小麦水旱地品种回交二代农艺性状改良效应分析

为研究干旱条件下小麦水旱地品种回交后代群体农艺性状改良效应,本研究以旱地品种‘长6878’为供体亲本、水地品种‘济麦22’为轮回亲本获得的回交二代（BC₂）后代材料,对其株高、穗长、穗下节间长、分蘖数、小穗数、穗粒数、单株生物学产量、单株粒重、千粒重、经济系数等10个农艺性状进行相关、聚类和主成分分析。结果显示,回交后代材料在株高、穗长、穗下节间长、分蘖数等性状偏向于轮回亲本‘济麦22’,同时在小穗数、穗粒数、单株生物学产量、单株粒重、千粒重、经济系数等性状中存在超亲效应。相关分析表明,经济系数与单株粒重显著正相关,而单株粒重又与株高、穗长、分蘖数、小穗数、穗粒数、单株生物学产量、千粒重等7个性状达极显著正相关水平。在欧式距离40处,BC₂群体分为4类,以轮回亲本‘济麦22’为核心的第Ⅱ类占BC₂代总数的30.5%,供体亲本‘长6878’单独划为第Ⅳ类;在欧式距离45处将第Ⅰ类（占BC₂代总数的58%）和第Ⅱ类合并成一个新的类群,即群体中88.5%的BC₂单株和轮回亲本划分为一类。主成分分析得到5个主成分因子对BC₂代农艺性状变异累计贡献率为85.51%,并筛选出综合得分高的10个株系,可作为后代重点选育。综合以上结果,在BC₂代已经取得了良好的农艺性状定向遗传改良效应,为回交定向改良小麦抗旱水分高效利用和选育新品种提供理论依据和技术支撑。     

耐盐小麦品种在干旱条件下的农艺性状分析

干旱、盐碱等逆境胁迫是影响小麦产量的主要自然灾害, 培育抗旱抗盐高产小麦品种是我国北方小麦育种的主要任务之一。本文对来自新疆的"新冬26"和来自河北沧州的"沧麦6001"、"沧麦6002"、"沧麦6003" 共4个小麦品种, 进行了苗期耐盐性初步鉴定, 了解4个耐盐小麦品种的耐盐能力差异, 并对2010-2011年2年中大田干旱条件下4个小麦品种的相关农艺性状进行了分析, 为小麦耐盐、耐旱品种改良与遗传育种提供参考信息。研究结果表明, 在100 mmol·L^-1 NaCl处理下, "新冬26"的根与苗的相对生长量高于3个沧麦品种; 在200 mmol·L^-1 NaCl处理下, "沧麦6003"根与苗的相对生长量较高; 同时经过100 mmol·L^-1 NaCl处理后, 4个品种的根苗长度比均有所降低, 但"新冬26"在200 mmol·L^-1 NaCl处理下, 较100 mmol·L^-1 NaCl处理下根苗长度比增大, 说明这个品种对高盐胁迫具有一定的耐受能力。在大田干旱条件下, 耐盐品种"新冬26"与沧麦"6001"表现耐旱高产。进一步分析干旱条件对耐盐小麦品种农艺性状的影响, 对农艺性状相关性分析表明: 单株籽粒产量与分蘖、穗粒数、小穗数、单株生物学产量呈极显著正相关, 与经济系数呈显著正相关。多元回归分析表明: 分蘖、小穗数、穗粒数、单株生物学产量4个农艺性状决定了单株产量75.9%的变异。以上试验结果说明, 在筛选耐盐耐旱小麦品种时, 应考虑选择分蘖、小穗数、穗粒数、单株生物学产量等指标比较高的品种。     

抗旱冬小麦新品种晋麦105号选育报告

为了给山西省小麦生产提供抗旱、高产、优质小麦新品种,促进小麦更新换代,实现小麦持续增产稳产。以运旱20410为母本、运旱719为父本进行杂交,通过水旱交叉生态选择、多环境多点鉴定等手段,采用系谱法成功选育出了抗旱冬小麦新品种晋麦105号。2017 — 2019年参加山西省南部中熟冬麦区旱地组品种区域试验, 2 a 13点(次)平均折合产量为4 396.28 kg/hm2,较对照品种晋麦47号增产6.7%。2018 — 2019年度参加山西省南部中熟冬麦区旱地生产试验, 7个试点平均折合产量为4 158.77 kg/hm2,比对照品种晋麦47号增产6.1%。该品种株高73.6 cm,穗长6.8 cm,成穗数480.0万穗/hm2,穗粒数31.0粒,千粒重38.5g;中感条锈病,中感叶锈病,中感白粉病。适宜在山西省南部麦区旱地、黄淮旱地麦区、陕西渭北旱塬麦区及同类生态类似区种植。     

