普通野生稻矮化突变体的株高与分蘖基因的QTL 定位及主效基因的遗传分析

为了挖掘和克隆更多控制株高与分蘖的基因应用于水稻育种,利用多分蘖普通野生稻矮秆突变体与少分蘖高秆南特号组配杂交组合F1并构建分离群体F2;并且对该群体的株高与有效分蘖数进行性状遗传分析以及基因型检测,利用IciMapping V3．0对株高与分蘖数进行QTL连锁遗传分析。结果表明,两亲本的株高与分蘖数均为多基因控制的数量性状,且存在极显著的正相关;利用平均分布于水稻12条染色体上的345对分子标记对两亲本普通野生稻矮秆突变体与南特号进行多态性筛选,共筛出194对差异明显的多态标记,多态率为56．23％;利用122对基因型清晰的多态标记对571株F2分离群体进行连锁分析,共获得33个与株高相关的QTLs,19个与分蘖数相关的QTLs;检测到1个与株高有关的主效QTLs,定位于1号染色体RM302～RM104标记之间,对表型贡献率达71．72％。找到一个控制株高的主效QTL,与分子标记RM302和RM104紧密连锁,对株高具有极强的矮化效果,该结果为进一步克隆矮秆基因与株型分子育种提供理论基础。     

水稻少分蘖高秆突变体的遗传分析和基因定位

研究水稻少分蘖高秆突变体的分子机理,鉴定出新的水稻少分蘖高秆基因。本研究利用γ射线辐射诱变籼稻品种泸恢H103,获得一个少分蘖高秆突变体,命名为ltn1(low-tiller number)。研究了该突变的主要农艺性状与遗传方式,并对突变体基因LTN1进行了分子定位。结果显示突变体的株高,有效穗,结实率,千粒重,单株产量均与野生型存在显著差异。遗传分析表明突变体ltn1受一对隐性基因控制,将突变体和沈农265的F2代中的突变型个体作为定位群体,利用SSR和Indel分子标记将突变体定位在水稻第8染色体标记RM3840和RM23611之间,物理距离为135 kb的区间。在这个区间内有个预测注释基因LOC_Os08g44510。     

调控高粱分蘖高度的基因及表达分析

分蘖高于主茎是困扰高粱品种整齐度和机械化生产的重要原因之一,为了阐明高粱调控分蘖高度基因的作用机制,提高高粱品种整齐度、选育适宜机械化生产高粱品种,依据前期的定位结果,利用15份分蘖与主茎整齐一致和17份分蘖高于主茎的高粱品种组成自然群体对候选基因进行验证,发现SNP3位点影响分蘖高度,所属基因为Sobic.009G213300.1.v3.2,命名为SbTH,位于水解酶＿4保守区域。以分蘖高度与主茎一致的K35-Y5和分蘖高于主茎的1383为材料,通过实时荧光定量PCR分析SbTH基因在高粱不同组织中的表达模式。结果表明,2个材料SbTH基因在根和叶中均有表达,虽然表达量有差异,但趋势基本一致;1383主茎和分蘖茎基因表达量和趋势也基本一致,而K35-Y5在主茎开花期时呈反向表达,主茎表达量达到最高,同期的分蘖茎表达量降到最低。分析认为,SbTH在K35-Y5分蘖中表达量低,控制了分蘖节间的过度生长,形成主茎与分蘖高度一致的株型,而在1383分蘖中表达量高,促进分蘖节间的生长,使得分蘖比主茎高,SbTH基因在主茎开花期的差异表达是影响分蘖株高的关键。     

控制水稻穗伸出度和株高的数量性状基因定位

水稻穗伸出度和株高是影响杂交水稻制种产量的重要农艺性状。本研究利用越光/Kasalath//越光杂交回交产生的重组自交系群体（backcross recombinant inbred lines,BILs）对穗伸出度与其相关株高数量性状基因位点（QTL）进行检测和遗传效应分析。结果表明,对穗伸出度的检测中,共检测到4个QTL（qPE-1,qPE-2,qPE-3-1和qPE-3-2）,分别位于水稻的第1,2,3（2个QTL）染色体上,其贡献率为6.62%～17.16%,其中位于第3染色体上的qPE-3-2的贡献率为最大（17.16%）,来自越光的等位基因能增长穗伸出度1.61cm;对株高性状的检测中,检测到QTL共有3个（qPH-1,qPH-6和qPH-12）,分别位于第1、6和12染色体上,分别能解释28.53%,15.30%和5.01%的株高变异。有趣的是除了qPE-1位点,其他3个与穗伸出度相关的QTLs将不会影响水稻株高的生长。本研究中检测到QTLs的两侧的连锁分子标记可用于分子育种培育穗伸出度和株高兼顾型的水稻品种。     

