共查询到18条相似文献,搜索用时 62 毫秒
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无公害粘虫胶防治枣树害虫试验研究 总被引:1,自引:1,他引:1
通过对枣树4种主要害虫进行无公害粘虫胶防治试验,发现对枣粉蚧、枣尺蛾和食芽象甲的防治效果达到90%以上,其中对枣树红蜘蛛的防治达99.5%以上,分别较对照提高了70%和75%以上。有效控制了枣红蜘蛛、枣粉蚧、食芽象甲和枣尺蛾的危害,平均每个粘虫胶环粘杀红蜘蛛1870头以上,粘杀枣粉蚧154头以上,食芽象甲4头以上,枣尺蛾5头以上,叶片被害率(包括有虫叶率)均控制在1%以下,达到了很好的防治效果。并且操作简便、节约用水、不造成环境和果品污染,有利于实现果品无公害生产。 相似文献
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榆紫金花虫Ambrostoma quadrii-mpressum(Motschulsky)是目前为害榆类较严重的害虫之一。近年来在锦县地区大面积发生,有的被害林木因连续几年未能发叶,成片枯死。其中大凌河林场从河南引进的大面积白榆林,连续两年叶子被吃光。在先后使用药剂喷杀、人工捕杀等方法都未能奏效的情况下,于1987年根据榆紫金花虫取食上、下树爬行的习性,我们采用了无毒粘虫胶涂环的方法,进行小面积防治试验,收到了良好的效果,杀虫率达90%以上。 相似文献
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无公害粘虫胶在枣树上的应用技术 总被引:2,自引:1,他引:2
1 无公害粘虫胶的特点无公害粘虫胶是由几种生物制品合成的一种胶。一般风吹、日晒、雨淋对其粘着力影响不大。在3~ 10月份期间 ,每次涂在树干上有效粘虫期达 2个月以上。它的粘着力很强 ,身长 2cm以下的害虫一旦被粘 ,难以挣脱。2 使用方法及注意事项先用 1.5cm宽的胶带在枣树主干光滑部位缠绕一圈 ,然后将粘虫胶均匀地涂在上面。粘虫胶因无毒可直接用手涂用。使用时不要粘着杂草等 ,防止“搭桥”。另外涂胶不要太薄 ,以防影响效果。河北省林业科学研究院生产的无公害粘虫胶 ,最佳用量是直径 13cm左右的枣树用胶 1.5~ 2 g ,每株… 相似文献
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天津开发区园林植物害虫无公害防治技术 总被引:3,自引:0,他引:3
通过对天津开发区园林害虫的种类和危害情况的调查,摸清了开发区园林主要害虫有食叶害虫、蛀干害虫、刺吸害虫和地下害虫4大类;遵循安全、保护环境和维护生态平衡的原则,摸索出生物防治方法、信息素的应用、植物农药烟参碱的应用、仿生农药灭幼脲系列药剂的应用、无机农药的应用、人工和物理机械方法的应用、栽培防治方法的应用及植物检疫方法的应用的几种无公害防治方法,防止了环境污染和副作用的产生。 相似文献
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利用塑料瓶投放诱饵设置诱捕井的办法防治森林害鼠 ,1hm2 设 5 0个诱捕井 (10m× 2 0m ) ,2 4h诱捕率 90 % ,防治效果 90 6 %。 相似文献
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M. Okuma 《Wood Science and Technology》1976,10(1):57-68
Summary The effect of the number and the location of glue lines in the cross section on the bending properties has been studied on plywood bonded with tannin-formaldehyde adhesive. The thickness of glue line has also been investigated. By comparing the theoretical equations with the empirical ones, we can get the thickness of the glue line of wattle tannin adhesive plywood to be 0.15 mm. As for Young's modulus in bending of the glue line in the plywood, it is calculated to be 219 800 kg/cm2 and is larger than that of the glue line of phenolic resin bonded plywood. In relation to the veneer, Young's modulus of the veneer under the condition of plywood assembly seems to be slightly larger than that of the veneer under the free condition.The author wishes to express his gratefulness to CSIRO of Australia for a Fellowship during the tenure of which this research was carried out. The direction and cooperation of Mr. K. F. Plomley, Dr. P. Grossman and Mr. P. Collins, CSIRO of Australia are gratefully acknowledged 相似文献
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Adhesion problems sometimes occur during the production of laminated wood products. To minimize such quality problems, there
is a need for a nondestructive test that can provide continuous control of the process and the product. This study presents
results from measurements performed to evaluate the potential of pulse thermography as a method to detect glue deficiency
in laminated wood. Defect depth, defect size, and degree of glue deficiency have been varied. The surface layer was made of
merbau (Intsia bijuga) and the substrate of Scots pine (Pinus silvestris). The results showed that pulse thermography is a promising tool for detecting glue deficiency underneath the thin laminated
wood surface layers, mainly because of the short inspection time. Lack of glue with a minimum thermal defect size of 3 was
detectable (thermal defect size is defined as the quotient of defect size and defect depth). The penetration depth was 1.0 mm
and the highest contrast, 0.62°C, was achieved for one of the largest defects (24 mm) below the thinnest (0.5 mm) surface
layer after 1 second. Starved glue joints showed about half the contrast compared to areas with total lack of glue.
Received: April 24, 2002 / Accepted: July 26, 2002
Acknowledgments We gratefully acknowledge the support of this work from the Knowledge Foundation and The Swedish Wood Association. 相似文献
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