共查询到20条相似文献，搜索用时 390 毫秒
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中原地区丹红杨插干造林技术研究 总被引：1，自引：0，他引：1
丹红杨是中国林业科学研究院2003年培育成功的新一代超速生抗虫杨,雌株。耐桑天牛、易生根、速生（年胸径生长量达5.8 cm,年平均高生长量4.9 m）。为了提高丹红杨的造林成活率,进行了杨树插干深栽造林试验。试验结果表明,丹红杨采用插干深栽造林方法与传统的带根植苗造林相比,具有成本低、成活率高、生长量大等特点,是一种比... 相似文献
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通过对引进的OP-367、DN-34、NM-6等3个北美杨品种与当地优良品种进行育苗、造林试验,结果表明：苗期DN-34杨封顶较早,高生长与其他品种有一定差异,造林成活率最高,为94.7%;扦插造林3 a来,OP-367杨生长量最大,胸径6.93 cm,树高8.8 m;造林5 a来,3个品种未发生冻害、风折等现象。 相似文献
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毛新×银灰杨扦插育苗技术哲盟林研所冯政夫毛新×银灰杨是毛白杨与新疆杨以及新疆杨与中国山杨的双杂交组合。该品种根幅庞大，具有耐瘠薄、干旱，抗污染和抗风沙等特性，是沙地造林的先锋树种，该品种木材色白，在造纸中不需要漂白，雄株树姿雄伟壮丽，是工矿、居民区、... 相似文献
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春季杨柴植苗造林，因风沙和干旱的威胁，造林成活率很低，此时，沙丘中上部土壤墒情差只能在丘间低地植苗，同时，易受鼠兔的危害。将培育的杨柴壮苗条窑冷藏，控制其萌芽，直到６、７月，在雨季到一时进行移栽，收到良好的造林效果。 相似文献
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84K杨硬枝扦插育苗技术要点 总被引：1，自引：0，他引：1
８４Ｋ杨是韩国选育的一个白杨 派杂种无性系；在韩国杨树造林面积 中占到２０％，主要栽在１５度以下的 坡地上，用于山区绿化。中国林科院 引入后，在陕西等“三北”地区经过 １４ 年引种试验，表现良好。２０００年８月 ４日通过林木良种审定委员会审定。 ８４Ｋ杨扦插育苗比毛白杨和河 北杨容易，成活率可达９５％以上，但需要注意的是， ８４Ｋ杨毕竟是白杨派树种，扦插育苗不能象黑杨派和 青杨派树种那样粗放操作，必须掌握以下技术要点，并 认真实施，才能达到理想的成活率。 一、苗圃地的选择与整地 育苗地要选肥沃、深厚的中性壤质… 相似文献
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杨树是徐滩平原地区重要的速生用材树种，特别是I－69杨，它生长迅速，适应性广，抗逆性强，是目前徐滩地区造林的主栽树种，深受广大农民喜爱。但由于该地区冬、春季较早，加之I－69标本身成活较难，故自推广以来，造林成活率低一直是困扰该地区林业发展的一个突出问题。为探讨影响I－69杨造林成活率的主要因素．对徐州市所属7个县（市、区）近年栽植的I－69杨成活情况连续两年进行了调查，现将调查结果总结分析如下：1调查时间、内容和方法调查时间为1992年5月下旬和1993年5月上旬。调查采用临时样地的方法，记载各样地的栽植成活率．栽… 相似文献
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为验证多树种合理配置抗御杨树天牛灾害的效果,在宁夏新华桥种苗场的试验林内,选取受光肩星天牛危害的3种配置模式的林分为样地,通过对新疆杨标准木做树干解析.比较3种配置模式中新疆杨的单株总生长量,结果除胸径外,树高和材积的总生长量均存在显著差异;单株材积总生长量大小顺序为新疆杨和复叶槭混交林＞新疆杨和合作杨混交林＞新疆杨纯林,即混交林中天牛对新疆杨危害不同程度地小于新疆杨纯林.比较3种模式林分在单位面积上的总材积生长量,结果为新疆杨和复叶槭混交林＞新疆杨纯林＞新疆杨和合作杨的混交林.同时考虑目标树种的单株材积生长量和该配置模式单位面积上的总材积生长量,新疆杨和复叶槭混交林是3种模式中最理想的. 相似文献
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The capacity of trees to recover from mechanical disturbance is of crucial importance for tree survival but has been primarily investigated in saplings using artificially induced wounds. In this study, mature Larix decidua Mill., Picea abies (L.) Karst. and Abies alba Mill. trees growing on alpine slopes that were wounded by naturally occurring rockfall were analyzed to determine their efficiency in overgrowing wounds. In total 43 L. decidua, P. abies and A. alba trees were sampled. First, 106 samples from 27 L. decidua and P. abies trees were analyzed to reconstruct yearly and overall overgrowth rates. Cross sections were taken at the maximum extension