啤酒大麦与饲用大麦籽粒结构和淀粉粒的比较研究

为了探索大麦籽粒结构和淀粉粒与其用途的关系，利用扫描电子显微镜（SEM）和差示扫描量热分析仪（DSC）对啤酒大麦（港啤1号和扬农啤2号）与饲用大麦（扬饲麦1号）的籽粒结构和淀粉粒进行了比较研究。结果表明，3个品种表现相似的胚乳结构，但啤酒大麦的淀粉粒与蛋白质结合不紧密，饲用大麦的淀粉粒和蛋白质结合较紧密，且饲用大麦的蛋白质基质含量高于啤酒大麦。采用碱处理和差速沉淀法分离了籽粒胚乳大、中、小淀粉粒，虽然品种间淀粉粒的形态无明显差别，但大、中、小淀粉粒的大小和含量差异很大。DSC分析所得参数表明，大淀粉粒糊化时的起始温度（To）、峰值温度（Tp）和终结温度（n）高于相同品种的中、小淀粉粒，且糊化过程所需的热焓（△H）也较高。     

Genetic Control of Quantitative Grain and Malt Quality Traits in Barley

Abstract

Many of the important determinants of barley grain and malt quality exhibit quantitative variation and are affected by both genetic and environmental factors. In recent years, the application of molecular marker techniques has permitted the detection and mapping of quantitative trait loci (QTL) for grain and malt quality traits in many populations. Here, the quantitative traits affecting the grain and malt quality of barley grain are reviewed, and results from two analyses of grain and malt quality data from barley mapping populations (a multi-variate analysis of interrelationships among traits and a comparative analysis of QTL positions and effects among five populations) are presented and discussed.     

Mapping quantitative trait loci using the marker regression and the interval mapping methods

The marker regression and the interval mapping methods were used for the detection of qualitative trait loci (QTL) in Arabidopsis thaliana in a cross between early flowering ecotypes Landsberg erecta and Columbia. The interval mapping method employs pairs of neighbouring markers to obtain maximum linkage information about the presence of a QTL within the enclosed segment of the chromosome, whereas the marker regression approach fits a model to all the marker means on a given chromosome simultaneously and obtains significance tests by simulation. The interval mapping method detected 22 QTL in seven traits and the marker regression method detected 22 QTL in six traits. The two methods detected sixteen QTL at similar positions of the Arabidopsis chromosomes and QTL for similar traits were localised to similar regions of the chromosomes and they showed similar mode of additive effect. This suggested that the two methods are similar in their QTL detection even though they employed different significant levels.     

基于温热BC1群体的农艺性状QTL定位

利用昌7-2与热带自交系CML451构建的BC₁群体开花期、株高以及产量相关性状进行QTL定位分析。通过复合区间作图方法共检测到与散粉期、抽丝期、株高、穗位高、穗长、穗粗、穗轴粗、穗行数8个性状相关联的QTL 26个。控制散粉期的qDTP5被定位于第5染色体上的umc1523-bnlg1660标记区间,其解释了16%表型变异;控制株高的qPH3被定位于第3染色体上的bnlg1798-bnlg1852标记区间,解释了19.9%表型变异;控制穗位高的qEH10-2被定位于第10染色体上的umc1911-bnlg594标记区间,解释了13.4%表型变异;控制穗长的qEL10-2被定位于第10染色体的bnlg1250-bnlg594区间,解释了13%表型变异;控制穗粗的qED5、控制穗轴粗的qCD5、控制穗行数的qER5均被定位于第5染色体上的bnlg1660-bnlg1208区间,分别解释了18.1%、11.3%与21.8%表型变异;qED7定位于第7染色体上的umc1154-umc1799区间,与穗粗相关,解释了21.9%表型变异。     

