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1.
本文用图文描述了番禺口岸近3年来从进口原木中截获的8种长蠹科害虫,包括电缆斜坡长蠹Xylopsocus capucinus(Fabricius)、黄足长棒长蠹Xylothrips flavipes(Illiger)、竹蠹Dinoderus minutus(Fabricius)、三胝双棘长蠹Sinoxylon senegalense Karsch、双棘长蠹Sinoxylon anale Lesne、双钩异翅长蠹Heterobostrychus aequalis(Waterhouse)、大竹蠹Bostrychopsis parallela(Lesne)和红艳长蠹Xylothrips religiosus(Boisduval)等重要长蠹成虫的主要形态特征,并编制了分种检索表.  相似文献   

2.
本文综述了我国进境原木上截获的主要害虫类群;总结了目前进境原木害虫的检疫处理技术;重点介绍了斯氏线虫Steinernema sp.对钻蛀性害虫的防治研究,探讨了斯氏线虫在进境原木害虫检疫处理上的应用前景,提出了应用斯氏线虫防治进境原木害虫所存在的问题及今后的研究方向.  相似文献   

3.
本文对2010—2015年全国口岸从美国进境松木中截获的齿小蠹进行了分析,分别对美云杉齿小蠹Ips borealis、美雕齿小蠹I.calligraphus、混点齿小蠹I.confusus、重齿小蠹I.duplicatus、南部松齿小蠹I.grandicollis、蒙大拿齿小蠹I.montanus、似混齿小蠹I.paraconfusus、白云杉齿小蠹I.perturbatus、美松齿小蠹I.pini、平额重齿小蠹I.plastographus、十二齿小蠹I.sexdentatus、云杉八齿小蠹I.typographus 12种昆虫的进境寄主进行统计,对截获频次进行分析对其成虫的主要形态特征进行了描述,编制了分种检索表,对检疫鉴定工作具有指导意义。  相似文献   

4.
Stephen L.Wood和黄复生1986报道(Stephen,1986),将拟鳞小蠹属Pseudoxylechinus定为新属,包括5种。本文介绍1新种云杉拟鳞小蠹Pseudoxylechinus piceae sp.nov.的形态特征及列出该属6种的检索表。属的特征其中触角锤状部近基1/3处有一横向几丁质嵌隔(上述论文未提及)。  相似文献   

5.
根据国际植物检疫措施标准(ISPM)规定的有害生物风险性分析程序,利用相关风险分析模型,从国内分布状况、潜在的危害性、受害寄主的经济重要性、传播和扩散的可能性及风险性管理难度5个方面对几内亚甘蔗象传入扩散风险进行定性、定量分析。结果表明其综合风险值R为2.57,属于高度危险的有害生物。据此提出了3条风险管理对策,以期使风险降低到可接受水平。  相似文献   

6.
园林植物新害虫——黑色枝小蠹的调查   总被引:2,自引:0,他引:2  
新近在贵阳地区发现一种重要的钻蛀性园林植物害虫,为害包括珙桐及木兰科等珍贵树种在内的多种植物,造成大量植物枝条枯死。经鉴定初步定为小蠹科(Scolytidae) Xylosandrus属中的一种X. compactus,异名为Xyleborus morstatti,Xyleborus compactus。文中对其危害特点、形态特征及生物学特性进行了详细描述,并对其防治策略及其它相关问题进行讨论。  相似文献   

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江门海关从冈比亚进境的刺猬紫檀木原木中检出活体长蠹科昆虫.通过显微形态特征的观察和测量,对该虫进行了物种鉴定.经形态特征鉴定,该虫为小楔双棘长蠹.该虫的形态特征与近似种的主要区别:斜面毛被稀疏、不太明显,近缝角处竖立短直;缝侧齿基部不粗糙;斜面侧上缘有3对胝状的痕迹显现.该虫在我国尚无分布记录,为国内口岸首次截获.该虫...  相似文献   

9.
在非洲进口木材中截获的长蠹科害虫的分类   总被引:9,自引:0,他引:9  
陈志粦 《昆虫知识》2003,40(2):154-159
报道了近年来从非洲进口木材检疫中截获的长蠹科 1 4种害虫 ,并分别对细齿叉尾长蠹Xylionadustus、多齿叉尾长蠹X .plurispinis、毛额奸狡长蠹Apatefemoralis、大角胸长蠹Bostrychoplitesmegaceros、长缘缝棘长蠹Xyloperthodesdiscedens、三胝双棘长蠹Sinoxylonsenegalense、红角双棘长蠹S .ruficorne、褐斑木长蠹Xylodectesornatus、多毛碎木长蠹Xyloperthacrinitarsis、棕异翅长蠹Heterobostrychusbrunneus等重要长蠹成虫的主要形态特征进行了描述 ,编制了分种检索表。  相似文献   

