【作者】 于立河；

【导师】 高聚林；

【作者基本信息】 内蒙古农业大学 ， 作物栽培学与耕作学， 2012， 博士

【摘要】 近年来,黑龙江省小麦生产中面积逐渐下降,全省不足600万亩,主要原因是品质较差、产量不高而导致的比较效益低,出现了播种量过大、施肥量过大等原因引起的倒伏、减产,以及小麦品质下降等问题。本研究为探讨位于高纬度的黑龙江省春小麦保优高产群体的调控途径,对比研究了生产上的不耐密(龙麦26)和耐密(克旱16)两个主栽春小麦品种,在施用化肥总量(纯量,N：P：K=1：1.1：0.5)105、180和225kg·hm-2三个水平下,采用300万株·hm-2-900万株.hm-2的不同群体密度,以及施用硅肥(纯量为15kg·hm～75kg·hm-2)对春小麦产量品质形成的影响。研究了不同施肥处理及不同肥密群体的光合特性和光合产物分配特点；器官水平的物质积累动态,以及氮磷钾大量元素的吸收和利用效率；从光合、衰老生理角度分析了产量和品质的形成过程及相互关系；最终进一步明晰了施肥和群体密度对黑龙江春小麦产量和加工品质的影响。结果表明：1.随群体密度的增加,叶面积指数高峰提前,由非气孔限制增加而引起的净光合速率的先降后增,各器官光合分配指数和干重均降低,最终导致根冠比下降;而增加施肥量,可通过降低气孔限制,而提高净光合速率,提高光合茎叶分配指数,而促进物质积累；不同基因型品种表现不同：与不耐密品种相比,耐密品种具有更大的根、叶光合分配指数,能在生育前期快速建成光合组织,并减缓了生育后期茎叶的早衰。2.群体密度的增加限制了小麦氮磷钾吸收与积累分配,降低了氮素农学效率,但提高了氮磷钾的生产效率和氮素收获指数；增加施肥量可通过提高钾的吸收与积累,而提高了茎叶的氮转移效率和氮素农学效率,并增加各器官的氮磷钾积累量,但施肥量的增加降低了氮素收获指数。3.高密度群体保障了耐密品种的收获穗数,进而获得较高的产量,而不耐密品种在高密度群体下收获穗数减少,单株产量显著降低,造成减产；增加施肥量可改善植株碳氮比,延缓籽粒形成阶段的叶片衰老,提高光合产物分配效率,通过提高耐密品种的穗粒数和不耐密品种的千粒重而增加产量。4.群体密度的增加,造成了叶片蒸腾速率的降低和可溶性糖的积累,叶片的衰老导致籽粒形成期的碳氮比失调,碳代谢加强,氮代谢减弱,千粒重增加,而穗粒数与籽粒的容重、面筋质量降低,直接导致面粉的粉质特性和面团拉伸特性变劣。而施肥量的增加可有效缓解高密度群体对籽粒品质和加工品质形成的不利影响5.基施硅肥增加了群体光合面积,60kg·hm-2(SiO2)以下,可明显改善叶片非气孔限制因素,提高叶片的光合速率,尤其是增加了花期以前群体的光合速率,提高了营养器官的光合分配指数与物质积累,而超过60kg·hm-2叶片的气孔导度和水分利用效率降低,花期以后耐密品种的光合产物向产量器官的运输效率下降。通过上述研究,形成了以合理群体密度和施肥量为主要技术的黑龙江省小麦生产“早窄密”高产栽培模式,并在生产中应用,获得了良好成效。6.基施硅肥促进了植株对氮磷钾元素的协同吸收与积累,不同程度的提高了氮磷钾元素的生产效率。但在不同类型品种上也存在器官水平的营养元素拮抗吸收与积累,尤其是降低了茎叶的氮素转移效率,而引起氮素收获指数的降低。7.基施硅肥促进了开花后叶片的光合碳同化,提高结实率与穗粒重,增加了耐密品种的收获穗数；同步提高了不耐密品种的花后源器官的氮代谢效率,改善了籽粒面筋质量,增加了面粉吸水率与面团断裂时间,增大了拉伸阻力和拉伸比例,但对耐密品种的品质影响较小。8.通过同源序列分析的方法在小麦全基因组上分离鉴定了4个与水稻硅转运基因高度同源蛋白所在家族成员,因其具有典型的Nod26-like内嵌蛋白保守结构域,该类具有6个螺旋状跨膜结构,分别命名为TaNIP2；1,TaNIP2；2, TaNIP4；1和TaNIP1:1.系统进化分析表明,除小麦TaNIP1:1蛋白被划为第一亚组NIP I外,其余3个TaNIP家族成员均被划归到第二亚组NIP Ⅱ。通过小麦不同组织和器官的qPCR表达结合小麦ESTs表达序列分析,表明小麦NIP基因按表达的部位可分成两类：其一为主要在花和花序中表达的,包括TaNIP1:1和TaNIP4:1；其二主要在根和茎中大量表达的,包括TaNIP2:1和TaNIP2:2。通过分析外施不同浓度硅对小麦株高、地上干重、地下干重和叶片中硅含量的影响,表明硅影响小麦的株高和地上干重,叶片中硅的累积与表型无明显相关性,而且外源施用不同浓度硅对小麦根部TaNIP2:1和TaNIP2:2基因的表达影响不大,其表达与叶片中硅的累积无明显相关性。更多还原

【Abstract】 In recent years, the wheat production area gradually declined in Heilongjiang province, total cultivated area is less than400thousand hm-2, poor quality and low output is the main reason of low benefit, so there are big sowing density and high fertilizer which result in many problems such as lodging, reduction, and poor wheat quality. This study discuss that the regulatory means of high quality and yield population for Heilongjiang province spring wheat which is located in the high latitude, and compare the influence of spring wheat yield formation quality of two main spring wheat varieties, including Longmai26and Kenan16, the population density and the content of silicon. The wheat population was designed from300to900million hm-2under each three levels of fertilization, including105,180and225kg·hm-2and five levels of the silicon contents were analyzed under above population density.To uncover the effects of fertilization and population density on yield and processing quality of spring wheat, the physiological indexes involved in photosynthesis and senescence and relationship between them were analyzed under three treatments for two strong-gluten and medium-gluten spring wheat varieties, including the fertilization content. The main physiological processes investigated comprised photosynthetic