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银杏叶萜内酯资源和生长规律初探 总被引：4，自引：0，他引：4
介绍我国银杏的资源分布和品种。用ＨＰＬＣ－ＲＩ对各地银杏叶的萜内酯含量进行初步调查，结果表明３－５年幼苗的叶萜内酯含量明显高于老树叶。同时对幼苗叶中萜内酯的生物生长规律进行研究，表明在９月底１０月初萜内酯富集达到最高。 相似文献
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干旱胁迫对银杏叶萜内酯年动态变化的影响 总被引：1，自引：0，他引：1
以2年生盆栽实生苗为研究材料,通过人工模拟干旱胁迫环境,探索4水平干旱胁迫(土壤含水量分别为田间持水量的75％ ～ 80％、55％ ～ 60％、40％ ～45％和30％～35％)对银杏叶萜内酯类物质季节变化的影响.结果表明:干旱胁迫下,生长季节不同,银杏叶内白果内酯BB、银杏内酯GC、GA、GB及总萜内酯含量变化具有显著差异,随着生长季节的变化银杏叶萜内酯类物质含量变化呈“先升高后降低”的趋势.适度干旱条件下可以促进银杏萜内酯类物质的合成,尤其轻度和中度干旱条件下,萜内酯含量比适宜水分条件下明显增多.考虑到叶产量、叶萜内酯美物质含量以及采叶与采时的关系等,在实际生产中可以考虑在植物生长初期,给予银杏苗正常的水分供应以获得最大的生物产量,在6-10月份叶片发育完全后适当进行轻度干旱处理(土壤水分含量为田间持水量的55％ ～60％)收获叶片,可获得最大的萜内酯单株有效经济产量. 相似文献
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银杏不同类型枝条叶片萜内酯含量年周期变化规律 总被引：2，自引：0，他引：2
为了了解不同时期银杏不同枝型叶片萜内酯的含量,采用气相色谱法对银杏雄叶丛枝、雌叶丛枝、雄长枝、雌长枝和雌短枝银杏叶萜内酯含量的年周期变化进行了测定。结果表明:不同枝型按照银杏叶的总萜内酯含量由大到小排列依次为:雄叶丛枝、雌长枝、雌叶丛枝、雄长枝、雌短枝,除雌短枝外,其它枝型总萜内酯含量均在9月初达到1年中的最大值;GA是所测4种萜内酯中含量最丰富的,不同枝型按照GA含量由大到小排列依次为:雄叶丛枝、雄长枝、雌叶丛枝、雌长枝、雌短枝,除雌短枝GA含量在10月初到达含量的高峰外,其它均在9月初达到高峰;GB、GC和BB含量低,变化规律较一致,落叶前含量基本稳定。 相似文献
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银杏叶用园建园材料选择的研究 总被引：2，自引：0，他引：2
对来自浙江、河南、山东、江苏等银杏产地的１３个优良单株３年生银杏嫁接苗的叶产量、黄酮含量、黄酮的组成成份、内酯含量、内酯的组成成份及黄酮、内酯的年变化规律等进行了比较研究。结果表明,不同银杏优良单株间的叶产量、黄酮含量、内酸含量等存在显著差异;黄酮和内酯在叶中的含量以９￣１０月最高,银杏植株各器官中黄酮的含量以叶最高,茎最低;在总黄酮中,槲皮素所占比例最大,其次为山奈酚,最后为异鼠李素;内酯的组成成分中则以银杏内酯Ａ为最大,其次为白果内酯,最后为银杏内酯Ｂ、银枵内酯Ｃ;根据叶产量、黄酮产量、内酯产量等指标,将１３个银杏叶用优良单株分成３类：优－Ｅ４,中等－Ｅ１、Ｅ２、Ｅ５、Ｅ６,差－Ｅ３、Ｅ７、Ｅ８、Ｅ１０、Ｗ２、Ｗ３、Ｗ４、Ｗ５,即优良单株Ｅ４是采叶园最后的建园材料,Ｅ１、Ｅ２、Ｅ５、Ｅ６等次之。 相似文献
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【目的】筛选银杏优良叶用家系。【方法】以38个银杏半同胞家系叶片为研究对象,测定其主要功能性状（单叶干质量、单叶面积、比叶干质量）和主要功能组分（总黄酮、萜内酯、聚戊烯醇）的含量,采用主成分分析的隶属函数法综合评价38个银杏家系的叶品质,并基于叶用价值对这些家系进行聚类。【结果】不同银杏半同胞家系间叶功能性状及组分含量均存在极显著差异（P <0.01）,呈现出较高的遗传变异,变异系数为7.5%～36.3%。叶主要功能性状中单叶干质量与单叶面积、比叶干质量均呈现极显著正相关（P <0.01）;叶主要功能成分总黄酮、萜内酯、聚戊烯醇的含量间均无显著相关性（P> 0.05）;主要功能组分仅有萜内酯含量与单叶干质量、单叶面积、比叶干质量呈现极显著正相关（P <0.01）。基于主成分分析的隶属函数综合评价与聚类分析结果,筛选出较优的8个家系,表现为比叶干质量（或单叶干质量）和功能性组分含量较优。其中：18号家系的比叶干质量、叶片总黄酮含量和叶片萜内酯含量最高;16、30、34、36、39、54、65号家系单叶干质量和单叶面积最大,比叶干质量、萜内酯含量中等偏上。【结论】可... 相似文献
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银杏树龄,性别,繁殖,采叶期对叶片中黄酮,内酯含量的影响 总被引：7，自引：0，他引：7
为了解银杏叶片中黄酮及内酯含量以及其变化规律对叶用园的建立、管理、对EBG提取，我们对贵州部分地区银杏树龄、性别、繁殖方式及采叶期对银杏叶片黄酮、内酯含量的影响进行了研究，为银杏叶的合理利用提供依据。1材料与方法供试的银杏叶片，于1995～1996年分别采自贵州农学院银杏种质资源圃、贵州市尖山村、惠水县摆金村、遵义县兴林银杏研究所、正安县、务川县、道真县及遵义地区农科所银杏园。银杏叶于9月上旬采收后烘干或凉干。供不同采叶期黄酮、内酯分析的叶片干6～11月，每月中旬采样。银杏黄酮：叶样粉碎后，用酸水解，进LG—3… 相似文献
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对不同修剪方式的银杏进行了叶片内黄酮和内酯类物质含量测定,结果发现,修剪对银杏黄酮和内酯类物质的含量具有显著的影响,经修剪的银杏其叶片内的银杏黄酮和内酯含量均显著增加,两类物质含量的变化具有相同的规律,其中矮化修剪对银杏黄酮和内酯类物质含量影响最大,分别比没有修剪的银杏高28．2％和20．1％;整形修剪对银杏黄酮和内酯类物质含量影响最小,分别比没有修剪的银杏高3．8％和1．96％。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
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本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):131-138
The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):472-479
Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken. 相似文献
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Srisuda Thippayarugs Banyong Toomsan Patma Vityakon Viriya Limpinuntana Aran Patanothai Georg Cadisch 《Agroforestry Systems》2008,72(2):137-148
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic
or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts
(stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea
(Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content
as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest
N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized
to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea,
largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for
N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant
components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N
released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures
were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality
components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in
the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols.
Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest
age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its
components are mixed. 相似文献
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A. Rigueiro-Rodríguez M. R. Mosquera-Losada E. Gatica-Trabanini 《Agroforestry Systems》2000,48(3):245-256
The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste
disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization,
(2) milk sewage sludge at 40 kg N ha−1 target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two
pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha−1. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1); (2) Lolium perenne L. var. Tove (25 kg ha−1) + Trifolium repens L. group Ladino (4 kg ha−1) + Trifolium pratense L. var. Marino (1 kg ha−1). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea
(Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m2, with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect
on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage
sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but
affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral
systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献