10.
1997年春,沙县板栗试验场20hm~2的二年生板栗树开始抽梢展绿,可是还有几百株树却迟迟不见萌芽现绿。我们现场检查发现这些树多已枯死,稍微-推在离地面10-30cmd处的主干即断裂,断裂处均是交错蛀空的虫道、虫室,虫室中有一种甲虫及其幼虫、卵、蛹。把主干纵向剖开,也有众多的虫道、虫室和甲虫的成虫、幼虫、卵、蛹。我们随即对已经萌发抽梢的板栗树进行调查,发现许多树的主干上有数量不等的虫孔,株受害率高达77.6%。该虫的危害特点,是由于成虫蛀空了主干木质部造成水分、养分无法输导,而导致全株枯死。该甲虫…  相似文献   

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ABSTRACT

A phytosociological study of the urban woods of Rome is described. Six syntaxonomical types were identified: 1) Orno-Quercetum ilicis, an edaphic-xerophytic variant of the natural potential vegetation of the city (deciduous Quercus sp. pl. woods); 2) Aquifolio-Fagetum carpinetosum betuli, in the northern slopes of alluvial valleys; 3) Q. suber and Q. pubescens wood, ranked in Quercetalia pubescenti-petraeae order 4) Quercetum ilicis galloprovinciale suberetosum; 5) coppice of Q. cerris and Q. frainetto, which belongs to the Teucrio siculi-Quercion cerridis alliance; 6) mixed mesophile wood of Q. cerris and Ostrya carpinifolia which can be considered a transition between the Doronico-Fagion and the Teucrio siculi-Quercion cerridis alliances. All of these six woody vegetation types are characterised by the large penetration of Mediterranean species belonging to the Quercetea and Quercetalia ilicis and the middle-European ones of the Querco-Fagetea. This mosaic of species exemplifies the bioclimatic characteristics of Rome, which is situated in a Mediterranean transitional region.  相似文献   

13.
蛋白质分形研究现状及展望   总被引:1,自引:0,他引:1  
分形理论是以不规则的复杂性物体为研究对象,描述它们秩序和结构的一种方法。研究发现,蛋白质作为一种生物大分子,在不同层次上表现出一定尺度范围内的分形特征。主要介绍了目前蛋白质分子形态结构分形研究的基本情况以及未来可能的发展方向。  相似文献   

14.
1 Attack density and breeding success of bark beetles (Coleoptera: Scolytidae) and the abundance of their predators were studied at forest-clearcut edges in southern Finland on Norway spruce, Picea abies, bolts placed at different distances from a forest-clearcut edge. 2 Attack densities of two species, Hylurgops palliatus and H. glabratus, increased markedly towards the forest interior. The breeding success of H. palliatus was increased with increasing distance from the stand edge. None of the recorded 10 bark beetle species was distinctly abundant near the edge, but Pityogenes chalcographus appeared to prefer this zone. 3 There were no significant differences in numbers of bark beetle predators between the forest interior and the edge. Forest-clearcut edge had a significant effect on the desiccation of sample bolts. 4 Thus, forest edge is likely to affect the colonization behaviour and breeding success of bark beetles via host material properties.  相似文献   

15.
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Jing Wei  Gang Wu 《生态学报》2006,(7):2087-2092
Pinus tabulaeformis carr. and Hippophae rhamnoides are widely planted in the low mountainous upland and loess plateau and are the main species for afforestation in the semiarid region. To expound their roles in controlling severe soil and water losses and the mechanism of their roles, a study on the hydro-ecological effects of the woods was carried out during 2002–2004, using the runoff plot method set up in different woods and conducting a physical and chemical analyses of the soil. The experimental woods are located in the low mountainous upland of Western Liaoning Province, China where the annual average air temperature is 5.4–8.7°C, the annual precipitation is 450–580 mm, of which June averages 238.9 mm, and the annual average humidity is 38%–82%. The coverage rate of vegetation is 28%. The age of Pinus tabulaeformis carr. is 28 a, its distribution density is 2825 ind.·hm2, and its coverage rate is 0.75, while those of Hippophae rhamnoides are 11a, 8950 ind.·hm2 and 0.90, respectively. The results showed that the intercepting rates of canopy in Pinus tabulaeformis carr. and Hippophae rhamnoides were 23.08% and 32.28%. The litter intercepting rate averaged 14.17% in the Pinus tabulaeformis carr. woods and 20.8% in the Hippophae rhamnoides woods, respectively. The runoff depths in Pinus tabulaeformis carr. and Hippophae rhamnoides were 2.516 mm and 0.893 mm, while erosion amounts were 15.57 t·km?2 and 0.76 t·km?2, respectively. Under the comprehensive action in the artificial woods, the runoff depth and erosion amount from the woodland were 1/20 and 1/50 of those from the wasteland, respectively, which indicated the immense hydro-ecological functions of Pinus tabulaeformis carr. and Hippophae rhamnoides woods Litter and dead roots would decompose into organic matter and nutrient substances with the help of microbes, and would thus distinctly improve the physical and chemical properties of the soil. In comparison with the wasteland, the bulk density of soil decreased in the woodland, while the content of organic matter, total N, total K, and available K significantly increased. The physical properties of soil in the woodland, such as total porosity, noncapillary porosity, saturated moisture content, noncapillary water-holding capacity, were distinctly higher in surface soil (0–20 cm) than those in the soil at the depth of 20–40 cm. There was no significant difference of pH, total P, and available P among different land types or at different soil depths. The noncapillary water-holding capacities in Pinus tabulaeformis carr. and Hippophae rhamnoides were 182.1% and 275.9% times those of wasteland, respectively.  相似文献   