characteristics and allocation of photosynthetic products; matter accumulation in organs, absorption and utilization of nitrogen, phosphorus and potassium. The important results were as follows:As population density increases, the peak time of leaf area index advanced, the net photosynthetic rate caused by the increase of non-stomatal limitation showed decreases first and then increases, the index of photosynthesis allocation each organ and dry weight were reduced, resulting in the decrease of the root shoot ratio. The increase of fertilization could reduce the stomatal limitation with net photosynthetic rate increased, improve photosynthetic distribution index of stems and leaves, promote matter accumulation in each organ. Compared with the strong-gluten wheat, Medium-gluten wheat showed that higher distribution index in roots and leaves, improvement of rapid formation of photosynthetic tissue in the prophase of growth and delaying the senescence of stem and leaf at late stage of growth.Higher population density resulted in restricting the accumulation and transportation of nitrogen, phosphorus and potassium of upside wheat, reducing agronomic efficiency of nitrogen, and improving the production efficiency of nitrogen phosphorus potassium and nitrogen harvest index.Fertilization level and promote the potassium to shoot transport, improve leaf nitrogen transfer efficiency and nitrogen agronomic efficiency, increase the organ of nitrogen phosphorus and potassium accumulation amount, reduces the nitrogen harvest index, but the middle level of nitrogen phosphorus and potassium fertilizer under the highest production efficiency. Strong gluten wheat has higher than medium gluten wheat nitrogen transfer efficiency, therefore, the latter contents of nitrogen phosphorus and potassium were higher, while production efficiency of nitrogen phosphorus and potassium and harvest index of nitrogen were lower than the former.The total soluble sugar of wheat leaf showed a single-peak curve along with population density, the increasing fertilizers decreased C/N for strong-gluten wheat, and improved C/N for medium-gluten wheat; suitable high density population ensured the number of harvest spikes of medium-gluten wheat, but made the restriction of formation of strong gluten wheat individual yields. Under suitable planting density, the increase of fertilizer amount improved photosynthate distribution of the filling stage wheat, and delayed leaf senescence during maturity, the former was useful to increase number of grains, the latter was useful to increase grain weight.Population density increased accelerated the leaf senescence, resulted in stomatal closure, the improvement of antioxidant enzyme activity, reducing transpiration rate, and net photosynthesis rate by non-stomatal limitation. During grain formation stage, the ratio of carbon to nitrogen that because of total soluble sugar accumulation, while nitrogen content declined, suffered imbalance of cause the increase of1000-grain weight, and the decrease of grain number. The competition of previous both factors produced directly the results that the increase of bulk density, the decrease of gluten quality, and the deterioration of characteristics of flour quality and dough stretching in the