Three ethanol extraction of crude extract were extracted with the liquid-liquid partition method, by toxicity bioassay of PWN, petroleum ether extracts of the root crude ethanol extracts had the highest toxicity to PWN. 3.

About pathogenetic mechanism of PWN there are 3 opinions.

对于松材线虫的致病机理，目前存在3种观点。

Many factors affected the fecundity and reproduction of PWN, and the key environment factors were temperature and humidity.

温度和水分是影响松材线虫繁殖行为的主要外界因子。

The toxin occurred by the tree after the PWN invaded affect the death.

松材线虫入侵松树后，松树体内出现了导致松树死亡的毒素；

Study on Using Wood-rotting Fungi to Treat Stumps of Dead Wood Caused by PWN ( Bursaphelenchus Xylophilus); The Maine woodsman sits on a stump whose rings number centuries of growth.

利用木腐菌处理松材线虫病病死树伐桩的研究缅茵州的伐木人坐在一段有数百年年轮的木桩上。

The inoculation of PWN into the H provenance resulted in the decrease followed by the increase of the ratio of contents of longifolene and trans caryophyllene.

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；

At present, symbiotic or parasitic bacteria were reported to be associated with many plant pathogenic nematodes, but the relationship between PWN and its associated bacteria was not understood.

目前，许多植物病原线虫都报道有伴生细菌，它们之间属于共生或者寄生关系，而松材线虫与其伴生细菌的关系还有待研究。

The resistance of pine to the PWN is evidently different in different species, and the resistance difference among the geographical population depends on the pine species.

在松树对松材线虫的抗性方面，树种之间抗性的差异性较显著，而同种松树不同地理种源之间抗性的差异性的显著程度因树种而异。

It is suggested that 450W ( GGC) light be applied in monitoring population dynamics of JPS and PWN after further test.

因此利用450W高压汞灯监测松墨天牛及松材线虫种群有应用价值，有待进一步试验完善。

The volatile material increased in xylem after the PWN invaded. The blockage of water conduction caused by tracheid cavitation was very important factor causing the death of infected pine trees.

松树感染松材线虫后，木质部内挥发性物质增加，管胞中形成了空洞，致使松树体内水分输导受阻，松树萎蔫死亡。

For moderate resistant pines, P.rigida and P.massoniana, the universal level of latent infection and PWN number in the samples were mid.

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。

There are two ways to change the business processes of rewriting nets based on PWN.

有两种方式可以改变重写网的业务流程：（1）改变PWN的编程函数。

Host plant species had no significant influence on number of PWN transmitted by adults. In course of adults supplementary nutrition, number of PWNs transmitted by adults had no significant difference among most observing records ( eyery other 2 days).

补充营养寄主的种类对松墨天牛成虫传递松材线虫数量影响不显著，松墨天牛成虫在补充营养过程中，每个时间段（2天）所传递的松材线虫数差异不大。

The above results of biogeography provided a reference for PWN quarantine, monitoring and forecast in China.

以上松材线虫的生物地理学研究结果，为我国松材线虫的检疫和、监控和预测提供了参考依据。

The proliferation response of child thymocytes to PHA was far more significant than those to ConA and PWN. This differs from the more pronounced effect of ConA on thymocyte proliferation in mice.

结果表明，小儿胸腺细胞对PHA刺激反应远较对ConA及PWM刺激反应明显，与小鼠胸腺细胞对ConA刺激反应远较对PHA刺激反应明显有所不同。

The models and rules of rewriting nets based on PWN can realize all operations of various changing modes, and can alter the support characteristics, which can compares existing process management technology from the view of systems, of the changes of control flows.

PWN重写网的模型和规则能够实现各种变化模式的所有操作，并且能够改变控制流变化的支持特征。其中，支持特征能够从系统的角度对比现有的过程管理技术。

This indicates that the local biological factors such as vector beetles and blue-stain are the keys to the invasion of PWN. 2.

从而说明了入侵地的媒介天牛和蓝变菌等生物因素是松材线虫入侵的关键因素之一。

When PWN invaded host, most PWN were trapped in the resin canals and then migrated into other tissues after molting.

松材线虫侵入树体后，大多滞留在树脂道，蜕皮变为成虫后再向其它部位迁移。

Pine Wilt Disease ( PWN), a fatal disease to China's pine forest, has killed tens of millions pine trees, causing great economic losses and doing severe damage to the ecological environment.

松材线虫病是我国松林毁灭性病害，已造成数千万松株死亡，发生区经济损失巨大，目前此病害正威胁着南方重点林区及重要风景名胜区松林的安全。

Also spotted on set was Nicole's co-star Milo Ventimiglia looking dapper in a vintage suit.

此外，米洛·文堤米利亚（Milo Ventimiglia）也出现在当天的拍摄现场。

Yet even Mr Buckley, a hard-headed Yorkshireman running a global manufacturer, says the greatest innovations benefit from a sprinkling of hard-to-define pixie dust.

但即便是伯克利这样经营着一家全球制造企业的精明约克郡人，也表示，最伟大的那些创新，是沾了一种难以定义的仙尘的光。