巨穗小麦种质株高的基因定位

巨穗小麦新种质材料是一具有茎杆粗壮、叶片短宽直立、大穗、大粒、高结实率等特点的种质资源。本研究应用单体分析和双端体分析方法对241材料进行了遗传学研究。结果表明，小麦新种质材料241的1A，3A，5A和4R染色体上具有控制株高的隐性基因，6B染色体上具有控制株高的显性基因，其中3A，5A和6B染色体上的基因表现为强效，1A和4B染色体上的基因表现为弱效。通过双端体分析进一步将控制株高的基因定位到1AS，3AS，5AL和4BL上。     

巨穗小麦种质株高的基因定位

巨穗小麦新种质材料是一具有茎杆粗壮、叶片短宽直立、大穗、大粒、高结实率等特点的种质资源。本研究应用单体分析和双端体分析方法对“241”材料进行了遗传学研究。结果表明,小麦新种质材料“241”的1A、3A、5A和4B染色体上具有控制株高的隐性基因,6B染色体上具有控制株高的显性基因,其中3A、5A和6B染色体上的基因表现为强效,1A和4B染色体上的基因表现为弱效。通过双端体分析进一步将控制株高的基因定位到1AS、3AS、5AL和4BL上。     

饲用高粱分蘖及其他性状的QTL定位研究现状与进展

饲用高粱作为酿酒和牲畜饲料的重要原料,拥有众多优良的农艺性状,其全基因组测序工作已经完成,分子标记辅助选择技术广泛应用于高粱育种工作中,影响高粱农艺性状的数量基因位点已被定位得到.分蘖作为一项重要的株型性状,对高粱的耐密性、抗倒性、光吸收效能等生理特性有重要的影响.当前饲用高粱株高、穗长、叶部形态等性状的基因定位工作已...     

小麦主茎优势或分蘖优势与肥水运筹关系的初步分析

本文通过对单株成穗数与穗粒数等关系不同的试验结果进行分析后看出，肥水运筹对小麦主茎优势或分蘖优势有重要影响。认为，起身或起身前肥水有助于分蘖优势的发挥，拔节或拔节后肥水有利于主茎优势的发挥，从一个新的角度为不同高产途径各配套技术体系的肥水运筹，提供了科学依据。     

福建野生薏苡与栽培薏苡株高与分蘖的观察比较研究

试验研究比较了5种农家栽培薏苡与5种野生薏苡在株高、日生长速度和分蘖动态上的异同。日生长速度与株高测定结果表明,农家薏苡中,龙薏1号与临2无显著差异,但与其余3个品种有显著差异;野生薏苡品种间,日生长速度没有显著差异;品种间的株高存在极显著差异,河2株高最高,与河1、石陂没有显著差异,但与寿宁有显著差异,与临1有极显著差异;野生薏苡株高伸长的延续时间上较栽培薏苡长15 d。农家品种表现出2个明显的分蘖缓慢期,分别在5月底(5月30日,约44 d)与6月初(6月5日,约50 d),野生品种没有明显分蘖放缓现象,直到营养生长后期才放缓分蘖。采用一元非线性Logistic回归模型拟合了株高与分蘖的方程,决定系数都在0.92以上。     

玉米株高QTL定位研究进展

株高作为玉米的重要农艺性状,对产量、耐肥性、抗倒伏影响显著。随着分子生物学的发展,针对玉米株高性状开展了大量研究工作。总结玉米株高相关的QTL定位和基因克隆研究进展,并采用元分析技术对187个信息完整的玉米株高QTL定位结果进行整合分析,获得10个一致性QTL,并在一致性QTL置信区间内发掘可能参与玉米株高调控的候选基因。     

A single recessive gene for stem sweetness in sorghum

Summary The inheritance of stemsweetness in sorghum has followed a qualitative pattern, non-sweet being monogenically dominant over sweet. Hence sweetness was controlled by a single recessive gene. A maternal effect was not involved for the expression of sweetness.     

Spike formation and seed setting of the main stem and tillers under post-jointing drought in winter wheat

