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1.
《Southern Forests》2013,75(3-4):173-179
Pinus patula is the softwood species most extensively planted in South Africa. However, large portions of these plantings are under threat from Sirex noctilio infestation and occasional forest fires. In this exploratory investigation, the effects of tree age, Sirex noctilio infestation and fire damage to wood from Pinus patula trees on their pulp and paper properties were evaluated. Pulp was produced using the thermomechanical pulping (TMP) process. The energy consumption required to pulp the different pulpwood materials was determined. Pulps were beaten for five different time periods to investigate the development of the fibre properties in response to increasing energy input. Paper properties such as burst, tear strength and breaking length were determined on handsheets manufactured from unbeaten and beaten pulps. Box and line plots and canonical variate analysis biplots were used to statistically analyse the data. It was found that the burst strength of paper produced from healthy trees was significantly higher than that from sirex-infested or fire damaged (burnt) trees. Similarly, the tear strength of paper from healthy and burnt trees was significantly better than from sirex-infested or young trees. No significant differences in breaking length were evident between the pulpwood materials and an increase in beating time did not lead to any improvements. From this study it can be concluded that wood from dead or dying, sirex-infested and young trees produced paper with consistently lower strength properties compared to wood obtained from healthy 12-year-old trees.  相似文献   
2.
以新伐油松(衰弱树)作为饵木,在北京香山公园从海拔、坡度等不同的立地条件下选取6处林地作为饵木设置地,对饵木诱集新渡户树蜂效果进行了研究.结果表明:饵木诱集新渡户蜂效果较为明显,饵木上平均诱集3.9只·m-2.海拔越高处诱集到的树蜂数量越多,饵木的表面积与诱集的数量无显著相关,同时树蜂多集中在中午前后交尾产卵.诱集到的...  相似文献   
3.
松树蜂(Sirex noctilio Fabricius)是一种重要的国际检疫性蛀干害虫。目前在我国松树蜂潜在寄主范围内,不同树种对松树蜂毒素抗性之间的差异尚不明确。本文以室内栽培的2~3 a生油松、樟子松、红松、湿地松、马尾松及雪松这6种树种为供试寄主,培育3个月后分别接种毒素、毒素真菌混合液并测定每株枝条针叶的RGB值以及叶绿素含量。结果表明,形态上油松和樟子松幼苗接种毒素、毒素真菌混合液后一段时间内,均出现了比较明显的针叶枯黄、脱落的现象,且混合组长势萎蔫,脱落严重,对照组无明显变化。马尾松幼苗只有接种混合液后变化明显,雪松、红松、湿地松接种后长势强劲,长出新芽。从数值化的角度,油松和樟子松幼苗接种毒素、毒素和真菌混合液后,针叶的RGB值减小及叶绿素含量值显著降低。马尾松幼苗只有接种混合液后,RGB值和叶绿素含量才减小。雪松、红松、湿地松接种毒素以及毒素真菌混合液后,RGB值及叶绿素含量均没有明显变化。以上可以看出樟子松和油松对于松树蜂毒素、毒素真菌混合液的抗性较弱,马尾松对松树蜂毒素具有一定的抗性,对毒素真菌混合液的抗性较弱,红松、湿地松、雪松对两者都具有一定的抗性。该结果可为明确松树蜂在我国潜在的寄主范围及寄主选择性提供科学依据。  相似文献   
4.
根据国际通用的有害生物分析方法,对松树蜂在吉林省的风险性进行综合分析,结果表明:松树蜂在吉林省的风险评估值为2.56,属于高度危险性林业有害生物,扩散和传播的可能性极大。应采取严格的检疫和预防措施,防止松树蜂在我省发生和蔓延。  相似文献   
5.
Sirex noctilio is one of the most important invasive pests that affect Pinus radiata plantations in Chile. Its management is based on a biological control complex, the most important component of which is the nematode, Deladenus siricidicola. However, in some areas, S. noctilio populations attain epidemic levels and no effective control methods exist to reduce large populations in a short period. In this study, we evaluated a novel method called mega-trap-plots (MTPs), which consist of an area of 1 ha with trap trees, which were debilitated in four different months (from November to February) with the purpose of reducing the Sirex wasp population through harvesting of trees attacked. The main objective was to reduce the potential population of S. noctilio, by evaluating four periods or months of MTP installation to maximise the colonisation of trap trees by wood wasps. The results showed that the MTPs that were installed from November to January had the highest wood wasp infestation, which was coincident with the flight period of the insect. The trap trees were clearly attractive to S. noctilio females up to 90 d following their establishment. The MTPs that were established in November concentrated a potential population of 57 901 females of S. noctilio, which represents a population 5.4 times greater than that in the control, with 10 701 females. The population of S. noctilio attracted between November and January shows that the use of MTPs is an effective system for the management of wood wasps on plantations with a high level of infestation and thereby can reduce their spread and the attack of new trees within the same forest compartments.  相似文献   
6.
