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测定分析了叶甲科(Chrysomelidae)15种昆虫mtDNA_Cyt b基因部分序列,结果显示,在获得的390 bp序列中,198个核苷酸位点为多态性位点(约占50.8%),序列间碱基差异平均值为18.9%,A T含量为72.7%,碱基转换呈现明显的TC偏向性,颠换主要以TA为主,转换/颠换(R)值为0.8。依据分子数据建立了该15种昆虫的系统发育关系,结果表明:跳甲亚科(Alticinae)和叶甲亚科(Chrysomelinae)的亲缘关系较近,萤叶甲亚科(Galerucinae)与前两者的关系较远。萤叶甲亚科中瓢萤叶甲为最早分化的类群,长跗萤叶甲属(Monolepta)、凹翅萤叶甲属(Paleosepharia)、长刺萤叶甲属(Atrachya)能形成姊妹群。克萤叶甲属(Cneorane)和守瓜属(Aulacophora)的亲缘关系较近。基于蛋白质序列构建的系统树的置信值高于核苷酸序列建立的系统发育树。 相似文献
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曾涛 《华南农业大学学报》2001,22(1):49-50
描述了小崎齿瓢虫属(Afidentula)和长崎齿瓢虫属(Afissula)各一种幼虫形态,幼虫标本保存于南京农业大学昆虫标本室。 相似文献
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本文记录了采自山东泰山的瓢虫科昆虫30种,其中属于山东省的新记录7种。 相似文献
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The ecological effects of planting exotic Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] in Central Europe are still poorly understood. The aim of this study was to answer the question of whether Douglas-fir affects tree specific arthropod communities in different mature forest types (Douglas-fir, spruce and beech dominated) in Southern Germany. Therefore, arthropod communities of stem and tree crown strata of Douglas-fir and spruce (Picea abies L.) were sampled in the years 1999–2001 using arboreal photo-eclectors and flight interception traps. Statistical analysis was conducted for all species and focused on conifer specialists at three levels: (1) species diversity, (2) guild structure and (3) community structure. Within the stem stratum, species diversity was significantly higher on spruce than on Douglas-fir independent of year and stand composition. This could not be explained by a single feeding guild, rather by species changing strata during the vegetation period. In contrast, species diversity in tree crowns was approximately the same for both conifer species. However, communities in Douglas-fir crowns were conspicuously different from those in spruce crowns, especially in the Douglas-fir dominated stand type. While zoophagous insects exhibited higher activity on Douglas-fir in 2000, xylophagous beetles were more abundant on spruce in 2001. In European beech stands with widely spaced Douglas-fir trees, the site specific and broad-leaved tree related fauna might be maintained. In addition, Douglas-fir with its resource of Adelges cooleyi and crowns that overtop the broad-leaved tree canopy, offer additional resources for several aphidophagous and thermophile species. 相似文献
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[目的]探讨鞘翅目昆虫多样性变化对不同生境类型的生态反应。[方法]选取哈尔滨市不同生境区域中的样地,分析鞘翅目昆虫的群落结构及其多样性。[结果]共获得鞘翅目昆虫标本3 215个,隶属鞘翅目55科120属233种,其中以小蠹科(Scolytidae)等为优势类群。东北林业大学林场多样性指数最高,其次是哈尔滨植物园,帽儿山实验林场老山实验站最低。帽儿山实验林场老山实验站物种丰富度和优势度指数最高,其次是东北林业大学林场,哈尔滨植物园最低。不同生境类型的鞘翅目昆虫群落多样性的时间动态不同,哈尔滨植物园的鞘翅目昆虫群落多样性指数随时间的波动最小,帽儿山实验林场老山实验站的物种数和优势度指数波动较大。不同生境区域鞘翅目昆虫相似性系数为中等不相似或极不相似水平,说明各生境类型的鞘翅目昆虫栖息地空间异质性较大,导致鞘翅目昆虫群落间相似性程度较低。[结论]该研究可为城市生态可持续发展、森林生态系统的多样性保护提供科学依据和理论基础。 相似文献
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[目的]为有效实施烟草储藏害虫综合治理、确保烟草及其制品品质提供新方法。[方法]研究不同温度(25、35、45、55、60、65℃)下处理不同时间(60、75、90、105、120 s)对烟草甲成虫、蛹、幼虫和卵的致死作用。[结果]结果表明,不同处理温度、不同处理时间对烟草甲各虫态的致死作用效果差异显著。在处理温度为25、35和45℃时,该试验各个处理时间对烟草甲各虫态均无致死作用,而在处理温度为55℃以上时对烟草甲各虫态均具有较强的致死作用。在处理温度为60℃时,对烟草甲成虫、蛹、幼虫和卵达到100%致死作用的最短处理时间分别为90、120、75和75 s。[结论]高温处理可以作为一种有效的害虫防治方式运用到储烟害虫综合治理当中。 相似文献
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Long term data to estimate population trends among species are generally lacking. However, Natural History Collections (NHCs) can provide such information, but may suffer from biases due to varying sampling effort. To analyze population trends and range-abundance dynamics of Swedish longhorn beetles (Coleoptera: Cerambycidae), we used collections of 108 species stretching over 100 years. We controlled for varying sampling effort by using the total number of database records as a reference for non-red-listed species. Because the general frequency of red-listed species increased over time, a separate estimate of sampling effort was used for that group. We observed large interspecific variation in population changes, from declines of 60% to several hundred percent increases. Most species showed stable or increasing ranges, whereas few seemed to decline in range. Among increasing species, rare species seemed to expand their range more than common species did, but this pattern was not observed in declining species. Historically, rare species did not seem to be at larger risk of local extinction, and population declines were mostly due to lower population density and not loss of sub-populations. We also evaluated the species’ declines under IUCN red-list criterion A, and four currently not red-listed species meet the suggested threshold for Near Threatened (NT). The results also suggested that species’ declines may be overlooked if estimated only from changes in species range. 相似文献
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