大麦2H染色体对小麦农艺和品质特性的影响

为了研究2 H染色体对小麦农艺和品质特性的影响,测定了普通小麦中国春(CS)、栽培大麦Betzes及其杂种衍生的二体异附加系CS 2H和3个异代换系2H/2A、2H/2B、2H/2D的农艺性状及籽粒硬度、蛋白质组成、淀粉特性.结果表明,2H附加系和代换系的农艺性状比CS都有不同程度的改善,但不育小穗数增加,不育率提高,以2H/2A的不育率最高(40.4%).籽粒硬度仅2H附加系表现超亲,三个代换系则介于双亲之间.含2H染色体材料的蛋白质、总氨基酸、苏氨酸和赖氨酸含量、沉淀值均表现超亲遗传,尤以2H/2A的超亲优势最大.3个异代换系的直链淀粉含量均低于双亲,以2H/2A的含量最低;2H/2B的降落值介于双亲之间,其余均超亲,以2H/2A最高.三个代换系的峰值粘度、最终粘度都超亲,稀懈值介于双亲之间.2H/2A在这些淀粉品质指标中表现出了最好的遗传正效应.     

小麦产量性状的QTL分析

为寻找更多与小麦产量性状相关的数量性状位点（QTL）,利用江苏地方品种望水白与墨西哥小麦品种Alondra杂交构建的重组自交系群体（104个家系）,在3个试验环境下进行了单株有效穗数、主穗粒数、单穗粒数和千粒重4个性状的QTL分析,结果在5A染色体上检测到与单株有效穗数相关、可以解释10．3％～18．8％表型变异的QTL1个;检测到与主穗粒数相关的QTL8个,分别位于染色体1B、1D、3B、4A、5D、6B上和连锁群4上（未知具体染色体归属）,单个QTL可以解释9．9％～19．9％的表型变异;检测到与单穗粒数相关的QTL11个,分别位于染色体1B、1D、2A、2B、3B、4A、5D、6B和7A上,单个QTL可解释7．5％～43．4％的表型变异;检测到与千粒重相关的QTL5个,分别位于2A、2B、3B、4D和7A染色体上,单个QTL可解释9．6％～25．7％的表型变异。获得的QTL可以用于分子标记辅助育种。     

Grain composition of Virginia winter barley and implications for use in feed,food, and biofuels production

Grain compositional components impacting barley (Hordeum vulgare L.) use in food, feed and fuel products, must be combined with improved agronomic traits to produce a commercially viable barley cultivar. Little current information is available on grain composition and variability among winter barley genotypes. This study was conducted to determine the variability among modern hulled and hulless winter barley genotypes in grain composition. Barley types varied significantly in grain and kernel weight, starch, beta-glucan, oil and ash content, but not in protein concentration. Hulless barley had significantly higher grain test weight and starch concentration than hulled and malting types, and significantly higher beta-glucan than malting barley. Hulless barley had significantly lower kernel weights, oil, and ash concentrations than hulled and malting types. Higher starch and lower fiber and ash in grain of hulless barley versus hulled feed or malting type barley are characteristics that increase hulless barley desirability. Selection for high starch concentration among all barley types is feasible and will facilitate development of barley cultivars better suited for use in feed, malt, and ethanol production.     

小麦粒形QTL元分析及候选基因预测

粒形是影响小麦籽粒产量和品质的重要参数,是由多基因控制的复杂数量性状。为发掘控制小麦粒形相关的真实主效数量性状位点(quantitative trait loci, QTL),本研究利用BioMercator 4.2软件,以小麦高密度分子标记遗传图谱为参考图谱,对来自不同遗传作图群体的113个控制小麦粒长的QTL和86个控制粒宽的QTL进行图谱整合、映射以及QTL元分析。通过建立QTL一致性图谱,获得18个控制小麦粒长和8个控制粒宽的一致性QTL(meta quantitative trait loci, MQTL)位点,置信区间最小可达到0.57 cM,主要分布在2B、2D、3A、3B、4B、5A、5B和7D染色体上。在5A染色体Xgwm293～Xgwm304和Xgpw2120～Xgpw2273a标记区间内,预测到7个与小麦粒长和粒宽相关的候选基因。本研究为小麦粒形QTL精细定位以及分子标记辅助选择育种提供理论依据。     