大豆引种筛选鉴定研究

对来自各省的14个大豆品种进行了产量比较试验和农艺性状的鉴定,并对与产量相关的因素进行了相关分析,结果表明:‘贡2009-2’、‘489-1’、‘中黄39’、‘浙0305-3’、‘浙H0322-1’和‘南06-44’的丰产性极显著优于对照,生育期适中,农艺性状好,适合在重庆地区春播;相关分析表明,单株粒重与产量极显著相关,百粒重、单株荚数和单株粒数与产量相关密切,可通过增加单株粒重和百粒重来提高大豆产量。     

热胁迫对不同小麦品种灌浆速率的影响

为了给小麦高产稳产和耐热新品种选育提供依据,对北部冬麦区和黄淮冬麦区的12个推广小麦品种在正常及热胁迫下的产量、千粒重及灌浆过程进行了研究。试验于2014—2015年度在河北省辛集马兰农场进行,用大棚升温作为热胁迫处理,在小麦灌浆期对不同品种在正常及热胁迫处理下的灌浆速率进行测定,收获后测定产量和千粒重,并计算热感指数。结果表明,‘中麦175’、‘衡4399’、‘衡4444’、‘CA0816’和‘中麦875’在自然生长及热胁迫处理下有较高的产量。在小麦灌浆中后期的籽粒快增期及缓增期发生的热胁迫会通过影响灌浆速率显著影响小麦的千粒重及产量。根据千粒重热感指数对不同小麦品种的耐热性进行评估,发现‘京冬8号’、‘CA0816’、‘CA1062’、‘中麦875’、‘中麦895’及‘衡4444’的千粒重热感指数1,是耐热性较好的品种;其他品种的千粒重热感指数≥1,是热敏感品种。对不同品种在正常及热胁迫条件下的灌浆速率进行分析,发现热胁迫对不同耐热性品种灌浆速率产生影响的起始时间不同,耐热性好的品种的灌浆速率在灌浆后期才会受到热胁迫的影响,热敏感品种在灌浆中期即受到热胁迫的影响。总之,‘CA0816’、‘中麦875’和‘衡4444’是丰产性和耐热性都较好的品种;‘衡4399’和‘中麦175’的千粒重热感指数一般,但产量在自然生长及热胁迫下均较高;‘京冬8号’耐热性好,丰产性略差。以上品种均可作为优异的耐热资源在育种中加以利用,在育种实践中需联合使用品种的产量数据和千粒重热感指数来评估该品种在耐热性育种中的价值。     

水稻农艺性状的耐盐碱鉴定及比较分析

为探究水稻品种耐盐碱的差异性,选用18个水稻品种(系)进行田间农艺性状耐盐碱鉴定,以不同农艺性状的相对抑制率作为耐盐碱性评价指标,分析产量性状耐盐碱性和其他农艺性状耐盐碱性及其相关关系,筛选出可作为水稻耐盐碱鉴定的指标,建立以产量为主、其他农艺性状为辅的田间耐盐碱鉴定体系。结果表明:盐碱胁迫对水稻的产量、抽穗期、株高、分蘖数、穗长、穗数、穗粒数、千粒重等农艺性状均有显著的抑制作用,且品种间耐盐碱性差异显著;盐碱胁迫对水稻不同农艺性状的抑制程度有所不同,对单株平均穗数影响最大,对抽穗期抑制作用最小;通过简单相关分析筛选出株高相对抑制率、分蘖数相对抑制率、穗粒数相对抑制率、千粒重相对抑制率4个与产量相对抑制率显著相关的指标,可作为水稻品种耐盐碱鉴定的参考指标。     

长江中下游麦区小麦新品种穗发芽抗性及鉴定方法研究

为鉴定长江中下游麦区主推品种的穗发芽(PHS)抗性,筛选高抗穗发芽种质资源,探讨简单、高效测定穗发芽的方法,本研究以长江中下游麦区小麦新品种为试验材料,利用田间穗发芽法(GP)、降落值(FN)法和搅拌值(SN)法对本麦区小麦新品种的穗发芽抗性进行鉴定。结果表明,田间穗发芽率与FN、SN呈极显著负相关,FN法与SN法均可作为评价小麦穗发芽抗性的有效方法。SN与FN呈极显著正相关,相关系数为0.957,SN法测试时间短,样品用量少,品种间SN变幅大,能更准确地鉴定穗发芽抗性差异小的品种。聚类分析结果表明,白皮小麦鄂麦170、襄麦35、红皮小麦宁麦19、宁麦21、信麦8811、皖西麦0638和宁麦23为一类,田间穗发芽率最高为62.36%,FN150 s,SN100 cp,穗发芽抗性弱;扬麦25、扬麦23、扬富麦101、扬麦16、苏科麦1号、扬麦20、宁麦22、镇麦10号、扬麦21为二类,田间穗发芽率小于1%,FN250 s,SN900 cp,穗发芽抗性强;其他品种抗性中等,为三类。综上,SN法是鉴定穗发芽抗性的高效方法之一,可把SN900 cp作为抗穗发芽指标。本研究为长江中下游麦区抗穗发芽种质资源的筛选及穗发芽抗性育种提供了科学依据。     

