HapIII of TaSAP1-A1, a Positively Selected Haplotype in Wheat Breeding

Stress-associated protein (SAP) has functions in maintaining plant cell elongation, embryo development and response to abiotic stresses. TaSAP1-A1, one of the Triticum aestivum SAP1 (TaSAP1) members located on wheat chromosome 7A was isolated for polymorphism analysis. HapIII of TaSAP1-A1 was found significantly associated with thousand-grain weight (TGW) in multiple environments. In this study, HapIII also made a positive contribution to TGW in Population 2. The distribution of TaSAP1-A1 HapIII was tracked among varieties released in different years and geographical environments of China. The frequency of HapIII showed an increasing trend during the breeding process in two different populations. The HapIII was gradually selected and applied from 6.36% in landraces to 13.50% in modern varieties. These results exhibited that TaSAP1-A1 HapIII was positively selected during wheat breeding, which is beneficial for grain-yield improvement. The preferred HapIII was initially selected and applied in the higher latitude areas of China in accord with the long day season and longer grain filling stage in these areas. Moreover, the frequency of HapIII in recent modern varieties was still quite low (19.29–26.67%). It indicated a high application potential of TaSAP1-A1 HapIII for improving grain yield in wheat breeding.     

小麦对缺铁胁迫的适应性反应

采用溶液培养法,比较正常供铁和缺铁胁迫下小麦的生理生化指标,同时设置加氧和不加氧2个处理。结果表明,完全营养液加氧处理的小麦株高和穗长最大,达到51.0cm和7.5cm。缺铁处理降低了小麦的籽粒长、籽粒宽、籽粒厚和穗粒数。正常供铁条件下,小麦植株叶绿素a、叶绿素b和叶绿素总含量显著高于不供铁的小麦。加氧处理的小麦叶绿素含量高于无氧处理的小麦。根际Fe3+还原酶活性在缺铁胁迫条件下达到17.3μmol·g-1·(2h)-1。缺铁处理降低了小麦植株地上部的铁素含量,并且在加氧条件下更明显。Mn、Cu这两种元素和Fe元素之间存在某种拮抗关系。     

Conditional QTL Mapping of Sedimentation Volume on Seven Quality Traits in Common Wheat

To evaluate the possible genetic interrelationships between flour components and the sedimentation volume（SD）,a doubled haploid（DH） population comprising 168 lines were used to identify the conditional quantitative trait loci（QTLs） for SD in three environments.Ten additive QTLs and 15 pairs of epistatic QTLs were detected for SD through unconditional and conditional QTL mapping.Three major additive QTLs were detected for SD conditioned on the seven quality traits.Two additive QTLs were found to be independent of these traits.Three additive QTLs were suppressed by three of the seven traits because of non-detection in unconditional mapping.Three pairs of epistatic QTLs were completely affected by the seven traits because of detection in unconditional mapping but no-detection in conditional mapping.Twelve pairs of epistatic QTLs were detected in conditional mapping.Our results indicated that conditional mapping could contribute to a better understanding of the interdependence of different and closely correlated traits at the QTL molecular level,especially some minor QTLs were found.The conditional mapping approach provides new insights that will make it possible to avoid the disadvantages of different traits by breeding through molecular design.     

不同种植密度对江汉平原三个主推小麦品种产量的影响

以江汉平原主推小麦(Triticum aestivum L.)品种漯麦6010、郑麦9023、鄂麦580为试验材料,设置了每公顷225万、300万、375万3个密度处理,分析了密度对不同品种小麦产量、直链淀粉与支链淀粉含量比值、孕穗及开花期旗叶叶绿素和丙二醛(MDA)含量的影响。结果表明,同一品种不同密度处理间,3个品种在密度为300万/hm~2时,子粒产量和旗叶叶绿素SPAD值均达最高,旗叶MDA含量最低;郑麦9023和鄂麦580在密度为375万/hm~2时直链淀粉与支链淀粉含量比值最高,密度为225万/hm~2时最低,而漯麦6010则在密度为225万/hm~2时比值最高,300万/hm~2时比值最低。同一密度不同品种间,漯麦6010子粒产量和旗叶叶绿素SPAD值最高,鄂麦580最低,郑麦9023居中;而旗叶MDA含量以漯麦6010最低,鄂麦580的最高,郑麦9023居中;鄂麦580的直链淀粉与支链淀粉含量比值最高,其次是漯麦6010,郑麦9023最低。     

