松材线虫病的潜伏侵染及松墨天牛传播途径

在南京用松材线虫接种7种松树，于第2a在无任何症状的松树的接种点上方10cm处取样，分离线虫，结果表明松材线虫病的潜伏侵染现象比较普遍，在不同的松树品种上潜伏侵染现象有所差异，感病黑松和赤松很快死亡，只有在接种量小的情况下才有潜伏侵染现象发生，抗病性强的火炬松和湿地松感病后潜伏侵染现象比较普遍，并且样品中的线虫量也较高，而抗病性中等的马尾松和刚松感病后潜伏侵染现象的普遍性及样品中的线虫量均处于中等，短针松接种松材线虫后既不枯死，也无潜伏侵染现象，松墨天牛传播松材线虫的试验结果表明，未携带松材线虫的松墨天牛成虫在松材线虫病松枝上取食后，再到健康松枝上取食，有传播松材线虫的可能，这些结果表明在松材线虫病新病区清理病死木时，应采取早期诊断技术，把未表现症状的松树一起清除，以达到防治目的。     

黄山市预防松材线虫病对策

松材线虫病是松树的一种毁灭性病害,它发病迅速,侵染性强,防治极其困难,松树一旦感病就意味着死亡,被称为松树的"癌症",已被很多国家列为头号森林植物检疫对象。一、黄山市松材线虫病预防形势松材线虫病传播方式有两种,一种是自然传播,另一种是人为传播。自然传播主要是媒介昆虫松褐天牛迁飞取食和产卵将松材线虫从疫区带入非疫区;人为传播主要是人为调运疫木及     

松墨天牛种群动态监测和诱捕器野外应用技术探讨

指出了松墨天牛是松材线虫的主要传播媒介和携带者,随着松墨天牛的取食和产卵,松材线虫会进入到松树中,故当前世界各国不仅充分重视松材线虫的防治,同时还加强对松墨天牛防治的研究,将其作为松材线虫病的一种主要防控措施。基于此,针对松墨天牛种群动态监测和诱捕器野外应用技术进行了探讨。     

松材线虫病及其媒介昆虫松墨天牛的生物防治

指出了松材线虫病也称松树萎蔫病,是一种国际性检疫病害。自20世纪80年代传入南京,该病害传播速度快,我国现疫区包括重庆在内多达17个省市。松材线虫病原为松材线虫,其病原的主要传播媒介为松墨天牛M,针对松墨天牛的生物防治进行了调查研究,整合国内外对松墨天牛生物防治资料,对其提出了生物防治方法,为我国松材线虫病的生物防治提供理论依据。     

拟松材线虫病的危害与防治

近年来 ,在贵阳市第一环城林带和其它松林区发现了拟松材线虫病和松墨天牛为害。 2 0 0 1、2 0 0 2年连续两年组织有关人员开展调查表明 ,拟松材线虫病在贵阳市危害十分严重 ,已造成大量松树枯死 ,对森林资源和环境构成严重威胁。1　危害特征拟松材线虫病 2 0世纪 80年代陆续在一些省区松林中发生 ,引起松树萎蔫 ,并造成一定的危害。此病多发生于一些成过熟林分中 ,由于松树生长衰弱 ,受次期害虫天牛、小蠹、吉丁虫等蛀干害虫危害 ,并携带拟松材线虫侵染松树后 ,加速了松树枯死。据观察 ,松树感染拟松材线虫后 ,其外部症状表现与松材线虫病…     

温度对松墨天牛传播松材线虫的影响

【目的】研究温度对松墨天牛传播松材线虫的影响,为松材线虫病的预防和防治提供理论与技术支持。【方法】设置3个恒定温度（15、20和25℃）环境,将150只松墨天牛分为3个组（各组50只）,分别在3个恒定温度下饲养,测定不同温度条件下松墨天牛的寿命及松材线虫的存活情况,探讨温度对松墨天牛传播松材线虫的影响。【结果】松墨天牛平均寿命随着温度的降低而降低。3种温度处理对松墨天牛平均寿命的影响存在显著差异,但对初始松材线虫数量无影响。松墨天牛寿命与温度有关,而与体重无关。松墨天牛携带的松材线虫数量在最初的5 d内基本不变,然后随着松墨天牛年龄的增加而减少。当松墨天牛初始携带100～999条松材线虫时,平均传播效率随着环境温度的降低而降低;当线虫初始负荷为1～99时,温度处理对松材线虫平均传播效率的影响不显著。随着温度的降低,松材线虫离开松墨天牛所需的时间增加,松材线虫离开松墨天牛所需的时间在25℃时最短,在15℃时最长。3种温度处理下松材线虫传播效率都呈单峰传递曲线,松材线虫携带量峰值随着温度的降低而降低。【结论】环境温度降低,松墨天牛寿命缩短,线虫传播效率降低,线虫传播高峰期推迟,峰值降低,表...     

