共查询到19条相似文献,搜索用时 46 毫秒
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苏特灵Bt生物杀虫剂防治春尺蛾的试验 总被引:2,自引:0,他引:2
应用苏特灵Bt生物杀虫剂防治春尺蛾,其毒力效价≥8000IU/mg,800倍液防治春尺蛾,室内72h校正杀虫率97.0%,林间72h校正杀虫率96.8%,持效期14d,杀虫率78.7%,是理想的除治春尺蛾的生物杀虫剂。 相似文献
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用V-Bt-Ⅱ型生物复合病毒杀虫剂进行赤松毛虫Dendrolimusspeiabilis防治试验,菌剂用量375g/hm^2,750g/hm^2,1125g/hm^2,1500g/hm^2七天后赤松毛虫死亡率分别96.77%,96.69%,99.31%,100%。 相似文献
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复合生物杀虫剂防治马尾松毛虫研究 总被引:1,自引:1,他引:1
用白僵菌、千胜Bt、25%灭幼脲Ⅲ号和1.8%阿维菌素等4种生物杀虫剂的单一药剂和复合生物杀虫剂对马尾松毛虫进行室内毒力测定.结果表明,单一药剂以阿维菌素的毒力效果最佳,而复合生物杀虫剂以阿维菌素4000倍液+千胜Bt2 000倍液+灭幼脲Ⅲ号8 000倍液+白僵菌1.3×105n/ml为最佳组合,毒力效果达90%以上.应用该复合剂防治不同世代的松毛虫,以第1代的效果最佳,迭93.3%,而越冬代仅为73.5%,用其防治越冬代松毛虫幼虫应选择11月之前. 相似文献
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使用不同剂型,不同用量的苏力精防治1,2代马尾松毛虫幼虫试验结果表明,1200ml/hm^2悬浮剂防治效果90.1%-90.4%;750g/hm^2可湿性粉剂防治效果95.0%-96.4%,1875g/hm^2粉剂喷粉防治效果79.2%-86.5%,而且残存害虫化蛹后继续死亡,成虫产卵量显著减少,对松毛虫天敌无显著不良影响。 相似文献
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Stand Density Control Diagrams for Scots pine and Austrian black pine plantations in Bulgaria 总被引:1,自引:0,他引:1
Stand Density Control Diagram (SDCD) is a stand-level mathematical model, which describes the relationships between yield,
density and mortality throughout all stages of stand development. The SDCD is primarily used to derive density control schedules
by management objectives. The main objectives of the present study are to define a modified model of SDCD for application
to Scots pine (Pinus sylvestris L.) and Austrian black pine (Pinus nigra Arn.) plantations in Bulgaria, to examine the fitness of the model with representative experimental data sets from plantations
of both species and to present a way of direct application of the SDCDs for practical purposes. The constructed SDCDs characterize
the spatial-temporal dynamics of the pine plantations in a broad range of densities, forest sites and growth stages from 4
to 26 (28) m of dominant height class. The full density lines were fixed with self-thinning exponents α = 1.69 and α = 1.75
for Scots pine and Austrian black pine, respectively, and the trajectories of natural thinning for 23 initial densities (444-40000/ha)
were determined. A direct way for application of the SDCDs to the plantation management was designed to estimate the optimal
initial densities for the maximum attainable final yield and large-size wood production by self-thinning stands. 相似文献
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马尾松水保林的密度管理 总被引:1,自引:0,他引:1
该文通过研究马尾松水保林各组份生物量的密度效应,从生物产量的角度出发,分析马尾松水保林的密度结构与水保功能之间的关系,提出了马尾松水保林的最适经营密度。 相似文献
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松毛虫是祁连山林区主要林业有害生物,主要危害青海云杉,不仅影响造林更新,降低林分质量,还严重影响了林业生产的发展和生态环境的治理。2006—2008年在山丹马场自然保护站林区对松毛虫的生活习性进行了观察,基本查清了该虫的生活习性,总结出有效的防治办法,目的是使树木能够正常生长或最大程度减少为害损失。 相似文献
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三种生物农药防治灰斑古毒蛾林间试验 总被引:4,自引:1,他引:3
利用生绿Bt杀虫剂、1.8%阿维菌素、1.2%苦.烟乳油3种生物农药对灰斑古毒蛾OrgyiaericaeGermar 2~4龄幼虫进行了林间防治试验。结果表明,生绿Bt杀虫剂525 g/hm2对灰斑古毒蛾的防治效果为82.46%,最为经济有效;1.8%阿维菌素450 mL/hm2~150 mL/hm2对灰斑古毒蛾的防治效果在80.04%~100%之间,其中1.8%阿维菌素300 mL/hm2的防治效果最好。1.2%苦.烟乳油3种浓度的防治效果均为100%。 相似文献
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松突圆蚧Hemiberlesia pitysophila Takagi是重要的检疫性有害生物,严重影响松树生长.纵带间伐套种相思类阔叶树改变了沿海黑松林的生境条件,增强林木抗性,阻隔了松突圆蚧的传播途径.使林间的松突圆蚧虫口密度由间伐前(2002年)的4.58头/针束,降低到次年的0.82头/结束,虫口减退率为82%,平均防治效果达85.68%,到2005年平均防治效果达94.23%. 相似文献
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Only recently have efforts begun to address how management might prepare currently healthy forests to affect the outcome of
invasion by established non-native pests. Cronartium ribicola, the fungus that causes the disease white pine blister rust (WPBR), is among the introductions into North America where containment
and eradication have failed; the disease continues to spread. Ecosystem function is impaired by high rust-caused mortality
in mature five-needle white pine forests. This paper evaluates five proactive management options to mitigate the development
of impacts caused by white pine blister rust in threatened remote high-elevation five-needle pine ecosystems of western North
America. They are: reducing pest populations; managing forest composition; improving host vigor; introducing resistant stock
with artificial regeneration; and diversifying age class structure to affect the natural selection process for resistance.
Proactive intervention to manage and facilitate evolutionary change in the host species may sustain host populations and ecosystem
function during pathogen naturalization. 相似文献