南方红豆杉细胞培养中生产紫杉醇的研究进展

南方红豆杉是红豆杉科红豆杉属在中国的一个变种,是红豆杉属植物中紫杉醇含量较高的一种,但由于南方红豆杉野生资源稀少,故紫杉醇的产量有限,远不能满足市场对紫杉醇的需求。在红豆杉细胞培养中生产紫杉醇是未来相关研究的重要方向。综述了有关南方红豆杉愈伤组织诱导、细胞悬浮培养中生产紫杉醇的研究现状与研究进展,分析了南方红豆杉组织与细胞培养研究中存在的问题,并提出了可能解决的方法。     

红豆杉资源与紫杉醇研究进展

论述了国内外有关红豆杉资源与紫杉醇研究现状,并对红豆杉资源与存在问题,紫杉醇在植物中的分布、紫杉醇的研究历史、紫杉醇药理作用,红豆杉属植物中的化学成分,细胞与组织培养及紫杉醇开发应用等方面进行了综述。并且概述了红豆杉与紫杉醇研究的最新进展及今后的研究方向。     

南方红豆杉幼树生长动态观察

南方红豆村也叫美丽红豆杉（Taxuschinensis（Pilger）Rehdvar.maimei），广泛分布于我国南方及陕西、甘肃南部等省区，是一种良好的用材和绿化树种[1]。近些年来，由于从红豆杉属植物体中分离得到了紫杉醇（Taxol）等化合物，并证明其有显著的抗癌活性，因而引起国内外的普遍关注。然而，由于紫杉醇直接或间接地来源于红豆杉属植物体，而该植物生长缓慢，体内有效物质含量低，使得紫杉醇的供求矛盾异常突出‘”。目前认为能迅速、低成本地解决提取紫杉醇所需资源的有效途径是栽培红豆杉”’。因此，必须掌握红豆杉属植物的系统生长发育规…     

红豆杉属植物中紫杉烷类物质含量影响因素综述

紫杉烷是以抗癌药物紫杉醇为首的具有五甲基十五碳烯骨架的一类二萜类化合物的总称,多数为红豆杉属植物中的主要成分。其中有些紫杉烷可以作为半合成紫杉醇的原料,有些具有多方面的药理活性。从不同种源、不同性别及年龄、不同部位以及环境因子等方面对红豆杉属植物中紫杉烷类物质含量的影响因素进行概述,进而为人们对野生东北红豆杉资源合理、有效、充分的利用提供理论基础。不仅为紫杉醇大量生产提供解决途径,又可以避免野生资源遭到毁灭性的破坏。     

不同产地云南红豆杉紫杉醇的含量分析

本文用高效液相色谱仪分析了不同产地云南红豆杉树皮和鲜叶中的紫杉醇含量。云南红豆杉树皮中紫杉醇平均含量为０．００８１１％，含量与树木雌雄无关。在某个生长阶段中，紫杉醇含量随树木生长年龄增大而增加，靠近滇中地区云南红豆杉紫杉醇含量较滇西地区的为高，树皮中紫杉醇含量与鲜叶接近。     

不同产地云南红豆杉紫杉醇的含量分析

本文用高效液相色谱仪分析了不同产地云南红豆杉树皮和鲜叶中的紫杉醇含量。云南红豆杉树皮中紫杉醇平均含量为０．００８１１％，含量与树木雌雄无关。在某个生长阶段中，紫杉醇含量随树木生长年龄增大而增加。靠近滇中地区云南红豆杉紫杉醇含量较滇西地区的为高，树皮中紫杉醇含量与鲜叶接近。     

丽水“曼地亚”红豆杉非试管快繁技术

一、曼地亚红豆杉非试管快繁技术研究红豆杉属世界珍稀濒危植物,在世界各国分布很少,主要分布在加拿大、俄罗斯、印度、巴基斯坦和中国。以红豆杉植株为主要原料提取的紫杉醇,具有极好的抗癌作用。由于野生红豆杉生长周期长、资源少、远远不能满足紫杉醇生产的需求,鉴于红豆杉的药用价值和生态价值,国家已将红豆杉作为我国天然林保护工程,退     

紫杉醇药物的发展态势与云南省的红豆杉资源

综述了紫杉醇药物的发展史、市场的需求状况．并从6个方面研讨了获取紫杉醇的途径。指出通过规模化地人工种植红豆杉，扩展资源，制取紫杉醇，是当前发展紫杉醇药物生产的一条最有效的途径。此后，论述了云南省的红豆杉资源状况．以作为“云南红豆杉药用人工林营造技术试验示范”的立项背景。     

正交试验优选南方红豆杉外植体的消毒方案

南方红豆杉(Taxus chinensis var.mairer),又名美丽红豆杉,是红豆杉科红豆杉属红豆杉的一个变种.从其中提取出的紫杉醇是一种具有独特抗癌活性的二萜化合物,对卵巢癌,子宫癌,乳腺癌等多种癌症具有明显的治疗效果[1].然而该树种天然群体数量稀少,种子休眠期较长,生长十分缓慢,加之人为破坏,有濒临灭绝的危险,已被列为国家一级保护植物.利用组织培养的方法生产红豆杉提取紫杉醇,不仅可以保护野生资源,还能有效提高紫杉醇产率,具有良好的工业化前景.在组织培养过程中,污染是经常遇到的较难控制的问题.     

6个南方红豆杉种源苗期和幼龄生长差异

红豆杉是提纯抗癌药物紫杉醇的重要药用植物，因受制于红豆杉有限的野生资源，世界各国都在寻求多种方法生产紫杉醇，而通过红豆杉的人工栽培则是当今实行紫杉醇产业化的主要途径。南方红豆杉（Taxus chinensis var．mairei（Lemee et leve1．）Chang et L．K．Fu）为我国一级保护树种，材质优良、观赏价值高，相对于同属其它植物其紫杉醇含量虽然较低，但因其早期速生、宜短周期经营而开发价值较高。当前存在的技术瓶颈主要是药用优良新品种及配套高产栽培技术的缺乏。南方红豆杉广泛分布于长江流域、南岭山脉及河南、陕西、甘肃、台湾等省的山地或溪谷，种内变异丰富，但缺乏相关研究。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

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.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

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.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

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.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

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.     

CAD与建筑设计的关系

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。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

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.     

Risk Perception Among Non-industrial Private Forest Owners

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.     

Interactions in decomposition and N mineralization between tropical legume residue components

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.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

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.