利用川硬皮肿腿蜂携带高毒力白僵菌微胶囊防治松墨天牛的研究

松墨天牛（Monochamus alternatus）是松材线虫（Bursaphelenchus xylophilus）传播的主要媒介昆虫之一,为了更有效地控制松材线虫病的传播,本文通过比较6株不同来源白僵菌对松墨天牛的毒力,筛选出致病性最好的菌株与3种高分子材料混合制备成微胶囊,比较不同微胶囊在川硬皮肿腿蜂（Scleroderma sichuanensis）体表的附着力以及室内对松墨天牛的侵染效果。结果表明：分离自松墨天牛感病虫体的菌株B2在生长性状和对松墨天牛的致病力上均优于其他菌株;海藻酸钠微胶囊对川硬皮肿腿蜂体表附着率达63%以及室内试验中对松墨天牛的侵染率达60%。本次研究证明了利用天敌昆虫携带病原真菌微胶囊防治蛀干害虫的可行性。     

松材线虫病的疫木除治及综合防治方法

<正>1松材线虫病基本情况松材线虫病又称松树萎蔫病,被称为松树的癌症,是松树的一种毁灭性流行病。松材线虫体长约1毫米,肉眼不易看到,通过松褐天牛等媒介昆虫侵入松树,破坏、堵塞松树疏导组织,具有传播途径多、发病部位隐蔽、发病速度块、潜伏时间长、治理难度大等特点。远距离传播主要依靠带有松材线虫病的松木木材及其制品传播,近距离传播主要依靠媒介昆虫松褐天牛等传播。松材线虫病发生后,最短40天左右就能导致整株松树失水死亡,如不采取有效措施防治,3～5年即可造成整片松林毁灭,带来的经济和生态损失巨大,其防治工作是世界性难题,对松林资源构成严重威胁。     

松褐天牛雌雄成虫的判别

松褐天牛Monochamus alternatus Hope是我国松林习见的重要蛀干害虫,也是松材线虫病的媒介昆虫。成虫羽化后,其气管携带大量线虫在成虫取食松树嫩皮时,线虫即经伤口进入树体。因此,成虫期不仅是天牛取食、扩散及生殖活动的重要时期,也是携带、传播松材线虫的关键虫态,是研究和防治松褐天牛及松材线虫病的重要环节。迅速而准确地判别松褐     

怎样做好松材线虫病的预防

松材线虫属于线形动物门线虫纲滑刃科,是重要的检疫性有害生物。松材线虫病是世界上最具有危险性的森林病害,在我国主要依靠松墨天牛传媒及人为活动作远距离传播,松树染病后40天既可枯死。我国自1982年首次发现以来,松材线虫病已经扩散到全国6个省,60多个县,直接威胁5亿亩松林和一批世界自然文化遗产、国家重点风景名胜区及重点生态区的安全。我省是松材线虫适生区,易感松材线虫病的树种马尾松、油松、华山松、白皮松分布广泛。因此,预     

Comparison of the gene expression profiles of resistant and non‐resistant Japanese black pine inoculated with pine wood nematode using a modified LongSAGE technique

The Japanese black pine (Pinus thunbergii) is highly susceptible to pine wilt disease caused by the pine wood nematode (PWN; Bursaphelenchus xylophilus). To cope with this disease, researchers and tree breeders selected PWN‐resistant individuals in a previous breeding program. In an attempt to understand the mechanisms of resistance in the Japanese black pine, we created four LongSAGE (serial analysis of gene expression) libraries. A total of 20 818 tags were studied, including 5194 tags from a PWN inoculated resistant pine, 5218 a non‐inoculated resistant pine, 5194 an inoculated non‐resistant pine, and 5212 a non‐inoculated non‐resistant pine. The analysis of the libraries indicated that 14 tag species were significantly up‐regulated (e.g., pathogenesis‐related proteins 2 and 4, osmotin, lipoxygenase, and chalcone synthase), and nine were down‐regulated (eukaryotic translation initiation factor SUI1, translationally controlled tumor protein, and xyloglucan endotransglycosylase) by the PWN inoculation in both the resistant and non‐resistant pines. On the other hand, 38 tag species were significantly expressed at a higher level only in the resistant pine (catalase, dienelactone hydrolase family protein) and 25 were expressed at a higher level in the non‐resistant pine (pathogenesis‐related proteins 1, 2, and 3, and leucoanthocyanidin dioxygenase). These differentially expressed genes are presumed to reflect some of the differences between the resistant and non‐resistant pines. Our results provide valuable information on the complex responses induced in the resistant and non‐resistant pine trees in response to PWN invasion.     

