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电动树干注射机逆变电源浅析李绍，吕小红，赵瑞良，刘随存（太原工业大学）（山西省林业科学研究所）近年来，省内外在对光肩星天牛等蛀干害虫的防治中，出现了一种在树干基部打孔注药的新方法。这种方法，较之树干喷药和树冠喷药，具有用药少、防治效果好、不污染环境等... 相似文献
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用毒环毒绳防治杜仲夜蛾李建林，吕永财（略阳县森防站）利用杜仲夜蛾３龄以后幼虫黎明前下树潜伏，傍晚上树取食的习性，以及其老熟幼虫下树入土化蛹的习性，在树干上涂刷毒环或绑扎毒绳，以阻杀幼虫。该法不仅能克服全树喷药带来的污染，而且还具有省时省工、操作简单、... 相似文献
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对8个品种的芍药切花进行瓶插观测,逐日记录其开花指数、花径变化及衰老征兆。结果表明:不同品种其开花指数、花径变化及衰老征兆与瓶插寿命之间存在着一定的联系,落瓣是其衰老的主导因素。 相似文献
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福建山樱花种子发育观察与育苗技术研究 总被引：6，自引：2，他引：4
对福建山樱花花期、种子发育过程进行多年的定点不定期观察,开展了福建山樱花种子的不同催芽条件和不同播种方法的育苗试验。研究结果表明:在福建省南平市,福建山樱花4月20日左右胚珠发育成熟,采种期为4月25日左右;冷藏至翌年春播种,种子发芽率达96.8%;撒播芽苗移栽的播种方法最好,1年生苗木平均高1.72 m、平均地径1.03 cm;福建山樱花生长较迅速,3年生平均高可达3.6 m、平均地径可达3.8 cm。 相似文献
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核桃细菌性黑斑病无公害防治技术研究 总被引：1，自引：0，他引：1
2003～2006年,在宾川县帽角山、李子园核桃产区进行了核桃细菌性黑斑病防治技术试验,结果认为,发芽前、展叶后、花前花后、幼果期、果实速长期用80%久生M-100可湿性粉剂400倍、24%施达康可溶性粉剂1500倍、碘1% AS 1000倍、78%科博400倍、50%氯溴异氰尿酸1500倍、72%农用链霉素可湿性粉剂4000倍稀释液喷雾,并辅以清除感病枝条、病斑、病芽、病果、病叶、感病叶痕、树苗病组织、茎的老病斑以及合理水肥,能有效防控核桃细菌性黑斑病,迅速恢复核桃产量. 相似文献
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D. A. Sepúlveda F. Zepeda-Paulo C. C. Ramírez B. Lavandero C. C. Figueroa 《Journal of pest science》2017,90(2):649-658
Inbreeding frequently reduces the fitness of organisms, but little is known about how this phenomenon can affect the biological control. Host fidelity provides an adaptive advantage to aphid parasitoids, allowing females to find their aphid host more quickly in heterogeneous environments. This trait is mediated by the learning of signals, mainly chemical cues emitted from the host in which parasitoids developed (natal). This article is aimed at studying whether host fidelity can be altered after many generations of inbreeding reproduction in caged laboratory populations, for which host preference and fitness parameters were measured in the parasitoid wasp Aphidius ervi. Also, the effect of the natal/non-natal hosts was studied, using parasitoids originated from the pea aphid (Acyrthosiphon pisum) and the grain aphid (Sitobion avenae). We observed a loss of host fidelity in the studied A. ervi populations, irrespective of their natal aphid host, which contrasts with previous reports showing preference for natal hosts in outbred laboratory populations. The loss of host fidelity is discussed in terms of the origin of populations; the sex ratio was strongly biased toward males and long-time maintenance under laboratory conditions. Our results highlight the need for controlling the genetic diversity of caged parasitoids before they are released into fields, as a long period of inbreeding could negatively affect the biological control. 相似文献
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Dr. S. C. Chafe 《Wood Science and Technology》1993,27(3):205-217
