Chemical composition and pasting properties of einkorn (Triticum monococcum L. subsp. monococcum) whole meal flour

Einkorn (Triticum monococcum L. subsp. monococcum) is an ancient wheat appreciated for its high proteins, carotenoids and tocols content. To better understand its potential for human consumption and food preparation, composition and pasting properties of 65 einkorn accessions, of different geographical origin but cultivated at S. Angelo Lodigiano (Italy), were evaluated. Eight Triticum turgidum and seven Triticum aestivum cultivars, belonging to different subspecies, were assessed as controls.On average, the einkorn samples had light seeds (25.0 mg/kernel), extra-soft texture (238.3 g), high protein content (18.2%), high ash content (2.35%), low SDS sedimentation volume (25.6 ml), high carotenoids (8.36 μg/g) and high yellow pigments (8.46 μg/g). The pasting parameters studied were peak viscosity (average: 2426 cP), breakdown (765 cP), final viscosity (2788 cP) and setback (1126 cP). Total amylose (25.7%) and total starch (65.5%) were also measured. Significant differences from the controls and a broad variation for all the traits analysed were observed. Einkorns from diverse geographical areas showed different mean values for all characters, apart from ash content.The good pasting properties, coupled with high proteins and carotenoids content, suggest that einkorn is particularly suited for the production of baby and specialty foods.     

Radical scavenging activity of einkorn (Triticum monococcum L. subsp. monococcum) wholemeal flour and its relationship to soluble phenolic and lipophilic antioxidant content

The present research assessed the radical scavenging activity against the synthetic 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radical of the water-saturated 1-butanol extracts of wholemeal flour from 63 Triticum monococcum accessions, which originated from different eco-geographical areas. On average, T. monococcum had higher radical scavenging activity than T. turgidum and T. aestivum species, which served as controls (0.90, 0.64 and 0.70 mmol TE/kg DM, for T. monococcum, T. turgidum and T. aestivum, respectively). A significant correlation between radical scavenging activity and tocol content was observed, while no correlation existed with soluble phenolics and carotenoid contents.     

Storage-induced changes in einkorn (Triticum monococcum L.) and breadwheat (Triticum aestivum L. ssp. aestivum) flours

To assess the effect of ageing on alpha-amylase activity, falling number, pasting properties and SDS sedimentation volume, whole meal and white flours of einkorn (cv Monlis) and bread wheat (cv Serio) were stored in darkness at different temperatures and analysed several times up to 374 days. Pregerminated bread wheat flours (cv Blasco) were also evaluated.     

Impact of genetic and environmental factors on einkorn wheat (Triticum monococcum L. subsp. monococcum) polysaccharides

To evaluate the effect of genotype, year and location on 1000 kernel weight, falling number, alpha- and beta-amylase activity, pasting properties, β-glucan, fructan, total starch, amylose, resistant starch and dietary fibre contents of wholemeal flour, four einkorns and one control bread wheat were cropped in Italy for two years in four different locations.     

TDZ在小麦花药培养中的作用

为了进一步提高小麦花药培养效率,以8个小麦杂交F1代为供试材料,通过在培养基中添加不同浓度的噻重氮苯基脲(thidiazuron,TDZ)探讨其对小麦花药培养的作用。结果表明,TDZ的作用与添加剂量及小麦基因型密切相关。在诱导培养基中添加TDZ对基因型中麦875/郑豫麦043具有负向调控作用,但对兰考198/黄明118、郑麦7698/西农979以及天禾7号/0836H-3则具有正向促进作用。TDZ的最佳添加剂量为0.05mg·L-1,可显著提高3个基因型的胚性愈伤组织诱导率和绿苗产率,其中兰考198/黄明118胚性愈伤组织诱导率和绿苗产率最高,分别达到25.1%和8.7%。同样,在分化培养基中添加一定剂量的TDZ,对4个基因型的愈伤组织分化均表现正向促进作用,TDZ的适宜浓度范围为0.5~1.0mg·L-1,以添加0.5mg·L-1的处理表现最优,能够显著提高绿苗分化率和绿苗/白苗比率;基因型兰考198/黄明118的绿苗分化率和绿苗/白苗比率最高,分别达50%和1.87。研究还表明,在诱导培养基或分化培养基中添加TDZ还能够促进绿苗增殖,提高单倍体自然加倍效率。本研究结果将有助于小麦花药培养技术的优化,进而提高花培育种效率。     

