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Micropropagation has the potential to provide very high multiplication rates of selected tree genotypes, with resulting short-term silvicultural gains. Aseptic cultures have been established from seeds, seedlings, shoots, flowers and lignotubers. Callus cultures have been established from a wide range of tissue sources for at least 30 species of Eucalyptus. Plant regeneration from callus was successful for 12 of these species. Micropropagation through axillary proliferation, or adventitious shoot proliferation on nodal explants, or both, has been successful. An agar-based medium of Murashige and Skoog with a low auxin/cytokinin ratio is most commonly used for shoot multiplication. Vitrification and shoot senescence remain problems. Gibberellic acid was added in some media to stimulate shoot elongation. Various media are used for in vitro root initiation. Suspension and protoplast cultures have been achieved and plants have been regenerated from protoplasts. In vitro techniques are presently being applied to Eucalyptus to achieve genetic transformations. 相似文献
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通过 5年的调查研究 ,收集大量不同立地、不同年龄、不同经营类型的实测资料 ,总结了国内外经营湿地松的各种经验 ;从立地分类与评价、良种培育、森林生长类型等方面进行研究 ,提出了几种重要湿地松经营模式的系统经营技术 ,并以经营数表的形式表现出来 ,且对湿地松的综合利用、松香的深加工进行了专门研究 . 相似文献
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Dr. E. Naton 《Journal of pest science》1978,51(9):136-139
50 pesticides have been tested for side effects against the beneficial insectPhygadeuon trichops Thomson (Ichneumonidae) using a living plant method. In this connection on the one hand among the insecticides compounds could have been found, which are harmless to this insect and therefore suitable for employment in programs for integrated pest control, on the other hand compounds have been found among the herbicides and fungicides harming these beneficial insects. These results are compared with findings obtained bt the method using glass cages. For about the half of the comparable instances the tests in the glass cages turned out to be to hard, that means the compounds are acting more harmfull than during the test on living plants. 相似文献
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Die Fraßtätigkeit von Dermestidenlarven (Dermestes peruvianus Castelnau) in verschiedenen Baustoffen
Ch. Künast 《Journal of pest science》1978,51(9):134-136
20 trials of materials used in buildings have been offered to dermestid larvae to bore in for pupations. Two different types of damage are described. Eight different test substances have been more or less damaged by the larvae. 相似文献
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Chronic obstructive pulmonary disease (COPD) is a major global health problem. The current therapies are inadequate and have numerous adverse effects. There is an acute need of potential alternative therapies. Medicinal plants are classical and most widespread form of medication for treating various human ailments throughout the world. For COPD also, various plants are practiced in many countries. We have surveyed the literatures for the medicinal plants which are used in obstructive lung diseases such as bronchitis and emphysema. These plants were segregated into two categories. Firstly, the plants which are used for obstructive lung diseases based on various traditional recommendations only. Secondly, the plants or their formulations which have been studied grossly in COPD patients and animal models for their scientific validation. Further, we have described some known cellular and molecular factors involved in COPD and their modulation by plant-derived compounds. Certain future perspectives have also been discussed. 相似文献