为探究入侵我国的重大林业检疫性害虫松树蜂Sirex noctilio的气味结合蛋白(odorant binding protein,OBP)与其相关信息化学物质的结合模式和结合能力,采用Swiss-model在线服务器对松树蜂触角中高表达的4种OBP序列进行同源模建,采用Procheck、Verify_3D和ERRAT程序对模建质量进行评价;并应用Autodock软件对OBP模型和相关信息化学物质进行分子对接分析。结果显示,在松树蜂触角中高表达的4种蛋白为SnocOBP4、SnocOBP6、SnocOBP9和SnocOBP12,其同源模建所得模型质量较好:均满足拉氏构象图中氨基酸位于最佳合理区的数量大于90%的条件;三维结构与一级结构的兼容性评分大于0.2;所得ERRAT值分别为85.71%、95.10%、98.15%和91.82%。分子对接显示,与松树挥发物α-蒎烯和β-蒎烯结合最好的蛋白是SnocOBP12,结合能分别为-5.36 kJ/mol和-5.48 kJ/mol;与雌性信息素成分顺-9-二十九烯结合最好的蛋白是SnocOBP4,结合能为-5.42 kJ/mol;与雄性信息素成分顺-3-癸烯醇和顺-4-癸烯醇结合最好的蛋白是SnocOBP9,结合能分别为-4.37 kJ/mol和-4.45 k J/mol;而3-蒈烯、顺-7-二十七烯和反-2,4-癸二烯醛等气味分子与SnocOBP6的结合能较低,结合能最低的是顺-7-二十七烯,为-6.08 k J/mol。雄蜂主要信息素成分顺-3-癸烯醇与其同分异构体反-3-癸烯醇相比,与SnocOBP9的结合能较低;但是反-3-癸烯醇能以较强的氢键竞争SnocOBP9结合位点。研究表明这4种松树蜂OBP与相应植物挥发物或雌雄信息素具有较好的亲和力,参与了松树蜂对不同信息化学物质的识别过程。  相似文献   
7.
以在黑龙江、内蒙古松树蜂(Sirex noctilio)发生区采集的松树蜂为研究对象,解剖松树蜂雌成虫腹部找到毒素腺和毒素囊的位置并在显微镜下观察其结构特点;用赛默飞气相色谱质谱联用仪,设定50℃开始升温,在5℃·min-1升到200℃条件下分析毒素成分。结果表明:毒素腺和毒素囊位于松树蜂的产卵器基部,毒素囊为绿豆粒大小半透明晶状组织,其结构特点有利于松树蜂储存尽可能多的毒素。毒素含有生物碱、糖及糖苷、脂肪酸和蛋白质等物质,其中脂肪酸类物质占主要比例,包括棕榈酸、十六碳烯酸、硬脂酸、十八烷酸等酸,毒素成分中的蛋白质可能是对寄主树木造成伤害的活性物质。  相似文献   
8.
文章介绍了云杉蓝树蜂在国外的生物学特性、危害及防治情况,提出在对进境木材及货物木质包装的检疫过程中,应加强对云杉蓝树蜂的检疫工作,以免其传入我国。  相似文献   
9.
The woodwasp, Sirex noctilio , and its symbiotic fungus, Amylostereum areolatum , cause extensive damage to pine plantations in the Southern Hemisphere. S. noctilio was first reported from South Africa in 1994. In this study, the population diversity of A. areolatum isolates from South Africa, South America, Australasia and Europe was determined by vegetative incompatibility testing. All 108 South African and 26 South American isolates belonged to the same vegetative compatibility group (VCG). This VCG showed a weak incompatibility reaction with the single Tasmanian and single New Zealand isolates tested. This VCG differed from VCGs from Europe. It also differed from isolates associated with the biocontrol nematode, Deladenus siricidicola , which is produced in Australia. It is concluded that the South African and South American populations of A. areolatum share a common origin .  相似文献   
10.
为探究我国重大入侵害虫松树蜂Sirex noctilio的嗅觉分子机制,通过RT-PCR技术克隆松树蜂嗅觉共受体SnocOrco基因的cDNA全长序列,并进行生物信息学分析,且采用qPCR技术明确SnocOrco在组织中的特异性表达谱和时空表达特性。结果表明,SnocOrco基因(GenBank登录号:MK748989)开放阅读框全长1 446 bp,编码481个氨基酸,氨基酸序列具有7个跨膜螺旋结构和1个高度保守结构功能域Pfam:7tm_6。SnocOrco属于稳定的疏水性膜蛋白,同源性比对和系统发育分析结果显示,氨基酸序列与膜翅目、鳞翅目、鞘翅目和双翅目其它昆虫的Orco都具有很高的同源性,其中与麦茎蜂Cephus cinctus的CcinOrco同源性最高,达到87.14%,在系统发育树中聚为一支。qPCR结果显示,SnocOrco主要在雌、雄成虫触角中高表达,约为外生殖器中表达量的6 000倍和4 000倍,且在雌成虫中的表达量高于雄成虫中的表达量;在2~7日龄成虫触角中SnocOrco的相对表达量在2日龄时达到最高,之后随着日龄的增加呈下降趋势;昼夜节律显示,SnocOrco相对表达量从9:00—15:00呈先上升后下降的趋势,在11:00时达到最高。表明SnocOrco基因在松树蜂两性交流中起着重要作用。  相似文献   
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