【作者】 吴进东；

【导师】 李金才；

【作者基本信息】 安徽农业大学 ， 作物生理生态， 2013， 博士

【摘要】 高温和渍水是黄淮麦区南部和长江中下游麦区冬小麦(Triticum aestivum L.)生育中后期主要气象灾害因子，随着全球气候变暖，其发生程度及频数都逐渐增加，严重影响小麦产量和品质。氮素是小麦生长发育所必需的大量营养元素之一，合理的氮肥营养是缓解逆境胁迫，调控作物生长、群体发育、提高同化能力的重要措施。试验选用“烟农19”为材料，采用盆栽方式于2010-2012连续两个年度在研究了花后不同时期短暂高温渍水逆境胁迫对冬小麦生理生态、产量和品质的影响及其氮素调控效应，以期为黄淮南部麦区和长江中下游麦区冬小麦后期叶面喷肥防衰和抗渍高产栽培技术提供理论基础。主要研究结果如下：1花后短暂高温渍水逆境对冬小麦植株生理的影响及其氮素调控（1）花后短暂高温胁迫、渍水胁迫、高温渍水双胁迫均使冬小麦膜脂过氧化程度加剧，旗叶SOD、POD、CAT活性短暂小幅升高后随即显著下降， MDA含量显著高于对照，加速植株衰老。上述逆境胁迫均显著降低小麦根系活力，抑制叶绿体生物合成，叶片叶绿素含量下降，Pn、Gs持续低于对照，Ci持续升高，高温使Tr短暂升高后显著降低，渍水、高温渍水双胁迫均导致小麦旗叶Tr持续低于对照。（2）短暂高温和渍水胁迫互作显著，高温极显著地加重了渍水危害。各逆境胁迫对冬小麦植株生理各指标的不良效应大小为高温渍水双胁迫>渍水胁迫>高温胁迫；籽粒形成期逆境不良胁迫效应显著大于籽粒乳熟期胁迫。（3）氮素补偿缓解各逆境的不良胁迫。（4）旗叶Ci的变化与Pn变化趋势相反，说明光合作用的主要限制因素是非气孔因素，由气孔关闭造成的影响较小。2花后短暂高温渍水逆境对冬小麦灌浆特性及产量构成因素的影响及其氮素调控（1）花后短暂高温胁迫、渍水胁迫、高温渍水双胁迫均可显著减小冬小麦籽粒体积，降低灌浆速率，缩短灌浆历期，减少穗粒数，降低千粒重与产量，而对穗数无显著影响。（2）高温与渍水交互作用显著，高温加重渍水逆境危害；各逆境不良影响程度为高温渍水双逆境>渍水逆境>高温逆境；籽粒形成期逆境的不良效应比籽粒乳熟期大。（3）氮肥补偿可显著增加冬小麦籽粒体积，提高灌浆速率，延长灌浆历期，提高千粒重与产量，对穗数、穗粒数无显著影响。（4）花后短暂高温渍水情况下，小麦最终千粒重与各灌浆速率参数的相关性大于与各灌浆历期参数的相关性，决定千粒重的主要是籽粒灌浆速率，而各历期参数属次要影响；冬小麦产量与中后期灌浆速率的关联性大于与渐增期灌浆速率的关联性。3花后短暂高温渍水逆境对冬小麦籽粒蛋白质合成与积累的影响及其氮素调控（1）花后短暂高温胁迫下小麦旗叶GS、籽粒GPT活性先小幅升高，不久显著下降；花后短暂渍水胁迫、高温渍水双胁迫均持续降低旗叶GS、籽粒GPT活性。高温降低籽粒蛋白质累积量，提高蛋白质及各组分含量，降低谷醇比。渍水则降低蛋白质累积量、蛋白质及各组分含量、谷醇比。高温渍水双胁迫提高了醇溶蛋白含量，降低了蛋白质累积量、谷蛋白含量和谷醇比，对清蛋白、球蛋白含量无显著影响。（2）高温和渍水对旗叶GS、籽粒GPT活性、蛋白质累积量的交互效应显著，对蛋白质及各组分含量与谷醇比交互效应不显著。各因素对旗叶GS、籽粒GPT活性、蛋白质累积量、谷醇比的影响程度为高温+渍水>渍水>高温，对蛋白质及组分含量的影响程度为渍水>高温+渍水>高温。籽粒形成期逆境胁迫对旗叶GS、籽粒GPT活性、蛋白质累积量的不良效应显著大于籽粒乳熟期的不良效应，而两时期对蛋白质及组分含量、谷醇比的效应差异不显著。（3）叶面喷氮补偿氮素营养，提高旗叶GS、籽粒GPT活性、籽粒蛋白质累积量、蛋白质含量、清蛋白含量、球蛋白含量及谷蛋白含量，但对醇溶蛋白含量无显著影响，提高谷醇比。（4）相关分析表明，试验中蛋白质合成关键酶活性与籽粒产量、蛋白质累积量、谷醇比显著正相关，与蛋白质含量无显著相关。4花后短暂高温渍水逆境对冬小麦籽粒淀粉合成与积累的影响及其氮素调控（1）花后短暂高温胁迫、渍水胁迫、高温渍水双胁迫均抑制了淀粉合成原料蔗糖向籽粒的供应，也抑制了淀粉合成系统酶活性，从而导致籽粒淀粉积累量降低。花后高温胁迫下小麦籽粒SS、ADPGPPase、SSS、GBSS活性先小幅升高，不久显著下降。花后渍水胁迫、高温渍水双胁迫均持续降低籽粒SS、ADPGPPase、SSS、GBSS活性。花后高温对籽粒GBSS活性的不良影响比对籽粒ADPGPPase、SSS活性的不良影响小，导致淀粉含量下降，直链淀粉含量上升，支链淀粉含量下降，支直比下降。渍水造成籽粒淀粉含量、支链淀粉含量显著低于对照，对直链淀粉含量影响不显著，支直比下降。（2）高温渍水对淀粉合成相关指标的互作显著，可见高温极显著地加重了渍水危害。籽粒形成期逆境胁迫降低了小麦籽粒蔗糖含量，籽粒SS、ADPGPPase、SSS、GBSS活性，淀粉累积累量下降，不同时期对淀粉组分含量、支直比影响不显著。（3）氮素补偿提高淀粉合成相关酶的活性、淀粉累积量与支直比，降低直链淀粉含量，对淀粉含量，支链淀粉含量无显著影响。5花后短暂高温渍水逆境对冬小麦面粉加工品质的影响及其氮素调控（1）花后短暂高温提高了面粉的湿面筋含量，改善了粉质参数、拉伸参数，而对糊化温度影响不显著，对其它淀粉糊化参数产生不利影响。花后短暂渍水降低了湿面筋含量，粉质参数、拉伸参数均变劣，对糊化温度影响不显著,提高了其它淀粉糊化参数。由于高温逆境和渍水逆境对小麦籽粒蛋白质含量及组分与淀粉含量及组分具有“对冲”效应，导致与对照相比较，高温渍水双逆境对面粉的淀粉糊化参数产生不利影响，但改善了拉伸参数，而对湿面筋含量与粉质参数无显著影响。(2)不同时期逆境对湿面筋含量与粉质参数、拉伸参数、稀懈值、糊化温度的影响差异不显著，籽粒形成期逆境对峰值粘度、低谷粘度、最终粘度、反弹值显著大于乳熟期逆境。（3）叶面氮肥补偿提高除糊化温度的其它糊化参数、湿面筋与粉质参数、拉伸阻力，对糊化温度、拉伸面积、延伸度、拉伸比例无显著影响。在花后短暂高温渍水逆境下，叶面氮素补偿主要通过缓解小麦植株早衰，提高蛋白质、淀粉合成相关酶活性而改善蛋白质、淀粉含量与品质,是缓解逆境不良效应，提高小麦产量与品质的有效途径。更多还原

【Abstract】 High temperature and waterlogging in the middle and later growing season are the major limiting factors for winter wheat (Triticum aestivum L.) yield and quality improvement in the Southern Huanghuai and Yangtze Valley region of China. Along with the global climate change, both the magnitude and frequency of high temperature and waterlogging are predicted to increase. Nitrogen is one of necessary macro-nutrient for the wheat growth and development. Reasonable application of nitrogenous fertilizers is an important way to alleviate the negative effects of