克隆植物东方草莓对异质生境的适应对策

克隆植物被认为比非克隆植物更宜于利用异质性环境。在复杂的空间异质环境中，克隆植物可能形成了各种有效利用环境异质性的适应对策。对于克隆植物适应机制的研究，前人已做了大量的工作，特别是从形态和生物量分配等方面对简单异质生境下克隆植物的克隆整合和克隆分工进行了详细的研究。本研究以分布广泛的克隆植物东方草莓（Fragaria orientalis）作为研究对象，应用野外调查和实验生态学方法，采用多对比度单资源模型和不同向双资源模型，从形态和生理生态的角度，研究复杂异质生境下克隆植物的整合和分工及其耗益问题，分析不同类型的生境对克隆植物整合和分工的修饰作用，进而探讨克隆植物对异质生境的适应策略。克隆构型和分株种群特征是植物克隆生长及其生态适应对策研究的基本内容。本文通过野外调查，研究在不同光照条件下东方草莓克隆构型、分株种群特征以及点分布格局。结果表明：东方草莓的克隆构型随光照发生相应的变化，低光照下其匍匐茎节间长和分枝角度均增大而分枝强度减小；随光照减弱，东方草莓分株种群的生物量、根冠比和分株种群密度显著降低；不同光照下东方草莓分株均以随机分布为主但不同尺度下有所差异，其分布格局强度依次为旷地<林缘<林下。结合克隆植物对资源的利用对策，探讨了克隆构型和分株种群特征以及分布格局随环境条件变化的生态适应意义。不同生境斑块条件下克隆植物可能采取不同的适应对策。采用盆栽实验，研究不同水分对比度下克隆整合及其生理生态特征，并对单向和交互资源中东方草莓的克隆整合做了对比研究。结果显示：高的水分对比度能够促进东方草莓的克隆整合，并能刺激相连分株增加光合作用，东方草莓体内的氧化—抗氧化系统也II随对比度做出相应的反应。耗-益分析表明胁迫分株的受益是以供给分株的损耗为代价的，但从克隆片段总体来说是受益的。单向资源中东方草莓生长的绝对值高于交互资源，但耗-益分析表明生长于交互资源下东方草莓的克隆整合获益大于生长于单向资源下东方草莓的克隆整合获益。长期生长于特定生境的克隆植物，在进化过程中其克隆整合和克隆分工在对资源异质性的适应策略方面可能有所侧重。采用盆栽实验对来自不同海拔梯度的东方草莓的克隆整合和克隆分工对异质资源的适应对策进行了研究。实验结果表明，来自高海拔的东方草莓可塑性较差。来自两个海拔的东方草莓对切断匍匐茎的表现有所差异，总体上切断匍匐茎对来自高海拔的东方草莓影响更大些。另外，来自高海拔的东方草莓表现出更高的克隆分工。IIIClonal plants are known to be more suitable for the habitats of heterogeneousresources than nonclonal plants, perhaps due to their well developed adaptivestrategies to environmental heterogeneity. Many studies have been done on theadaptive mechanisms of clonal plants, especially on the clonal integration anddivision of labor with morphology and biomass allocation under simpleheterogeneous habitats. Based on field surveys, laboratory experiments, multi-contrastunidirectional resource model and reciprocal resource model, Fragaria orientalis, aRosaceae stoloniferous herb that widely distributes in China, was used to study thisplant’s morphological and physiological responses to complicated heterogeneoushabitats in terms of its clonal integration, division of labor and cost-benefit, as well astheir modifications by different habitats, so as to better understand the adaptivestrategies of clonal plants under heterogeneous environments.Clonal architecture and ramet population characteristics are of the major concernin the studies on growth and adaptive strategies of clonal plants. Clonal architecture,ramet population characteristics and spatial point pattern of F. orientalis underdifferent light intensity were studied with field observations. The results showed that,clonal architecture changed with light availability: Internode-lengths and branchangels of stolons were larger while branch intensities were smaller under lower lightintensity than those under higher light intensity; Biomass of ramet population,root-shoot ratio and density of ramet population decreased significantly with reduce oflight intensity; Under all light intensities, spatial pattern of ramets was mainlyrandomly distributed but it changed with different scales, with pattern intensity as:open space < forest edge < understory. Adaptation significance of the clonal architecture, the ramet population characteristics and the spatial pattern changing withdifferent environments was discussed according to these results.Clonal plants may take different adaptive strategies under different patches. Withpot culture, clonal integration and physiological parameters of F. orientalis underdifferent water contrasts were studied, and clonal integration under unilateralresources and reciprocal resources were also compared. The results suggested that,high water contrast improve the