process of the quality formation. The increase of fertilization amount could alleviate the adverse effects of the high population density effectively.Basic fertilizer silicon caused the change of the photosynthetic area and capacity synchronously, resulting in improving photosynthetic rate and distribution index of photosynthate before the flowering, stimulating matter accumulation of vegetative organs, but for the increase of distribution index of the nutritional organs generated the decrease of spike material input of medium-gluten wheat after flowering. Basic fertilizer silicon below60kg-hm2(SiO2), the photosynthetic rate was improved for the enhanced for the improvement of non-stomatal limitation factors mainly, while above60kg-hm-"(SiO2) the photosynthetic rate falled because of the decreases of stomatal conductance and water use efficiency.The efficiency of spring wheat of nitrogen, phosphorus and potassium was enhanced for basic fertilizer silicon, but nitrogen transfer efficiency of wheat stem and leaf was decreased to cause the depression of nitrogen harvest index. On the basis of silicon fertilizer, the synergistic effect of the absorption and accumulation of nitrogen phosphorus and potassium presented, as well as antagonism in the organ level, and antagonistic relationship exhibited larger differences with different cultivars.Basic fertilizer silicon helpfully increased the spike length and density to change the spike traits of strong-gluten wheat; simultaneously promoted wheat photosynthetic carbon assimilation after blossoming, and the total soluble sugar content from source organs, which could supply adequate nutrition for capacity formation. Silicon helped to coordinate source, reservoir, flow of spring wheat during kernel formation, thereby wheat yields were heightened for improving seed rate and grain weight. In addition, silicon facilitated the nitrogen metabolism of wheat source organs after flowering to improve flour processing qualities, for example, improvement of grain gluten quality and flour water absorption rate, elongation of dough breakdown time, tensile resistance and tensile ratio. For medium-gluten wheat, basic fertilizer silicon could expand production capacity of population by increasing the number of harvested spike, but affect quality of spring wheat un-significantly.Wheat protein family involved in silicon transporter was identified by analysis of homologous sequence. Four members of family with NOD26-like membrane integral structure named respectively TaNIP2;1, TaNIP2;2, TaNIPad4;1and TaNIP1;1. Phylogenetic analysis showed that, except for TaNIP1;1protein belonged to subgroup NIP Ⅰ, others were classified into subgroups NIPⅡ.TaNIPs expression patterns were divided into two groups based on analysis of ESTs database and qPCR. Both TaNIP1;1and TaNIP4;1expressed mainly in flower and inflorescence; while both TaNIP2;1and TaNIP2;2expressed principally in root and shoot. The effects of silicon on plant height and dry weight of upper plant significantly were found, and silicon accumulation in leaves almost depended on the silicon content. The expression change of TaNIP2;1和TaNIP2;2were weak exposured to the different content silicon, and the correlation with silicon accumulation was not obvious.更多还原