【作者】 解宝；

【导师】 王佺珍；

【作者基本信息】 西北农林科技大学 ， 草业科学， 2012， 硕士

【摘要】 生物能源是一种高效、洁净能源，将成为未来能源的重要组成部分。菊苣(Cichoriumintybus)是以菊粉果聚糖形式积累能量的一种多年生宿根菊科能源植物，不仅具有较高的饲用价值，同时作为一种替代能源植物也备受关注。菊科植物化学成分的复杂性和多样性均居植物界首位，并具有大量的次生化感物质。植物化感在除草杀虫、植物保护、生态恢复等领域都有广泛应用。微观上，植物化感可用于解释自然界中植物之间的相互作用，同时也为牧草种植的合理安排、间套轮作提供了重要的理论依据。因此，该类研究已成为生物科学植物领域的研究热点。本试验采用三因素三水平正交设计盆栽试验，包括3种受体植物（高羊茅（Festucaarundinacea）、三叶草（Trifoliumrepens）及紫花苜蓿（Medicagosativa）、3个氮处理（0.5N,N及2N）和3个pH水平（pH5.5，pH7.0及pH8.5）；包括9个处理，每个处理重复3次，共27个花盆。试验测定分二部分。试验一测定了氮与pH互作下供体植物叶片叶绿素（Chlorophyll）及丙二醛含量（Malondialdehyde，MDA）；过氧化氢酶（catalase，CAT)、过氧化物酶(Peroxidase，POD)、超氧化物歧化酶(SuperoxideDismutase，SOD)等活性的变化；及不同浓度菊苣渗透液对受体植物叶绿体、丙二醛、可溶性糖含量的变化影响。试验二通过菊苣水浸提液分别对菊苣、高羊茅、三叶草及紫花苜蓿种子萌发处理，测定其对种子发芽率、发芽势、发芽指数、活力指数、根长及茎长的影响；并运用液相色谱仪测定叶片及根提取液中相关化感物质的含量。通过以上试验，从而系统地对菊苣化感活性进行了定性及定量研究。试验取得的主要结果如下：1.在不同氮浓度处理时，菊苣叶片叶绿素和MDA含量无显著变化，而POD和SOD活性显著上升；在不同pH处理时，菊苣叶片叶绿素含量有显著变化，MDA含量无显著变化，而POD和SOD活性显著上升；氮与pH互作对菊苣生长有显著影响；菊苣叶片叶绿素含量在高氮低pH互作下最高，且随施氮量的增加而持续增加；MDA含量在高氮低pH互作下最低，且在氮或pH胁迫时变化甚微；POD和SOD活性在高氮高pH互作下活性最低，且在受到氮或pH胁迫时变化显著。2.菊苣水浸提液对4种牧草种子的种子发芽率、发芽指数、活力指数、幼苗根长及芽长生长主要表现为抑制作用，且随水浸提液浓度增加而抑制效应增强：同浓度下，高羊茅种子萌发受到的抑制效应最强。不同植物幼根和幼茎对水浸提液的敏感性不同；高羊茅的幼芽和幼根对菊苣根水浸提液极为敏感，在50g/L浓度下，高羊茅的幼芽和幼根抑制率为39.96％和38.83％。3.氮与pH等效耦合具有促进效应的矩形区域或点分别为：氮（149到168mg/L）pH（4.97到7.0）、氮（177mg/L）pH(6.33);而具有抑制效应的矩形区域或点分别为：氮（125到131mg/L）pH（6.71到6.88）、氮（180mg/L）pH（6.38）及氮（166mg/L）pH（7.59）。4.氮与pH的改变会影响到菊苣化感物质的分泌。不同浓度的氮及不同水平的pH处理后的菊苣根及茎提取液会影响到菊苣自身种子萌发及抗氧化酶的活性。5.菊苣根及叶水浸提液的总酚含量平均为1.04g/Kg，0.44g/1.04g/Kg，0.44g/KgKg。更多还原

【Abstract】 Biomass energy is a kind of high efficient and clean energy, which will become theimportant part of future energy. Chicory (Cichorium intybus) is a perennial Asteraceae energyplant accumulating energy in the form of inulin fructan, which not only has high feedingvalue, but also as an alternative energy source plants are concerned. The complexity anddiversity of chemical composition of Compositae plant are in the first, and they have a lot ofthe biochemical substances. Plant allelopathy in insecticidal, herbicidal, plant protection andecological restoration, has an important role. It can also explain the nature of interactionsbetween plants, but also for reasonable arrangement in planting grass and rotation provideimportant theoretical basis. Therefore, the allelopathic research has become a hot topic in theplant field of biological science. The experiment one was orthogonally designed toincorporate three factors at three levels using the L9(34) orthogonal matrix. It contained threedifferent target species (F. arundinacea, T. repens and M. sativa), three nitrogen treatments(0.5N,1N and2N) and three pH treatments (pH5.5，pH7and pH8.5). There were total of9treatments with three repetitions and comprised of27pots. Test determination contains twoparts. Test one under the treatment of nitrogen and pH interaction determined the donor plantcontent of chlorophyll and malondialdehyde (MDA); catalase (CAT), peroxidase (POD),superoxide dismutase (SOD) activity change；and the chloroplasts, MDA, soluble sugarcontent of receptor plant with the treatment of different concentrations of chicory osmoticliquid. Test two measured seed germination rate, germination potential, germination index,vigor index, root length and stem length of chicory, tall fescue, clover and alfalfa seedthrough the treatment of chicory extract. And leaf and root extract allelopathic substancecontent related were determined with liquid chromatography. Through those experiments, thequalitative and quantitative allelopathic activity of chicory was systematically studied.The received main results of experiments are as follows:1. Chlorophyll and MDA content were no significant change, but POD and SOD activityrose significantly with different nitrogen concentrations; chlorophyll but MDA content wassignificant change, and activity of POD and SOD rose significantly with different pH values;interaction of nitrogen and pH had significant effect on chicory growth; chlorophyll contentwere greatest with65.305mg/L N and pH5.5, and increased with N applied; MDA content were greatest with261.122mg/L N and pH5.5, and almost no chance when only N or pHstress; POD and SOD activity were highest with261.122mg/L N and pH8.5, and hadsignificant change when only N or pH stress.2. Aqueous extract of chicory root have certain influence on herb seed germination andgrowth of the seedling, namely, the inhibition of germination index, vigor index, seedlingroot and bud growth strengthened with an increase of aqueous extract concentration; seedgermination of festuca suffered the strongest inhibition effect with the same extractconcentration. Different plant seeding roots and stems have different sensitivity to aqueousextract; seeding root and stem of festuca is extraordinary sensitive to aqueous extract, whichinhibition rate reached39.96%and38.83%in50.0g/L extract concentration.3. The nitrogen supply and pH level were located at rectangular area defined by149to168mg/l nitrogen supply combining4.95to7.0pH value and point located at nitrogensupply177mg/l, pH6.33when they were in equivalent coupling effects; whereas theinhibitory effects of equivalent coupling nitrogen supply and pH level were located atrectangular area defined by125to131mg/l nitrogen supply combining6.71to6.88pH valueand two points respectively located at nitrogen supply180mg/l with pH6.38and nitrogensupply166mg/l with pH7.59.4. The chance of pH and nitrogen would affect allelochemical secretion of chicory.Aqueous extracts of chicory roots and leaf accompanied with treatment at different soil pHvalues and nitrogen concentrations influenced its germination, growth and the activity ofantioxidant enzyme.5. The phenolics contents of chicory root and leaf aqueous extracts were1.04g/Kg and0.44g/Kg on average, respectively.更多还原