花前渍水对长江中下游主推小麦品种产量的影响

为了研究花前渍水对小麦(Triticum aestivum Linn.)产量的影响,对长江中下游主推小麦品种进行花前渍水试验,在拔节期测量SPAD值(叶绿素相对含量),和黄绿叶面积比,孕穗期测量SPAD值和黄绿叶面积比,并对产量及产量构成因素进行分析。结果表明,渍水导致旗叶SPAD值下降,黄绿叶面积比上升,收获指数下降。产量的构成因素中,千粒重、穗粒数、有效分蘖数下降。综合各个品种来看,不同品种的指标参数下降幅度不同,通过分析不同品种指标参数下降幅度,寻找到优势品种襄麦25和皖麦56。     

小麦灌浆过程中旗叶光合及抗氧化代谢与氮素营养关系研究

 【目的】小麦灌浆过程中旗叶光合、抗氧化代谢与氮素营养密切相关,本研究通过田间试验,以进一步揭示其关系。【方法】试验选用多穗中粒（MM）型品种藁城8901（GC8901）和大穗大粒（LL）型品种山农1391（SN1391）,设12 g N•m-2（LN）和24 g N•m-2（HN）2个氮肥处理,在田间条件下研究了小麦灌浆期旗叶光合色素含量、氮素含量、光合特性和抗衰老酶活性对氮素水平的响应。【结果】小麦开花后旗叶氮素含量与叶绿素含量呈下降趋势,净光合速率（Pn）、实际光化学效率（ΦPSⅡ）、开放的光系统Ⅱ反应中心的量子效率（Fv′/Fm′）和光化学猝灭系数（qp）在花后14 d左右开始下降,光系统Ⅱ的最大光化学效率直到衰老末期才有小幅下降,而非光化学猝灭系数（NPQ）呈上升趋势。旗叶光能的吸收和利用之间存在矛盾,这是促其衰老的重要原因。与MM型小麦品种GC8901相比,LL型品种SN1391群体较小,籽粒灌浆后期旗叶的光合色素含量高,光系统Ⅱ的活性下降慢,净光合速率高;同时,抗衰老酶活性下降慢,膜脂过氧化程度轻。氮素水平对2个品种籽粒灌浆过程中旗叶的光合及抗氧化代谢的影响不同。LL型品种SN1391表现为,增施氮肥后旗叶光系统Ⅱ的开放程度和实际光化学效率提高,热耗散降低,净光合速率提高;旗叶的SOD、POD、CAT和APX活性均提高,膜脂过氧化程度降低。增施氮肥后MM型品种GC8901光系统Ⅱ活性下降,用于热耗散的能量增加,光合速率降低;抗氧化酶系活性下降,膜脂过氧化程度加重。【结论】小麦生育后期旗叶光能吸收和利用间的矛盾是促其衰老的重要原因。不同类型小麦品种旗叶生育后期的光合及抗氧化代谢存在显著差异。施用氮肥对小麦旗叶光合、衰老特性的影响因品种类型而不同。     

10个小麦品种对UV-B辐射增强响应的生长和产量差异

在大田条件下,模拟UV-B辐射增强(5.0kJ·m-2,相当于昆明地区臭氧层减少20%),着重研究了10个小麦品种对UV-B辐射响应的生长和产量差异。结果表明,经增强UV-B辐射,10个小麦品种在株高、叶面积指数、分蘖数、地上部分的生物量、产量都发生了明显的变化,且存在种内差异;分蘖数的变化是引起地上生物量(r=0.94,P<0.01)和产量(r=0.92,P<0.01)变化的主要因素;根据生长响应指数(RI)判定供试小麦品种对UV-B辐射增强的耐性顺序为:绵阳26>辽春9>绵阳20>文麦3>文麦5>陇春15>云麦39>凤麦24>会宁18>陇春16。     

