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71.
对进口木材和宁波本地木材上的小蠹虫种类进行了调查记载,并对它们的危险性作了初步分析。获得的小蠹虫共有55种,其中从国外进口材上获得49种。主要来自原苏联,计27种。有12种小蠹虫被认为有很大危险性,尤其是来自美国的黄杉大小蠹,在我国尚未见有分布报道。检疫工作者必须予以密切关注。 相似文献
72.
Perennial ryegrass (Lolium perenne L.) infected with a novel endophyte (AR37 or AR1), Wild‐type endophyte or no endophyte (Nil) was sown with white clover (Trifolium repens L.) in autumn 2005. The pastures were rotationally grazed by dairy cows from 2005–2009. Annual dry matter (DM) yield did not differ but AR37 pastures had a higher ryegrass tiller density, especially after the 2008 summer drought (+130%), and less white clover than did AR1 pastures. Concentrations of alkaloids produced by the Wild‐type association (lolitrem B, ergovaline) followed the same seasonal trends as did the AR37 alkaloids (epoxy‐janthitrems) but summer drought reduced concentrations of lolitrem B and epoxy‐janthitrems to less than half the mid‐summer (February) peak concentrations in the other years. Insect pests were monitored annually between 2006 and 2009. Tiller damage by Argentine stem weevil (Listronotus bonariensis (Kuschel)) was significantly reduced by all endophyte treatments. African black beetle (Heteronychus arator (F.)) populations in soil samples increased during the experiment with Nil > AR1 > Wild‐type = AR37. Root aphid (Aploneura lentisci (Pass.)) infestations followed the pattern AR1 > Nil > Wild‐type = AR37. A lower pest pressure from all insect pests in AR37 pastures is likely to have contributed to this treatment having the highest ryegrass tiller densities. 相似文献
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We studied two clones of Eucalypt urograndis hybrid (Eucalyptus grandis 9 E. urophylla), GR283 and GR330, grown in Tumkur district of Karnataka (India), and felled 5–6 years old three trees of each clo... 相似文献
77.
诊断剂量法在黄曲条跳甲抗性监测中的应用 总被引:2,自引:1,他引:2
利用诊断剂量法测定的毒死蜱、丁硫克百威、氯氰菊酯3种杀虫剂的敏感个体与抗性个体诊断剂量分别为40和600mg.L-1、50和800 mg.L-1、63和1000 mg.L-1.根据诊断剂量,利用滤纸药膜法测定4个菜区黄曲条跳甲成虫的抗性个体频率,并与点滴法、浸叶法测定结果进行比较分析.结果表明利用诊断剂量法确定的平坡诊断剂量监测田间种群的药剂敏感性,基本上能够反映黄曲条跳甲田间种群的抗药性水平.因此,诊断剂量法也是一种可供选用的害虫抗性监测方法. 相似文献
78.
Rinat Ismagilovich Ibragimov ;Ildar Salimyanovich Mardanshin ;Galina Vasilyevna Benkovskaya ;Maksim Borisovich Udalov ;Irina Andreevna Shpirnaya ;Vyacheslav Olegovich Tsvetkov 《农业科学与技术》2014,(4):331-341
In field and laboratory conditions the reproductive potential (survival at different stages of development) of the Colorado potato beetle has been measured, the dependence of the parameters of insects fertility on varietal features of the feed has been investigated, the food activity of the representatives of insects from four areas of the Southern Urals has been measured, the intensity and time of hypersensitivity reactions on potato leaves has been defined. In laboratory experiments, the level of activity of hydrolytic enzymes in insects and the level of activity of these enzymes inhibitors in the leaves of three potato varieties differing in their resistance to the Colorado potato beetle have been determined. The results show that the insects-representatives of different samples have different food activity in relation to different potato varieties. High mortality rates were revealed at feeding with leaves of potato of the Bashkir variety characterized by a high level of hydrolases inhibitors and relatively rapid development of necrotic reactions after the appearance of eggs laying on the leaves. We suppose that the neerogenetic barrier appearing in the form of necrosis is the major cause of the fetal mortality of insects. The level of the content of inhibitors inactivating larvae digestive enzymes affects the survival of insects at postembryonic stages. The speed of the necrosis emergence, the level of activity of digestive enzymes inhibitors in potato can be considered as criteria for the selection of breeding material for resistance to the Colorado potato beetle. 相似文献
79.
橡胶小蠹虫为害重,防治困难。为了探索更加高效的田间防治方法,本研究通过将“牛皮纸+粘虫胶+诱集剂”组配,研究集成了一种橡胶小蠹虫粘捕装置,对其诱捕参数(粘捕装置材质、诱集剂药袋悬挂数量、药液暴露面积以及粘捕装置的间距、悬挂高度)进行了筛选,并与常规诱捕器在重量、成本和诱捕效果方面进行比较。结果表明,在月桂烯、2-甲基-3-丁烯-2-醇、S-(-)-柠檬烯、莰烯、顺式-马鞭草烯醇5种诱集剂的诱集下,自制粘捕带对橡胶小蠹虫的粘捕总数分别为:554、445、341、381、367头;普通粘虫带对橡胶小蠹虫的粘捕总数分别为:260、230、179、202、199头。其中月桂烯、2-甲基-3-丁烯-2-醇、S-(-)-柠檬烯,自制粘捕带的粘捕数量均显著高于普通粘虫带,表现出较好的粘捕效果。采用挂袋法的最佳药袋数为2袋,诱集剂的最佳药液暴露面积为6.6 mm2,粘捕装置的最佳相互间距为50 m,最佳悬挂高度建议在2.5 m。自制粘捕装置在重量、成本以及诱集数量上均优于常规诱捕器,对橡胶小蠹虫防控具有高效成本低、环保可降解、简单易操作等特点。 相似文献
80.
新防腐剂TWP橡胶木防腐试验 总被引:3,自引:0,他引:3
TWP防腐剂对木腐菌的毒性剂量为2.2—3.2kg/m~3,毒杀双钩异翅长蠹初龄幼虫的剂量为1.0kg/m~3,抑制蓝变菌和霉菌的毒性浓度分别为1%及1.5—2.0%,对雄性小鼠口服半致死剂量(LD_(50))为1301mg/kg,使用时对人、畜和环境比较安全,并保持木材原有色泽。生产性应用试验结果表明,橡胶木生材用2.0—2.5%TWP,满细胞法或振荡加压法处理,净药保持量4±0.7kg/m~3,防腐效果相当干硼酚合剂12kg/m~3,并优于进口防腐剂。 相似文献