辽宁抚顺松材线虫入侵松林内天牛种类调查

【目的】松材线虫Bursaphelenchus xylophilus (Steiner&Buhrer) Nickle的媒介昆虫云杉花墨天牛Monochamus saltuarius Gebler在辽宁省被发现意味着我国北方松林的生态安全正在遭受严重的威胁。明确松材线虫入侵松林内的天牛种类、数目,可以为早期监测松材线虫媒介昆虫和潜在媒介昆虫的种群动态以及预测松材线虫病的发生提供参考。【方法】为了明确天牛广谱型引诱剂、APFI持久增强型松墨天牛高效诱剂、F8型松墨天牛引诱剂及其复配诱芯的诱捕效果,于2019-2020年的5-10月在辽宁省抚顺市的油松林、红松林、落叶松林开展诱捕天牛试验。【结果】将天牛广谱型引诱剂和F8型松墨天牛引诱剂放在同一诱捕器中具有较好引诱效果,每诱捕器捕获的天牛物种数量（油松林18种,红松林14种,共计19种）和天牛样本数量（油松林（18.31±8.86）头/周,红松林（23.44±10.92）头/周）最多。在试验林地共计诱捕到34种共计13307头天牛,其中云杉花墨天牛数量最多,占总诱捕量的67%,褐梗天牛Arhopalus rusticus、锯天牛Prionus insularis、小灰长角天牛Acanthocinus griseus、松皮花天牛Rhagium japonicum分别占总诱捕量的13.2%、6.6%、4.1%和2.7%。【结论】捕获到危害针叶树的天牛8种,包括云杉花墨天牛（优势种）、小灰长角天牛、灰长角天牛Acanthocinus aedilis、褐梗天牛、脊鞘幽天牛Asemum striatum和锯天牛。根据天牛的取食产卵习性推测,小灰长角天牛、灰长角天牛在补充营养的时候可能会传播松材线虫到健康松树上,而褐梗天牛、脊鞘幽天牛和锯天牛羽化成虫后不需补充营养且产卵在衰弱木的树皮缝隙或者表土处,它们有效传播松材线虫的几率较小。     

松材线虫及其传媒松墨天牛的监测和防治现状

松材线虫起源于北美大陆。1 982年侵入中国。松材线虫能引起一种林业上最具危险性、毁灭性的病害“松材线虫病”。松材线虫病的病因复杂,传播途径多样,不同国家地区对其采取的监测和防治策略也有所差异。目前,该病局限分布于北美和东北亚,但在世界范围内其扩散趋势日益明显。该文简要从监测预警,物理、化学、生物等防治方法、以及监测防治中存在问题和发展趋势等方面概述了国内外松材线虫Bursaphelenchusxylophilus及其关键传媒松墨天牛MonochamusalternatusHope的研究现状,对制定适宜我国的松材线虫病监测和防治策略有借鉴和参考价值。     

温度对松褐天牛传递松材线虫数量的影响

松材线虫病是一种重要的检疫性病害,松褐天牛是传播松材线虫的主要媒介昆虫.本实验研究了温度对松褐天牛传递松材线虫数量的影响.设置22℃、28℃和34℃ 3个温度梯度,结果表明松褐天牛成虫的寿命随温度升高而缩短,其中雌虫寿命短于雄虫,且羽化进度不太一致,多数松褐天牛携带的松材线虫量在1000～9999条之间.通过对松褐天牛取食传入松枝的松材线虫量的追踪记录发现,随着温度升高,传播线虫的高峰时段随之提前.34℃高温下松褐天牛的传递率最低,表明高温对松材线虫病的发生具有抑制作用.     