普通小麦抽穗期控制基因TaHd1研究进展与展望

抽穗期是对普通小麦(Triticum aestivum L.)安全生产有重要影响的农艺性状,也是一个复杂的受多基因协调互作控制的性状。对普通小麦抽穗期基因控制系统、普通小麦抽穗期基因之一——Ta Hd1的克隆与功能、基因组定位、直向同源区微进化研究进展等方面进行了概述,以期为普通小麦抽穗期性状改良提供一定的理论参考。     

Screening and Analysis of Proteins Interacting with TaPDK from Physiological Male Sterility Induced by CHA in Wheat

To further research the regulatory network of pyruvate dehydrogenase kinase (designated as TaPDK) in physiological male-sterility (PHYMS) of wheat induced by chemical hybridizing agent (CHA) SQ-1, an anther cDNA library was constructed, and the proteins interacting with TaPDK were screened via yeast two-hybrid technique. Subsequently, a few candidate proteins in nucleotide expression levels were detected by real-time quantitative PCR. Yeast-two hybrid screening was performed by mating yeast strain Y2HGold containing BD-TaPDK bait plasmid with yeast strain Y187 including anther cDNA library plasmid. Diploid yeast cells were plated on synthetic dropout nutrient medium (SD/-Ade/-His/-Leu/-Trp) (QDO), and further were incubated on QDO medium containing AbA and X-α-Gal. The interactions between TaPDK and the proteins obtained from positive colonies were further confirmed by co-transformation validation. After plasmids DNA were extracted from blue colonies and sequenced, the sequences results were analyzed by bioinformatic methods. Finally, 24 colonies were obtained, including eight genes, namely non-specific lipid-transfer protein precursor (TanLTP), polyubiquitin (TaPUbi), glyceraldehyde-3-phosphate dehydrogenase, proliferating cell nuclear antigen (TaPCNA), CBS domain containing protein (TaCBS), actin, guanine nucleotide-binding protein beta subunit, chalcone synthase, and three new genes with unknown function. The results of quantitative RT-PCR showed that the expression levels of TanLTP, TaPUbi, and TaPCNA were obviously up-regulated in PHYMS anther, and TaCBS expression was only increased at the tricellular stage in PHYMS anther compared with in fertile lines. Whereas, the expression of TaPDK was obviously down-regulated in PHYMS lines. Collectively, these datas indicated that the majority of candidate proteins might be related to pollen abortion in PHYMS lines, which further suggested that TaPDK plays multiple roles in pollen development, besides participating in regulating pyruvate dehydrogenase complex activity.     

小麦、大麦耐渍性种质改良的研究综述

对小麦、大麦耐渍性种质改良前景进行了综述.土壤渍水的时间和空间变化,以及影响植株生长发育的其他环境因子决定了作物存在不同的耐渍机制.小麦、大麦均具有一定的耐渍遗传多样性和较高的耐渍遗传力,其耐渍机制可分为物候学、形态学和解剖学、营养学、代谢学以及缺氧的后期破坏和恢复等5种,通过提高选择标准、利用广泛杂交和转基因技术增强耐溃遗传多样性是种质改良的有效手段.     

