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啄木鸟对森林害虫生态控制作用浅析 总被引:1,自引:0,他引:1
啄木鸟Picidae是杨树蛀干天牛Cerambycidae的重要天敌之一,在控制天牛危害方面具有显著优势,同时对其他森林害虫也有较好的控制作用。本文在对啄木鸟生活习性和特征的观察、对杨树蛀干天牛及其他森林害虫生态控制作用的研究的基础上,阐明了用啄木鸟对杨树蛀干天牛及其他森林害虫实施生态控制,是杨树蛀干天牛工程治理和其他森林害虫防治的有效途径之一,具有广泛的发展前景。 相似文献
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近年来,我国从北美进口了大量木材,随着木材的输入,许多具有毁灭性的林木害虫很可能传入我国,对此,我们应引起高度警惕,加强对木材害虫的检疫。作者参阅了近年来美国森林害虫的发生情况和我国部分口岸截获资料及现已发表的有关木材害虫的文献,依据弗尼斯(Furniss)和卡罗琳(Carolin,1977)编著的《北美西部森林害虫》编译此文。主要介绍 相似文献
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蚂蚁在森林害虫管理中的作用 总被引:4,自引:0,他引:4
捕食性蚂蚁是森林害虫的重要天敌,与同翅目昆虫有共生现象。人类的活动对蚂蚁资源产生巨大影响。建议保护蚂蚁资源,充分发挥蚂蚁在森林害虫管理中的天敌作用 相似文献
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弗尼斯(Furniss)和卡罗琳(Caro-lin)编著的《西部森林害虫》将北美洲西部为害松、杉、桦、白杨及其他混合针叶树的害虫,按其发生范围和为害严重程度,归纳提出了北美洲西部重要的森林害虫31种,包括鞘翅目12种,同翅目1种,膜翅目2种,等翅目1属,鳞翅目15种(见表1)。当然,北美洲西部重要危险性害虫远不止这31种,其中我国规定的外检对象美洲榆小蠹 Hylur- 相似文献
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在我国,森林昆虫作为一门学科是在新中国成立后才建立的,森林害虫的生物防治也随着逐渐发展起来。从建国至1978年,有关我国森林害虫生物防治研究利用,以及1980年以前有关应用生物作用物防治马尾松毛虫情况,请见文献[1][2][3][4]。本文侧重最近几年的新概况。 相似文献
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新疆奇台县近42a气候变化特征分析 总被引:5,自引:1,他引:4
根据新疆奇台县气象站的气温及降水资料,利用线性趋势函数及M ann-kendall突变检测法分析了该地区近42年的气候变化。结果表明:年平均气温与极端最低气温均呈上升趋势,而极端最高气温呈下降趋势;年降水量呈上升趋势。从季节变化来看,除夏季平均气温呈下降趋势,其它各季平均气温均呈上升趋势,其中以冬季增幅最大,秋季次之;各季降水均呈上升趋势,其中以夏季增幅最大,冬季次之。年平均气温未发生突变,而年降水量在1984年发生由少向多的突变。对气温和降水的异常分析得出,暖温年多发生在上世纪80年代后,冷温年多发生在上世纪60、70年代;多雨年主要在近20年,少雨年则多在上世纪60、70年代。此外,该县近42 a来增暖幅度小于全疆和北疆;增湿幅度大于全疆,小于北疆。 相似文献
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综述了我国苜蓿主要病害的分布和危害、病原学、发生规律、抗性种质材料的遗传筛选和鉴定及综合防治等方面的主要研究进展,并提出了今后的研究方向和发展目标。 相似文献
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Cees Waalwijk Pieter Kastelein Ineke de Vries Zoltan Kerényi Theo van der Lee Thamara Hesselink Jürgen Köhl Gert Kema 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(7):743-754
The re-emergence of fusarium head blight throughout the world and especially in Western Europe prompted a survey of the situation in the Netherlands. To allow for a high throughput screening of large numbers of samples, a diagnostic PCR method was developed to detect the most common species of Fusarium occurring on wheat. Seven primer pairs were tested for their ability to identify isolates of Fusarium avenaceum, F. culmorum, F. graminearum, F. poae, F. proliferatum and Microdochium nivale var. majus and M. nivale var. nivale. Each primer pair only generated a PCR product with the corresponding Fusarium species and all PCR fragments had different molecular sizes. This allowed the generation of these amplicons using a mixture of all seven primer pairs. The robustness of this multiplex PCR encouraged us to screen a large series of isolates collected in 2000 and 2001. In both years 40 fields were sampled leading to a collection of 209 isolates from 2000 and 145 isolates from 2001. The results of the multiplex PCR demonstrated that F. graminearum was the most abundant species in the Fusarium complex on wheat in both years. This is in sharp contrast to reports from the 1980s and early 1990s, which found F. culmorum as the predominant species. Primers derived from the tri7 and tri13 genes, which are implicated in the acetylation and oxygenation of the C-4 atom of the backbone of the trichothecene molecule, were used to discriminate between deoxynivalenol and nivalenol (NIV) producers. The populations of F. culmorum and F. graminearum both showed a slight increase in NIV-producers in 2001. 相似文献
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弹状病毒含有单链负义RNA基因组,寄主范围比较广泛,能侵染无脊椎动物、脊椎动物以及植物等寄主,对人类的健康、农作物产量和自然生态系统造成严重威胁。植物弹状病毒主要根据复制场所分为细胞质弹状病毒属Cytorhabdovirus和细胞核弹状病毒属Nucleorhabdovirus,其基因组由单股负链RNA组成。此外,Dichorhavirus和Varicosavirus病毒属是两个新鉴定的植物弹状病毒属,其特征是具有二分体基因组。本文着重介绍危害我国农作物的几类植物弹状病毒,对它们的病理学、病害流行、基因组信息以及传播媒介进行概述,为中国植物弹状病毒病害的研究提供理论依据。 相似文献
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Variation in pesticide residues in space and time has not been investigated systematically in spite of the large variability found at single scales (e.g. between trees or orchards). Information on variability at different scales will support the development of sampling methods and more reliable prediction of residues. Experiments were conducted to quantify the spatiotemporal variability in initial spray deposit on apple leaves and fruit using a substitute tracer (zinc EDTA chelate). Five hierarchical spatial scales were defined as (1) between orchards, (2) between plots within an orchard, (3) between trees within a plot, (4) between zones within a tree and (5) between leaves/fruit within a zone. Similarly, two temporal scales were defined as (1) between applications within a single year and (2) between years. The initial zinc concentration was approximately log-normally distributed; the variability in initial deposit concentration was greater on leaves than on fruit. The average initial zinc deposition was significantly greater in the top and outside zones than in the middle zones within individual trees. The most important scale for driving residue variability is the within-zone unit-to-unit variation, contributing to 71 and 49% of the observed variability for leaf and fruit samples respectively. Variability at other scales was related to the variation in the tree architecture. The results indicated that stratified sampling on the basis of within-tree zone structures, with the effort focused on within-zone sampling, should be used for the determination of pesticide residues. 相似文献