Grain

A rice lamina inclination test that is simple and specific for brassinosteroids was used as a micro-quantitative bioassay for brassinolide 1 and its 6-keto congener, castasterone 2, in the concentration range of 5 x 10^–5 /ig/ml to 5 x 10^–3μg/ml, when uniform seedlings of the rice cultivars Arborio J-l and Nihonbare were selected. A phytohormone, indole-3-acetic acid (IAA), showed similar activity in this bioassay. Its lowest effective concentration, however, was 50 /ig/μl, about five orders of magnitude greater than that of brassinolide. Other phytohormones, abscisic acid (ABA) and the cytokinins kinetin and A⁶-benzyladenine, inhibited the lamina inclination of rice seedlings. The addition of a cytokinin reduced the promoting effect of brassinolide. Thus, the rice lamina inclination test can be used both as a micro-quantitative bioassay for brassinosteroids and as a method for detecting antibrassinolide compouds.     

Rice production in Afghanistan

Rice, Afghanistan’s third most important crop, is produced in every province. Although about thirteen varieties occur in the country, for marketing purposes two main classes are recognized. These two, “Loke” and “Mai-een”, are differentiated on the basis of grain size, color, consistency, and distribution.     

Double-Stranded RNA in Rice

Oryza sativa ) and wild rice (O. rufipogon) tissues. It is detected at every developmental stage, and is transmitted very efficiently to progeny via seeds (more than 98%). The dsRNA is maintained at a constant level (approximately 100 copies/cell) in almost all tissues. However, the number of copies increases about 10-fold when host cells are grown in suspension culture. Complete nucleotide sequences of cultivated rice (temperate japonica rice, cv. Nipponbare, J-dsRNA) and wild rice (W-1714, W-dsRNA) dsRNAs have been determined. Both wild and cultivated rice dsRNAs have a single long open reading frame (ORF) containing the conserved motifs of RNA-dependent RNA polymerase and RNA helicase. The coding strands of both contain a site-specific discontinuity (nick) at nt 1,211 (J-dsRNA) or at nt 1,197 (W-dsRNA) from the 5′ end of their coding strand. Rice dsRNA has several unique properties and can be regarded as a novel RNA replicon. This paper discusses the origin and evolution of the rice dsRNA. Received 23 October 1998/ Accepted in revised form 15 December 1998     

水稻的功能基因组学

文章介绍近几年来水稻结构基因纽学、基因表达的大规模分析平台、全基因纽的突变群体库以及基因分离克隆方法上的研究进展。     

Rice fermentation in ecuador

Fermented rice, or “Sierra rice”, of Ecuador, is distributed and consumed exclusively in the Andean Sierra. Fermenting precooks the rice, thus reducing the cooking time in the Andean Highlands. “Sierra rice” is the only type used in preparation of “dry rice”, which is considered indispensable to all meals.     

几条水稻MAR序列的克隆及其功能分析

利用水稻基因组数据库和MAR预测技术,快速筛选和克隆到10条水稻MAR序列。将其分别构建到转基因结构的两侧并整合到水稻中,分析所克隆的序列对转基因表达的功能效应。结果表明:其中的3条序列具有MAR序列的功能,能明显地提高外源转基因的表达水平和表达稳定性,转基因的表达水平平均提高约2~19倍,最高可达28.9倍。     