小麦新品种漯麦6010稳产性、产量构成因素变异性及通径分析

以2010-2013年湖北省小麦(Triticum aestivum L.)区域试验结果为依据,利用产量变异系数和高稳系数法对漯麦6010稳产性和产量构成因素进行相关性分析,并对产量构成因素进行通径分析。结果表明,产量结构三要素中,以穗粒数和千粒重最为稳定,其变异系数较小;穗数与产量的相关性最大,千粒重次之,穗粒数与产量呈负相关;穗数与穗粒数呈正相关,千粒重与穗数、穗粒数均呈负相关;通径分析结果表明,穗数、千粒重、穗粒数与产量的相关系数分别为0.305 3、0.268 2、-0.103 2,且直接通径穗粒数最大,千粒重次之。     

鲁麦21和济南17胚乳发育过程中淀粉粒的动态变化

 【目的】以2个不同品质类型的小麦品种为供试材料,分析小麦胚乳中淀粉粒的分布特征和变化特点。【方法】选用鲁麦21（弱筋）和济南17（强筋）两个小麦品种,利用激光衍射粒度分析仪研究其胚乳发育过程中淀粉粒的积累动态。【结果】花后不同时期小麦胚乳淀粉粒数目的变化均呈单峰曲线,峰值出现在0.5～1.1μm。花后7 d,A-型淀粉粒已经出现,最大直径20μm;花后10 d,淀粉粒直径范围扩大到30μm;至花后14 d, B-型淀粉粒开始产生;花后21 d又产生了一个新淀粉粒群体,即C-型淀粉粒;花后24～28 d,籽粒中新淀粉粒的产生仍在继续;花后35 d,主要是最小粒径淀粉粒直径的扩大。与强筋小麦济南17相比较,花后7～14 d,弱筋品种鲁麦21胚乳中小于0.6μm的淀粉粒数目百分比较低,大于0.6μm的淀粉粒数目百分比较高,花后17～28 d则相反。【结论】灌浆前期鲁麦21胚乳中淀粉粒的增长速率较快,而灌浆后期新淀粉粒合成能力较强。成熟期,济南17籽粒中的B-型淀粉粒所占体积和表面积百分比较高,而弱筋小麦鲁麦21的A-型淀粉粒体积和表面积百分比较高。     

小麦颖果韧皮部细胞ATPase活性及其与籽粒光合同化物积累关系

 【目的】探明韧皮部细胞ATPase分布规律,分析韧皮部细胞ATPase活性与籽粒光合同化物量之间的关系。【方法】在小麦（Triticum aestivum L.）灌浆不同阶段,采用蒽酮法测定籽粒光合同化物积累量;运用显微细胞化学技术对颖果韧皮部和胚乳细胞的多糖进行定位,同时对韧皮部细胞ATPase进行超微细胞化学定位。对籽粒光合同化物积累量与韧皮部细胞ATPase活性产物量进行相关分析和线性回归分析。【结果】(1)在灌浆渐增期,籽粒积累的光合同化物主要是可溶性糖。约在花后14 d,籽粒可溶性糖和淀粉积累量含量相等。以后,籽粒以积累淀粉为主。在整个灌浆期,籽粒可溶性糖和淀粉量的变化呈现彼此消长,但籽粒总糖含量一直呈“S”型增长。在灌浆渐增期和快增期,韧皮部筛分子（Sieve element,SE）的细胞壁和胚乳细胞的淀粉粒均被锡夫试剂染成鲜红色;但在灌浆缓增期,上述细胞染色明显变浅。（2）在SE、中间细胞（Intermediary Cell,IC）、伴胞（Companion Cell,CC）和韧皮薄壁细胞（Phloem Parenchyma Cell,PPC）中,ATPase活性产物主要分布于质膜、细胞内壁和靠近质膜的囊泡上。在SE内的P型-质体和线粒体的双层膜上、SE和IC之间分枝状的胞间连丝上也有较强ATPase活性。在灌浆渐增期和快增期,SE的ATPase活性高,而在缓增期,IC的ATPase活性较SE高。（3）SE中ATPase酶活性产物与籽粒可溶糖呈显著负相关;与籽粒淀粉含量呈极显著正相关;与籽粒总糖呈显著正相关,且ATPase活性产物与光合同化物积累量之间有明显的线性关系。IC中ATPase活性产物只与籽粒可溶糖呈极显著正相关。【结论】在灌浆过程中,籽粒中可溶性糖和淀粉量的增加彼此消长,但总糖含量一直增加。籽粒光合同化物积累量与SE和IC中ATPase活性产物量之间有显著或极显著的相关关系。韧皮部细胞ATPase活性产物呈现出动态的时空变化。SE在灌浆前2个阶段起主要的同化物运输作用,而IC主要在灌浆第3阶段起主导作用。上述结果为小麦籽粒灌浆生理研究提供了细胞学基础。     