玉米主要营养品质性状的QTL定位

以LX00-6×E28的278个F_2:3家系为作图群体,通过SSR标记利用MAPMAKER/EXP3.0和Mapdraw 2.0构建遗传连锁图谱.该连锁图覆盖玉米基因组1 508.1 cM,包含124个标记,相邻两标记的平均距离为12.2 cM.利用QTLMaper2.5软件,结合主要品质性状的检测结果,运用复合区间作图法,以LOD=2.0对玉米主要品质性状进行全基因组QTLs扫描,检测到两个与淀粉含量相关的QTL位点,分别位于第1、8条染色体上,表现为部分显性效应和加性效应,并在第1条染色体上检测到1个与油分含量相关的位点,表现为加性效应.     

水稻第6染色体短臂株高及产量性状QTL的分解

针对第6染色体短臂上一个对产量性状遗传具有重要作用的区间RM587-RM19715,从珍汕97B/密阳46重组自交系群体中筛选到1个剩余杂合体,自交衍生获得一个由195个个体组成的F2群体,检测控制株高和产量性状的QTL。经分析,在目标区间的上部和下部分别检测到1个QTL簇,分别对除单株穗数以外的产量性状因子具显著作用,单个QTL对群体性状表型变异的贡献率为5.0%~55.5%。将第6染色体上的产量性状QTL分解到更小的区间中,为产量性状QTL的精细定位和克隆打下了基础。     

西藏冬青稞胚乳淀粉粒发育特征研究

为了解青稞胚乳淀粉及淀粉粒形成与生长特征,以西藏育成青稞品种冬青8号为材料,对籽粒发育过程中胚乳灌浆速度、淀粉积累量及淀粉粒的产生、二维面积、粒径变化进行了分析。结果表明,胚乳发育过程中,干物质和淀粉积累量呈S型曲线,两者呈正相关。花后5d,青稞胚乳中可零星见到粒径和二维面积较小的A型小淀粉粒;花后10~15d,A型小淀粉粒数量显著增大,但粒径和二维面积增加较慢;花后20d,B型小淀粉粒可能已经形成,与A型小淀粉粒组成一个复合群体;花后25d,形成了粒径10μm的A型淀粉粒、粒径5~10μm的B型淀粉粒和粒径5μm的C型淀粉粒;花后30~55d,不同粒径的淀粉粒数量和二维面积逐渐增加,其中,C型淀粉粒数量不断增加直至籽粒成熟。青稞成熟籽粒胚乳中,淀粉粒的粒径为1.45~44.76μm,二维面积为3.56~1 750.8μm2;A型淀粉粒形状为近圆形,表面光滑,个别表面附着有C型淀粉粒,B型淀粉粒形状有近圆形、椭圆形多种类型,C型淀粉粒形状比B型淀粉粒的变异更大。     

六棱大麦抗赤霉病QTL的定位(英文)

赤霉病是最严重的大麦病害之一。由于赤霉病抗性是受多基因控制的数量性状(QTL),并且一些表型性状也影响大麦赤霉病的抗病,如棱数、株高和抽穗期等,所以抗赤霉病大麦品种的选育十分困难。为了明确加拿大六棱大麦中赤霉病抗性以及相关性状的QTLs,本研究在4年中对93个家系的DH作图群体中赤霉病抗性、呕吐毒素(DON)含量、株高、抽穗期和成熟期等相关性状进行调查,并利用分子标记(444个DArT和26个SSR标记)构建的连锁图谱对QTL开展复合区间作图。结果表明,本研究共检测到4个影响赤霉病的QTLs,其中,2个主要的QTLs定位在3H和7H染色体上,它们的加性效应为-3.44和-3.69,分别解释14.1%和17.5%的表型差异,总共解释31.6%的赤霉病抗性差异;另外2个QTLs定位于7H染色体上,但二者同时也与DON含量显著相关。此外,在3H、5H和7H染色体上确定了5个影响株高的QTLs,在2H、4H、5H和7H上确定了4个影响抽穗期的QTLs。同时发现2个赤霉病抗性QTLs和1个DON累积QTL与控制株高的QTLs聚集重叠,1个赤霉病抗性QTL和抽穗期QTLs重叠。这些与赤霉病抗性、株高及抽穗期等农艺性状紧密连锁的分子标记可进一步用于有效提高抗赤霉病大麦品种的选育效率。     

