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We have described the morphological variation of five Western Palaearctic species of Monochamus Dejean, 1821. The variation was assessed using wing measurements. Special emphasis was placed on the differences between Monochamus sartor (F., 1787) and Monochamus urussovii (Fischer-Waldheim, 1805). There was an interesting pattern of variation between the two species. Individuals of M. sartor from the Carpathians differed markedly from individuals of M. urussovii from Siberia, but individuals from north-eastern Poland were intermediate between those two populations. The intermediate individuals were more similar to the Siberian M. urussovii than to the Carpathian M. sartor despite the relatively large geographic distance between north-eastern Poland and Siberia. The occurrence of the intermediate individuals in north-eastern Poland may be the effect of hybridization between M. urussovii and M. sartor, which might have occurred after secondary contact between the two species in the Holocene. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):257-265
The attacks of bark‐ and wood‐boring Coleoptera on broken conifer stems after severe snow‐breakage in early 1988 were studied in autumn 1988 and 1989. The study included twelve stands in the county of Värmland in central Sweden differing in age and edaphic conditions. The tops on the ground as well as the remaining rooted stem stumps of 94 Picea abies and 61 Pinus sylvestris were inspected. The presence of living branches on the stumps strongly influenced the incidence of insect attack. All stumps without branches were attacked during the two‐year period, whereas only a few spruce stumps with more than ten branches and no pine stumps with more than five branches were attacked. On spruce stumps, the most frequently encountered Coleoptera were all scolytids, i.e. the species Pityogenes chalcographus, Hylurgops palliatus, and the genera Polygraphus, Dryocoetes, and Trypodendron. On pine stumps, Tomicus piniperda was the most common species. Most of the spruce tops and virtually all pine tops were attacked during the two‐year period, and most of these attacks occurred during the first summer. P. chalcographus, Dryocoetes, and weevils of the genus Pissodes were the most frequent Coleoptera on spruce tops. On pine tops, the dominant insects belonged to the genera Pissodes and Pityogenes. 相似文献
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Field evaluation of 3‐hydroxy‐2‐hexanone and ethanol as attractants for the cerambycid beetle pest of vineyards,Xylotrechus arvicola 
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天牛科纤维素酶同工酶研究 总被引：8，自引：1，他引：8
用聚丙烯酰胺凝胶等电聚焦电泳方法分析了天牛科两个亚科１８种雌成虫、１２种幼虫消化道中肠组织纤维素酶复合酶中Ｃｘ酶同工酶．Ｃｘ酶同工酶在亚科间、族间差异较大；同族内各属间的酶谱差异也较大；同属内不同种间酶谱较接近，但每种各具其特征酶带，彼此易区分。Ｃｘ酶同工酶用于亲缘关系相近种的分类、鉴定有重要价值，可作为天牛科分子分类的一个有用的辅助手段。文章还就楔天牛族Ｓａｐｅｒｄｉｎｉ的分类系统问题进行了讨沦． 相似文献
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天牛消化纤维素的机制研究 总被引：7，自引：1，他引：7
天牛能否自身消化植物的纤维素,是长期来争论未决的问题,本课题用聚丙烯酰胺凝胶等电聚焦电泳方法着重研究了纤维素酶复合酶中C_X酶在虫体中的来源。对天牛科18种雌成虫、16种雄成虫、12种幼虫消化道C_X酶进行了电泳分离,并根据C_X酶同工酶在不同虫态与不同发育程度间的差异,探讨了天牛科C_X酶的来源,结果证明天牛中肠肠壁细胞能自身分泌C_X酶。 相似文献