To clarify the influence of post-jointing drought on the ear-bearing and seed-setting characteristics of the main stem and tillers of winter wheat (Triticum aestivum L.), a pot experiment was conducted with cultivars “Shannong 29” (SN29) and “Heng 0628” (H0628), and five water regimes: mild drought (WR1) and severe drought (WR2) for 0–5 days after jointing, mild drought (WR3) and severe drought (WR4) for 0–10 days after jointing and adequate water supply as a control (CK). The present study focused on primary tillers (appear in the axils of main stem leaves: T1, T2, T3, T4, etc.), as well as on secondary tillers (appear from the bud in the axil of the prophyll: T10 and T20; appear in the axil of the first leaf of the primary tiller T1: T11). The yield components of tillers showed a downward trend with increasing tiller position and drought degree and duration, and the kernels per spike, single kernels weight and grain yield per spike of tillers T2, T3, T10 and T4 decreased more than those of the other tillers. These outcomes may be related to the spike developmental stages at the time of the drought period. Severe drought during the period from when the stamen primordium is first present (Waddington’s stage 4) to when the carpel extends around the three sides of the ovule (Waddington’s stage 5) significantly decreased the seed set of tillers, but short-term (5 days) mild drought during this period and even a short-term severe drought before Waddington’s stage 4 had little effect on the seed set of tillers. The ear-bearing capacity of tillers was determined not only by the spike developmental stage, but also by the gap from the main stem and the competition of nutrition and space between tillers. Although the ear-bearing rate of tillers T3 and T10 decreased rapidly after the short-term mild drought, the increase in the ear-bearing rate of tillers T20 and T11 effectively compensated for the loss of the number of spikes per plant. Therefore, the short-term mild drought at the jointing stage had no significant effect on the grain yield of the two cultivars. The tillers T2, T3, T10 and T4 were sensitive to soil moisture in the jointing stage and had high plasticity. During this period, if timely irrigation improves soil moisture, it is expected to increase the ear-bearing rate and seed set of these tillers, thereby increasing grain yield.     

甘蓝型油菜茎高QTL定位及株高相关位点整合

甘蓝型油菜主茎高度(茎高)是株型的构成因子之一,研究其遗传机理对油菜株型改良具有重要的理论指导意义。目前对甘蓝型油菜茎高研究的报道较少。本研究以2个油菜茎高差异较大的亲本构建的重组自交系群体为材料,利用SNP高密度遗传图谱, 2年共检测到11个茎高QTL,分布在A04、A06、C04、A08和C01染色体上,位点的表型贡献率为7.25%～19.61%。同时,以455份来源不同的甘蓝型油菜为材料,结合重测序产生的SNP标记,对茎高进行全基因组关联分析, 2年共检测到5个SNP与茎高性状显著关联,分布在A08、A10、C02和C06染色体上。根据茎高定位结果,找到一些与激素途径(生长素、赤霉素和油菜素内酯)、光形态建成及植物生长发育相关的候选基因。在此基础上,结合国内外株高相关性状定位研究结果,将株高相关性状位点整合到甘蓝型油菜参考基因组上,发现4个以上群体都在A01、A03、A07、C03和C06染色体上找到株高定位的区间,2个群体在A10染色体上找到主花序长度共同定位的区间,在A02和C03染色体上找到一次分枝高度共同定位的区间。本研究中的茎高定位结果与整合后的株高相关性状QTL定位区间有部分重叠,位于A04、A06、A08、C04和C06染色体上。上述结果为甘蓝型油菜理想株型育种提供了理论依据。     

大豆主茎节数数量性状座定位及遗传效应分析

为了定位控制主茎节数的QTL并明确其遗传效应,利用100对SSR引物,并采用Mapmaker Exp 3.0和复合区间法,研究构建了一张包括3个连锁群的连锁图谱。以‘黑农37’（栽培大豆）×ZYD581（野生大豆）组合的亲本、F₂、F₃为试材,分别在chr1连锁群上定位了一个影响大豆主茎节数的QTL,2007年QTL位于Satt238—Satt242这个区间内,与Satt238的遗传距离是0.01 cM,与Satt242的遗传距离是24.69 cM,其遗传贡献率为17.22%,加性效应为-3.2608;2008年QTL位于Satt238—Satt240之间,与Satt238的遗传距离为0.59 cM,与Satt240的遗传距离为6.01 cM,其遗传贡献率为6.68%,加性效应为-1.4965。2年大豆主茎节数QTL分析表明,在chr1连锁群上Satt238附近确定了1个控制大豆主茎节数QTL位点。     

Mapping of QTLs underlying flowering time in sorghum [Sorghum bicolor (L.) Moench]

Due to its critical importance in crop yield, the photoperiodic regulation of flowering time is considered an important trait in sorghum breeding programs. In this study, quantitative trait loci for flowering time were detected using an F₂ population derived from a cross between Kikuchi Zairai, a late-flowering cultivar originating from Japan and SC112, an early-flowering cultivar originating from Ethiopia. F₂ plants were grown with their parents under a natural day length and a 12 h day length. Two linkage maps were constructed using 213 simple sequence repeats markers. Nine quantitative trait loci controlling flowering time were identified in F₂ plants grown under a natural day length, whereas 7 QTLs were identified under a 12 h day length. Five QTLs controlling flowering time were shared under both of the day length conditions.     

