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综述了生物活性物质熊果酸的植物资源概况、种类分布和分布差异性.熊果酸在植物中分布很广,其中熊果酸含量较高的植物有:希腊鼠尾草、夹竹桃、迷迭香、西班牙鼠尾草、长春花、六座大山荆芥、小冠薰、长穗薰表草、百里香、苦丁茶、冬季香薄荷、枇杷、枸骨、白花蛇舌草和樱桃肉桂,分别选74.50、43.00、41.00、40.20、37.00、29 20、20 20、19.00、18.80、17.70、16.00、12.30、10.60、10.07和10.00 mg/g.熊果酸主要分布于茶树、果树、药用植物、香草植物及泡桐等其它植物中,熊果酸的分布还存在着品种差异性、植物部位差异性、区域差异性、季节差异性和生长条件差异性等.对熊果酸植物资源分布状况的充分了解,可为生物活性物质熊果酸的可持续研究开发、高值化和规模化利用提供物质基础. 相似文献
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百里香属植物资源的综合开发利用 总被引：10，自引：0，他引：10
百里香属植物资源的综合开发利用杨鸿佑，杨奇志（辽宁省农业区划研究所１１００３４）（辽宁大学）１百里香属的形态特征及本省分布百里香属（ＴｈｙｍｕｓＬ。）植物，呈小灌木状，具匍匐茎和发育茎，根系发达。自然生长成为优势群落状态，密布地表的特点。植株高仅５～... 相似文献
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Several extracts of Origanum dictamnus, an endemic plant of Greece growing only in the island of Crete and the bioassay-directed isolated ursolic acid, were tested in vitro against the P388 (murine leukemia) and the human bronchial epidermoid cancer NSCLC-N6 (non small cell lung cancer) cell lines. Both the initial dichloromethane extract and the isolated from it ursolic acid exhibited cytotoxic activity. Ursolic acid was also tested in vivo, on murine ascite leukemia P388, where it exhibited at a dose of 50 mg/kg a marginal antileukemic activity. 相似文献
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Valladares F Arrieta S Aranda I Lorenzo D Sánchez-Gómez D Tena D Suárez F Alberto Pardos J 《Tree physiology》2005,25(8):1041-1052
Shade tolerance, plastic phenotypic response to light and sensitivity to photoinhibition were studied in holly (Ilex aquifolium L.) seedlings transported from the field to a greenhouse and in adult trees in the field. All plants were growing in, or originated from, continental Mediterranean sites in central Spain. Seedlings tolerated moderate but not deep shade. Mortality was high and growth reduced in 1% sunlight. Survival was maximal in 12% sunlight and minimal in full sunlight, although the relative growth rate of the seedlings surviving in high light was similar to that of plants in moderate shade. Maximum photochemical efficiency at predawn was significantly lower in sun plants than in shade plants in the field, revealing chronic photoinhibition that was most pronounced in winter. Plasticity in response to available light varied according to the variable studied, being low for photosynthetic capacity and stomatal conductance, and high for specific leaf area, root:shoot ratio and leaf area ratio, particularly in seedlings. Differences in water relations and hydraulic features between sun and shade plants in the field were marginal. High water potential at the turgor loss point of field-grown plants suggested that holly is sensitive to drought during both the seedling and the adult stage. Low relative growth rates in both high and low light with low physiological plasticity in response to light indicate the existence of a stress-tolerance mechanism. We conclude that holly is a facultative understory plant in areas of oceanic and relatively mild climate, but an obligate understory plant in dry continental areas such as the study site. The impact of abandonment of traditional management practices and climate change on these Mediterranean populations is discussed. 相似文献