Summary Preboiling and drying wood samples of Eucalyptus regnans has shown that while in the heartwood shrinkage before reconditioning increased as a linear function of the logarithm of boiling time (BL), in the sapwood it decreased. These changes were interpreted as reflecting changes in green permeability through extractive modification which, for the sapwood, were sufficient to overcome any weakening of the cell walls through heat effects; in the heartwood, however, cell wall degradation apparently overshadowed any collateral increase in permeability, thus causing an increase in collapse.Shrinkage after reconditioning described a cubic function with respect to BL and showed an overall reduction which was greatest after 16 minutes boiling time. Correspondingly, recoverable collapse was greatly increased through preboiling; it was shown that per cent collapse recovery in the heartwood could be increased by more than one third that of controls by preboiling for 8 minutes. The possibilities for industry application are considered.Moisture content after reconditioning (Mr) was greatest after about two minutes preboiling, then declined to be less than the control after 16 minutes. Change in shrinkage after reconditioning and collapse were shown to be significantly related to change in Mr. It was suggested that while Mr may reflect relative permeabilities after reconditioning, this may not apply to permeability in the green condition.Additional parameters derived from the data, viz. the intersection point, unit shrinkage, the R-ratio, collapse-free shrinkage, total collapse and residual collapse described mostly significant, cubic relationships with the logarithm of the boiling time. Generally, the major inflection point of regression curves occurred after 8 or 16 minutes boiling.The author expresses his appreciation to Margaret Walker for technical assistance 相似文献
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加勒比松及其杂种的无性繁殖 总被引：12，自引：1，他引：11
加勒比松自引进我国已有近40年的历史,表现出速生丰产、产脂高、适应性强等优良特性,但加勒比松及杂种良种供应量明显不足。主要原因是引进的加勒比松开花结实晚,种子产量低;另一原因是进口的杂交良种价格昂贵。针对以上问题,文中指出除继续大力开发我国自己的加勒比松与湿地松种间和加勒比松种内杂交技术外,还应加强研究加勒比松及其杂交种的无性繁殖技术。通过回顾加勒比松的无性繁殖技术的进展状况,重点指出要学习澳大利亚等国的先进的扦插繁殖技术,形成一套成熟的加勒比松的无性繁殖技术。同时还应大力发展加勒比松及杂种体细胞胚胎发生技术。 相似文献
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套袋栽培对高节竹笋品质的影响 总被引：2，自引：0，他引：2
选择生长良好、均匀的高节竹林作为样地,在出笋高峰期标记即将出土的竹笋320株,其中160株用0.3mm厚(共3层,每层0.1mm)的黑色塑料袋遮光,另160株作为对照。随着竹笋的生长,依次从遮光笋及对照笋中采收地上部分高度接近5、10、15、20、25、30、35cm的笋,待预处理后作为样品进行营养成分的分析。结果表明,在竹笋地上部分高度10～30cm范围内,套袋能降低竹笋中单宁、维生素C、粗蛋白的含量;套袋栽培的竹笋中粗纤维含量比自然生长的竹笋中的粗纤维含量约低10%以上,氨基酸总量也高于自然生长的竹笋。 相似文献
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Wolfgang Stein 《Journal of pest science》1970,43(7):104-106
Summary Spraying in an apple orchard with Folidol-Öl (mineral oil + parathion) resulted in a total mortality of the curculionid beetles in a meadow beneath the trees.The recovery of this curculionid fauna was studied. It was shown that it depends particularly on the dispersal and migrating behaviour of the single species. So it may happen that one species is absent for nearly one year in such a biotop, if its migration or dispersal phase had occurred just before the application. On the other hand, some species may be found again shortly after the effect of the insecticide ceased, if their migration or dispersal phase falls into this period.In Fig. 1 the results of these investigations are shown for the most important curculionids. While some species with a migration phase in spring and early summer could be found already a few weeks after application(Apion assimile, A. apricans, A. flavipes andPhytonomus nigrirostris), Sitona-beetles andApion virens appeared only 3–4 months later, as a result of the fact that they have their dispersal phase in late summer after hatching of the new generation. 相似文献
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