小麦主要显性矮源致矮力及遗传分析

选用7个显性矮源与11个普通小麦品种按不完全双列杂交,研究显性矮源对株高的致矮能力及遗传效应。结果表明：矮变1号致矮能力最强,奥尔森,矮苏3和西农02致矮能力较强,BAU-Rht21,BUA-Rht12和西农10的致矮能力较弱;西农02的致矮能力与奥与森,矮苏3相当,与矮变1号的致矮能力差异极显著,其致矮能力比矮变1号大为减弱,西农02不同于矮变1号,显性矮源所配组合F1代株高的狭义遗传力和广义遗传力都比较高,F1代株高主要受加性效应的影响,各显性矮源的加性效应值均为负效应,杂交父本的加性效应值除了91-27亲本的加性效应值为负效应外,其他亲本的加性效应值均为正效应;各个显性矮源F1代株高与杂交父本株高的相关系数均达显著或极显著相关,根据回归方程的预测,除了矮变1号以外,其他显性矮源F1代株高均可达到理想株高。     

用近等基因系研究小麦显性矮源对主要经济性状的影响

为了筛选有利于育种的显性矮秆基因,利用5个普通小麦品种与5个不同显性矮源杂交回交6代以上产生的5套近等基因系,研究显性矮源对株高、株粒重、株有效穗数、穗粒数、千粒重、株粒数和穗重的影响。结果表明：显性矮源近等基因系之间的株有效穗数差异不显著外,其它性状差异极显著。5个显性矮源近等基因系都显著降低轮回父本(CK)的株高、千粒重、穗重,但具有西农引06、奥尔森和西南02矮源近等基因系的株高极显著高于矮苏3和矮变1号矮源近等基因系的株高,具有西南02和奥尔森矮源近等基因系的穗重显著高于其它矮源,具有奥尔森和西南02矮源近等基因系的千粒重亦高于其它矮源。具有奥尔森矮源近等基因系的株粒重与轮回父本没有显著的差异,其次是西南02矮源近等基因系;具有西南02矮源近等基因系的穗粒数与轮回父本没有显著的差异,其它都显著或极显著低于轮回父本的穗粒数;具有西农引06、奥尔森、西南02和矮苏3矮源近等基因系的株粒数与轮回父本间没有显著的差异,只有矮变1号矮源近等基因系极显著低于轮回父本。根据欧氏距离的聚类分析,具有奥尔森和西南02矮源近等基因系与轮回父本之间的距离最近,这有利于育种应用,矮变1号矮源近等基因系的距离最远,难以直接应用于育种;西农引06矮源和矮苏3矮源最近,西南02矮源和矮变l号矮源最远;用系统聚类,西农引06、矮苏3、奥尔森、西南02矮源为部分显性类,父本和矮变1号矮源各为一类。     

小麦主要显性矮源致矮力及遗传分析

选用7个显性矮源与11个普通小麦品种按不完全双列杂交,研究显性矮源对株高的致矮能力及遗传效应.结果表明:矮变1号致矮能力最强,奥尔森、矮苏3和西农02致矮能力较强,BAU-Rht 21、BUA-Rht 12和西农10的致矮能力较弱;西农02的致矮能力与奥尔森、矮苏3相当,与矮变1号的致矮能力差异极显著,其致矮能力比矮变1号大为减弱,西农02不同于矮变1号.显性矮源所配组合F1代株高的狭义遗传力和广义遗传力都比较高,F1代株高主要受加性效应的影响.各显性矮源的加性效应值均为负效应,杂交父本的加性效应值除了91-27亲本的加性效应值为负效应外,其他亲本的加性效应值均为正效应.各个显性矮源F1代株高与杂交父本株高的相关系数均达显著或极显著相关,根据回归方程的预测,除了矮变1号以外,其他显性矮源F1代株高均可达到理想株高.     