clonal integration of F. orientalis and increase thephotosynthesis of connected ramets. Oxidative and antioxidative system of F.orientalis also responded with changing water contrasts. According to cost-benefitanalysis, the drought-stressed ramets obtained benefits from the connectedwell-watered ramets, and as a whole, the clonal fragment could also get benefits.Growth of F. orientalis in homogeneous resources was better than that inheterogeneous resources, but the whole plant got more benefit through clonalintegration in heterogeneous resources than in homogeneous resources.Pot culture experiments were also used to study the adaptive strategies inutilizing heterogeneous resources by the plant populations from different altitudes.The results showed that, F. orientalis from alpine zones were shorter and lessexpanded with poorer clonal plasticity than those from middle mountains. F.orientalis from two different altitudes showed different responses to stolon severing,and as a whole, stolon severing had more influence on F. orientalis from alpine zones.In addition, F. orientalis from alpine zones exhibited higher division of labor, whichsuggested that clonal plants from different habitats develop their own adaptivemechanisms in their clonal integration and division of labor in response toenvironmental heterogeneity.

生姜化感作用机理及其栽培模式研究

近年来，随着对作物重茬（连年种植）障碍原因的深入研究，植物的化感作用越来越受到国内外众多学者的重视。而作为重要调料和药用植物的生姜，其连作障碍也备受关注，系统地研究生姜化感作用将有助于理解和最终解决生姜连作障碍问题。本文通过研究生姜不同部位、不同浓度的水浸液对与其间作的两个物种（大豆和四季葱）种子的萌发及幼苗生长的影响，从而证明生姜化感作用的存在；并通过温室盆栽实验研究了生姜的自毒作用（即研究生姜不同部位、不同浓度的水浸液对其幼苗的形态、生理生化、光合作用、土壤酶、土壤微生物多样性及土壤养分的影响），从而揭示生姜退化和衰老的机制，并为生姜筛选出合适的间作物种提供科学依据，对生姜连作障碍提出科学的解决方法。主要研究结果如下： 1. 与对照相比，生姜所有部位（根茎、茎、叶）、所有浓度（10、20、40、 80 g l-1）的水浸液均抑制了大豆种子和葱籽的萌发率、幼苗生长、水分吸收和脂肪酶活性，并且其抑制程度随着水浸液浓度的增加而增强，其生姜各部位水浸液抑制效应的强弱顺序为茎＞叶＞根茎。这一结果表明生姜根茎、茎、叶含有能够抑制大豆种子和葱籽种子萌发和幼苗生长的水溶性化感物质。根茎是生姜的主要收获部位，而生姜的残株（主要是茎和叶）应该从大田中处理掉以减轻其抑制效应。生姜水浸液中主要化感成分包括：根茎水浸液中主要是丁香酸和伞花内脂；茎水浸液中主要是阿魏酸，且其含量最高为73.4 ug/g；叶水浸液中除了阿魏酸，其他六种物质均检测出来，但含量较高的主要有丁香酸、伞花内脂和香豆酸。 2. 生姜茎和叶不同浓度的水浸液均显著抑制了生姜幼苗的株高、每株叶片数和叶面积，其抑制程度随着水浸液浓度的增加而有所增强，而生姜幼苗每株分枝数差异不显著；同时生姜水浸液也极大程度地影响了生姜幼苗的生物量（包括地下生物量、地上生物量和总生物量，均为鲜重）。在同一浓度下，茎水浸液对生姜幼苗形态指标及生物量指标均显示出最强的抑制作用，叶水浸液次之，根茎水浸液最弱。与对照相比，低浓度的生姜根茎水浸液提高了生姜幼苗叶片内四种抗氧化酶（SOD、POD、CAT、APX）活性，高浓度的根茎水浸液抑制了四种抗氧化酶活性，而茎和叶水浸液均随着浓度的增加而抑制了四种抗氧化酶活性，三种水浸液均随着浓度的增加降低了生姜幼苗叶片内叶绿素的含量，而增加了生姜幼苗叶片的相对电导率和丙二醛含量。同时，三种水浸液均随着浓度的增加降低了生姜幼苗的光合参数（包括胞间CO2浓度、气孔导度、蒸腾速率及净光合速率）。 3. 三种生姜水浸液对所测六种土壤酶活性均产生了不同程度的影响，其中影响最大的是酸性磷酸酶和蔗糖酶，在10 g l-1 时就达到了显著水平，并且所有酶均有随着水浸液浓度增加而增大的趋势；相同部位的水浸液随着浓度的增加，细菌和真菌的数量呈增加趋势，而放线菌的数量呈减少趋势；三种生姜水浸液均随着浓度的增加降低了土壤中有机质的含量，加剧了土壤中硝态氮含量的积累，根茎水浸液对土壤有效磷、速效钾和铵态氮均显示出低浓度提高其含量而高浓度降低其含量的趋势，而茎和叶水浸液则随着浓度的增加均降低了其含量。 4. 与生姜单作相比，所有间作系统均在旺盛生长期和收获期不同程度地提高了土壤酶活性，同时也增加了土壤细菌数量及土壤微生物总数但不显著；所有间作系统在旺盛生长期和收获期均不同程度地影响了土壤真菌及放线菌数量（增加或减少），所有间作系统间的多样性指数差异不显著，除了旺盛生长期四种作物（生姜-大豆-四季葱-大蒜）的间作模式显著降低了多样性指数，其值仅为生姜单作的33.18%；生姜与大豆间作不仅提高了19.6%的生姜产量而且获得了较好的经济效益，并且，所有间作系统均显著抑制了生姜姜瘟病的发生。 5. 不同栽培模式不同程度地影响了收获期生姜的株高、分枝数、根茎产量及内在品质。其中处理2显著地促进了生姜的分枝（10.5%），同时处理2、3和4也促进了生姜的生长（株高分别增加了15.0%、11.4%和14.0%），并且这三个处理提高了生姜的产量；处理2和3能有效提高生姜块茎中维生素C（分别较单作生姜显著提高了3.29%和4.05%）、处理3显著提高了可溶性糖（8.2%）、姜辣素（4.6%）和蛋白质等有益物质的含量，降低硝酸盐有害物质的含量（处理2显著降低了14.0%），改善了姜块的外观和内在品质。并且，生姜与大豆间作具有最高的纯收入和产投比，分别较生姜单作提高了24.80%和8.8%。