激光诱变小麦数量性状的相关研究

本试验研究钕玻璃激光,CO_2激光以及钕玻璃激光和CO_2激光复合处理诱变小麦数量性状的遗传效应和相关性。结果表明,各处理后代主要农艺性状对单株产量的最优多无线性回归方程的显著自变数为穗粒重、单株有效穗数、穗粒数和株高等,且多元相关系数极显著。通径分析表明,小麦激光后代的选择应注意穗粒重、单株有效穗数和穗粒数等综合性状。     

甘蓝型油菜单株有效角果数和产量相关性分析

为了摸清油菜单株有效角果数和产量二者间的关系,以2017—2018年试验数据为准,统计了国家油菜区域试验16个组的甘蓝型油菜品种(系)的单株有效角果数与产量,并进行相关性分析。结果表明,长江上游区(ABCD组)、长江中游区(ABCD组)、长江下游区(ABCD组)、黄淮区(AB组)、云贵高原组和早熟组共计16个组的甘蓝型油菜品种(系)的油菜单株有效角果数与产量的相关系数分别为0.614 92、0.211 71、0.216 44、0.310 77、-0.039 27、0.396 74、0.094 32、0.551 07、-0.347 39、-0.040 48、0.290 50、-0.392 88、-0.424 32、0.046 77、0.618 13和0.738 37,即长江中游区A组和长江下游区AD组的油菜产量与单株有效角果数呈低度线性负相关;长江下游区B组和黄淮区A组呈显著性负相关;长江上游区BCD组、长江中游区BC组、长江下游区C组和黄淮区B组呈低度线性相关;长江上游区A组、长江中游区D组和云贵高原组呈显著性相关;早熟组呈高度线性相关。     

大麦早熟突变系高产基因型特征

运用通径分析和逐步回归相结合的统计方法 ,研究迟熟品种苏农 90 5 2的 3 6个早熟突变系的 8个农艺性状之间的遗传相关和各自的遗传参数 ,以及高产基因型特征。结果表明 :1 生育期较亲本提早的幅度为 2～ 1 3d,产量性状的突变范围较大 ;2 生育期与每穗粒数呈极显著遗传相关 ;3 影响单株产量的因子 ,按直接作用大小排列为 :单株有效穗 >千粒重 >每穗总粒数 >结实率 ,即早熟突变系高产基因型特征首先是多穗 ,其次是大粒 ,早熟高产品种的选育必须采取两高 (穗数、粒重 )一低 (粒数 )育种策略 ;4 早熟突变系的千粒重和生育期有较高的广义遗传力 ,单株有效穗和单株产量广义遗传力较小 ,遗传变异系数和遗传进度较大     

含醇溶蛋白小麦回生抗性直支链淀粉性质分析

为研究含醇溶蛋白小麦回生抗性直支链淀粉性质,该文采用醇溶法从小麦粉中提取醇溶蛋白,采用回生-酶解法分离得到小麦直、支链淀粉。通过可见光谱、红外光谱、X-射线衍射、差热扫描等方法分析研究醇溶蛋白对小麦直、支链淀粉回生的影响。结果表明,在凝胶化及回生过程中醇溶蛋白与淀粉相互作用,导致淀粉回生率增加。红外光谱研究表明,直链淀粉与醇溶蛋白在高压糊化后干燥或回生的条件下,醇溶蛋白的酰胺Ⅱ键伸缩振动从1 546 cm~(-1)降低至1 539 cm~(-1),即直链淀粉与醇溶蛋白通过氢键结合。X-射线衍射图谱显示在2θ衍射角为17°,19°,22°等的衍射峰没有发生明显变化,表明添加醇溶蛋白后,直、支链淀粉的晶型未发生明显改变。DSC结果显示直链淀粉与醇溶蛋白之间的氢键是在共同回生过程中产生的,样品中多晶结构和双螺旋结构共存。研究结果表明,淀粉中空间位阻小的6位碳原子上的羟基与醇溶蛋白中的脯氨酸和谷氨酰胺通过氢键结合,这种类型的氢键阻碍了α淀粉酶对淀粉的解离,即醇溶蛋白通过与淀粉形成新型氢键而促进了淀粉的回生。该研究提供了一种提高小麦淀粉的回生率的新技术,为进一步深入研究醇溶蛋白促进淀粉回生的机理提供理论支撑。     