20个小麦矮源的致矮力及聚类分析

用20个矮源作母本测配的F1代株高,研究矮源的致矮力及其与父本的关系,结果表明：致矮能力强的显性矮源有矮变1号、绵11RhI3和黄抗Rht 10;致矮能力较弱的隐性矮源有农林10、贵农40、渝46和84-2014;致矮能力较强的半显性矮源有13个矮源。矮源F1代株高与杂交父本株高的相关系数和回归方程达极显著,对父本株高降幅较大的矮源有矮变1号、绵11Rht3和黄抗Rht0,降幅较小的矮源有渝46、84-2014、贵农40、农林10和西南06;其他12个矮源影响适中,是杂交小麦育种首先考虑应用的矮源。聚类分析表明矮变1号为Ⅰ类,绵11 Rht3和黄抗Rht 10为Ⅱ类,BAU-Rht 12为Ⅲ类,矮苏3、奥尔森、西南02、西南04、西南04-1、西南05、BAU-Rht 21、西南06、西南07、渝183、渝172、早农林10为Ⅳ类,农林10、渝46、84-2014和贵农40为Ⅴ类。     

20个小麦矮源的致矮力及聚类分析

用20个矮源作母本测配的F1代株高,研究矮源的致矮力及其与父本的关系,结果表明:致矮能力强的显性矮源有矮变1号、绵11Rht 3和黄抗Rht 10;致矮能力较弱的隐性矮源有农林10、贵农40、渝46和84-2014;致矮能力较强的半显性矮源有13个矮源.矮源F1代株高与杂交父本株高的相关系数和回归方程达极显著,对父本株高降幅较大的矮源有矮变1号、绵11 Rht 3和黄抗Rht 0,降幅较小的矮源有渝46、84-2014、贵农40、农林10和西南06;其他12个矮源影响适中,是杂交小麦育种首先考虑应用的矮源.聚类分析表明矮变1号为Ⅰ类,绵11 Rht 3和黄抗Rht 10为Ⅱ类,BAU-Rht 12为Ⅲ类,矮苏3、奥尔森、西南02、西南04、西南04-1、西南05、BAU-Rht 21、西南06、西南07、渝183、渝172、早农林10为Ⅳ类,农林10、渝46、84-2014和贵农40为Ⅴ类.     

小麦近等基因系的构建及应用进展

[目的]概述小麦近等基因系的构建方法及其应用进展,为近等基因系的合理利用提供参考。[方法]介绍了多代回交转育、基于目标性状位点杂合个体自交和从突变体中分离等构建小麦近等基因系的方法,阐述了近等基因系在小麦多系品种培育、抗病机制研究和品质基础研究等方面的应用,并展望了其应用前景。[结果]近等基因系是研究单个基因效应、克隆目标基因、基因精细定位及分子标记辅助育种的理想材料,随着小麦不同性状近等基因系的不断培育,其将有更广泛的应用。[结论]该研究为小麦近等基因系的构建及其进一步的合理利用提供了参考。     

小麦显性矮秆基因复等位多态特性研究

 世界小麦矮化育种主要使用隐性矮源。在普通小麦中发现的显性矮源均因导致植株极度矮化（20~55　cm）而未能在小麦育种中广泛应用。笔者发现,将显性矮源矮变1号（4DS携带Rht10,25~30 cm）及矮苏3（4BS携带Rht3,55 cm）的原种大群体种植或施以诱变因子并将其与中、高秆的小麦品种杂交、回交,从其分离世代的大群体中,均可选择到一些株高呈不同程度提升的稳定的突变株系。采用近等基因系法对不同株高突变衍生系的研究表明：其提升的株高真实遗传,各自均携带一个不同株高的半显性矮秆基因,随突变衍生系株高的提升,近等基因系的产量性状显著优化。采用标志基因测交法以及生理生化遗传标记对突变衍生系携带的不同株高的半显性矮秆基因重新进行了基因定位,确认它们分别与Rht10及Rht3的座位相同,因而均是其突变衍生的复等位基因。提出显性矮秆基因具有"复等位多态特性",即极度矮化的显性矮秆基因容易突变为一群株高提高程度不同的、可以达到小麦育种理想株高的半显性矮秆复等位基因。     

