中国栽培稻等位酶的遗传结构及地理分布

对我国6330份栽培稻品种进行了5种等位酶12个位点的遗传结构分析,共检测到53个等位基因,平均等位基因数为4.41,多样性指数值为0.269,表明中国栽培稻具有丰富的等位酶遗传多样性。地方农家品种和现代育成品种遗传多样性指数差异不大,但现代育成品种等位基因较少,共有13个稀有等位基因仅存在于地方农家品种中。比较我国六大生态稻区的等位酶分布,发现西南稻区的等位酶基因最为丰富,为我国稻种资源的多样性中心,但华北和华中稻区在某些等位酶基因上的多样性以及某些稀有等位基因的存在暗示着淮河流域和长江流域可能与栽培稻的起源有关。利用等位基因聚类分析基本可以把地方农家品种分成两大类,分别是籼稻和粳稻,籼稻的遗传多样性大于粳稻。籼粳稻在等位酶位点上的差异不仅表现为单个等位基因形式和频率的不同,还表现为多位点非随机组合的遗传差异。     

山西省大豆地方品种与选育品种农艺性状及SSR标记遗传多样性比较分析

以山西省地方品种和选育品种为材料，对其质量性状、数量性状及SSB标记进行了遗传多样性分析。旨在探明地方品种与选育品种之间遗传多样性的差异，为山西省大豆品种资源的研究与利用提供理论依据。结果表明，184份选育品种和180份地方品种在8个质量性状、5个数量性状上都存在较广泛的遗传多样性。选育品种与地方品种相比，遗传多样性较低。在质量性状方面，选育品种的籽粒颜色、生长习性变异性呈下降趋势，而脐色和茸毛色都表现出增加的趋势；在数量性状方面，除粗蛋白低于选育品种外，地方品种的变异程度高于选育品种。对两类品种各13份材料进行SSR分析，结果表明，45个SSR位点基本可以将地方品种和选育品种分开，表明地方品种和选育品种在分子水平上也发生了一定的分化，但地方品种的遗传多样性要高于选育品种。表型和分子检测结果都表明，山西大豆品种的选育在一定程度上降低了遗传多样性。     

野生大豆遗传多样性研究Ⅰ4个天然居群等位酶水平的分析

本文采用水平淀粉凝胶电泳技术对分布于北京、山东和大连４个野生大豆天然居群共计１２０个体进行了等位酶水平遗传多样性分析。７个酶系统１３个等位酶位点的检测表明，该地区野生大豆天然居群遗传变异水平较高，多态位点比率Ｐ＝６９．２０，等位基因平均数Ａ＝１．７７，平均期望杂合度Ｈｅ＝０．１３３，居群间有较明显的遗传分化，基因分化系数Ｇｓｔ＝０．３９１，即有３９．１％的遗传变异存在于居群间。本文结果表明该地区遗     

中国栽培大豆代表品种和野生大豆部分群体脲酶等位酶的分析

用聚丙烯酰胺凝胶电泳方法分析了我国栽培大豆８２个代表品种和野生大豆部分群体的脲酶等位酶。本实验室条件下脲酶快带Ｒｆ＝０．５４－０．５９，慢带Ｒｆ＝０．３６－０．４３，与文献报道一致。所分析８２个品种快慢脲酶变异体约各半，各等位的分布与该品种的产地无上关性。在已分析的野生大豆群体中，也发现脲酶存在快带和慢带两种变异。所以大豆脲酶基因的突变可能发生在野生大豆的天然群体里。     

直播稻生产概况与品种选育策略

近年,直播稻面积在我国迅速扩大。本文结合国内外直播稻生产概况,指出了直播稻在抗倒伏、出苗率、耐冷性、防治杂草以及生育期等方面存在的问题,提出了培育“生育期适中、抗倒伏、耐低温、耐低氧萌发”的适合直播的水稻新品种选育策略。     

太湖地区水稻地方品种品质性状多样性研究进展

太湖地区种稻历史悠久,积累了丰富的水稻地方品种资源,水稻地方品种的遗传多样性研究可为优质资源的保护利用以及选育新品种提供一些参考。本文从遗传多样性的概念、研究方法、太湖地区水稻地方品种品质性状多样性研究进展等方面进行了综述,总结了太湖流域水稻地方品种资源的相关利用价值。     