of the injury and overgrowth rates were determined on a yearly basis. Results clearly showed that L. decidua overgrew wounds more efficiently than P. abies with an average overgrowth rate of 19° and 11.8° per year, respectively. The higher on the stem the injury was located, the faster the wound was closed. Young and small trees overgrew wounds more efficiently than older or thicker trees. In contrast, no correlation was observed between injury size or increment before/after wounding and wound closure. Second, cross sections from 16 L. decidua, P. abies and A. alba (54 injuries) were used to assess closure rates at different heights around the injury. Overgrowth was generally smallest at the height of the maximum lateral extension of the injury and increased at the upper and lower end of the injury. The efficiency with which L. decidua closes wounds inflicted by rockfall makes this species highly adapted to sites with this type of mechanical disturbance. 相似文献
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Electrical pollution is a worldwide concern,because it is potentially harmful to human health.Trees not only play a significant role in moderating the climate,but also can be used as shields against electrical pollution.Shielding effects on the electric field strength under transmission lines by two tree species,Populus alba and Larix gmelinii,were examined in this study.The electrical resistivity at different heights of trees was measured using a PiCUS sonic tomograph,which can image the electrical impedance for trees.The electric field strength around the trees was measured with an elf field strength measurement system,HI-3604,and combined with tree resistivity to develop a model for calculating the electric field intensity around trees using the finite element method.In addition,the feasibility of the finite element method was confirmed by comparing the calculated results and experimental data.The results showed that the trees did reduce the electric field strength.The electric field intensity was reduced by 95.6%,and P.alba was better than L.gmelinii at shielding. 相似文献
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The hybridization experiment was initiated in 1975, in which the parents ofP. davidiana were collected from Dailing, Heilongjiang Province,P. suaveolens were from Baicheng,P. simonii from Zhaodong of Heilongjiang Province, andP. tremula from Shanxi Province. Clones No 1333 ofP. Alba × P. davidiana and No 1132 ofP. davidiana × (P. alba × P. davidiana F1) had greater genetic variation and heritability in clones tested.