基于AquaCrop模型的小地区气候变化对小麦产量的影响

为了研究甘肃省高台县气候变化对小麦(Triticum aestivum L.)产量的影响,对该地区50 a的气象因素变化进行了分析,并且利用Aqua Crop作物模型模拟不同年份小麦的生产潜力。结果表明,年平均气温、年平均最高气温、年平均最低温度均呈增长趋势,增长幅度为0.021 5、0.012 4、0.014 5℃/a,总降雨量也呈增长趋势,增长幅度为0.220 2 mm/a,而日照时间呈降低趋势,降低幅度为1.328 8 h/a,并拟合得到了相应的线性趋势公式。该地区小麦生产潜力较低,平均模拟产量为5 807.5 kg/hm~2,不同年份间小麦产量差异极显著,并且从气候变化因素分析了该地区小麦产量变化的原因。     

Cloning and Characterization of a Putative CTR1 Gene from Wheat

CTR1 is a key negative regulator in ethylene signal transduction. A salt-induced CTR1 like gene （TaCTR1） was cloned from wheat, its expression under abiotic stresses, subcellular localization and the effect of overexpression of TaCTR1 on salt tolerance in tobacco was studied. A putative CTR1 gene was cloned and characterized from wheat via rapid amplification of cDNA ends （RACE） and RT-PCR. TaCTR1 expression under stresses was analyzed using semi-quantitative RT-PCR and the effect of overexpression of TaCTR1 on salt tolerance was conducted in tobacco. The full-length cDNA of TaCTR1 is 2 635 bp which codes for a polypeptide of 759 amino acids. There is a conserved serine/threonine protein kinase domain at the carboxyl terminus containing an ATP-binding site. Southern blot analysis revealed that TaCTR1 consisted of a gene family in wheat. The amino acid homologies of CTR1 among different organisms share higher similarities. Expression analysis revealed that TaCTR1 was induced by NaC1 and drought stress but inhibited by ABA treatment. Transient expression of TaCTR1-GFP in the onion epidermal cells indicated that TaCTR1 was probably targeted to the plasma membrane. Overexpression of TaCTR1 decreased salt tolerance in transgenic tobacco （Nicotiana tabacum L.） plants compared with the control. To our knowledge, TaCTR1 is the first CTR1 gene cloned in wheat and may be involved in various abiotic stresses. Overexpression of TaCTR1 decreased the salt tolerance in tobacco suggested that TaCTR1 may act as a negative regulator of salt stress in plants.     

喷洒有效微生物群（EM）对小麦旗叶衰老和籽粒产量的影响

小麦植株喷洒有效微生物群制剂（ＥＭ），显著提高了旗叶衰老期间的光合作用速率和叶片可溶性蛋白质及叶绿素含量，降低了叶片细胞膜脂过氧化作用，提高了籽粒生长速率并显著增加了籽粒产量。     

小麦新品种农艺性状与产量的相关及通径分析

利用2006～2007年度区域试验湖北武昌点的34个小麦新品种(系),对其产量及其相关的10个农艺性状进行了相关和通径分析.结果表明,参试小麦新品种(系)各性状值方差分析均达到极显著水平:产量与旗叶面积、旗叶长、穗粒数和旗叶宽相关极显著,其他各农艺性状间也存在着许多极显著相关性:通径分析表明,穗粒重、穗粒数和千粒重对产量的直接贡献最大.但三者在相互制约的同时.也是其他性状影响产量的主要因素.相关和通径分析一致表明,穗粒数是当前影响小麦高产育种的主要因素,通过适当增大旗叶性状来减少不孕小穗和小花数可增加穗粒数,是提高小麦产量水平的主要途径.