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在皖南春季越冬代马尾松毛虫防治时期,于安徽长江以南采用不同治虫策略的5个林场,选立地条件和林分状况类似的马尾松纯林,对节肢动物和虫生真菌群落的调查表明,常年释放白僵菌的林场和长期监测虫情、准确挑治虫源地的林场害虫种数约占群落总种数的50%,个体数约占70%,益害物种数比(Ns/Ps)为0.72~0.83,个体数比(Nn/Pn)为0.44~0.45,多样性指数(H′)波动小,松毛虫虫口≤2.0条·株-1.交替放菌和施药的林场,滥用农药、尤其不治虫的林场,害虫种数约占群落总种数的60%左右,个体数>74%,Ns/Ps0.46~0.54,Nn/Pn0.23~0.34,H′波动大,松毛虫虫口6.0~10.0条·株-1,超过防治指标(5条·株-1).长期的放菌或及时施药挑治利于优化群落结构,增大多样性指数,强化生态控制的力度 相似文献
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During the period of
controlling the overwintering generation Dendrolimus punctatus in similar stands in 5
forestry farms with the different control strategy along the southern shore of Changjiang
River,arthropoda and entomogenous fungi communities were surveyed.The result showed that
comparing the communities of the forestry farms with Beauveria bassiana releasing every
year with that in the forestry farm controlled by insecticides,the species number of pests
were around 50%,the individuals were 70% or so,the ratio of natural enemy to pest species
number (Ns/Ps) was 0.72~0.83,the ratio of natural enemy to pest individuls number
(Nn/Pn) was 0.44~0.45,idexes of diversity (H′) fluctuated little,and population
densities of D.punctatus≤2.0 heads/tree.Within the forestry farms with alternated
releasing of B.bassiana and applying insecticides,overflowed applying insecticides,and
non-controlling forestry farms,the pest species number was around 60%,individual number
was 70% or so,Ns/Ps was 0.46~0.54,Nn/Pn 0.23~0.34 ,H′ fluctuated greatly,and the
population densities of D.punctatus was 6.0~10.0 heads/tree,which was over the control
threshold (5 heads/tree).A long time realesing B.bassiana formulation and selecting
appropriate suppression were beneficial to optimizing community structure. 相似文献
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在皖南春季越冬代马尾松毛虫防治时期,于安徽长江以南采用不同治虫策略的5个林场,选立地条件和林分状况类似的马尾松纯林,对节肢动物和虫生真菌群落的调查表明,常年释放白僵菌的林场和长期监测虫情、准确挑治虫源地的林场害虫种数约占群落总种数的50%,个体数约占70%,益害物种数比(Ns/Ps)为0.72~0.83,个体数比(Nn/Pn)为0.44~0.45,多样性指数(H′)波动小,松毛虫虫口≤2.0条·株-1.交替放菌和施药的林场,滥用农药、尤其不治虫的林场,害虫种数约占群落总种数的60%左右,个体数>74%,Ns/Ps0.46~0.54,Nn/Pn0.23~0.34,H′波动大,松毛虫虫口6.0~10.0条·株-1,超过防治指标(5条·株-1).长期的放菌或及时施药挑治利于优化群落结构,增大多样性指数,强化生态控制的力度 相似文献
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球孢白僵菌对非目标无脊椎动物致病性的研究 总被引:4,自引:1,他引:4
本研究首次提出了大面积、长期放菌后,球孢白僵菌(Beauveriabassiana)对无脊椎动物致病性的评价方法。春季在连日高湿(RH>90%)的马尾松纯林中释放超高剂量孢子粉(每667m 2用量为100g,每g含孢量>1000×10 8),1个月后目标昆虫马尾松毛虫(Dendrolimwspunctatus)感病死亡率达98.2%,对非目标昆虫则影响极小,只在试验区及隔离区内各发现1头螺纹蓑蛾(Claniacrameri)感病虫尸,这表明放菌未影响节肢动物群落结构。此外,还在皖南几种类型白僵菌防治区内共设立9块标准地,1992~1995年每月1次调查非目标无脊椎动物感病种数、个体数及百分率。发现罹病物种数<0.95%,罹病个体数<0.15%。 相似文献
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马尾松毛虫(Dendrolimus puncta-tus Walker)(以下简称松毛虫)的防治,必须以测报为基础。由于目前无法直接对高大林木进行调查,在长江两岸地区,尤其是松毛虫第一、二代,不象越冬代那样可以利用其下树越冬的习性剥树皮调查,加之松毛虫消长变化迅速,所以第一、二代的测报方法是生产上急需解决的一个重要问题。作者结合防治实践,进行了数年研究,取得初步效果,现介绍如下。 相似文献
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马尾松林中的若干次要食叶害虫是马尾松毛虫的寄生或捕食性天敌的转主寄主,从而使马尾松纯林至少有6条比较稳定的食物链和沿着这6条食物链流动的48条能流线。因此,只要合理地实施人工防治,不滥用化学杀虫剂,能够提高马尾松纯林的自然控制能力,有利于控制马尾松毛虫灾害,并达到综合防治多种食叶害虫的良好效果。 相似文献