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森工企业原木产品物流管理的研究 总被引:1,自引:0,他引:1
本文分析了森工企业商品林原木产品采伐阶段、运输阶段、销售阶段物流管理特点以及影响森工企业原木产品物流的主要因素及存在的问题,提出了森工企业原木产品物流管理的对策。 相似文献
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国外针叶树种间杂交研究进展 总被引:9,自引:0,他引:9
杂种在工业用材林中的作用越来越受到世界各国重视。数十年来不少国家都开展过广泛的针叶树种间杂交研究,为选出各自适用的种间杂种,在理论、方法和实用性方面取得重大进展。通过种间杂交创造新的、对特殊生境更有适应力的杂种对引入树种更有效果。若干外域树种引入我国后表现良好,并成为主要造林树种,探索它们的杂种利用,对开展边沿低质土地的造林有重大实用性。通过推行“杂种林业”,提高我国工业人工林的经营效益,今后将成为遗传改良的一个重要领域。本文概述世界一些国家在这一领域的经验,供实施中借鉴。 相似文献
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调查近2~4年常德引种的16个杨树品种造林生长和抗逆性情况,以及不同立地条件、培管措施等因素对杨树品种生长的影响,从中筛选出适应当地发展的杨树品种,并对杨树造林提出建议。 相似文献
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2004~2012年,勐腊子保护区内共有31个村寨受到亚洲象不同程度的为害,其中仅1年受到为害的有16个村寨,占总为害村数的51.6%,受到6年以上为害的有5个村寨,占16.1%。亚洲象的为害与村寨的分布密度有一定的关系,村寨分布密度大的区域亚洲象为害相对较小,分布密度小的区域为害较大。稻谷、玉米、甘蔗和香蕉等作物是亚洲象喜食的食物,是亚洲象的主要为害对象。亚洲象虽然不直接取食橡胶、辣椒等植物,但其在活动过程中由于踩踏等原因也造成了这些植物大量损失。为了有效缓解亚洲象的为害,提出做好栖息地的保护与恢复、促进产业结构调整和建立预警预报系统等建议。 相似文献
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拉市海国际重要湿地是我国重要的候鸟越冬栖息地之一,针对其整体环境整治问题,地方政府和管理部门做了大量工作,取得了较好成效,但还存在退化沼泽湿地急需修复、退养鱼塘急需生态修复、入湖河道急需治理等问题,基于此,提出退化沼泽湿地、退塘还湿、入湖河段生态修复以及破碎化湖滨带治理、外来物种防控等生态修复方案。通过湿地生态修复,湿地整体生态环境得到改善,候鸟栖息地、食源地得到修复,湿地植被和生物多样性明显增加,湿地景观得到优化,湿地生态服务功能有所提高。 相似文献
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本文总结了太行山区过去几十年林业生产的教训,把近几年的“生态经济沟”经验,应用到太行山南部低海拔岗坡地形区的开发治理中,提出了建设“生态经济岗”的设想及盘龙岗试点的规划方案。 相似文献
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"三北"地区国外灌木树种引进 总被引:2,自引:0,他引:2
1998—2002年共引进国外灌木种批76个、58种,其中41个种在青海天然分布区之外,为首次引进新属、新种或新品种。将引进种批经催芽处理后,分别按引进年度进行春播或秋播。共有54个种批出苗,占总引进种批的78.9%。分别在理水渡域的西宁和黄河流域的循化两地建立定植圃。西宁定植苗木41种,正常开花结实的有8种;生长正常无干梢的有8种;干梢较严重,但第二年萌发出新枝的有7种;不能越冬巳被淘汰的有3种。循化定植苗木37种,正常开花结实的有9种;生长正常无干梢的有11种;干梢较严重,但第二年萌发出新枝的有4种。在初步选择的适应音海东部的树种中,可用于退耕还林、荒山治理的生态型树种有6种,可用于庭院及四旁绿化的园林型树种有12种。 相似文献
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本文详细分析了赤峰地区的荒漠化特征,以赤峰市和其5个分区为研究对象,运用数学模型,采用数量化方法,对赤峰地区荒漠化发展程度进行了初步探讨,取得了评价过峰地区荒漠化发展程度的量化指标:土地退化程度指数、灵敏度、土地荒漠化发展程度指数,并提出了相应的治理措施。 相似文献
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廖国华 《中南林业科技大学学报(自然科学版)》1997,(3)
以11种桉树品种的3月龄幼苗为材料,经不同低温处理以后,测定其电导率.结果表明,直接采用叶片处理的电导率(B值)难以对接树的抗寒性作出评价.而采用电解质透出率(B/C值)评价桉按的抗赛性结果较稳定.且以处于拐点附近的处理温度为好.但对抗寒住差异较小的材料,评价结果稳定住用差.对电解质透出率(B/C值)配以Logistic曲线方程,能定量地评价其抗寒性.为早期选择抗寒桉品种提供了科学依据. 相似文献
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Alpo Ranta-Maunus 《Wood Science and Technology》1975,9(3):189-205
Wood is regarded as a viscoelastic material. Creep deformations that arise from variations in the moisture content are described by a theory of hydroviscoelasticity developed by the author. Two different types of behaviour have been apparent: one, arising from a continuously increasing strain with periodic variation in the moisture content, and another with no cumulative effect. The theory has been applied to previously published experimental results concerned with beech, pine, hoop pine, klinki pine, along with birch and spruce plywood. Birch and spruce plywood have been used for experiments concerned with periodically-cycling bending moment and moisture content. The results obtained have been compared with the theory presented. Glue-laminated beams have been subjected to long-term outdoor loading extending for five years. A brief discussion is given of the results obtained. 相似文献
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油茶优良无性系是当前生产上的主要良种.通过采用RAPD分子标记方法,从180多个引物中筛选出22个具有多态性的随机引物进行扩增,得到141个位点,其中有91个是多态位点,以此为基础建立油茶优良无性系的RAPD分子鉴别体系.同时还探索出油茶叶片总DNA的分离技术和建立了RAPD反应体系,为油茶分子技术育种积累了相关的知识并奠定了DNA技术基础. 相似文献