Chromosomal locations and genetic relationships of tiller and spike characters in wheat

Number of tillers per plant, plant growth habit in seedling and adult stages, and spike and spikelet characters are agronomically important features of the gross morphology of wheat. To localize to wheat chromosomes the genes for these traits, we scored them in a set of wheat recombinant-inbred mapping lines already well genotyped with molecular markers. Quantitative-trait analysis revealed a region near Gli-A2 (Xpsr10) on the short arm of chromosome 6A strongly affecting tiller number and the correlated trait of seedling growth habit. Genes with opposing effects on adult plant type were localized on the short arms of chromosomes2A and 3A, while genes affecting spike development were assigned to several A- and B-genome chromosomes. None of these genes showed synteny with counterpart QTLs reported to affect the same traits in rice. In the chromosome 2D region containing the photoperiod-insensitivity gene Ppd-D1, the major determinant of heading date in these autumn-sown lines, earliness alleles reduced tiller and spikelet numbers and increased erect seedling growth habit, but showed no influence on adult plant type or spike length. Though several of these morphological traits are generally considered to be associated with winter hardiness and their phenotypic intercorrelations were consistent with the genetic mapping evidence, no association was found between newly identified loci and known vernalization-response or frost-resistance loci. This revised version was published online in August 2006 with corrections to the Cover Date.     

增强叶片氮素输出对水稻分蘖和碳代谢的影响

增施氮肥是保证水稻高产的重要栽培措施,但高氮肥投入所增加的植株氮素积累大部分滞留在营养器官中,对产量的促进作用有限。叶片是氮素储存的主要器官及籽粒氮素的主要供给源。为了明确植株中氮素分配对水稻生长的影响,本研究将拟南芥铵转运蛋白基因AtAMT1.2在水稻韧皮部特异表达,促进叶片氮素输出,检测转基因水稻植株在不同氮肥浓度下的生长情况。试验结果显示,高氮下pOsSUT1::AtAMT1.2转基因水稻分蘖数、氮素利用效率显著增加,叶片中糖输出量增加,分蘖芽中独角金内酯途径相关基因OsTB1、OsD14表达水平下调。研究说明增加叶片氮素输出能够增大叶片中糖向分蘖芽的转运量,促进分蘖生长,从而提高了有效分蘖数并带来了更高的氮素利用效率。     

Inheritance of resistance to the panicle-feeding bug Eurystylus oldi and the sorghum midge Stenodiplosis sorghicola in sorghum

A study of the inheritance of sorghum resistance to head-bug Eurystylusoldi and midge Stenodiplosis sorghicola has been conducted from anF1-based complete diallel involving four parental lines (namely head-bugresistant Malisor 84-7 & 87W810, and susceptible S 34 & ICSV 197).The trial was conducted at Samanko, Mali, under both natural and artificialhead-bug infestation, in one date of sowing (DOS) in 1995 and two DOSin 1996. Head-bug visual damage scores (under both types of infestation)were indicated and analyzed in all these trials. Head-bug numbers underartificial infestation on the two DOS of 1996, and midge damage scoreunder natural infestation on the second DOS of 1996 were recorded. Allfour parents confirmed their expected level of resistance to head-bugs,while ICSV 197 confirmed its resistance to midge. Diallel analyses showedthat general combining ability (GCA) and thus additive gene effects werevery important in the inheritance of resistance to both pests. Specificcombining ability and maternal effects were generally of minor importance.Mean performance of the parents and their GCA effects were linked, whichsuggests high heritability. Head-bug resistant parents, Malisor 84-7 &87W810, with high per se resistance and negative GCA shouldtherefore be used in breeding for resistance to this pest, while for a similarreason, ICSV 197 should be used in breeding for midge resistance. Resultsconcerning independance between resistance to head-bugs and to midge,are also discussed.     

基于QTL定位和全基因组关联分析筛选甘蓝型油菜株高和一次有效分枝高度的候选基因

株高和一次有效分枝高度是与甘蓝型油菜结荚层厚度、收获指数紧密关联的重要农艺性状,有关株高的数量性状位点(quantitativetraitlocus,QTL)和全基因组关联分析(genome-wideassociationstudy,GWAS)已有很多报道,但对一次有效分枝高度的QTL和GWAS定位以及候选基因筛选的研究报道较少。本研究利用已构建的高密度遗传连锁图对2016和2017年2个环境的186个株系组成的重组自交系群体株高和一次有效分枝高度及其最佳线性无偏预测(bestlinearunbiasedprediction,BLUP)值进行QTL定位共检测到8个株高的QTL,分别位于A03、A04和A09染色体,单个QTL解释4.60%～13.29%的表型变异,其中位于A04染色体上的QTL(q-2017PH-A04-2和q-BLUP-PH-A04-2)在2017年和BLUP中均被检测到;检测到9个一次有效分枝高度QTL,分别位于A01、A02、A05、A09、C01和C05染色体上,单个QTL解释5.12%～19.10%的表型变异,其中q-2017BH-A09-1、q-BLUP-B...