Tolerance of spring barley (Hordeum vulgare L.), oats (Avena sativa L.) and wheat (Triticum aestivum L.) to saflufenacil

Saflufenacil is a new herbicide being developed by BASF for pre-emergence application for broadleaved weed control in maize and other crops. Three field studies were conducted in Ontario, Canada over a 2-year period (2006 and 2007) to evaluate the tolerance of spring cereals (barley, oats, and wheat) to pre-emergence and post-emergence applications of saflufenacil at 50 and 100 g ai ha⁻¹. Saflufenacil pre-emergence caused minimal visible injury (1% or less) at 3, 7, 14 and 28 days after emergence and had no adverse effect on plant height or yield of barley, oats, and wheat. Saflufenacil plus the surfactant Merge (1% v/v) applied post-emergence caused as much as 76, 60, 52 and 35% visible injury in spring cereals at 3, 7, 14 and 28 DAT, respectively. Injury with saflufenacil plus Merge applied post-emergence decreased over time and was generally greater as dose increased. Saflufenacil plus Merge applied post-emergence reduced plant height by as much as 16% and reduced yield of spring barley and wheat by 24 and 13%, respectively, but had no effect on the yield of spring oats. Based on these results, saflufenacil applied pre-emergence at the proposed dose can be safely used in spring planted barley, oats and wheat; however, the post-emergence application of saflufenacil results in unacceptable injury and yield loss. These results are consistent with the proposed pre-emergence use pattern for saflufenacil.     

Effect of wheat (Triticum aestivum) cultivars and seeding rate on yield loss from Galium aparine (cleavers)

Galium aparine L. is a troublesome broadleaved weed in winter wheat fields and other winter-sown crops in Eurasia and North America. Field experiments were conducted in Havza and Kavak, Samsun-Turkey, to evaluate the effect of different densities of G. aparine on the productivity of four wheat cultivars and to determine the effects of different seeding rates of wheat cultivars on the competitive ability of G. aparine. In experiments over 3 years, the wheat cultivar Panda was taller at maturity than other cultivars at both sites. Although Bezostaja was naturally shorter than other cultivars, its height decreased less due to competition from G. aparine than other cultivars. Wheat grain yields increased with seeding rate, either in the presence or in the absence of G. aparine at both locations. Based on wheat yields the relative competitiveness of the wheat cultivars was Bezostaja>Momtchill=Panda>Kate A-l. G. aparine biomass and seed numbers were reduced by an increase in the wheat seeding rate and by cultivar effects.     

小麦ArfGAP基因的克隆、半定量RT-PCR分析及原核表达

为明确小麦ArfGAP基因在非生物胁迫中所行使的功能,采用电子克隆技术分离普通小麦ArfGAP基因后对其在不同非生物胁迫下的表达特性进行了分析,并在大肠杆菌中表达了该基因。结果表明,从扬麦18号中克隆得到的TaArfGAP基因ORF全长为2 121bp。生物信息学分析表明,TaArfGAP蛋白氨基端方向存在一个典型的ArfGAP蛋白结构域,在亲缘关系上与山羊草、乌拉尔图小麦和短柄草较近,而与甘蓝等作物关系较远。半定量RT-PCR分析表明,TaArfGAP基因在干旱、PEG和NaCl胁迫下显著上调表达,但在高温条件下则显著下调表达。SDS-PAGE检测结果表明,IPTG终浓度为0.8~1.0mmol·L-1、诱导温度为24℃及诱导时间为10h时,在分子量大小为81kD左右可以得到较大的可溶性表达蛋白量,且与预期结果一致,说明TaArfGAP基因在原核表达体系中成功表达。     