Recently, allelopathy has been more and more paid attentions by national and foreign scholars with profound research on reasons of crop replanted (continuous planted) obstacle. Ginger rhizome is valuable all over the world either as a spice or herbal medicine and ginger replanted obstacle is also paid attentions. Systematic research on ginger allelopathy will contribute to understanding and ultimate solving problem of ginger replanted obstacle. The effects of ginger aqueous extracts with different parts and concentrations on seed germination and early seedling growth of soybean and chive were studied in this article to testify that ginger existed allelopathy. Furthermore, ginger autotoxicity was also studied by pot experiment in greenhouse (namely research on effects of ginger aqueous extracts with different parts and concentrations on morphological indexes, physiological and biochemical indexes, photosynthesis, soil enzymes, soil microbial diversity and soil nutrients) to reveal mechanism of ginger degeneration and senescence, provide scientific basis for selecting appropriate intercropping species and put forward scientific resolvent for ginger replanted obstacle. The main results were as follows: 1. All aqueous extracts at all concentrations inhibited seed germination, seedling growth, water uptake and lipase activity of soybean and chive compared with the control, and the degree of inhibition increased with the incremental extracts concentration. The degree of toxicity of different ginger plant parts can be classified in order of decreasing inhibition as stem＞leaf＞rhizome. The results of this study suggested that rhizome, stem and leaf of ginger contained water soluble allelochemicals which could inhibit seed germination and seedling growth of soybean and chive. The rhizome is the main harvested part of ginger. The residue (mainly stems and leaves) of the ginger plant should be removed from the field so as to diminish its inhibitory effect. The main allelopathic components of three kind of aqueous extracts were as follows: Rhizome extract chiefly contained syringic acid and vmbelliferone and stem extract mainly contained frulic acid whose content was the highest (73.4 ug/g). The other six substances were detected except of frulic acid, but only contents of syringic acid, vmbelliferone and p-coumaric acid were higher. 2. Stem and leaf aqueous extracts of ginger with different concentrations significantly inhibited plant height, leaf numbers per plant and leaf area, and the degree of inhibition increased with the incremental extracts concentration. However, tiller number per plant of ginger seedling showed no significant difference. At the same time, ginger aqueous extracts also influenced biomass including under-ground biomass, above-ground biomass and total biomass (fresh weight) to a large extent. Under the same concentration, stem aqueous extract showed the mostly inhibitory effect on morphological indexes and biomass indexes of ginger seedling. Rhizome aqueous extract showed the leastly inhibitory effect and leaf aqueous extract was intervenient. Enhanced concentration of ginger aqueous extracts significantly reduced total chlorophyll content, accompanying with increases in memberane permeability (REL) and lipid peroxidation (MDA). Compared with the control, rhizome ginger aqueous extract of lower concentration (10 g l-1) increased the activities of major antioxidant enzymes (superoxide dismutase, SOD; peroxidase, POD; catalase, CAT; ascorbate peroxidase, APX) of ginger leaf tissue and higher concentration inhibited the activities of four antioxidant enzymes. However, stem and leaf aqueous extract inhibited the activities of four antioxidant enzymes with increase in concentration. Meanwhile, enhanced concentration of ginger aqueous extracts significantly reduced photo-parameters of ginger seedling (including CO2 concentration, stoma conductivity, net photosynthesis rate and transpiration rate). 