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紫檀属树种在我国的引种概况及发展前景 总被引：4，自引：0，他引：4
对我国引种栽培的紫檀属树种进行了系统调查，结果表明：我国已引入紫檀属8个树种，其中有6个种生长比较好，能正常开花结实。紫檀属树种引种于我国热带、南亚热带地区的红壤、砖红壤、沿海冲积土和沙壤上，大多数表现出较强的适应性，生长良好，能耐0℃以上的短暂低温，抗10级以下台风；而且生长迅速，在良好栽培条件下，中幼龄林木年均胸径生长量可达2cm以上。紫檀属树种开始形成心材的年龄因树种而异，檀香紫檀、印度紫檀为15～20年，古巴紫檀为7年，马拉巴紫檀为4年。紫檀属树种作为特类珍贵用材树种和园林绿化树种，在我国具有广阔的发展前景，建议各级政府立项开展种质资源的系统引进以及相关研究与推广工作。 相似文献
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檀香紫檀是世界著名顶级红木树种之一,其心材主要应用于高档家具、乐器、细木工及雕刻制作,其心材、树皮和种子的提取物具抗糖尿病、抗癌、护肝等功效,药用价值极高。我国20世纪50年代末即开始引种檀香紫檀,然而一直未得以规模种植,种苗短缺是当前制约我国檀香紫檀人工林发展的首要问题。以印度紫檀或大果紫檀大树作为砧木,经过多年的试验研究,解决了檀香紫檀嫁接采种园营建的关键技术问题,并利用15个初选优树材料营建了嫁接采种园,为檀香紫檀采种园规模发展及优良种质材料的推广应用提供技术基础。文中简要介绍了檀香紫檀嫁接采种园的营建技术,并对15个无性系的生长差异进行了对比分析。结果表明:15个檀香紫檀无性系的平均主枝长、主枝直径及最大主枝长、主枝直径间差异均显著(P0.05),其分枝数差异不显著(P≥0.05);整体而言,15和12号无性系的表现均最佳,其次为6、9和10号无性系;以印度紫檀为砧木的嫁接效果优于大果紫檀砧木,两者间平均主枝长和主枝直径的差异均显著,这与印度紫檀相对于大果紫檀而言对土壤的适应性更强、生长更快有关。 相似文献
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云南热区印度紫檀容器育苗基质选择 总被引：1，自引：0，他引：1
为选择出珍贵红木树种印度紫檀在云南热区适宜的容器育苗基质,以咖啡壳、蔗渣、牛粪、火烧土及森林土等当地易于取得的材料为试验对象,配制成6种不同的育苗基质,开展了不同育苗基质对印度紫檀容器苗各生长指标影响的研究。结果表明:不同育苗基质对印度紫檀幼苗的苗高、地径、叶片数量、根系生长以及鲜质量积累等指标均有显著影响,咖啡壳+牛粪基质培育的苗木表现最好,平均苗高、地径、叶片数量、主根长、单株鲜质量比传统纯森林土基质分别高138.46%,44.86%,272.48%,94.91%和557.42%,是较为理想的育苗基质,可用其取代传统的纯森林土基质,在云南热区印度紫檀苗木生产中推广应用。 相似文献
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在孟加拉西部的Pundibari地区,研究在4个采集（豆荚）时间,3个采集豆荚长度（〈10cm,10-20cm和〉20cm）,以及进行的13种预处理对大叶合欢种苗生长和萌发率的影响。豆荚采集时间为2月19日,且没有任何预处理,大叶合欢种子萌发率为92.5%。这明确表明,在2月19日采集的种子具有非休眠,有活力和生理成熟的特性。从长度为10-20 cm豆荚剥离出的种子,2月19日播种,种苗生长良好。利用硫脲预处理种子后,种子的萌发率并没有表现出明显提高,但是当利用低浓度硫脲（100 μL·L-1）预处理种子后,有利于种苗生长。 相似文献
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The efficiency of the botanical insecticide (BI) NeemAzal T/S (containing 1% Azadirachtin A), on the basis of azadirachtin
applied in a dose of 20 g a.i. ha−1 against Brassica pod midge (Dasineura brassicae), has been monitored for 4 years. The biological efficiency of BI was compared with the efficiency of some synthetic insecticides.
It was ascertained that BI was very efficient in decreasing the number of damaged oilseed rape pods (ranging from 56.5 to
85.9% compared to untreated plants) and its efficiency was comparable with synthetic insecticides based on Chloronicotinyl
(Thiacloprid) and Neonicotinoid (Acetamiprid). BI’s efficiency was, in some years, even significantly higher compared to pyrethroid
(λ-cyhalothrin). The high biological efficiency of azadirachtin that we ascertained was significantly reflected in increasing
potential crop yields. The yield increase of azadirachtin ranged between 9.3 and 19.4% compared to the control sample. Azadirachtin
showed the highest yield for the whole time of experimentation, and in some years the yield increase was significantly higher
compared to some synthetic agents. 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