广东常规稻主栽品种品质性状多样性演变分析

 为了解优质育种对品质性状多样性的影响,选取50份不同时期水稻品种来分析其品质性状多样性,并通过对品质性状进行聚类分析和主成分分析（PCA）来了解不同时期品种间的遗传关系。结果表明,1980年以前少数品质性状趋向优质,1980 至1994年期间大部分性状趋向优质,而1994至2008年全部性状都趋向优质。品质性状多样性一直处于下降状态,1994至2008年下降最剧烈。此外,随着时间推移,现代品种与地方品种的遗传差异在扩大。因此,在追求优质的同时,应注重保持水稻品种品质性状多样性和地方稻种资源的利用。     

应用形态、等位酶和SSR标记研究水稻矮仔占衍生品种的遗传差异

选取我国水稻矮仔占衍生品种24份,应用形态学、等位酶和微卫星(SSR)标记,分析矮仔占衍生品种的遗传差异。聚类分析表明3种方法在鉴别品种的遗传差异上存在较大差异。形态性状和SSR标记均能有效地鉴别24份衍生品种,而等位酶仅能鉴别其中17份。从形态学性状看,以香药糯与其他品种的遗传差异最大,SSR分析以香药糯、珍珠矮11和辐陆选与其他品种的遗传差异较大,而等位酶分析,则以团结1号与其他品种的差异最大。三类标记的遗传距离间虽存在有一定的相关性,但相关系数较小（0.217~0.494）,其中,形态学性状与SSR标记间相关极显著（r= 0.494,P= 0.002）,等位酶与其他两类标记的相关性均不显著。研究结果还表明,系统选育和辐射选育的品种与亲本间有可能存在较大的遗传差异。     

黑龙江省大豆推广品种农艺和品质性状优异等位变异的发掘

发掘推广品种的农艺和品质性状优异等位变异和载体材料可为培育优质大豆品种提供遗传信息和育种资源。本研究以200份黑龙江省近年大豆推广品种为试验材料,利用187对SSR标记进行全基因组扫描,分析群体结构,采用TASSEL软件的GLM方法对标记与3个农艺性状、蛋白质含量及油分含量进行关联分析。结果表明：10 个SSR标记与百粒重关联,其中表型效应值最大的优异等位变异为Sat-149-192,载体材料为东农57;8个SSR标记 与株高关联,表型效应值最大的等位变异是Satt413-206,载体材料为赤豆1号;13个SSR标记与生育期关联,表型 效应值最大的等位变异是Satt631-180,载体材料为黑农61;5个SSR标记与油分含量关联,表型效应值最大的等位 变异是Satt234-138,载体材料为合丰55;9个SSR标记与蛋白质含量关联,表型效应值最大的等位变异是Satt632- 293,其载体材料为东农43。上述等位变异的信息为培育提供了亲本选配和后代等位条带辅助选择的依据。     

“三明水晶稻”的性状及栽培技术

“三明水晶稻”的性状及栽培技术许旭明，张受刚，黄显波，余永安，谢小丹（三明市农科所沙县３６５５０９）三明水晶稻是三明市农科所用ＩＱ号／萌ｔ６３／／明ｉｅ６３杂交选育而成的优质高产水稻品种，经２年多点示范表现米质优。产量高、适应性广，一般亩产４００～５...     