stress, regulate crop growth and development and improve its assimilation capacity. Field experiments with ’Yannong19’(Triticum aestivum L.) by pot method were conducted to investigate the effects of high temperature and waterlogging on physiology and ecology, yield, quality of winter wheat and its nitrogen management in continuous growing seasons from2010to2012in order to provide basic theory for high yield cultivation technology to alleviate high temperature stress, waterlogging stress and senescence of winter wheat by spraying foliar nitrogen in later growth season in the Southern Huanghuai and Yangtze Valley region of China. The main contents and results were below:1Effects of transient high temperature and waterlogging after anthesis on physiology of winter wheat and nitrogen management:(1) Compared with control, high temperature stress, waterlogging stress, high temperature+waterlogging double stress after anthesis all increased degree of membrane lipid peroxidation, resulting in activities of SOD, POD, CAT of winter wheat flag leaf increasing slightly briefly and soon dropping significantly and MDA contents under each adverse stress being always higher than those of control, accelerating plant senescence. Each adverse stress after anthesis decreased the wheat root activities, chlorophyll contents, Pn, Gs of winter wheat flag leaf and their Ci rised continually. High temperature stress decreased wheat flag leaf Tr significantly after the briefly rise and waterlogging stress and high temperature+waterlogging double stress both decreased it continually.(2) There were significant interactions between high temperature and waterlogging and high temperature deteriorated the negative effects of waterlogging. According to degree of negative effects in indexes of physiology in winter wheat, the order was waterlogging+high temperature> waterlogging> high temperature. Negative effects of each adverse stress in grain formation stage were higher than those of in milk-ripe stage.(3) Spraying foliar nitrogen alleviated negative effects of each adverse stress.(4) The change trends of Ci and Pn in the flag leaf were opposite in the experiment, which indicated that the factors affecting photosynthesis should be non-stomatal factors.2Effects of transient high temperature and waterlogging after anthesis on grain filling characteristics and yield components of winter wheat and nitrogen management:(1) Be consistent with changes of physiological indexes, transient high temperature stress, waterlogging stress, high temperature+waterlogging double stress after anthesis all significantly reduced1000-grain volume, grain filling rate, grain filling duration,1000-grain dry weight, grains per spike and yield of winter wheat, but had no significant effect on spikes.(2) There were significant interactions between high temperature and waterlogging and high temperature deteriorated the negative effects of waterlogging. According to degree of negative effects in indexes of yield components in winter wheat, the order was waterlogging+high temperature> waterlogging> high temperature. Negative effects of each stress in grain formation stage were higher than those of in milk-ripe stage.