(Responsible Editor: Dai Fangtian) 相似文献
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Oviposition preference of Anoplophora glabripennis emerging from five host tree species under field conditions 总被引：1，自引：0，他引：1
Xiong-fei Yan Xiao-juan Li You-qing Luo Zhi-chun Xu Gui-fang Tian Tie-lin Zhang 《中国林学(英文版)》2008,10(1):23-26
The Asian longhorned beetle （ALB）, Anoplophora glabripennis （Motschulsky） is a polyphagous woodborer of hardwood trees. In order to well understand the oviposition preference of A. glabripennis emerging from different larval host tree species, we selected five common host tree species in the field and evaluated its oviposition preferences. The five host tree species are Acer negundo （AN）, Salix matsudana f. lobato-glandulosa （SM）, Populus nigra L. var. thevestina （Dode） Bean （PN）, P. simonii × P. pyramidalis cv. Opera 8277 （PS） and P. alba var. pyramidalis （PA）. Results show that adult beetles emerging from these five tree species almost have the same oviposition phenomenon. All adult beetles, except those emerging from PS, chewed the highest potential sites and laid most eggs on AN trees. Adult beetles emerging from AN, PN, PS and PA did not chew any sites nor laid any eggs on PA trees. These results showed that adult A. glabripennis emerging from the five host tree species did not show any clear oviposition preference for their larval host tree species in the field but they did present the most obvious preference for AN and the lowest preference for PA. 相似文献
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为了探讨银白杨、马氏杨及银白杨×马氏杨杂交子代间的遗传多样性参数及个体聚类关系,利用8对引物对银白杨、马氏杨及银白杨×马氏杨杂交子代4个样本进行了AFLP分析。结果表明,8对引物共扩增出780条扩增谱带,其中多态性条带数为715条,多态性比例为91.65%,平均有效等位基因数为1.5017,Nei’s平均遗传多样性指数为0.3065,Shannon平均信息指数为0.4679。不同杂交子代在E-AAC/M-CAG引物对上均有特异性位点,这些特异位点可用于品种鉴定。聚类研究发现,在相似系数为0.76时,试验样品分成2个AFLP群,其中马氏杨为1个AFLP群,银白杨及2个杂交子代为1个AFLP群;当相似系数为0.78时,银白杨和2个杂交子代的AFLP群又划分为2个亚群,其中杂交子代1和杂交子代2聚合为亚群1,银白杨为亚群2。本研究的结果多态性比例很高,对样品的区分率达到100%,为杨树AFLP分析检测提供了指导借鉴价值。 相似文献
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In order to investigate different kinds of cellulase in insect pests, we selected male and female adults of Anoplophora glabripennis （Motschulsky） emerging from four different host species （Populus alba var. pyramidalis, P. nigra var. thevestina （Dode） Bean., P. simonii × P. pyramidliscr cv. Opera 8277 Hsu. and Salix matsudana f. lobato-glandulosa） as our research material. The enzyme activitives of three kinds of cellulase in the intestines of the adult insects were measured. The Cx-cellulase isozymes were detected with a CMC-incorporated polyacrylamide gel. The results show that： there are no statistically significant differences between the enzyme activities of males and females emerging from the different host species. The order of magnitude in activity is： Cx-cellulase 〉 β-glycosidase 〉 C1-cellulase. When the adults emerge from the same host species, there are no statistically significant differences between male and female enzyme activities of β-glycosidase and C1-cellulase, but the enzyme activity of Cx-cellulase of males is clearly higher than that of females. The patterns and migration of Cx-cellulase isozymes of males and females emerging from differ-ent hosts trees are clearly not different, and neither are they different when emerging from the same hosts. 相似文献
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《林业研究》2020,31(5)
Populus alba is a foundation species in evolutionary and ecological studies in the northern hemisphere.In this study, the chloroplast genome and gene map of P.alba were constructed. The P. alba chloroplast genome is156,505 bp in length comprising a large single-copy region, two inverted repeat regions and a small single-copy region. The genome contains 131 genes, including 86 protein-coding genes(77 PCG species), eight ribosomal RNA genes(four r RNA species) and 37 transfer RNA genes(30 t RNA species). Phylogenetic analysis indicates that all Populus chloroplast genome sequences are clustered together and divided into three large branches.Among reported Populus chloroplast genomes, the leuce section formed monophyletic, indicating that all Populus spp. have a common maternal ancestor. P. rotundifolia and P. tremula are closely related and are sisters to P.davidiana. P. alba is closely related to P. adenopoda.Population genetic research in ecology and evolution may be easily developed through chloroplast genomes as they are conserved. This research will benefit future studies related to Populus, one of the world's most ecologically and economically important genera. 相似文献