Morphological Structure and Genetic Mapping of New Leaf-Color Mutant Gene in Rice (Oryza sativa)

Leaf-color mutations are a widely-observed class of mutations, playing an important role in the study of chlorophyll biosynthesis and plant chloroplast structure, function, genetics and development. A naturally-occurring leaf-color rice mutant, Baihuaidao 7, was analyzed. Mutant plants typically exhibited a green-white-green leaf-color progression, but this phenotype was only expressed in the presence of a stress signal induced by mechanical scarification such as transplantation. Prior to the appearance of white leaves, mutant plant growth, leaf color, chlorophyll content, and chloroplast ultrastructure appeared to be identical to those of the wild type. After the changeover to white leaf color, an examination of the mutated leaves revealed a decrease in total chlorophyll, chlorophyll a, chlorophyll b, and carotenoid content, a reduction in the number of chloroplast grana lamella and grana, and a gradual degradation of the thylakoid lamellas. At maturity, the mutant plant was etiolated and dwarfed compared with wild-type plants. Genetic analysis indicated that the leaf mutant character is controlled by a recessive nuclear gene. Genetic mapping of the mutant gene was performed using an F2 population derived from a Baihuaidao 7 × Jiangxi 1587 cross. The mutant gene was mapped to rice chromosome 11, positioned between InDel markers L59.2-7 and L64.8-11, which are separated by approximately 740.5 kb. The mutant gene is believed to be a new leaf-color mutant gene in rice, and is tentatively designated as gwgl.     

云南省不同地理位置水稻品种遗传多样性分析

在云南省的6个试验点收集了160个生产上使用的水稻(Oryzasativa)品种,用24对SSR引物对其进行遗传多样性分析,结果显示,24个标记都具有多态性,共检测到324个等位基因,每个多态位点检测到的等位基因数为7～20个,平均13.46个,总群体平均香农指数为2.0356,平均期望杂合度为0.8353。160个品种在相似系数0.101～0.996之间存在显著的遗传变异。AMOVA分析表明,水稻的遗传变异主要存在于地区内品种间(54%),只有7%遗传变异存在于地区间,品种内的遗传变异占39%。各试验点水稻品种遗传多样性分布不均匀,由高到低依次为:永德>元阳>石屏>保山>玉溪>石林。本研究结果表明,云南省水稻品种具有丰富的遗传多样性,但不同地理位置的水稻品种遗传多样性差异较大,这也为有效进行水稻种质资源的收集保存和利用模式提供了理论基础。     

一个水稻新型叶色突变体的形态结构与遗传定位

 所用水稻叶色突变体为自然突变,并命名为白淮稻7号,其叶色表型为绿 白 绿,且突变表型只有在移栽等因素引起的机械损伤信号胁迫下才会产生。研究结果表明,叶色转白前,突变体生长态势、叶色、叶绿素a含量和叶绿体超显微结构与野生型差异不大;叶色转白后,突变体总叶绿素、叶绿素a、叶绿素b和类胡萝卜素含量都显著低于野生型和叶色转白前,而叶绿体中的类囊体逐渐降解,基粒片层减少、基粒数量明显减少,且在成熟后突变体叶色黄化、植株变矮小。遗传分析表明,突变性状由1对隐性核基因控制。以该突变体与江西1587的F2群体为定位群体,将突变基因定位于水稻第11染色体分子标记L59.2 7和L64.8 11之间大约740.5 kb的区间内。认为该突变基因是一个新的水稻叶色突变基因,暂命名为GWGL。     

热带水稻优异种质资源的表型遗传多样性分析

有效管理和充分挖掘遗传多样性丰富的稻种资源对水稻育种具有重要意义。利用15个表型性状对来自9个热带国家和地区的127份热带水稻育种优异种质进行综合评价,比较分析不同来源热带水稻优异种质的表型差异和遗传多样性指数。结果表明：热带水稻种质资源表型性状差异明显,数量性状的变异系数为7.0%～23.8%,平均为12.04%,其中单株穗数比较大,谷粒长较小;Shannon-Wiener多样性指数分析结果表明,15个表型性状遗传多样性指数变化为0.603～2.066,平均为1.579,其中每穗总粒数比较高,穗型较小;9个不同来源地的热带水稻资源多样性指数为0.780～1.547,平均为1.219。不同来源的热带水稻种质各性状变异范围较大,各性状间存在显著差异,遗传多样性指数较高,可进一步发掘优异资源和有利基因,为培育和筛选优良热带水稻品种提供亲本来源。     

Genetic Diversity among Parents of Hybrid Rice Based on Cluster Analysis of Morphological Traits and Simple Sequence Repeat Markers