松墨天牛成虫体内的松材线虫分布和速检研究

为了探索快速测定松墨天牛成虫(下称成虫)的带疫性,用解剖方法和自制便携式显微镜,对成虫携带的松材线虫部位和速检(下称线虫)作了研究,得到下列结果：87．9％的线虫分布在成虫的节间、腹腔和生殖器内;雄成虫阳茎是松材线虫集中分布区,两头平均携带线虫498．5条;交尾时雄成虫把阳茎上的线虫传到雌成虫外生殖器,在雌成虫产卵时再把线虫带入松树形成层组织;在野外检测成虫带疫性平均需时1．57min。     

皮下接种松墨天牛卵及幼虫致死松树的研究

为了探明松墨天牛MonochamusalternatusHope直接致死松树的作用 ,作者采用在健康松树皮下接入松墨天牛卵或初孵幼虫方法做了试验和观察。结果表明 ,接入卵或初孵幼虫的松树平均枯死率为41 . 7%。松树枯死取决于松墨天牛幼虫取食时对松树韧皮部的破坏程度。每株接入 5个单位 (1单位指1粒卵或条初孵幼虫 ) ,松树枯死率达 85. 7% ;接入 1个单位 ,枯死率为 1 0 %。初步结论是 ,松墨天牛是引起松树枯死的主要原因之一 ;大力防治松墨天牛是保护我国松林的关键。     

松材线虫的天然毒素研究进展

概述了松材线虫病的现行防治措施及存在问题,介绍了植物源和真菌源天然毒素毒杀松材线虫的研究现状及研究中遇到的问题,指出天然毒素在未来松材线虫病生物防治中的研究方向。     

携带松材线虫对松墨天牛成虫肠道和气管细菌的影响

【目的】探究被松墨天牛Monochamus alternatus携带的松材线虫Bursaphelenchus xylophilus对松墨天牛肠道和气管细菌的影响。【方法】野外采集携带松材线虫的松墨天牛成虫后,取出完整肠道和气管进行细菌总DNA抽提后进行16S rDNA基因测序并拼接,并利用生物信息学方法分析松墨天牛成虫肠道和气管细菌组成、结构、丰度和多样性。【结果】携带松材线虫的松墨天牛成虫肠道和气管细菌菌群共检测到15门26纲66目110科201属296种,可操作分类单元(operational taxonomic unit, OTU)数目为444。携带松材线虫的松墨天牛成虫比未携带松材线虫的松墨天牛成虫肠道优势细菌菌群变化不显著,均为变形菌门(Proteobacteria)肠杆菌目(Enterobacterales);携带松材线虫的松墨天牛成虫气管优势细菌菌群为变形菌门肠杆菌目,未携带松材线虫的松墨天牛成虫气管优势细菌菌群为厚壁菌门(Firmicutes)乳杆菌目(Lactobacillales)。携带松材线虫的松墨天牛成虫较未携带松材线虫的松墨天牛成虫气管细菌多样性和丰度升高,细...     

携带与非携带松材线虫的松墨天牛miRNA表达谱比较分析

【目的】松墨天牛是松树的重要蛀干害虫,也是林业重大外来入侵种松材线虫的媒介昆虫。虽然松墨天牛和松材线虫互作的化学生态和分子进化机制受到人们的广泛关注,但miRNA等表观遗传因子在天牛—线虫互作中的作用未见报道。【方法】使用illumina HiSeq 2000平台进行miRNA高通量测序,得到4个携带线虫的天牛miRNA库和4个未携带线虫的天牛miRNA库。此外,对鉴定出的miRNA进行了差异表达分析,并对这些miRNA的靶基因进行了GO注释和KEGG通路富集分析。【结果】在携带线虫的天牛表皮、脂肪体、中肠和气管样本中分别鉴定出780、802、617和762个miRNA;在未携带松材线虫的天牛的不同组织样本中分别鉴定出784、723、713和837个miRNA。在携带松材线虫的松墨天牛中,某些已知miRNA表达量会显著升高,如miR-14、miR279和miR-312等。差异表达miRNA的功能大多指向代谢、免疫等方面。【结论】miRNA在松墨天牛和松材线虫互作中起着重要的调控作用。     

树木生长势与松墨天牛种群密度及松材线虫发病程度关系

对不同生长势林区内的松墨天牛种群密度和松材线虫发病程度的研究表明,树木生长势（x）分别与松墨天牛种群密度（y）、松材线虫发病程度（z）呈负相关,其线性回归方程分别为：y=1793.771-16404.47x;z=31.80989-241.9274x,相关系数分别为r=-0.8319和r=-0.8770。而松墨天牛种群密度（y）与松材线虫发病程度（z）呈正相关,其线性回归方程为：y＝－407.0611＋70.51478z;相关系数为r=0.9864。     