不同品种混种对小麦产量及条锈病的影响

用"繁19"、"引11-12"、"川麦107"、"靖麦10号","青春55"、"46548-3"和"安96-8"7个不同小麦品种,组合成6个品种混种的群体,于2003～2004年、2004～2005年、2005～2006年在云南省曲靖市对其产量效应进行了多年多点试验,并在自然发病条件下,调查了6个品种混种群体对小麦条锈病发生程度的影响.结果表明,小麦品种混种的产量效应平均为+3.9%;小麦品种混种在产量上的正效应、0效应,负效应所出现的频率分别为69.4%、8.3%、22.3%;年份、地点等具体环境条件会影响小麦品种混种的产量效应.在小麦条锈病发病强度相对较高的年份,品种混种可降低条锈病病情指数.因此,品种混种在我国一些小麦产区有利用价值.     

Development of taxon-specific sequences of common wheat for the detection of genetically modified wheat

Qualitative and quantitative Polymerase Chain Reaction (PCR) systems aimed at the specific detection and quantification of common wheat DNA are described. Many countries have issued regulations to label foods that include genetically modified organisms (GMOs). PCR technology is widely recognized as a reliable and useful technique for the qualitative and quantitative detection of GMOs. Detection methods are needed to amplify a target GM gene, and the amplified results should be compared with those of the corresponding taxon-specific reference gene to obtain reliable results. This paper describes the development of a specific DNA sequence in the waxy-D1 gene for common wheat (Triticum aestivum L.) and the design of a specific primer pair and TaqMan probe on the waxy-D1 gene for PCR analysis. The primers amplified a product (Wx012) of 102 bp. It is indicated that the Wx012 DNA sequence is specific to common wheat, showing homogeneity in qualitative PCR results and very similar quantification accuracy along 19 distantly related common wheat varieties. In Southern blot and real-time PCR analyses, this sequence showed either a single or a low number of copy genes. In addition, by qualitative and quantitative PCR using wx012 primers and a wx012-T probe, the limits of detection of the common wheat genome were found to be about 15 copies, and the reproducibility was reliable. In consequence, the PCR system using wx012 primers and wx012-T probe is considered to be suitable for use as a common wheat-specific taxon-specific reference gene in DNA analyses, including GMO tests.     

小麦微波干燥特性及其对品质的影响

针对小麦热风干燥中存在的问题，运用微波试验装置，通过选择不同的干燥功率、物料铺放厚度及排湿风速，研究了小麦微波干燥特性及其对干后品质和能耗的影响。研究结果表明：小麦微波干燥主要处于恒速阶段，微波干燥对小麦品质有显著的影响，小麦籽粒的发芽率和SDS沉降值对微波处理的反应比较敏感，可以作为小麦热损伤的指标和小麦品质变化的检测指标，小麦微波干燥能耗主要受排湿风速影响。     

Crop rotation effects on yield of oilseed rape,wheat and barley and residual effects on the subsequent wheat

Economic conditions are forcing farmers to grow crops with high revenue leading to cereal-dominated crop rotations with increasing risk due to unfavourable preceding crops or preceding crop combinations. Based on a long-term field trial (1988–2001) with 15 different rotations including winter oilseed rape (OSR), winter wheat, winter barley, spring peas and spring oats, the effects of different preceding crops, pre-preceding crops and crop rotations on the grain yield of mainly OSR, winter wheat and winter barley were quantified. In the subsequent 2 years (2001/2002 and 2002/2003), winter wheat was grown on all plots in order to test the residual effects of the former crops (as preceding crops in 2002 and as pre-preceding crops in 2003) and crop rotations on growth, grain yield and yield components.

Unfavourable preceding crops significantly decreased yield of OSR, wheat and barley by 10% on average, however, with a large year-to-year variation. In addition, break-crop benefits in both crops, wheat and OSR, persisted to the second year. Wheat as preceding crop mainly decreased the thousand grain weight, and to a lesser extent, the ear density of the subsequent wheat crop. The amount of wheat yield decrease negatively correlated with the simple water balance (rainfall minus evapotranspiration) in May–July. In 2001/2002 and 2002/2003, the preceding crop superimposed the crop rotation effects, thus resulting in similar effects as observed in 1988–2001.