3. Rhizome, stem and leaf ginger aqueous extract showed different effect on six soil enzyme activities, and acid phosphatase and invertase showed significant effect when aqueous extract concentration got 10 g l-1. Furthermore, six soil enzyme activities increased with increase in aqueous extract concentration. Bcterial and fungi number tended to increase while antinomyces tented to decrease with the increase in aqueous extract concentration of identical part. Ginger aqueous extracts reduced soil organic matter content with increased concentration, accompanying with NO3-—N accumulation in soil. Rhizome aqueous extract showed the same tendency for available P, available K and NH4+—N, namely lower concentration increased their contents in soil and higher concentration reduced their contents. While stem and leaf aqueous extracts reduced their contents with the increamental concentration. 4. All intercropping systems increased soil enzyme activities to different extent both at VGS and at HS compared to solo ginger. All intercropping systems increased the colony numbers of soil bacteria and total of soil microbe but not significantly either at VGS or at HS. All intercropping systems increased the colony numbers of soil fungi and actinomytes to a different extent (increase or decrease) both at VGS and at HS. For DI, difference between all cultivation patterns and S-G was not significant either at VGS or at HS except that G-S-C-G whose value was only 33.18% of S-G at VGS significantly decreased. G-S not only increased ginger yield by 19.6% but also obtained better economic benefit. Furthermore, all intercropping systems significantly inhibited occurrence of bacterial wilt of ginger. 5. Different cultivated pattern influenced plant height, tiller numbers, rhizome yields and intrinsic quality of ginger. Treatment 2 significantly facilitated tiller occurring (10.5%). Treatment 2, 3 and 4 promoted ginger growth (plant height respectively increased 15.0%、11.4% and 14.0%) and enhanced rhizome yields. Treatment 2 and 3 effectively increased vitamin C content (significantly increased 3.29% and 4.05% compared to solo ginger). Treatment 3 significantly increased contents of beneficial substances such as soluble sugar (8.2%), gingerols (4.6%) and protein. Treatment 2 significantly decreased contents of deleterious substance namely nitrate (14.0%) and improved appearance and intrinsic quality of ginger rhizome. Furthermore, treatment 2 (ginger/soybean intercropping) could obtain better economic benefit and showed the highest net income and ratio of benefit and cost whose values respectively increased by 24.80% and 8.8% compared to solo ginger.

Characteristics of indoor/outdoor PM2.5 and elemental components in generic urban；roadside and industrial plant areas of Guangzhou City；China

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Compound specific D/H ratios and molecular distributions of higher plant leaf waxes as novel pale oenvironmental indicators in the Chinese Loess Plateau

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