普通小麦几丁质酶基因的克隆与表达分析

几丁质酶是植物重要的防卫因子之一,与植物抗病性密切相关。为深入了解几丁质酶基因表达及功能,先利用引物ChiF/ChiR从10份具有不同抗病性的小麦中克隆出几丁质酶基因后对其进行序列分析及原核表达分析,再利用荧光定量PCR(qRT-PCR)技术分析小麦根、茎和叶不同组织中几丁质酶基因的表达情况,并选取在小麦根、茎和叶中表达量最高的几丁质酶基因进行真菌性病害的抗性反应试验。结果表明,从10份具有不同抗病性的小麦中克隆得到5条长度约960bp的几丁质酶基因序列,其中1条序列与已公布的Chi-3基因序列(序列登录号为KJ507387)一致,其余序列命名为Cht1~Cht4(GenBank登录号为KR049247~KR049250)。序列分析表明,克隆所得序列无内含子,编码的几丁质酶属于ClassⅠb类型,也属于糖苷水解酶第19家族,是胞外分泌蛋白且兼具溶菌酶活性。SDS-PAGE分析表明,重组质粒pE-Chi能在BL21(DE3)中表达一个33kDa左右的特异蛋白。qRT-PCR分析表明,这5种几丁质酶基因在小麦根、茎和叶中均有表达,但在不同器官中表达量差异较大,其中,叶中表达量最高,根中次之,茎中最低;同时,这5种几丁质酶基因在同一器官中表达量大小具体表现为Cht4Cht2Cht3Cht1Chi-3。选取相对表达量最高的Cht4基因验证其对真菌性病害的抗性反应,结果表明,在条锈菌胁迫下,Cht4基因在抗病材料92R137中的表达量显著高于感病材料铭贤169,并且均高于同等条件下接ddH2O的表达量。本研究扩增到的几丁质酶基因在小麦中组成型表达,说明其参与了小麦的正常生长发育过程;Cht4基因的表达受条锈菌诱导,推测其可能参与了小麦叶部抗条锈菌的防御反应。     

小麦穗发芽抗性分析及相关分子标记检测

小麦成熟期遭遇穗发芽会严重影响小麦的产量和品质。为了解徐州主要栽培品种的穗发芽抗性及其分子机制,用整穗发芽法、籽粒发芽法考察了5个徐州地区主要推广小麦品种的籽粒休眠和发芽特性,并用10个分子标记对其穗发芽性状进行解析。结果表明,供试品种间整穗发芽率、发芽率和萌发指数均存在不显著、显著或极显著差异。徐农029的整穗发芽率最低,为3.02%,烟农19的整穗发芽率最高,达68.80%。徐农029的发芽率和萌发指数分别为41.00%和21.43%,均极显著低于其父本矮抗58(71.67%、53.10%)和母本淮麦20(89.67%、61.00%),周麦18和烟农19的发芽率均为99.33%,而烟农19的萌发指数(83.95%)高于周麦18的萌发指数(81.43%)。分子标记检测发现,徐农029和淮麦20属于Vp1Bc型抗穗发芽; Xgwm282标记在5个品种中呈2种带型,与穗发芽抗性关系密切。另外,8个抗穗发芽相关分子标记不能很好区分上述5个品种的抗穗发芽特性。     

普通小麦TaTPR1基因的克隆及表达分析

具有TPR基序的蛋白质被认为能够介导蛋白质间的相互作用,并且参与多种生物学过程,如细胞周期调控、转录调控、过氧化物酶等蛋白质的运输、信号传导和蛋白质折叠等。为了在小麦分子育种研究中获得更多有价值的候选基因,本研究采用电子克隆和RT-PCR方法从小麦中克隆得到1个TPR类基因,命名为TaTPR1。该基因ORF长度972bp,推测编码包含323个氨基酸残基的蛋白,相对分子质量34.9kD,理论等电点为5.89。氨基酸序列分析表明,该蛋白在142~207区和207~274区分别含有TPR类基因家族特有的保守结构域(TPR_16和TPR_11)。进化和聚类分析表明,小麦TaTPR1基因与粗山羊草AtTPR15基因、乌拉尔图小麦TuTPR15基因的亲缘关系较近,蛋白相似度分别为91.28%和91.55%。Real-time PCR表达特性分析显示,该基因为组成型表达,在根、茎、叶中均表达;幼苗期茎中表达量较高,随幼苗的生长,茎中表达量上调显著;该基因表达受高盐的强烈诱导,也受水分、低温和外源ABA胁迫诱导。     

光照对小麦的春化效应及其机制初探

为解析光照对春化过程的影响及其机制,以中麦175为材料,比较了光照春化及暗春化28 d时该品种开花时间的差异,并对春化前、春化7 d、14 d、21 d和28 d时,两种春化条件下小麦叶片中春化及光周期相关基因进行了real-time PCR分析。结果表明,与暗春化相比,光照春化使小麦提前开花19.73 d;与春化、光周期相关的基因（TaVRN1、TaVRN2、TaVER2、TaVIL1、TaVIL2、TaVIL3、TaCO1、TaCO2、TaPPD1、TaGI1、 TaLHY和TaTOC1）在光照春化条件下的表达水平较高,这可能是光照春化导致小麦提早开花的主要原因之一,也说明小麦中可能存在未知的TaVRN1调控因子,这些调控因子同时受到光照和低温条件的调控。     

