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41.
椰子织蛾是一种近期入侵我国的危险性有害生物。运用国际植物检疫措施实施标准(ISPM)的有害生物风险分析(PRA)程序,建立椰子织蛾传入风险分析评估模型,采用定性分析和多指标综合评估相结合的方法进行分析。结果显示,福建省分布情况,风险值为3;潜在的经济危害性,风险值为2.0;寄主植物的经济重要性,风险值为3;传播扩散的可能性,风险值为1.78;风险管理难度,风险值为2。椰子织蛾的综合风险性值为2.3,符合高度危险的外来有害生物条件,已在我国海南、广东、广西等地区定殖,对福建省的棕榈科植物威胁很大,建议将其列入福建省补充林业检疫性有害生物名单,加强检疫管理、监测和控制工作,严防其传播和扩散危害。 相似文献
42.
昆虫生长调节剂的抗性治理对策 总被引:4,自引:0,他引:4
综述了昆虫生长调节剂的发展概况,昆虫生长调节剂———保幼激素类似物、蜕皮激素类似物、几丁质合成抑制剂(含苯甲酰基脲类除虫剂、噻二嗪类、三嗪(嘧啶)胺类等品种)、四环三萜类化合物的应用研究情况以及农业害虫对昆虫生长调节剂的抗性机理,对不同的昆虫生长调节剂,其抗性机理不同.对于抗几丁质抑制剂,可能是几丁质合成酶受到保护,使抑制剂的穿透率降低;保幼激素类似物因双键或环氧等易被多功能氧化酶氧化降解.依据抗性机理,需加强抗性监测,从而更好地进行抗性治理. 相似文献
43.
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
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毛白杨树皮内含物对光肩星天牛抗性的探讨 总被引:18,自引:3,他引:18
毛白杨树皮内含物对光肩星天牛抗性的探讨王蕤,巨关升,秦锡祥(中国林业科学研究院林业研究所北京100091)关键词杨树,抗性,酚酸,酚甙光启星天牛(AnoplophoraslabripennisMotsh.)对杨树危害严重,受害的树种多,涉及的地域广,... 相似文献
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48.
D. Shtienberg Y. Elad Ariela Niv Y. Nitzani B. Kirshner 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(8):753-763
The most serious symptom of Botrytis cinerea in tomatoes grown in greenhouses is stem rotting. Lesions on the stem may result from direct infection or from progression of the rot along infected leaves, until infection approaches the stem. In a set of experiments conducted in commercial greenhouses, an experimental greenhouse and growth chambers, the significance of the two types of stem infections was studied. In non-heated greenhouses most of the stem lesions originated from progression of the pathogen along infected petioles. The rate at which B. cinerea had progressed on infected petioles was 0.3–0.5 cm/day, an average of ca. 6 weeks was needed for a leaf infection to approach the stem. Application of Trichoderma harzianum T39 extended this time by 1–2 weeks and application of chemical fungicides by 3 weeks. Influence of the environment on the progression of B. cinerea along infected petioles was then determined. Within range of 5–30 °C, the higher the temperature, the more rapid was the rate of disease progression. The fungus progressed more rapidly on tomato petioles incubated at high vapour pressure deficit (VPD) rather than at low VPD. The source-sink relationship of the plant governed the rate of B. cinerea progression along the petioles as well: it was more rapid when the source was restricted (by shading) and slower when the sink was restricted (by removal of flowers and small fruits). The possibility that sanitation of infected leaflets would reduce the incidence of stem rotting was examined in two experiments. In plots not treated with a fungicide, the sanitation treatment substantially decreased the incidence of stem lesions and this treatment was as effective as weekly application of chemical fungicides. 相似文献
49.
试论昆虫资源学的理论基础 总被引:3,自引:0,他引:3
昆虫资源学是一门既古老又新兴的学科。本文从生物多样性的观点出发,论证了占整个动物界五分之四的昆虫物种多样性,以及昆虫物种多样性的物质表现-丰富的昆虫资源。以生物多样性理论作为昆虫资源学的理论基础,为这一学科注入丰富的内涵和广博的外延。 相似文献
50.
Integrated pest management in field vegetable crops in northern Europe — with focus on two key pests
Improvements in (1) insecticide application, (2) supervised control, and (3) pest forecasting systems have each helped to reduce considerably the amounts of insecticides required to control fly, caterpillar and aphid infestations in vegetable crops in northern Europe. By growing plants that are partially resistant to certain major pests, it is now possible to apply even less insecticide than the dose recommended for the crop. In crops where only small amounts of insecticides are applied, natural predators should prevent large increases in pest insect populations and natural parasitoids should reduce the numbers of pest insects entering subsequent generations. The possible impact of introducing transgenic plants and the use of physical (crop covers), cultural (crop rotation, undersowing) and microbial (e.g. fungi, bacteria and nematodes) methods of control are also discussed. The withdrawal of certain insecticides, as a result of environmental and commercial pressures, means that some crops may soon be without appropriate insecticides for controlling one or more of the major pest species. Whether such systems will be sustainable, remains to be seen. 相似文献