小麦抗叶锈近等基因系的利用及评价

本文对以Thatcher为遗传背景的近等基因系间的相似程度及其原因进行了综述,对近等基因系的利用及存在的问题进行了讨论。     

近等基因系在育种研究中的应用

介绍了近等基因系的构建方法及其在农作物和其他物种育种中的应用。     

Studies of Multi-Allelic Polymorphism of Dominant Dwarfing Genes in Wheat

Dwarfing breeding of wheat in the world is confined to the exploitation of recessive dwarfing sources. None of the dominant dwarfing sources discovered in common wheat (Triticum aestivum L. ) has found wide exploitation in wheat breeding due to the extreme dwarfness of their plants (20 -55 cm). We found in our work that some stable mutant lines with their plant height enhanced to different extents could be obtained in large populations derived from the stock seeds of the dominant dwarfing sources Aibian1 carrying Rht10 on 4DS and being 20 - 55 cm tall and Aisu2 carrying Rht3 on 4BS and being 55 cm tall, or from their descendants of induced mutation treatments, or from the segregating descendants of their crosses with mid- or tall-statured genotypes. Subsequently, we studied these mutation-derived lines differing in plant height with near isogenic lines and observed that the character of their enhanced plant height bred true, each carrying a semidominant dwarfing gene for a definite height and that as the plant height of the mutation-derived lines increased, the yield-contributing characters of their near isogenic lines were significantly improved. When test crosses with marker genes and physiological and biochemical genetic marker tests were performed to re-localize the semi-dominant dwarfing genes carried by the mutation-derived lines, it was confirmed that they shared common loci with Rht10 and Rht3 and that they were all mutation-derived multiple alleles. It is thus speculated that dominant dwarfing genes are of "multi-allelic polymorphism". In other words, dominant dwarfing genes, which are ultra-dwarfing, are liable to develop by mutation into a group of multiple alleles with plant height enhanced to different extents and some may have a height close to the ideal plant height for wheat breeding. Therefore, these results offer a fundamentally new approach for the exploitation of dominant dwarfing sources in wheat breeding.     

Expansin Genes Expressed Differentially in Peduncle Elongation of Near- Isogenic Wheat Rht Lines

The introduction of reduced height （Rht） genes Rht-Blb and Rht-Dlb led to impressive increases in wheat （Triticum aestivum L.） yields during the Green Revolution. In the present study, the dynamic elongation of peduncle in a set ofnear-isogenic lines （NILs） carrying different Rht alleles （Rht-Blb, Rht-Dlb, Rht-Blc, Rht-Dlb＋Rht-Blb, and Rht-Dlb＋Rht-Blc） were investigated. The reduction of the final length of peduncle in NILs was dependent mainly on the elongation rate, which was reduced by Rht genes, during rapid elongation phase. Resin sections showed that Rht genes strongly reduced the cell extension in peduncle. The expression of expansin genes, which mediate cell wall loosening and leading to cell expansion, were analysed by using real- time quantitative PCR （qPCR）. Among the 23 possible wheat expansin genes, 17 were expressed in the peduncle. The spatial distribution of expression was further analysed for five expansins that showed high expression levels in the peduncles of Rht lines. Compared to wild type plants, the incorporation of Rht-Dlb allele decreased about 37 and 80% of the expression levels of ExpA 7 and ExpA3 in elongation zone, respectively. The presence Rht-Blc dwarfing genes, however, produced 53% reduction in the expression level of ExpA7, and seriously decreased about 70% of ExpB9 expression. Although the expression levels of five genes exhibited variability among the lines, an expansin gene, ExpB2, showed its expression level highly associated with the cell elongation rate in peduncle of different Rht lines.     

The Value of Different GA Insensitive Rht Dwarfing Genes in Winter Wheat Breeding

The value of different dwarfing genes in winter wheat breeding was studied using 6 nearisogenic lines carrying different Rht dwarfing genes over three years experiment.Results showed that both the Rhtl and Rht2 semi-dwarfing genes had significantly positive effects on kernel number and grain weight per spike, and had significantly negative effects on 1 000-grain weight comparing to the tall line(rht) and the Rht3 line.The Rht3 dwarfing gene had a significantly negative effect on kernel number per spike,and had positive effect on 1 000-grain weight. The combination of the Rht2 and Rht3 gene showed significantly negative effect on yield components. All of these 5 dwarfing or semidwarfing genotypes mentioned above had a significantly negative effect on plant height and no significant effect on the area of flag leaf, spikelets per spike and spike length.     