小麦全蚀病抗性与根部性状的关系

为提高小麦抗全蚀病育种进程,利用菌饼接菌法,检测并分析了46个小麦品种（系）在温室条件下对全蚀病的抗性及其与根部性状的关系。结果表明,46个小麦品种（系）对全蚀病的抗性存在较大差异,其中,烟农23和良星66对全蚀病表现免疫,西藏半野生小麦、川农17和3份小麦-华山新麦草衍生后代表现高抗。小麦根部的根长、分叉数、根尖数与小麦全蚀病病情严重度呈显著正相关,相关系数(R²)分别为0.438、0.521和0.896;小麦根平均直径与病情严重度呈显著负相关,相关系数为-0.466。说明根系越小的小麦品种（系）对全蚀病的抗性越强。     

小麦种质资源耐深播性评价体系研究

为建立准确、简单易行的种质资源耐深播评价体系,以15份耐深播能力存在不同程度差异的小麦种质为材料,在大田环境下,研究6个播种深度(5 cm、7 cm、9 cm、11 cm、13 cm、15 cm)下小麦出苗率、出苗时间、苗高、地中茎长、胚芽鞘长、胚芽鞘横截面积及初生根长的差异,筛选小麦耐深播评价的最佳播种深度及其密切相...     

Effects of two novel Wx-A1 alleles of common wheat (Triticum aestivum L.) on amylose and starch properties

Common wheat (Triticum aestivum L.) has three Wx proteins (Wx-A1, Wx-B1, and Wx-D1), which are granule-bound starch synthases I and are responsible for the amylose synthesis of flour starch. The effects of two novel Wx-A1 proteins identified by gel electrophoresis on amylose content and starch properties were analyzed. The variant Wx-A1 protein coded by the Wx-A1i allele was present in smaller amounts and produced less amylose (7.3%) compared to standard lines with the Wx-A1a allele (21.5%). Wx-A1i generated altered starch properties; greater swelling power (SP), glucoamylase digestibility, starch paste clarity, and gelatinization enthalpy in differential scanning calorimetry. The starch from Wx-A1i also showed an altered pasting profile on a Rapid Visco-Analyzer, greater peak viscosity, smaller final viscosity, and lower pasting temperature. The Wx-A1i allele is a novel genetic resource for reducing amylose content in wheat. The other Wx-A1 protein coded by the Wx-A1j allele showed a more basic isoelectric point compared to Wx-A1a on an electrophoretic gel. The amylose content of Wx-A1j did not differ from standard Wx-A1a. Starch SP, paste clarity, and glucoamylase digestibility also suggested that Wx-A1j produced amylose as much as Wx-A1a.     

小麦 TaCSL1基因的克隆及表达模式分析

Clavaminate Synthase-Like（CSL）是生物体内的一种氧化还原酶,可催化氨基酸羟基化。为初步了解小麦CSL基因并探究其相关生物学功能,利用同源克隆的方法,以拟南芥 At3g21360（GenBank Accession：NC_003074.8）基因CDS序列为探针搜索小麦基因组核酸序列数据库,得到小麦A、B、D三个亚基因组上的部分同源基因序列。对上述三条序列的全长与编码区进行克隆和测序,经生物信息学分析,发现这三个基因编码的蛋白属于CSL家族。命名该基因为 TaCSL1,来自A、B、D三个亚基因组的部分同源基因分别命名为 TaCSL1-3A、 TaCSL1-3B、 TaCSL1-3D。实时荧光定量PCR分析表明,这三个部分同源基因在小麦不同生长发育阶段和不同组织部位均有表达,除叶鞘组织外,其相对表达水平在各时期叶片中均高于其他组织。分析该基因在小麦不同生长发育时期叶片的相对表达水平发现,该基因的相对表达量在幼苗期至孕穗期持续提高,抽穗期显著下降,开花后再次提高,生育末期降低。就三个部分同源基因的表达水平而言, TaCSL1-3A相对表达量均较低,而 TaCSL1-3B的相对表达量在孕穗期之前最高, TaCSL1-3D在孕穗期之后最高。本研究明确了 TaCSL1的时空表达特征,可为深入研究小麦氨基酸羟基化过程和植物抗病机理研究提供新思路。     