Migration of Bursaphelenchus xylophilus in cortical and xylem axial resin canals of resistant pines

Migration of the pine wood nematode (PWN), Bursaphelenchus xylophilus, in susceptible and resistant pines was investigated at the tissue level. PWN was inoculated onto the top cross‐cut surface of 20‐cm stem cuttings of susceptible Pinus thunbergii and resistant pines (P. strobus, P. rigida and P. thunbergii of a resistant family Namikata‐(t)‐73 (half‐sib)). PWNs were mainly distributed in cortical resin canals of susceptible P. thunbergii down to 15 cm from the inoculated surface by 6 h after inoculation (HAI) and all tissues (including cortical and xylem resin canals) down to the bottom at 192 HAI. In P. strobus, P. rigida and P. thunbergii family Namikata‐(t)‐73 (half‐sib), PWN was distributed in cortical resin canals down to 5 cm by 6 HAI and down to the base at 192 HAI. However, the distribution of PWN in xylem resin canals of the resistant pines was restricted near inoculated surfaces down to 5 cm, even at 192 HAI. These results demonstrated that migration of PWN in resistant pines was slowed in cortical resin canals and restricted in xylem axial resin canals, features which may be associated with the resistance.     

Correlation of seedling size and branch number with disease resistance of Pinus thunbergii seedlings to Bursaphelenchus xylophilus

Japanese black pine (Pinus thunbergii) seedlings resistant to pine wood nematode (PWN; Bursaphelenchus xylophilus) are routinely selected in Japanese field inoculation trials. Correlations between morphological factors (such as height, stem diameter at ground level and number of branches on seedlings) and disease resistance were examined to improve the production efficiency of 1‐year‐old black pine seedlings for inoculation. Family relatedness and environmental conditions strongly affected seedling resistance; accordingly, logistic regression analysis was used to separate effects of these two variables. Height and stem diameter at ground level significantly correlated with disease resistance in seedlings inoculated with PWN. Because (a) interactions between stem diameter at ground level and environmental condition were significant and (b) height did not interact with any other factor, it was concluded that height of 1‐year‐old Japanese black pine seedlings independently correlated with PWN resistance. Thus, field inoculation tests should use tall seedlings to achieve enhanced survival rates.     

抗松材线虫病马尾松种源化学成分与抗性机理研究（第Ⅲ报）——接种松材线虫引起抗性马尾松种源中性萜类含量变化关系的研究

通过气相色谱分析研究了高抗、中抗和敏感马尾松种源在接种松材线虫（PWN）后所引起的中性萜类（主要是倍半萜类）组分含量变化规律以及含量变化与种源抗性间相关性变化规律。结果表明，接种PWN使抗性马尾松种源中某些萜类组分如长叶烯等增多，而某些组分如反式石竹烯等减少；接种PWN使高抗种源中长叶烯与反式石竹烯含量比值先减小后增大，且超过接种前的水平，但是未改变种源的抗病特征；树木生长过程对种源抗性及本研究没有造成影响和干扰。     

不同松树感染松材线虫后NO和核酸酶变化与其抗病性的关系

以黑松、马尾松和火炬松为研究对象,对其接种松材线虫后4,12,24,48,72,96和120 h的NO和核酸酶的活性进行测定.3种松树接种松材线虫后,针叶内NO平均含量的积累为火炬松＜马尾松＜黑松,这种差异在12 ～48 h尤为明显;48h后较其割伤处理(CK1)的增加幅度为火炬松＞马尾松＞黑松.同时3种松树接种后的核酸酶变化趋势存在差异,单链核酸酶活性在4～48 h为火炬松＞马尾松＞黑松,而火炬松双链核酸酶活性在4～96h时却一直低于马尾松和黑松,这表明不同松树体内单链或双链核酸酶的活性变化与其抗病性有关.且3种松树在接种松材线虫后,表现出症状的时间顺序为黑松最早,马尾松次之,火炬松最晚.这表明NO和核酸酶的变化与松树感染松材线虫后的病程发展密切相关.     

Migration of pine wood nematodes in the tissues of <Emphasis Type="Italic">Pinus thunbergii</Emphasis>

The distribution of pine wood nematodes (Bursaphelenchus xylophilus, PWNs) in Japanese black pine (Pinus thunbergii) tissues was investigated by staining with fluorescein isothiocyanate-conjugated wheat germ agglutinin. After PWNs were inoculated to current-year stems of pine seedlings, their distribution at about 5 cm below the inoculation site was confined only to cortical resin canals 1 day after inoculation, and then spread to other tissues, including resin canals of short branches. When PWNs were inoculated onto cross or tangentially cut surfaces of stem segments, maximal PWN migration speed was estimated to be faster through cortical resin canals and xylem axial resin canals vertically (>6.7 and <2.3 mm/h, respectively) than through cortical tissues both vertically and horizontally (<1.2 and <0.2 mm/h). To examine whether PWNs in cortical resin canals could invade surrounding tissues, segments in which PWNs resided only in cortical resin canals were prepared by removing the top portion 6 h after inoculation. Additional incubation of such segments caused extended PWN distribution to xylem axial resin canals and then to other tissues. A similar experiment with top portions of girdled segments removed 12 h after inoculation also showed extended PWN distribution from xylem axial resin canals and pith to cortical resin canals and then to other tissues. These results provided direct evidence that PWNs have the ability to migrate from cortical resin canals and xylem axial resin canals to other tissues.     