(3) Spraying foliar nitrogen improved1000-grain volume, grain filling rate, grain filling duration,1000-grain dry weight, and yield of winter wheat，but had no significant on spikes and grains per spike.(4) According to grey correlations between yield and grain filling parameters of winter wheat, the relationships with grain filling rate parameters were more significant than those with grain filling duration parameters and each treatment affected yield of winter wheat mainly by affecting grain filling rates in middle and later grain filling stages.3Effects of transient high temperature and waterlogging after anthesis on grain protein synthesis and accumulation of winter wheat and nitrogen management:(1) High temperature stress after anthesis increased slightly activities of flag leaf GS, grain GPT in winter wheat first and soon dropped significantly and waterlogging stress, high temperature+waterlogging double stress both decreased them continually. High temperature reduced protein accumulation, ratio of Glu/Gli, while improved protein content and each protein ingredient content. Waterlogging reduced protein accumulation, protein content and each protein ingredient content, ratio of Glu/Gli. High temperature+waterlogging double stress improved gliadin content, reduced protein accumulation, glutelin content, ratio of Glu/Gli, had no significant effect on contents of albumin, globulin.(2) The interactions between high temperature and waterlogging of flag leaf GS, grain GPT, protein accumulation were significant but those of protein content and each protein ingredient content, ratio of Glu/Gli were not significant. According to degree of negative effects on indexes of grain protein synthesis in winter wheat, the orders of flag leaf GS, grain GPT, protein accumulation, ratio of Glu/Gli were waterlogging+high temperature> waterlogging> high temperature and those of protein content and each protein ingredient content were waterlogging> waterlogging+high temperature> high temperature. The negative effects on flag leaf GS, grain GPT, protein accumulation of each stress in grain formation stage were higher than those of in milk-ripe stage, but there were no significant different on protein content and each protein ingredient content between two stages.(3) Spraying nitrogen compensated nitrogen nutrition, improved flag leaf GS, grain GPT, protein accumulation, protein accumulation, contents of protein, albumin, globulin and glutelin, had no significant effect on gliadin content, and led to improving ratio of Glu/Gli.(4) Correlation analysis indicated that correlation coefficients between activities of key regulatory enzymes involved in protein formation and grain yield, protein accumulation, ratio of Glu/Gli were significant, while correlation coefficient with protein content was not significant.4Effects of transient high temperature and waterlogging after anthesis on grain starch synthesis and accumulation of winter wheat and nitrogen management:(1) High temperature stress, waterlogging stress, high temperature+waterlogging double stress after anthesis all inhabited the sucrose, which is starch synthesis materials, supplying to