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81.
参照国际上林业有害生物危险性分析(Pest Risk Analysis,简称PRA)方法,从有害生物的分布状况、定殖和扩散的可能性、潜在的危害性、寄主植物的经济重要性以及危险性的管理难度等方面进行定性和定量分析,对杨树烂皮病的危险性做出综合评价,其风险评估值(R)为1.49。评价结果表明,杨树烂皮病在辽阳地区属中度危险性的林业有害生物,具有扩散蔓延的危险,对绿化、农田林网、防护林体系构成较大的威胁,应积极采取有效措施除治。  相似文献   
82.
近几年,作者对海南芒果主产区的儋州、白沙、昌江、东方、乐东、三亚6个市县代表性果园进行芒果害虫调查。鉴定出海南省芒果作物上的害虫共计96种,分属8目44科,其中,等翅目1科1种,直翅目1科4种,半翅目6科12种,同翅目12科28种,缨翅目1科1种,鳞翅目12科32种,鞘翅目9科15种,双翅日2科3种。对芒果为害较重且分布较广的害虫主要有芒果扁喙叶蝉Idioscopus incertus(Baker)、脊胸天牛Rhytidodera bowringii White、横纹尾夜蛾Chlumetia transversa Walker、芒果剪叶象Deporaus marginatus Pascoe、橘小实蝇Bactrocera dorsalis(Hendel)、茶黄蓟马Scirtothrips dorsalis Hood、龙眼长跗萤叶甲Monolepta occifuvis Gressitt et Kimoto和芒果叶瘿蚊Erosomyia mangiferae Felt共8种o  相似文献   
83.
Control of invertebrate pests in broad-acre agriculture largely relies on the application of broad-spectrum pesticides, however resistance problems and environmental concerns are driving a search for alternatives including more selective products. Here we explore the feasibility of using novel chemical groupings in the control of problematic pests that attack germinating pastures and grain crops in Australia. A modified laboratory bioassay is described for testing the response of several invertebrate pests to pesticides that have contact and systemic/translaminar properties. Two contact pesticides (fenitrothion and gamma-cyhalothrin) and three pesticides with strong systemic/translaminar properties (lambda-cyhalothrin, abamectin and diafenthiuron) showed promise for control of the collembolan Sminthurus viridis and four mite pests (Halotydeus destructor, Balaustium medicagoense, Penthaleus falcatus and Bryobia sp.). No single pesticide emerged as the most efficacious against all these pests, highlighting the need for correct pest identification before making control recommendations. Incorporating these new chemical options into pest control programs may help to control emerging pests and counter pesticide resistance issues. Selective pesticides in particular are likely to be compatible with integrated control programs that promote the establishment and maintenance of beneficial natural enemies.  相似文献   
84.
Vermicomposts are produced through interactions between earthworms and microorganisms in the breakdown of organic wastes. Aqueous extracts were prepared in commercial brewing equipment (Growing Solutions Inc.) from vermicomposts processed from pre-consumer food waste. The ratio of vermicompost to water was 1 to 5 v:v to produce a 20% aqueous solution. The effects of soil drenches at dilutions of 20%, 10%, and 5% vermicompost extracts, were compared with those of deionized water, in the suppression of green peach aphids, mealybugs, and two spotted spider mites attacking tomatoes and cucumbers, in greenhouse cage experiments.  相似文献   
85.
综述了我国甜菜害虫化学和生物防治方法等研究进展,提出了今后研究发展方向。  相似文献   
86.
王世国  石兴国 《河北农业科学》2011,15(1):27+30-27,30
从栽植方法、抚育管理以及病虫害防治等方面,介绍了泡桐丰产栽培的技巧。  相似文献   
87.
The researches were carried out in 2007, 2008 and 2009 at Cluj-Napoca (Romania), in laboratory and field conditions (grassland ecosystems), in four experiments. Our purpose was to study and use some ecological pest control methods based on indirect and direct strategies: (1) the harmful fauna monitoring in grassland ecosystems and useful fauna identification (by visual control, manually collecting, striking method on a tarpaulin); (2) the use of some physico-mechanical and biotechnical methods (use of barriers-vessels, repellents, attractant traps-alimentary, visual) to control the pests. The researches concerning the indirect strategies, carried out from Mars 2007 to September 2009. There were identified 28 pest species and 29 useful ones. The direct strategies to control the pests consisted of 3 experiments. The use of colored traps with water (August 2008) on a meadow with ryegrass and clover, in 6 variants (white, silver, orange, green, blue and red) + control (yellow), recorded a very good efficacy at all variants excepting the red trap (variant 6). The use of repellents (August 2008), absinth decoction (against aphids and ants), bracken extract (against aphids and snails), common tansy decoction (against ants and soil pests) and kaolinite (against a large amount of pests), recorded good results removing the pests. The attractant traps with alimentary baits (beer), meant the use of 10 vessels on a 1000 m2 area, which captured 200 slugs (August 2009). All three methods recorded a good efficacy against the pests.  相似文献   
88.
The threat posed by invasive alien species to global crop production and biodiversity is recognized as one of the major drivers of global change today. Here we report on a successful implementation and operational use of new technology to support risk- and crisis management in the case of fighting an invasive plant disease. The open geospatial standards Web Feature Service Transaction (WFS-T) was implemented in software for GPS-enabled mobile phones communicating with a GeoServer backend in order to track down and eradicate disease outbreaks and susceptible host plants. This new technology offering georeferenced events online from field provides new possibilities for real time action in risk and crisis management.  相似文献   
89.
贺京  陈涛  方丽  陈玉梅  李勇峰  贺红志 《安徽农业科学》2010,(25):13812-13813,13844
对衡阳水稻病虫害特点及其与气象相关性进行研究,结果表明,衡阳虫害发生面积是病害的近4倍,而病害的危害严重程度是虫害的2倍以上;虫害与病害所造成的减产损失分别为57.83%和42.17%;夏季强降水有利于病虫害的发生;随着气候变暖,低温天气对当地虫害越冬的抑制作用在减弱,而对迁徙性害虫的影响微乎其微;高温高湿天气有利于纹枯病的发生和蔓延,中、晚稻破口至抽穗期如遇高温干旱天气,则不利于稻曲病的发生。  相似文献   
90.
中国柞树主要害虫名录(Ⅱ)   总被引:3,自引:3,他引:0  
记述了我国有关鳞翅目(Lepidoptera)钩蛾科(Drepanidae)、尺蛾科(Geometridae)、蓑蛾科(Psychidae)、鹿蛾科(Amati-dae)、枯叶蛾科(Lasiocampidae)、家蚕蛾科(Bombycidae)、大蚕蛾科(Saturniidae)、天蛾科(Sphingoidae)共8个科的柞树主要害虫80种,分别介绍了害虫的中文名称、学名、寄主种类及主要分布区域,为有效控制尺蛾类、枯叶蛾类等柞树主要害虫的发生与危害提供相关的基础信息。  相似文献   
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