Transmission of the pine wood nematode Bursaphelenchus xylophilus through feeding activity of Monochamus galloprovincialis (Col., Cerambycidae)

Abstract:  Transmission of the pinewood nematode (PWN) Bursaphelenchus xylophilus (Steiner & Bührer) Nickle to Pinus pinaster Aiton branches through feeding wounds of its vector in Portugal, Monochamus galloprovincialis Olivier, was studied under laboratory conditions. All the B. xylophilus -infected beetles transmitted nematodes to branches they fed. The transmission was more frequent during the first 6 weeks after emergence, with transmission peaks during the second and the sixth week. The adult M. galloprovincialis transmitted nematodes for a mean of 5 weeks, independently of the beetle's sex or longevity. No relation was found between beetle feeding intensity and effective transmission of B. xylophilus to the branches. The nematode transmission ceased after the ninth week, even in insects which still had B. xylophilus on their bodies. The longevity of the nematode-free insects (control group) was slightly higher than the B. xylophilus -infected beetles, although with no significant difference. The results emphasize the necessity to control the immature stages of M. galloprovincialis prior to emergence and develop efficient strategies to capture and eliminate the recently emerged beetles, as majority of the nematode infection of healthy pine trees occurs during a short period of few weeks after beetle emergence.     

Spatial pattern of pine wilt disease caused byBursaphelenchus xylophilus (Nematoda: Aphelenchoididae) within aPinus thunbergii stand

To understand the mechanism of spread of pine wilt disease caused by the pinewood nematode, Bursaphelenchus xylophilus, which is vectored by a cerambycid, Monochamus alternatus, the spatial distribution of trees weakened by the nematode was examined within a Pinus thunbergii stand from June to October for 4 years. The weakened trees were distributed in a clumped pattern in 1980 and 1981, at an early stage of infestation. In many cases, they showed a double-clumped pattern. The degree of aggregation was higher in June or July than after August. They were uniformly distributed in June or July 1982 and in June 1983 whereas they showed a double-clumped pattern after August. The trees were frequently weakened in June or July when they were near the trees weakened during the previous year. At quadrat sizes of more than 25 m², spatial overlapping was pronounced between trees weakened during June–July of the current year and those weakened in the previous year. The seasonal changes in spatial distribution of weakened trees were explained by the interaction among M. alternatus, B. xylophilus and Pinus trees.     

季也蒙假丝酵母对松材线虫病的抑制作用

松材线虫病是重要的森林病害,该病与松材线虫携带的病原菌和松树的内生病原菌密切相关。在室内条件下,初步研究了从人工培养的松材线虫上分离到的菌株C对松材线虫病的抑制作用。在健康的水培马尾松枝上分别接种松材线虫接种液、菌株C接种液、松材线虫与菌株C的混合接种液。处理后松枝的相对重量与相对蒸腾强度均为:接种菌株C的松枝>混合接种的松枝>接种线虫的松枝。处理后15d时,接种线虫的松枝与混合接种的松枝的相对重量有显著性差异(p<0.05)。接种线虫松枝的存活期显著短于其它处理松枝的存活期(p<0.05)。接种菌株C的针叶褐变株数少于接种线虫的松枝,两者有显著性差异(p<0.05)。从接种线虫和混合接种的所有松枝中都分离到松材线虫,且分离出的线虫量没有显著性差异。将8个月生的断根马尾松苗插入菌株C的查彼培养液的滤液中培养,6d后松苗的平均感病指数和感病株率均显著少于对照(p<0.05)。这表明,菌株C对松材线虫病有抑制作用,菌株C培养液中产生的某些代谢物质有利于松苗的抗病和存活。菌株C可能抑制了松树上的内生病原菌和松材线虫携带的病原微生物,或提高了松树的生长力和抗逆能力。经电子显微镜观察并参照AP I 20 C AUX鉴定系统鉴定,菌株C为季也蒙假丝酵母C and id a gu ilierm ond ii。     

