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福建省马尾松毛虫灾区区划及其应用 总被引:14,自引:0,他引:14
根据区划理论,应用现代数学方法和计算方法,将福建省马尾松毛虫灾区分为3个区和3个危险程度等级。并按照不同的危险程度等级区域,分别建立了发生面积预测预报模型。经检验。该模型具有较高的精度,可以推广应用。 相似文献
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马尾松毛虫防治指标的研究 总被引:4,自引:0,他引:4
<正>1983~1985年,在江苏省溧水林场对马尾松毛虫室内外取食针叶量、自然虫害和人工剪叶模拟虫害以及各种防治方法的效益等进行了测定和调查。结果表明,松毛虫自然为害与人工剪叶模拟处理对树木生长量的影响是趋于一致的。稂据松树损失针叶量与树木生长损失量的关系,提出了该地区马尾松毛虫的防治指标。 相似文献
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钱范俊 《南京林业大学学报(自然科学版)》1987,30(4):32
<正>黑足凹眼姬蜂是马尾松毛虫幼虫重要的寄生性天敌,在江苏、安徽两省,对马尾松毛虫幼虫的平均寄生率为3.4~50%。该蜂在南京一年发生5代,以幼虫在3~4龄越冬代马尾松毛虫幼虫体内越冬。卵~幼虫期28d,蛹期10~20d,成虫在白天交尾、产卵。成虫寿命2.8~13.6d。无趋光性。雌蜂的平均怀卵量67~207。黑足凹眼姬蜂的茧蛹重寄生天敌有8种,平均重寄生率27.9%,最高重寄生率29.5%(越冬代),其中以次生大腿小蜂为主。 相似文献
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<正>通过8代马尾松毛虫(Dendrolimus punctatus Walker)幼虫室内饲养和野外调查,明确了该虫在宁溧山区一年发生2~3代,以2代为主,幼虫一生为害针叶量接近3000cm,折合鲜重13.4g,干重5.04g。不同性别的幼虫取食量和排粪量均有显著差异,末龄幼虫为害量占总为害量的70%以上。幼龄林上的幼虫越冬期大都在梢头针叶丛中。 相似文献
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《Journal of Natural History》2012,46(21):2789-2801
We studied the age structure and the growth of a breeding population of parsley frogs, Pelodytes punctatus, from a pond system in northern Spain using skeletochronological methods. This population lives in an upland area with marked seasonal differences characterized by long, cold winters and dry summers. We assessed, using the mark–recapture method, the annual periodicity of bone growth marks. Only one line of arrested growth is laid down per winter, showing, in general, a well-defined histological structure. Females are larger than males with 43.31 and 36.32?mm average body length, respectively. This sexual dimorphism in body length increases with age. Males and females reach sexual maturity when they are 1 year old. The oldest males were 8 years old while the females were 2 years older. Growth curves for both sexes were constructed based on body size and the number of lines of arrested growth found in bone sections. The growth rate of males declined abruptly after the first year. Females delayed reproduction and continued to grow at a high rate for 2 years longer than males, thus reaching a higher asymptotic size. 相似文献
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林区水面灯诱昆虫及虫体可用性研究 总被引:3,自引:1,他引:3
自1986年起,在宁溧丘陵林区水面设置诱虫灯网,进行了马尾松毛虫、竹螟、栎舟蛾及杨树舟蛾等多种森林害虫的诱集杀灭和虫体饲鱼研究。松毛虫成虫趋光飞行可达1100 m,扑灯落水雌蛾含有效卵82.3粒/雌蛾,羽化期每灯每夜诱虫5.10kg。对趋光落水昆虫体的蛋白质、脂肪、氨基酸和微量元素含量也做了测定。 相似文献
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LI Gu WU Zhenbin CHENG Shuiping LIANG Wei HE Feng FU Guiping ZHONG Fei 《武汉大学学报:自然科学英文版》2007,12(6):1131-1135
A group of constructed wetlands (CWs) were applied to the recirculating aquaculture system. This study assessed the performance of CWs in treating the aquaculture wastewater, examined the water quality condition of aquaculture ponds and the growth and the survival rate of "target" species (Ictalurus punctatus and Megalobrama amblycephala). The results showed that CWs were effective on reducing the concentrations of 5-day biochemical oxygen demand (BOD5, at 70.5%), total suspended solids (TSS, at 81.9%), chlorophyll a (Chl-a, at 91.9%), ammonium (NH4^+, at 61.5%) and nitrate nitrogen (NOa-N, at 68.0%). Effect of CWs on phosphate (PO43 -P) removal was relatively lower (at 20.0%). The concentrations of BODs, TSS, Chl-a, NH4^+ and TN, TP in the recirculating culture pond were significantly lower than that in the control pond( p〈0.05 ). CWs could help to increase total yield, survival rate of the "target" species and significantly decrease feed conversion ratio ( p〈0.05 ). 相似文献
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DpNPV多角体蛋白拉曼光谱的研究 总被引:2,自引:0,他引:2
研究了马尾松毛虫核型多角体病毒多角体蛋白的拉曼光谱。结果表明,DpNPV多角体蛋白的二级结构主要为α螺旋和无规卷曲,后者含有大量的β回析,多角体蛋白的侧链C-C-S-S-C-C-构型为反式-扭曲-反式。 相似文献
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报道了质型多角体病毒(CPV复合剂)对马尾松毛虫防治效果的试验研究,筛选出菌毒复合剂Ⅰ、Ⅱ号防治效果最佳,林间虫口减退率达76%,蛹期虫口减退率98%,公顷用量Ⅰ号1200亿PIB,Ⅱ号2400亿PIB. 相似文献