【作者】 刘伟；

【导师】 曹连莆； 刘广田； 李卫华；

【作者基本信息】 石河子大学 ， 作物遗传育种学， 2005， 硕士

【摘要】 品质改良是小麦育种的重要研究领域,等位基因变异对普通小麦品质性状的影响是主要通过改变谷蛋白大聚合体(GMP)含量来实现的,GMP与沉淀值及面包体积等品质性状的相关性极显著。关于GMP积累动态变化规律以及GMP的QTL定位则未见到公开报道。本研究利用分析数量遗传学(QTL分析),采用普通小麦京771和pm97034为亲本构建的RIL群体对GMP含量进行积累动态规律分析和QTL定位,旨在为小麦品质育种提供理论依据。主要研究内容和结果如下: 1.用50%正丙醇-1%DTT提取,考马斯亮蓝染色测定GMP含量,结果表明,此法测定快速、结果准确、操作简单、重复性好,蛋白质与吸光值的相关系数为0.97。该改进方法为小麦品质育种提供了一种新的测定方法,能够满足育种早代测定GMP含量的需要。 2.研究结果表明,GMP含量在RIL群体中的分离符合正态分布,GMP含量与谷蛋白膨胀指数(SIG)、湿面筋含量、干面筋含量、Zeleny沉淀值、面筋指数之间呈极显著正相关;GMP与产量性状间相关不显著。 3.在籽粒灌浆至成熟阶段,籽粒GMP含量的动态变化呈现出“低-高-低-高-高”的变化规律。即籽粒灌浆初期GMP的累积量较低,后逐渐升高,但在花后22天左右出现一个明显的低谷期,随后呈逐渐上升趋势,在成熟期GMP积累达到最高。不同发育阶段GMP含量条件遗传分析表明,控制GMP的基因在整个籽粒灌浆时期都有表达,各阶段基因净表达量的变化与GMP观测值的变化基本一致。 4.129个标记SSR位点绘制在包含21条染色体的标记连锁图上。连锁图的总长度是2106.3cM,标记间的平均遗传距离为16.32cM。 5.籽粒灌浆成熟期检测到3个显著加性主效QTL—QGMP1D、QGMP5B、QGMP7B,位于1D、5B、7B染色体上,位点总贡献率为15.86%。检测到8个QTL互作位点,涉及到1A、1D、2A、2B、3B、5A、5B、5D、6D、7B染色体。 6.QTL动态定位研究结果表明,各时期检测到的影响GMP含量的非条件QTL与条件QTL并不完全一致。在所有5个时期,共检测到8个非条件QTL和8个条件QTL,除了QGMP1D-2、QGMP5B位点能在2个不同的测定时期被检测到外,在各个时期能够检测到的QTL都不同,说明这些控制GMP含量的基因都是在某一个特定的时期内表达。条件QTL分析表明,控制GMP的基因在小麦籽粒灌浆过程中的表达具有明显的时空性。在开花后22、27、32天时期内能够检测到2个或者2个以上主效QTL,而花后12、17天时期内只能检测到一个不同的QTL。控制GMP积累的表达基因在开花后17天至22天这一段时期的效应值较小,导致在这一时期测定的GMP含量表型值的下降,形成籽粒GMP积累过程中在该时期的“低谷”。小麦GMP的时空表达规律有利于QTL的分离和克隆。更多还原

【Abstract】 Abstract: Quality improvement is one of important breeding objections for wheat (Triticum aestivum L.). The effect of allelic variation on wheat flour quality is mainly achieved by change the content of GMP, it is significantly positive correlation between the content of GMP and SDS-sedimentation and loaf volume. But the studies about dynamical development and QTL mapping of the content of GMP were seldom. To offer reference for quality breeding of wheat, the study about dynamical development and QTL mapping of the content of GMP in wheat seed was carried out by using the way of analytical quantitative heredity (QTL mapping) and a population of recombinant inbred lines, which derived from a cross between Jing 771 and Pm97034. Major results were distributed below:1. Extracting GMP with 50% 1-propanol that contains 1% DTT, dying protein with Comassie brilliant blue, in this paper, we studied the method of GMP’ extracting, separating and measuring, the results showed: this way was rapid, stable and brief. The coefficient correlation between protein and OD value was 0.97.this way offered a new way of measuring the content of GMP for quanlity breeding of wheat, which can meet the need of early measuring GMP content of seed in wheat.2. The results showed that the distribution of GMP content in recombinant inbred lines population accorded normal distribution, It was significantly positive correlation between GMP content and SIG ,wet gluten content ,dry gluten content ,Zeleny Sed, gluten index, there was no significantly positive correlation between GMP content and related yield traits.3. From grain filling to maturation, The results which studied the dynamical development of GMP content in different period by using RILs indicated: the dynamic change of GMP content in most RILs showed "low-high-low-high-high", which was the same as parents Jing 771 and Pm97034. GMP accumulated at low level in early stage of grain filling, then ascended gradually, but descended about 20 days after fertilization, then ascended continually up to mature date. The results of conditional genetic variance components showed that the expression of GMP quantitative genes was found from filling time to mature time. GMP quantitative gene expression was most active at the stage of 17 days after pollination. However, it was inactive at about 22 days after flowering. The dynamic changes of the GMP net genetic effects were similar to GMP content accumulation.4.129 Simple Sequence Repeat (SSR) makers were assigned on a linkage map which contained 21 chromosomes, the total length of the linkage map equals to 2106.3 cM, with an average interval of 16.3 cM.5. There main-effect additive QTLs about GMP content (QGMP1D、 QGMP5B、 QGMP7B) was detected in stage of grain maturation, which was located on 1D, 5B,7B chromosome, the relative更多还原