松墨天牛的全球潜在分布区分析

松墨天牛MonochamusalternatusHope分布在亚洲东部,是松材线虫Bursaphelenchusxylophilus(SteinerandBuhrer)在亚洲最有效的昆虫媒介,同时也是重要的蛀干害虫。利用CLIMEX模型分析松墨天牛分布区的气候限制因子,并在全球范围预测它的潜在分布区。模型分析结果表明,温度和降水是松墨天牛分布区的主要气候限制因子。温度在30°N以北地区和30°S以南地区主要表现为冷胁迫,在非洲中部、南亚和澳大利亚北部表现为热胁迫。有效积温不足可能是限制松墨天牛向北扩散的主要原因。降水在中国西北地区、非洲中北部、澳大利亚中部和西部与美国西部主要表现为干胁迫。降水量对分布区范围影响不大。预测结果表明,松墨天牛的全球潜在分布区远远大于实际分布范围。松墨天牛在东半球的潜在分布区包括亚洲东部和南部地区、地中海沿岸、非洲的中部和南部以及澳大利亚的东部和南部,在亚洲热带的潜在分布区1年3代,地中海地区1年1代,非洲1年2～3代,在澳大利亚主要1年1代。松墨天牛在西半球的潜在分布区主要集中在美国南部和东部沿海地区,中美洲以及南美洲的广大地区,美国主要1年1代,中美洲1年2～3代,南美洲主要1年2代。     

Viability and pathogenicity of Esteya vermicola in pine trees

Esteya vermicola, as the first reported endoparasitic fungus of pinewood nematode (PWN), exhibited high infectivity in vitro and has been patented based on its potential as a bio-control agent against PWN. The isolation substrates and taxonomic status suggested E. vermicola is associated with beetles, saprotrophic and kills nematodes in trees. However, the direct experimental evidence for this was still lacking. In the present studies, beta-tubulin gene was applied to confirm the taxonomic identification of E. vermicola. Furthermore, our results showed that E. vermicola survived resin and other chemicals secreted by pine trees, and reproduced with new lunate conidia to parasitize other migratory PWNs. In order to confirm the pathogenicity of E. vermicola, pine seedlings and large pine trees were inoculated with 300 µL and 40 mL conidia suspensions (10⁹ mL^?1). The results showed that all treated pine trees were healthy with no differences compared to the controls. Furthermore, necrosis or discoloration caused by this fungus was not observed on wood slices. Basal knowledge was provided for the application of E. vermicola to control PWN in vivo.     

Regioselectivity in Sulfation of Galactosides by Sulfuric Acid and Dicyclobexylcarbodi-imide

Methyl α- and β-D-galactopyranosides and 4-O-β-D-galactopyranosyl-3,6-anhydro-L-galactose dimethylacetal were sulfated with sulfuric acid and dicyclohexylcarbodi-imide as a condensation reagent. The sulfated sugars were isolated by ion-exchange chromatography, characterized, and assigned by methylation analyses. On the basis of the yield of each sulfated product that was isolated, sulfation on O-6 appeared to be predominant.     

基于MaxEnt模型预测四川省松材线虫的潜在适生区

松材线虫Bursaphelenchus xylophilus是我国重要的林业检疫性有害生物之一,由其引发的松材线虫病已造成巨大的经济损失,严重阻碍了林业的健康发展。研究并明确松材线虫在四川省的潜在适生区,对四川省有关部门制定该病害的早期监测、预警及防控具有一定的参考意义。本文基于2009—2018年四川省林业有害生物普查数据中松材线虫病和松墨天牛Monochamus alternatus的实际地理分布数据(松材线虫病:n=208,松墨天牛:n=803)及19个环境变量数据,利用MaxEnt模型和Arc GIS对松材线虫在四川省的潜在分布区进行预测,并用ROC曲线分析法检测模型模拟精度、用刀切法检测变量的重要性及其适宜值。结果表明:松材线虫在四川省的潜在最佳适生区主要分布在宜宾市、广安市、达州市、自贡市、西昌市,以及乐山市和眉山市的交界区,面积为36 541 km^2;影响松材线虫分布的主要环境变量为最干季均温(适值范围1. 5～8. 0℃,最适值6. 4℃)、季节性降水变异系数(适值范围22. 5%～34. 0%,最适值34. 0%)、最冷月最低温(适值范围0. 4～2. 5℃,最适值1. 9℃)、海拔(适值范围250～5 500 m,最适值450 m)、年温差(适值范围5. 9～9. 1℃,最适值5. 9℃)和年降水量(适值范围64～135 mm,最适值68 mm)。