Rht-B1b,Rht-D1b,Rht-B1c小麦矮秆基因及其互作对小麦农艺性状的影响

利用2套近等基因系,在人工模拟气候室,研究了不同Rht近等基因系营养性状的遗传差异.结果证明:Rht-B1b和Rht-D1b矮秆基因系不但具有很好的降秆作用,而且可以在生长前期形成较多的干物质和较坚硬的秆子,为后期籽粒产量的形成奠定基础;Rht-D1b半矮秆基因根系长度明显长于其它基因系,可能较其它基因系具有较强的耐旱能力;Rht-B1c基因系的分蘖数量及次生根或总根发生量多于其它基因系,无论苗高或株高均显著低于其它基因系,可在单纯的提高单株分蘖或次生根生长量及降秆为目的的育种中发挥一定作用.     

小麦矮秆种质山农矮330的农艺性状与矮化特性研究

调查分析了山农矮330的综合农艺性状及矮秆遗传特点。结果表明,山农矮330成穗能力强,小穗数多,结实性好,穗粒数多,且综合抗病性较好;携带一对不完全显性矮秆基因,对赤霉酸反应敏感,用其作矮秆亲本时致矮率在20％-30％,对后代的产量性状无明显的不利影响,其矮秆基因的表达受不同遗传背景的影响。     

河北省主要小麦育成种矮源研究

利用赤霉酸敏感性测定和系谱追踪方法，对河北省历年来培育的主要冬小麦品种的矮秆基因进行了鉴定分析。结果表明：７０．８％的品种的矮秆基因来自农林１０号；２２．２％的品种的矮源为赤小麦；６．９％的品种的矮源为郑引１号。５２．４％的河北省定名品种的矮秆基因来自赤小麦。部分品种的矮源还不清楚。     

五个部分显性矮秆小麦亲本的杂种优势和配合力分析

对５个部分显性矮秆小麦的杂种优势分析表明，半矮秆杂种小麦存在明显的产量优势，其中具有正向超亲效应的组合占７６％，超亲优势平均为１１．８％，以本地推广品种小偃６号为对照，超标组合为１００％，超标优势平均２４．８６％，以新育成品种陕２１３为对照，超标组合为４８％，平均超标优势８．７５％；对产量构成因素的分析表明，超亲优势大小次序为穗粒数＞千粒重＞穗数。穗粒数优势较强是半矮秆杂种小麦的一个特点。对８个农艺性状配合力的分析说明，０００４和５７４６配合力最好，其次为７５３９－２和矮特早。     

水稻灌浆期耐热性近等基因系的选育研究

在广泛搜集、耐热性筛选与鉴定的基础上．从大量的品种资源中选择对灌浆期高温胁迫耐性很强的早籼纯系品种“BG33-2”作供体亲本,灌浆期耐热性敏感的早籼纯系品种“赣早籼38号”为轮回亲本．经过9年11个世代的杂交、连续单株鉴定选择与回交、花药培养、连续自交．育成了一套赣早籼38号近等基因系。33个特征特性的鉴定及性状测定值的统计分析结果表明,本研究育成的G38HT、G38MT、G38HS其性状均已纯合稳定,灌浆期耐热性分别为高抗、中抗、敏感,这3个纯系是灌浆期耐热性有显著差异的赣早籼38号近等基因系。这套近等基因系可为进一步深人系统地探明水稻灌浆期耐热性的生理机制和遗传机理．提供理想的实验材料。     

现代近红外光谱分析技术在小麦领域的应用

阐述了现代近红外光谱分析技术的原理,介绍了近红外光谱分析技术在当前小麦品质育种、生产加工、籽粒和病害识别、抗性鉴定及网络品质监测技术方面的应用进展,并展望了未来的应用前景。