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辽宁杨树蛀干害虫发生与林分因子的关系 总被引：1，自引：0，他引：1
通过对辽宁省杨树主要栽植区杨树蛀干害虫发生情况、杨树品种、林龄、造林密度等林分因子的全面调查,研究了3种蛀干害虫的发生与林分因子的关系。结果表明:辽宁主要的杨树蛀干害虫有3种,即杨干象、白杨透翅蛾和青杨天牛,其中普遍发生并危害严重的是杨干象。杨树品种不同蛀干害虫的发生程度也不同,其中107杨、108杨、127杨、N64、W120以及中林46受害较重。不同品种杨树的杨干象危害情况受林龄影响明显,林龄越小受害越严重;在受害程度一般的品种中杨干象的危害受种植密度影响明显,种植密度越大受害越严重。 相似文献
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不同杨树品种对杨树烂皮病菌的抗性差异 总被引：1，自引：0，他引：1
杨树烂皮病是杨树的重要病害。在我国北方风沙灾害严重的地区,或早春冻害严重的年份,病情发展迅速,往往造成新植幼树及大树的成片枯死,严重威胁着杨树人工林的发展。据调查,在自然状态下,杨树的不同品种其受害程度往往表现出较为明显的差异。为了选择抗烂皮病的优良杨树品种,以预防病害的发生,对不同的杨树品种进行了抗病性的测定。 1 供试材料杨树烂皮病菌,系1985年从病树上分离的无性阶段(Cytospora chrysosperma)。 相似文献
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为了科学防治杨树湿心材,本研究对湖北省不同品种、年龄、栽植密度及立地条件的杨树湿心材发生情况和致病微生物开展了初步研究.结果表明：湖北省杨树湿心材发生十分严重,湿心材严重程度除了受到遗传控制外,还受到立地、气候等环境条件协同影响.湿心材成因复杂,杨树自身生理因素、病原微生物及外界环境均对杨树湿心材形成有影响. 相似文献
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据调查,近几年,紫纹羽病在山东发生蔓延较快,潍坊市所辖十二个县、区均有不同程度的发生.尤以诸城、五莲、临朐等地发生较重.危害树种有杨树、柳树、刺槐、椿树、紫穗槐等。经对河滩500亩十七年生的杨树、刺槐混交林的详细调查发现,发生面积190亩,其中轻的70亩,发病率11%,感病指数6.4,严重的120亩,发病率77%,感病指数60。 相似文献
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Xiang Cunti Sun Haifeng Li GuishengNortheast Forestry UniversityWu Xingyin Li Zhuo DangWenqiang Zhang Jinghua Zou XipinAcheng Forest Bureau of Heilongjiang Province 《林业研究》1991,2(1):48-55
The bacterial swollen stem canker of poplar is prevalent in planted poplars ofnortheast China.Serious damage occurs in the form of necrosis,putridity,cankers,swollen stemsand discolored wood of trunks and branches of young and mature trees.Tests of allergic reaction,pathogenicity,culture characteristic,Gram stain and anaerobic culture revealed that the pathogen isErwinia sp.Its occurrence depends mainly on the predisposing factors of the disease among whichthe susceptibility of poplars is the most important one.The disease becomes widespread in associa-tion with low-lying and high-humidity terrain,frost injury,node wounds,insect damage,and prun-ing and other mechanical wounds.Harmful factors promote the disease. 相似文献
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G. Von Bazzigher 《Forest Pathology》1973,3(2):71-82
Wound decays in spruce stands following bark stripping . 2083 trees in 91 sample plots on four trial areas (24 ha) were examined for bark stripping and decay. Only 25% of trees showed no injury. Of the injured trees, 73% showed some degree of decay, 10% discoloration. and 17% neither decay nor discoloration. Of the wood destroying fungi isolated Fomes annosus was dominant and appeared to be the most important and widespread of the wound inhabiting fungi in the test area. Besides the Basidiomycetes a considerable number of other fungi was isolated. The most frequent was Cylindrocarpon cylindroides var. tenue. 相似文献
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GaoJianmin ZhangBiguang ChangJianmin 《中国林学(英文版)》2004,6(2):50-55
Buerger maple (Liquidambarformosana Hance) is a kind of wood that is easily discolored. This paper tries to obtain satisfactory color and a broad prospect in the utilization of buerger maple by induced discoloration. The authors analyze the mechanism of induced discoloration of buerger maple based on the analysis of visual physical parameter, the infrared spectrum (IRS) and the scanning electron microscope (SEM) under different drying conditions. The result shows that it is feasible to induce discoloration during the drying process. The wood color tends to be red and fuscous during inducing discoloration of buerger maple.The induced discoloration mechanism is: 1) the high temperature and humidity accelerates the oxidation reaction of polyphenol,leuco-fancy pigment and tannin, which changes the wood color to red; 2) the hydroxy (-OH) is oxidized and the carbonyl (-C=0),carboxyl (-COOH), ester and ketone groups form during the high temperature steaming, which results in wood piece discoloration. 相似文献
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Toshihiro Yamada 《Journal of Forest Research》1998,3(2):103-109
The participation of active defense responses in the limitation of fungal spread in the sapwood of living sugi tree was determined.
Isolates ofGuignardia cryptomeriae were inoculated to living trees, fresh logs, frozen and thawed logs and autoclaved logs, and the spread of wood discoloration
and fungal hyphae was assessed. In autoclaved logs and freeze-treated logs, wood discoloration and reaction zone formation
were not observed, and fungal hyphae of both of virulent and avirulent isolates grew rapidly in the wood. In fresh logs, wood
discoloration and the formation of a pale reaction zone and transition zone were observed. Virulent isolates spread rapidly,
but the spread of avirulent isolates was inhibited. In living trees, wood discoloration was observed and reaction zones were
formed at lesion margins. These results indicated that constitutive defense mechanisms had no effect on the spread of both
of virulent and avirulent isolates, and that active defense responses were important in the limitation of spread of fungal
hyphae, hence in the limitation of wood discoloration. Further, it appeared that avirulent, but not virulent, races ofG. cryptomeriae were easily inhibited even by weak host responses.
This study was presented at 105th and 106th Annual Meeting of the Japanese Forestry Society. 相似文献
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Giuliana Deflorio Craig Johnson Siegfried Fink Francis Willis Mathew Robert Schwarze 《Forest Ecology and Management》2008
Development of decay and/or discoloration was assessed in the functional sapwood of one coniferous and three deciduous trees after wounding and artificial inoculation with six wood decay fungi. Living stems of mature Douglas fir, beech, oak, and sycamore trees were wounded in spring 2002 and immediately inoculated with brown, white, and soft rot fungi. Extent of discoloration and decay, wood weight loss, and total phenols in the reaction zone (zone of active response at a dynamic interface between living sapwood and wood colonized by decay fungi) were assessed 16 and 28 months after inoculation. 相似文献
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