共查询到18条相似文献,搜索用时 63 毫秒
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杉木立木干基腐朽病是杉木发生普遍而又广泛的一种病害,在成熟林分中发生率在25%左右,造成木材约1.44%的材积损失。该病害可发生于杉木中幼林,且随林龄的增长而加重,并与环境因子相关,林分遭受自然、人为等因素损害导致创伤有利于病原菌的入侵;同一山场下坡比上坡发生严重,阴坡比阳坡发生严重。 相似文献
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外担子菌属真菌的研究综述 总被引:1,自引:0,他引:1
本文对外担子菌属(Exobasidium)真菌的寄主植物及其症状、寄生性及致病机理、形态学、生活史、寄主与病原关系的超显微构造、培养性状、生理学性质及分子生物学,特别是在分类学等方面的研究状况做了综述。外担子菌属的真菌在亚洲、北美、欧洲及大洋洲都有分布,世界记载约有50种,引起5科木本植物的细胞增生性和肥大性病害,其症状类型多,这可能与植物激素含量的变化有关;该菌的生活史还不太清楚;其担孢子和分生孢子萌发后,芽管可以从气孔、伤口侵入或者从表皮直接侵入寄主叶组织,菌丝存在于寄主细胞间隙,产生吸器状构造;本属菌的分类依据因研究者不同而异;近年对本属菌的DNA碱基GC含量以及28SrDNAPCRRFLP的研究结果体现了本属菌的系统分类学的发展趋势。 相似文献
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异耦阿扁叶蜂生物学特性及防治试验初探 总被引:3,自引:0,他引:3
在川东林区首次发现异耦阿扁叶蜂危害马尾松。该虫一年发生一代。7月中旬以老熟幼虫下树入土作室越冬,翌年3月中、下旬化蛹,4月上旬成虫羽化,5月下旬卵孵化。幼虫5至7龄。该虫幼虫期可被蜘蛛、蚂蚁取食和白僵菌感染。经试验多效杀虫灵、森保Ⅰ号、有机磷及拟除虫... 相似文献
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异尾华枝Xiu生物学特性及防治 总被引:1,自引:0,他引:1
异尾华枝XiuSinophasma mi3rabile Gunther在华东地区是一种新发现的危害壳斗科树木的重要食叶害虫。在浙江泰顺1年发生1代,以卵越冬,若虫和成虫大量取食寄主树叶造成树木生长衰弱甚至枯死。该文介绍了该虫的年生活史、发育过程、生活习性、取食量、天敌种类和防治方法,采用燃放烟剂、树干注药、地南药等措施,防治效果显著。 相似文献
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将莰烯分别与1,2-丙二醇及1,3-丁二醇加成所得产物1-[(1,7,7-三甲基双环[2,2,1]庚-2-基)氧]2-丙醇及4-[(1,7,7-三甲基双环[2,2,1]庚-2-基)氧]-2-丁醇,氧化得到两只新型的可用作香料的萜醚酮,1-[(1,7,7-三甲基双环[2,2,1]庚-2-基)氧]丙酮,与4-[(1,7,7-三甲基双环[2,2,1]庚-2-基)氧]-2-丁酮。 相似文献
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夏玛林区森林病害防治技术研究 总被引:1,自引:0,他引:1
<正>甘肃省夏玛林区的森林在人为破坏和不良自然环境条件胁迫下所发生的林木病害,常造成林业生产的重大经济损失,使幼林的生长受到严重威胁导致森林生态系统健康状况不 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):303-308
The likelihood of detecting decay present in Norway spruce trees when taking bore core samples at breast height or at stump height was analyzed in two stands. The actual numbers of decayed trees were obtained after the trees were felled. More than 80% of the decay extending to breast height level was detected by taking core samples at that level. However, these core samples revealed only 40–70% of the actual amount of decay present at stump height. At stump height a higher portion of the total amount of decay present was revealed. Heterobasidion annosum was detected in 69 and 77% of the decayed trees in the two stands. Misjudgements occurred mainly where either (i) decay was present at stump height but not at breast height or (ii) when the decay column had a lateral position. At breast height the probability of finding lateral rot columns was higher than at stump height. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):74-81
An empirical model is presented to forecast the incidence of root rot at stand level. In addition, the impact of different thinning programmes on the incidence of root rot is evaluated. The model is based on data from 152 permanent forest research plots of pure Picea abies in southern Sweden, within which the incidence of root rot at stump height in thinned trees has been recorded after each thinning since 1950. In total, about 20 000 stumps have been studied. According to simulations with the model, areas previously used as fields or for grazing are particularly susceptible to root rot, while old hardwood sites are less susceptible. Furthermore, simulations with the model imply that the earlier, the harder or more often a stand is thinned, the faster will be the development of root rot. 相似文献
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森林昆虫和病原物的害与益 总被引:7,自引:1,他引:7
森林昆虫和病原物虽然能引起林木损伤与死亡,但它们在森林演替,物质循环和能量流动,食物来源,创造野生动物生境等方面都作了积极的贡献,而且在一个生态系统发展前景中,对于森林生物多样性,土壤肥力,森林的长时期健康和稳定性等方面,它们的促成作用也是必不可少的,因此,森林经营者应当考虑昆虫和病原物的害与益的两方面作用。 相似文献
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报道了中国小兴安岭云杉树上一种新干基白腐病 ,其病原菌为鳞片昂氏多孔菌 Onnia leporina( Fr.) H.Jahn。该病主要发生在成熟林分 ,造成受害木干基白腐 ,被侵染树木极易风折或风倒而死亡。根据中国的材料对该病病原菌进行了宏观和微观的详细描述 ,并与欧洲的材料进行了对比。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(2):165-176
Decay and root rot caused by Heterobasidion annosum (Fr.) Bref. s. lato is the most serious disease of Norway spruce [Picea abies (L.) Karst.]. Mathematical models of disease development have recently been developed for forestry planning purposes. Functions for predicting the probability of decay were developed from two data sets, one comprising trees and another comprising stumps. From the years 1983–2001, 45,587 Norway spruce trees from the Swedish National Forest Inventory (NFI) were analysed for decay incidence at 1.3 m height and correlation with environmental conditions. The decay frequency increased in all studied regions from the first to the second half of the period for trees with comparable tree and environmental attributes. In a stepwise logistic regression, sets of functions were developed showing significance regarding stand age, site index class, temperature sum, height above sea level, diameter at 1.3 m, soil moisture and texture, proportion of spruce and eastern coordinates. The functions were calibrated and validated with a data set from the Swedish NFI from the years 1993–2002 comprising 7,893 stumps. The calibration of decay incidence at breast height to stump height doubled the decay incidence (R 2=0.85). The developed functions could be used to establish initial conditions for dynamic modelling of disease and in strategic planning. 相似文献