Our results clearly reveal the importance of a favourable preceding crop for the yield performance of a crop, especially wheat and OSR.     

小麦生长期土壤养分与根系活力变化及其相关性研究

研究了小麦生长期内土壤氮、钾与小麦根系活力变化及其相关性。结果表明,土壤碱解氮、速效钾和非交换性钾含量随小麦生育进程呈现有规律的变化;小麦根系活力呈现先增加,孕穗期峰值出现后迅速下降,成熟时根系活力下降到最低值的变化规律,不同施肥处理小麦整个生育期内根系活力大小顺序为:MNPK、NPK>NK>N、NP>CK、M。土壤碱解氮、速效钾、非交换性钾含量与小麦根系活力呈显著或极显著正相关,说明土壤N、K养分有效性的高低是影响小麦根系活力的重要因素。     

Evaluation of emmer wheat and other Triticeae for resistance to Russian wheat aphid

Summary During the winters of 1990/91 and 1991/92, 181 accessions of Triticum dicoccon Schrank from the CIMMYT gene-bank were screened in the field for resistance to Russian wheat aphid, Diuraphis noxia (Kurdjumov). Accessions were sown in hill plots of 10 seeds and artificially infested with D. noxia at the two-leaf growth stage. Hills were visually assessed for damage at tillering, booting and heading. Entries differed significantly in their reaction to D. noxia, and severity of symptoms increased with time. Twenty four of the entries were highly resistant to the aphid. In winter 1991/92, 807 accessions of wild and cultivated wheats (26 species) and synthetic hexaploids were screened similarly for resistance to D. noxia. A large number of A-genome species were resistant, while few D-genome species were identified as resistant. These newly discovered sources of resistance can be used to expand the genetic base of resistance to D. noxia in both bread (T. aestivum L.) and durum wheats (T. turgidum L. convar. durum (Desf.) Mackey).     

Comparative study of the effect of incorporated individual wheat storage proteins on mixing properties of rice and wheat doughs

The aim of this work was to compare the effects of incorporated wheat storage proteins on the functional properties of rice and wheat flours. The advantage of rice as a base flour compared to wheat is that it does not contain any wheat flour components and, therefore, has no interactive effect between wheat glutenin proteins. The incorporation of individual HMW glutenin subunit proteins (Bx6, Bx7, and By8) in different ratios had significant positive effects on the mixing requirements of both rice and wheat doughs. Reconstitution experiments using two x+y type HMW-GS pairs together with a bacterially expressed LMW-GS have been also carried out in this study. The largest effects of polymer formation and mixing properties of rice flour dough were observed when Bx and By subunits were used in a 1:1 ratio and HMW and LMW glutenin subunits in a 1:3 ratio. However, using the same subunit ratios in wheat as the base flour, these synergistic effects were not observed.     

Contribution of wheat endogenous and wheat kernel associated microbial endoxylanases to changes in the arabinoxylan population during breadmaking

Wheat kernel associated endoxylanases consist of a majority of microbial endoxylanases and a minority of endogenous endoxylanases. At least part of these enzymes can be expected to end up in wheat flour upon milling. In this study, the contribution of both types of these endoxylanases to changes in the arabinoxylan (AX) population during wheat flour breadmaking was assessed. To this end, wheat flour produced from two wheat varieties with different endoxylanase activity levels, both before and after sodium hypochlorite surface treatment of the wheat kernels, was used in a straight dough breadmaking procedure. Monitoring of the AX population during the breadmaking process showed that changes in AX are to a large extent caused by endogenous endoxylanases, whereas the contribution of microbial endoxylanases to these changes was generally very low. The latter points to a limited contamination of wheat flour with microbial enzymes during milling or to an extensive inactivation of these wheat flour associated microbial endoxylanases by endoxylanase inhibitors, present in wheat flour. When all wheat kernel associated microbial endoxylanases were first washed from the kernels and then added to the bread recipe, they drastically affected the AX population, suggesting that they can have a large impact on whole meal breadmaking.     

麦胚的微细化处理及其蛋白提取工艺优化

为了提高麦胚蛋白的提取率,采用锤式粉碎与胶体粉碎相结合的方法对脱脂麦胚进行微细化处理,再用碱提、超滤浓缩法提取制备麦胚蛋白,同时,通过Box-Behnken中心组合设计（CCD）及响应面分析（RSM）,建立了预测麦胚蛋白提取率的二次多项数学模型,优化了蛋白质的提取工艺。结果表明：微细化处理有利于麦胚蛋白的提取,其最佳条件是：麦胚粒度为23 μm,pH值9.5,提取温度51℃。蛋白提取率可达到68.6%。