小麦CO-like基因TaCO9的克隆及分析

CO蛋白(CONSTANS)是光周期途径中重要的调控因子,为了从普通小麦中进一步挖掘COlike基因,利用同源克隆的方法得到与大麦HvCO9基因同源的小麦TaCO9基因。结果表明,在冬性品种西农889中,初步克隆得到TaCO9基因的三个同源序列,分别命名为TaCO9-1、TaCO9-2、TaCO9-3。其cDNA序列全长均为870bp,开放阅读框为1 977bp,编码289个氨基酸,含有CO-like蛋白家族典型的CCT结构域,但不含B-box结构域;而在春性品种中发现TaCO9-1序列的第二外显子区域有6个碱基的插入,利用中国春缺-四体材料将该序列定位于小麦的1A染色体,命名为TaCO9-1A。系统发育分析表明,TaCO9蛋白与水稻Ghd7及大麦HvCO9位于同一分支。空间结构分析表明,其CCT结构域的NF-YA2区域较为保守,而该区域与CCAAT box互作相关。本研究克隆得到的TaCO9基因可能是小麦CO-like基因家族的新成员,与大麦HvCO9基因的结构相似,可作为新的小麦光周期候选基因加以研究利用。     

小麦丙氨酸-乙醛酸转氨酶基因（ TaAGT2）的克隆、生物信息学预测及表达分析

光呼吸是植物细胞H_2O_2的重要来源,也是维持细胞氧化还原的重要成分,影响植物对生物和非生物逆境的应答,因此,挖掘与光呼吸有关的基因对提高植物的抗逆性具有重要意义。本研究以耐旱小麦品种青麦6号转录组数据为基础,通过RACE技术克隆得到小麦 AGT2基因的全长cDNA,将其命名为 TaAGT2,并对其进行了生物信息学预测及表达模式分析。结果表明, TaAGT2开放阅读框长1 434bp,编码477个氨基酸。该蛋白属于亲水性稳定蛋白,定位于线粒体中,二级结构以α-螺旋(42.14%)和无规则卷曲(32.91%)为主。 TaAGT2基因包含AAT-I基因族保守区域,与二穗短柄草 AGT2的相似性高达97%。通过qRT-PCR对基因 TaAGT2在不同组织中(根、茎和叶)及4种非生物胁迫(低温、ABA、干旱、高盐)下的表达特性进行分析,结果表明, TaAGT2在根、茎和叶中均有表达,茎中的表达显著高于根和叶,在不同胁迫条件下上调表达,表明该基因可能参与调控植物的抗逆反应。     

普通小麦TaADF8基因的克隆及表达分析

肌动蛋白解聚合因子(actin-depolymerizing factor,ADF)普遍存在于真核细胞中,为低分子量的肌动蛋白结合蛋白,在调控细胞内肌动蛋白纤维的聚合和解聚中起关键作用。为给深入研究TaADF8基因在小麦中的功能机理奠定基础,并为进一步丰富小麦ADF基因研究内容提供理论参考,本研究利用电子克隆策略从小麦品种CP53中克隆出TaADF8基因(GenBank登录号为KJ864962)后对其进行序列分析,并进一步采用荧光定量PCR(quantitative real-time PCR,qRT-PCR)技术对其在小麦不同组织间的表达差异及不同非生物胁迫下的表达模式进行分析。核酸序列分析表明,该基因全长695bp,拥有完整的ORF,编码142个氨基酸。氨基酸序列分析表明,该蛋白含有保守的ADF同源区和PIP2结合结构域,且在氨基端有核定位信号。进化和聚类分析表明,小麦TaADF8基因与大麦HvADF2基因、HvADF3基因和水稻OsADF3基因亲缘关系较近,蛋白相似度分别为75.35%、93.66%和67.86%。qRT-PCR表达特性分析显示,该基因为组成型表达,在根、茎、叶、颖壳和雄蕊中均表达,且在根、叶和雄蕊中表达量较高;该基因表达受低温的强烈诱导,同时也受水分、高盐和外源脱落酸胁迫诱导。