利用不同群体对玉米株高和叶片夹角的QTL分析

应用H21×Mo17、自330×K36、B73×L050这3个F23∶群体为作图材料,利用SSR等分子标记,对株高、穗位高和叶片夹角3个性状进行了数量性状位点(QTL)分析。对株高共检测到18个QTL,对穗位高检测到12个QTL,对叶夹角检测到9个QTL。在这些影响不同性状的QTL中,有一部分处于染色体上的同一区域,有的则是区域间部分重叠或处于邻近区域。此外,有的QTL还与其他研究中发现的影响相应性状的质量性状基因位点处于相同基因组区域。     

QTLs for malting flavour component associated with pre-harvest sprouting susceptibility in barley (Hordeum vulgare L.)

Lipoxygenase (LOX) is a key factor affecting quality of beer in terms of foam stability and flavour. Low LOX content is a desirable trait for malting quality. A doubled haploid (DH) population was made from a cross of Australian malting barley Stirling and Canadian malting barley Harrington and mapped with 513 molecular markers. The 120 DH lines with their parents were planted in field trials and the harvested grains were micro-malted for analysis of LOX content in two consecutive years. LOX content was controlled by both genetic effects and environment conditions. Three QTLs were consistently detected. One QTL flanked by the markers E6216 and SCssr03907 at the telomere region of chromosome 5HL contributed 39% of genetic variation in LOX content. The second QTL close to the centromere region of chromosome 5H accounted for 17% of genetic variation. A minor QTL on chromosome 2H explained 6% of genetic variation but was significant in both years. The Australian variety Stirling contributed to higher LOX content for the three QTLs. The two QTLs mapped at chromosome 5H for LOX content coincided with the QTLs for seed dormancy/pre-harvest sprouting from the same population. The pre-harvest sprouting susceptible alleles were associated with low LOX content, which indicated that the low LOX QTL from the Canadian malting barleys are only useful in the barley growing areas where the pre-harvest sprouting risk is low. New genetic sources for low LOX should be exploited in different germplasm with different mechanisms.     

小麦旗叶与幼苗性状的QTL分析

为挖掘控制小麦幼苗性状与旗叶性状的QTL,并探讨两者的遗传基础,以京冬8号和矮抗58构建的RIL群体(207个家系)为材料,田间试验测定旗叶相关性状,水培试验测定幼苗期相关性状,通过完备区间作图对这些性状进行QTL研究.结果共检测到10个控制旗叶性状的QTL,单个QTL可解释1.98％～9.89％的表型变异,其中有6个...     

不同氮水平下玉米子粒品质性状的QTL定位

以优良玉米自交系许178×K12杂交衍生的包含150个家系的重组自交系群体为试验材料,在正常施氮和不施氮两种条件下,对玉米子粒品质性状(蛋白质、淀粉和油分)进行表型鉴定,利用最佳线性无偏预测法结合2年的表型数据,估计各家系各性状在不同氮水平下的育种值。利用QTL IciMapping V4.0软件的完备区间作图法(ICIM)对3个性状进行QTL检测,在两种氮水平下共检测到14个品质性状相关QTL位点,其中,正常施氮条件下检测到8个QTL,不施氮条件下检测到6个QTL。2个QTL可以同时在两种氮水平下被检测到,其受环境因素影响较小,可以在玉米子粒品质分子育种上应用。在不施氮条件下共发现4个特异表达的QTL,其可能应用于低氮条件下玉米品质改良研究。     

Influence of environmental temperature during grain filling period on granule size distribution of rice starch and its relation to gelatinization properties