松材线虫病致病机理的研究进展

该文对松材线虫病的致病机制的研究进行了概述。目前对松材线虫病的病原有两种看法，一种认为松材线虫是惟一病原，另一种认为病原为松材线虫和细菌两种生物。对于松材线虫的致病机理，目前存在3种观点。第1种观点认为松材线虫的酶使松树薄壁细胞的细胞壁和细胞膜遭到破坏，树脂不正常地从树脂道中渗漏并扩散到相邻的管胞中，使水分输导受阻，导致萎蔫。第2种观点认为松树感染了松材线虫后，木质部内挥发性萜烯类物质的含量增加，这些物质进入管胞在管胞中形成空洞，致使水分输导受阻。第3种观点认为松树感染松材线虫后，体内产生有毒物质，这些物质使松树萎蔫。     

越南松树枯死病症状及原因初步研究

为查明越南松树枯死的原因,对越南南部的林同省,中部的承天-顺化省,北部的广宁省的思茅松、马尾松和南亚松枯死症状和原因进行了调查,分别从枯死、濒死、健康松树木质部中抽取52份样品,用于线虫分离镜检。调查发现松树在感病后,树冠部分针叶失去光泽,逐渐褪绿变黄,进而褐红干枯,最后整个树冠变为褐色或红褐色,全株枯死,针叶下垂且当年不落;随着病程的发展,松脂分泌逐渐减少,直至停止;树干上有天牛产卵刻槽,死亡的松树上有天牛的羽化孔。在抽取的松树样品中分离鉴定到了泰国伞滑刃线虫(Bursaphelenchus thailandae BrasschBrassch-Bidasak,2002),为病原的确定和防治工作提供初步的依据。     

Suppression of ectomycorrhizal development in young Pinus thunbergii trees inoculated with Bursaphelenchus xylophilus

In order to study the changes in ectomycorrhizal development during symptom expression of pine wilt disease, root window observations were conducted concurrent with measurements of leaf water potential as well as photosynthetic and transpiration rates of 5‐year‐old Pinus thunbergii trees that were inoculated with the pinewood nematode (PWN) Bursaphelenchus xylophilus. Infected trees were compared with girdled and uninfected control trees. Ectomycorrhizas developed constantly during the experimental period in control trees but did not develop in the girdled trees. Ectomycorrhizal development ceased within 2 weeks in those trees that finally died after PWN infection. In the trees that survived PWN infection, ectomycorrhizal development ceased within 1–4 weeks of inoculation but was resumed thereafter within 3–6 weeks. Ectomycorrhizal development ceased prior to a decrease in both photosynthetic rate and leaf water potential in the inoculated trees.     

An inoculation experiment of Japanese <Emphasis Type="Italic">Bursaphelenchus</Emphasis> nematodes on Japanese black and red pine, <Emphasis Type="Italic">Pinus thunbergii</Emphasis> and <Emphasis Type="Italic">P. densiflora</Emphasis>

The pinewood nematode (PWN) Bursaphelenchus xylophilus is an invasive pathogen that was introduced from North America to Asian countries and Portugal and is devastating native pine forests. Some native European and Asian Bursaphelenchus nematodes also have weak to moderate pathogenicity to native pine species. To evaluate the potential risk of native Bursaphelenchus species, we inoculated ten Japanese Bursaphelenchus species into native pine species (the dominant forest species) in Japan, and evaluated their pathogenicity using mortality and tracheal tissue damage as indices. Inoculation was conducted on August 3, 2007, and the symptoms were observed every 2 weeks until February 1, 2008. None of the inoculated trees, excluding the pathogenic PWN inoculated control, showed external disease symptoms; however, four species [a less pathogenic PWN isolate, B. luxuriosae, Bursaphelenchus sp. NK215 (undescribed), and NK224 (undescribed)] caused tracheal tissue damage in inoculated seedlings and showed weak pathogenicity. Therefore, we conclude that there are some potentially pathogenic native species of nematodes distributed in Japan. Interestingly, two of these weakly pathogenic species, B. luxuriosae and NK215, are not associated with Pinaceae trees, suggesting that nematode pathogenicity may be a pre-adaptive character. More experimental studies under different conditions are necessary to accurately evaluate the potential risk of these pathogens.