Heterosis has been successfully exploited on a large scale in rice (Oryza sativa L.), which is a self-pollinated crop. The selection of parental lines plays a vital role in developing ideal combinations. Therefore, it is essential to study the relationshi…     

A Comparative Study of SSR Diversity in Chinese Major Rice Varieties Planted in 1950s and in the Recent Ten Years （1995-2004）

Forty pairs of SSR markers were used to compare the genetic diversity changes in 151 Chinese major rice varieties planted in 1950s and in the recent ten years. Of 40 SSR loci, 39 were found to be polymorphic while one locus (RM479) monomorphic. A total of 213 alleles were identified from the 39 polymorphic loci. The average number of alleles per locus (Na) was of 5.5, ranging from 2 to 11. Nei’s gene diversity index (He) varied drastically among loci from 0.309 at RM174 to 0.869 at RM418, with an average value of 0.649. There existed significant difference in SSR allelic diversity between indica and japonica subspecies, and indica had more variation than japonica both in Na and He. By comparison with the genetic changes in Na and He, it was revealed that the varieties planted in 1950s had more alleles and higher He than those in the recent ten years both for indica and japonica rices. The difference between two subspecies for Na was significant in a tendency over time (indica: z = 2.677, P = 0.007; japonica: z = 3.441, P = 0.001), but not significant for He (indica: z = 1.471, P = 0.141; japonica: z = 1.932, P = 0.053). Analysis of molecular variance (AMOVA) indicated that there existed significant difference (P < 0.05) in genetic variation between the two periods, of which more genetic variation was contributed by indica (Fst = 0.050) and japonica (Fst = 0.082) subsets. Using locus-by-locus AMOVA procedure, significant genetic differentiations were observed in 13 loci (RM21, RM128, RM147, RM169, RM190, RM221, RM231, RM251, RM253, RM317, RM341, RM418, and RM478) for indica varieties and 11 loci (RM101, RM135, RM152, RM159, RM169, RM190, RM251, RM253, RM311, RM418, and RM478) for japonica ones between the two periods. It was found some alleles had been lost in current major rice varieties as comparing with those in 1950s. Therefore, it should be necessary to exploit more alien elite genetic resources for extension of genetic background in current rice breeding program.     

用SSR标记评估东北三省水稻推广品种的遗传多样性

 利用53个SSR标记和24个表型性状分析东北三省107个水稻推广品种,探讨东北水稻推广品种群体遗传多样性及不同育成年代、省份间的遗传多样性和互补性。结果表明,表型遗传多样性高于DNA水平,年代间表型与微卫星标记的遗传多样性具有较高的相似性,而地区间无明显相似性。东北水稻推广品种遗传多样性比较狭窄,随着时间推移增加的新等位基因多于消失的旧等位基因数。三省水稻推广品种遗传多样性呈现黑龙江>吉林>辽宁的趋势,但由于地区间频繁引种,东北水稻品种在区域上的遗传分化已不明显,其差异主要来源于品种间的基因型差异。不同省份存在较多的互补等位变异,最多的在黑龙江和辽宁之间。不同省份和不同年代间分别拥有各自特有和特缺的等位变异。参试品种可分为5个类群,每一类群均有两个以上年代（省份）品种分布。     

Genetic Diversity and Population Structure in Landraces and Improved Rice Varieties from India

A set of 50 rice genotypes comprising landraces, local selections, and improved varieties were characterized using simple sequence repeat(SSR) and inter simple sequence repeat(ISSR) markers to study genetic diversity and population structure. Following unweighted pair group method with arithmetic mean based clustering using binary data of polymorphic markers, the genotypes were grouped into 5 clusters and 11 sub-clusters, whereas population structure analysis separated 50 rice genotypes into 5 sub-populations. Grouping of rice genotypes showed better resemblance with the pedigree information of the genotypes. Both genetic diversity and population structure analysis separated majority of the improved varieties from landraces and local selections. Some of the SSR markers amplified unique alleles which were specific to a particular genotype and could distinguish them from the rest. The results indicate that these rice genotypes exhibit a higher genetic diversity and can be very useful in rice improvement program.