grain, and inhibited the activities of starch synthesis enzymes which resulted in the decrease of grain starch accumulation. High temperature stress after anthesis increased slightly activities of SS、ADPGPPase、SSS、GBSS in winter wheat grain first and soon dropped significantly and waterlogging stress, high temperature+waterlogging double stress all decreased them continually. Compared with the reductions of grain ADPGPPase, SSS activities, high temperature decreased GBSS activities relatively slight, which resulted in increasing amylose content and decreasing amylopectin content, ratio of amylopectin and amylase. Waterlogging decreased grain starch accumulation, starch content, amylopectin content, and ratio of amylopectin and amylose, had no significant effect on amylose content.(2) There were significant interactions between high temperature and waterlogging. Adversity stress in grain formation reduced SS content, grain SS, ADPGPPase, SSS, GBSS activities, starch accumulation. There were no significant different on starch content and each starch ingredient content, ratio of amylopectin and amylase between two stages.(3) Spraying nitrogen improved SS content, grain SS, ADPGPPase, SSS, GBSS activities, starch accumulation, ratio of amylopectin and amylase, decreased content of amylose, and had no significant different on starch content and amylopectin content.5Effects of transient high temperature and waterlogging after anthesis on flour processing quality of winter wheat and nitrogen management:(1) High temperature increased flour wet gluten content, improved farinograph parameters, extensograph parameters, had no significant effects on pasting temperature, and had negative effect on other pasting parameters. Waterlogging reduced flour wet gluten content, had negative effect on farinograph parameters, extensograph parameters, had no significant effects on pasting temperature and increased other pasting parameters. Due to high temperature stress and waterlogging stress have a "hedge" effect in contents of starch and its composition, protein and its composition of wheat grain, high temperature+waterlogging double stress had an adverse effects on starch pasting parameters, but improved grain extensograph parameters, and had no significant effects on wet gluten content and farinograph parameters.(2) The negative effects on peak viscosity, hold trough, final viscosity, setback of each stress in grain formation stage were larger than those of in milk-ripe stage, but those of breakdown,pasting temperature,wet gluten content, farinograph parameters and extensograph parameters were not significant.(3) Spraying nitrogen improved wet gluten content, farinograph parameters, and esistance to extension, pasting parameters except pasting temperature and had no significant effects on pasting temperature, extension area, extensibility, and extension ratio.Spraying nitrogen improved grain yield and quality of winter wheat mainly through alleviating wheat plant senescence, improving the activities of enzymes related to synthesis of protein, starch and it was an effective way to alleviate negative effects of high temperature stress and waterloging stress.更多还原