High temperature (HT) is the major environmental factor affecting grain starch properties of cooking rice cultivars. However, little information has been available on the effect of environmental temperature on the starch granule size distribution of rice grains. In this paper, five indica rice genotypes, including the wild type (9311) and its four mutants differing in amylose content (AC), were used to investigate the effect of environmental temperature on the starch granule size distribution, as well as its relation to AC and gelatinization properties of rice starch. Two temperature treatments (HT and NT) at filling stage were imposed to rice plants under the controlled temperature chambers. The result showed that HT increased the average diameter of starch granules and enhanced the proportion of large starch granules (LSG, D > 2.6 μm) by number, volume and surface area, respectively. However, influence of HT on GT and starch granule size distribution was relatively independent of their alteration in AC level for different rice genotypes. Therefore, HT-induced increase in the average diameter of starch granules and LSG percentage was strongly responsible for the higher starch gelatinization temperature and inferior cooked palatability of HT-ripening rice grains, which be not inherently associated with their varying AC level.     

三个小麦赤霉病抗源的抗性QTL定位

为寻找小麦赤霉病抗性基因及可用于分子标记辅助育种的抗性连锁标记．对中国的三个小麦赤霉病抗源苏麦3号、望水白和宁894037进行了抗性QTL的定位研究。SSR、AFLP分析与QTL分析结果表明,尽管三个抗源的来源和遗传背景并不同,但均在3B染色体短臂上发现抗性主效QTL,不同遗传群体所获得的QTL位点所处的染色体区段略有差异,位于QTL两翼的SSR标记也有所不同。苏麦3号的赤霉病抗性主效QTL位于3B染色体上的标记区间Xgwm533～Xgwm493内;宁894037的抗性位点分布于3B和6B染色体上。分别定位于标记Xgwm493～Xbarcl33和Xgwm644-Xgwm518之间;望水白的抗性主效QTL也位于3B染色体上．定位于标记Xgwm493～Xbarc147之间。微效QTL由于遗传群体的不同,分别住于1B、3B和2A染色体上。研究还表明,寻找抗性QTL在3B染色体以外的新抗源十分必要。     

基于遗传位置的水稻与玉米重要农艺性状QTL比较研究

 收集整理了水稻与玉米15个共有性状已发表的QTL定位信息,依据QTL遗传位置信息整合遗传图谱,开展了水稻与玉米基因组QTL水平的比较研究工作。结果表明：1）任一性状QTL的定位频率在染色体上的不同区域内是不同的,存在着若干“热点区域”。QTL定位频率较高的区域,往往能够反映不同遗传背景、不同环境条件下这一区域对特定性状的强表达。在这些区段内,有较高的概率找到控制这一性状遗传率较高的QTL。2）几个不同性状QTL的热点区域常常发生重合,这可能是控制不同性状的基因在染色体上密集排列紧密连锁成一个基因簇造成的;也可能是一个基因影响了多个性状,即一因多效的结果。这些同时对几个性状产生影响的活跃区域,对作物的遗传改良有较大利用价值。     

藁城8901与豫麦50籽粒淀粉粒的粒度分布特征

为研究小麦籽粒发育过程中胚乳淀粉粒形成与粒度分布特征,以小麦品种藁城8901与豫麦50为材料,研究了籽粒胚乳淀粉粒形成、生长与分布特征。结果表明,花后4d,小麦胚乳出现不同范围大小的淀粉粒,最大粒径8μm。花后7d,籽粒中淀粉粒增多增大,最大粒径20μm左右。花后10~14d,淀粉粒体积继续增大,并产生了一个新的小淀粉粒群体。花后17d,淀粉粒以体积增大为主。花后21d,淀粉粒最大粒径较成熟期变化较小。花后24d,小于0.6μm的淀粉粒数目急剧增加,大于0.6μm的淀粉粒数目占比则明显减少,表明这一时期又产生了一个新淀粉粒群体(后期形成的B型淀粉粒)。花后24~28d,小于0.6μm的淀粉粒数目仍不断增加,而直径较大的淀粉粒数目增加减少,表明籽粒中新淀粉粒的产生仍在继续,但以小粒径淀粉粒为主。花后28d至成熟期,最小粒径淀粉粒进一步生长,其他淀粉粒粒径变化相对较小。