Expression of Rice Stripe Virus Coat Protein Gene in Transgenic Rice Plants

Rice stripe virus (RSV) is a pathogen of rice stripe disease causing great damage to rice. The disease is transmitted by Laodelphax striatellus and three other planthoppers. RSV infects as much as 37 cereals including rice, wheat, maize and results in a significant reduction in yield in epidemic year. In order to develop efficient means of controlling the disease, authors have studied the amino acid composition of RSV coat protein (CP), synthesized and cloned the cDNA to CP, sequenced the full-length CP gene. Having inserted the RSV CP gene into plant expression vector pROK Ⅱ, authors transformed rice suspension culture via microprojectile bombardment and obtained transgenic plants expressing the CP gene. The suspension culture was initiated by inoculating yellowish, compact and embryogenic calli derived from seeds into suspension medium containing proline and maltose. After being cultured at 26℃ in the dark for about half a year, finely-dispersed and embryogenic suspension culture was estabolished. Before bombardment the suspension culture was evently applied onto three-layered filter-paper discs in a petri dish. CaCl2 and spermidine was employed to coat tungsten particle with plasmid DNA. 2.5 μl of coated particle was loaded onto bullet and each dish was bombarded three times. Immediately after being bombarded, the suspensions were cultured in modified N6 medium. 2 days later the suspensions were transferred to the same medium but containing G418, which were subcultured weekly. Being subject to G418 selection for two months, white and fast-growing clones were emerged from the brownish cultures. Green plants regenerated when the resistant calli were transferred to differentiation medium. The regenerated plants were firm enough to grow well in the greenhouse. 10 plants regenerated from G418 resistant calli were tested for their transformed nature by Southern blot using 32P-labelled CP gene as a probe. Among the plants tested, 2 plants showed clearly hy bridizing bands with a molecular weight corresponding to RSV CP gene. Western blot further demonstrated that RSV CP gene was expressed in transgenic rice plants. At present tests on the antiviral effects of transgenic plants by feeding plantphoppers infccted with RSV are being underway.     

来自中国云南野生稻的抗稻瘟病遗传资源

与Pi-ta^＋等位基因相比,含有Pi-ta^＋等位基因的栽培稻具有抗稻瘟病特性。本研究用基因序列分析的方法检测了来自云南的不同栽培稻品种以及不同类型和来源的普通野生稻种和非洲长雄蕊野生稻种中的Pi-ta^＋基因,发现Pi-ta地基因在稻属植物中高度保守,但Pi-ta^＋等位基因的存在极其稀有。在所检测的栽培稻和野生稻中仅有来源于云南景洪的直立型普通野生稻中含有Pi-ta^＋等位基因。而与Pi-ta基因相比,另一个水稻抗稻瘟病基因Pib,经部分同源序列克隆及测序发现该基因在不同野生稻中的变异较大。在所克隆的不同野生稻Pib基因同源序列中,也只有来源于直立型普通野生稻的序列能按该基因的开放阅读框进行正常翻译。对不同类型普通野生稻的抗稻瘟病能力的初步鉴定结果表明,直立型普通野生稻对供试的本地稻瘟病生理小种具有较强抗性,其抗性可能源于所含的Pi=ta^＋等位基因及可能有功能的Pib基因。由于普通野生稻与栽培稻同属AA基因组型,因此,云南直立型普通野生稻可通过杂交育种或基因工程途径用于栽培稻的抗稻瘟病性能改良。     

Gibberellin Signal Transduction in Rice

Rumex acetosa L. (common sorrel) is a dioecious perennial in the family Polygonaceae. Gibberellins (GAs) of the early 13-hydroxylation pathway and the putative early 3, 13-hydroxylation pathway were previously identified in young R. acetosa inflorescences by GC-MS. In this investigation to examine the GA content of individual inflorescences ELISAs were used for quantitative analysis. Significant differences were revealed between the sexes in the GA content of young inflorescences, and GC-SRM was used to validate the observed trends. Males had higher levels of the 3, 13-hydroxylated C₂₀-GA GA₁₈ and the 2, 13-hydroxylated C₁₉-GA GA₂₉, whereas females had higher levels of the 13-hydroxylated C₂₀-GAs GA₅₃ and GA₁₉. It is suggested that the conversion from C₂₀-GAs to C₁₉-GAs is under tighter control in the inflorescences of females compared to male plants and therefore there is accumulation of the C₂₀-GAs in the females. Results from flowering bioassays using authentic GAs indicate that differences in GA content between the sexes are unlikely to be a consequence of sex determination.