16.
    
Wei J  Wu G 《农业工程》2006,26(7):2087-2092
Pinus tabulaeformis carr. and Hippophae rhamnoides are widely planted in the low mountainous upland and loess plateau and are the main species for afforestation in the semiarid region. To expound their roles in controlling severe soil and water losses and the mechanism of their roles, a study on the hydro-ecological effects of the woods was carried out during 2002–2004, using the runoff plot method set up in different woods and conducting a physical and chemical analyses of the soil. The experimental woods are located in the low mountainous upland of Western Liaoning Province, China where the annual average air temperature is 5.4–8.7C, the annual precipitation is 450–580 mm, of which June averages 238.9 mm, and the annual average humidity is 38%–82%. The coverage rate of vegetation is 28%. The age of Pinus tabulaeformis carr. is 28 a, its distribution density is 2825 ind.·hm2, and its coverage rate is 0.75, while those of Hippophae rhamnoides are 11a, 8950 ind.·hm2 and 0.90, respectively. The results showed that the intercepting rates of canopy in Pinus tabulaeformis carr. and Hippophae rhamnoides were 23.08% and 32.28%. The litter intercepting rate averaged 14.17% in the Pinus tabulaeformis carr. woods and 20.8% in the Hippophae rhamnoides woods, respectively. The runoff depths in Pinus tabulaeformis carr. and Hippophae rhamnoides were 2.516 mm and 0.893 mm, while erosion amounts were 15.57 t·km-2 and 0.76 t·km-2, respectively. Under the comprehensive action in the artificial woods, the runoff depth and erosion amount from the woodland were 1/20 and 1/50 of those from the wasteland, respectively, which indicated the immense hydro-ecological functions of Pinus tabulaeformis carr. and Hippophae rhamnoides woods Litter and dead roots would decompose into organic matter and nutrient substances with the help of microbes, and would thus distinctly improve the physical and chemical properties of the soil. In comparison with the wasteland, the bulk density of soil decreased in the woodland, while the content of organic matter, total N, total K, and available K significantly increased. The physical properties of soil in the woodland, such as total porosity, noncapillary porosity, saturated moisture content, noncapillary water-holding capacity, were distinctly higher in surface soil (0–20 cm) than those in the soil at the depth of 20–40 cm. There was no significant difference of pH, total P, and available P among different land types or at different soil depths. The noncapillary water-holding capacities in Pinus tabulaeformis carr. and Hippophae rhamnoides were 182.1% and 275.9% times those of wasteland, respectively.  相似文献   

17.
High-resolution nuclear magnetic resonance of carbon 13 was employed to characterize archaeological wood samples from Portuguese medieval dugout canoes. Structural and chemical modifications were assessed by comparing the structural features of archaeological wood samples with modern wood. The main results concern the strong decrease of sugar moiety with a complete disappearance of hemicelluloses. During ageing in water environment, the β-O-4 inter-unit linkages of lignins have not been degraded. The features of the 13C NMR spectra clearly reveal that the products of degradation of the carbohydrates occurring during depletion of sugars were not recombined inside the lignocellulosic matrix. Finally, this article gives a clear illustration that although the water contents of archaeological wood can certainly be used as a good criterion concerning their state of degradation, solid-state 13C NMR lead to unambiguously data as far the structural properties of archaeological waterlogged woods are concerned.  相似文献   

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本文用方差分析区别具台木类木材的三个种:太原台木(Dadoxylon taiyuanensis),生根无髓根(Amyelon radicans)和徐氏无髓根(A.xui),并同国外的种比较,结果表明,用这种方法能定量地研究植物性状之间的区别,并得到较好的效果。  相似文献   

20.
    
Five angiospermous fossil woods of Late Tertiary have been excavated from Xinzhow County, Hubei Province. From the observation of the wood anatomical features they are pre- liminarily identified as Bischofia javanica B1., a species of Leguminosae, and two species of Lauraceae.  相似文献   

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