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Ozone pollution was analyzed in arolla pine (Pinus cembra L.) forests growing over two mountain ranges located in southern France by using specific ozone-sensitive tobacco plants as bio-indicators and a physico-chemical analyzer. Concentrations of abscisic acid (ABA) were determined in needles of healthy and declining trees in a massif with a declining forest and in a massif with a healthier forest. In addition, ABA was quantified in needles of trees exposed to either charcoal-filtered air or unfiltered air supplemented with ozone in open-top chambers located at the Col du Donon. The concentration of ABA in needles of injured trees increased when the trees were exposed to ozone either under field conditions or in open-top chambers; however, the difference in ABA concentration between control and ozone-exposed needles was less in the open-top chambers, where ozone was the sole variable, than in the field. The results are discussed in the context of the effects of ozone on plant water relations and hormone-mediated cell defense. 相似文献
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植物蛋白酶抑制剂及其在林木抗虫基因工程中的应用 总被引：8，自引：0，他引：8
植物蛋白酶抑制剂是除Bt之外又一个愈来愈研究较多的抗虫基因资源,其分布广泛,在豆科、茄科、禾本科、葫芦科及十字花科等植物中存在较多。植物蛋白酶抑制剂抗虫基因主要通过2种途径获得并在多种植物中进行转化,获得抗虫转基因植株。植物蛋白酶抑制剂在林木抗虫基因工程中的应用刚刚起步。本文在总结我国林木病虫害防治现状的基础上,阐述植物蛋白酶抑制剂在林木抗虫基因工程中的应用前景,同时也探讨植物蛋白酶抑制剂在林木害虫防治应用中存在的问题及解决途径。 相似文献
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通过实地调查、样地分析,对云霄县的木本植物资源开展了调查.结果表明:云霄县境内有木本植物114科378属832种,其中野生木本植物有89科260属601种,栽培的木本植物73科173属277种,优势科为蔷薇科、茜草科、豆科等26科,优势属为以悬钩子属、冬青属、榕属等41属.乔木315种、灌木364种、木质藤本128种、... 相似文献
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园林绿化中植物配置的多样性问题 总被引：1，自引：0，他引：1
对园林绿化植物配置中存在的多样性问题进行了论述,从增加绿化植物种类,加强彩叶树种、开花树种、抗性树种以及攀缘植物和地被植物的应用等方面总结了园林植物配置中应当注意的问题,并进一步分析了园林绿化中丰富植物品种的途径。 相似文献
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In spring, nitrogen (N) uptake by apple roots begins about 3 weeks after bud break. We used 1-year-old 'Fuji' Malus domestica Borkh on M26 bare-root apple trees to determine whether the onset of N uptake in spring is dependent solely on the growth stage of the plant or is a function of soil temperature. Five times during early season growth, N uptake and total amino acid concentration were measured in trees growing at aboveground day/night temperatures of 23/15 degrees C and belowground temperatures of 8, 12, 16 or 20 degrees C. We used (15NH4)(15NO3) to measure total N uptake and rate of uptake and found that both were significantly influenced by both soil temperature and plant growth stage. Rate of uptake of 15N increased with increasing soil temperature and changed with plant growth stage. Before bud break, 15N was not detected in trees growing in the 8 degrees C soil treatment, whereas 15N uptake increased with increasing soil temperatures between 12 and 20 degrees C. Ten days after bud break, 15N was still not detected in trees growing in the 8 degrees C soil treatment, although total 15N uptake and uptake rate continued to increase with increasing soil temperatures between 12 and 20 degrees C. Twenty-one days after bud break, trees in all temperature treatments were able to acquire 15N from the soil, although the amount of uptake increased with increasing soil temperature. Distribution of 15N in trees changed as plants grew. Most of the 15N absorbed by trees before bud break (approximately 5% of 15N supplied per tree) remained in the roots. Forty-six days after bud break, approximately one-third of the 15N absorbed by the trees in the 12-20 degrees C soil temperature treatments remained in the roots, whereas the shank, stem and new growth contained about two-thirds of the 15N taken up by the roots. Total amino acid concentration and distribution of amino acids in trees changed with plant growth stage, but only the amino acid concentration in new growth and roots was affected by soil temperature. We conclude that a combination of low soil temperature and plant developmental stage influences the ability of apple trees to take up and use N from the soil in the spring. Thus, early fertilizer application in the spring when soil temperatures are low or when the aboveground portion of the tree is not actively growing may be ineffective in promoting N uptake. 相似文献