淡紫拟青霉发酵滤液对大豆胞囊线虫趋化性的影响

Effects of Paecilomyces lilacinus M-14 fermentation filtrate on the affinity between soybean cyst nematode and soybean root

实验室条件下 ,研究了大豆胞囊线虫幼虫对大豆根和根浸出液的趋化性以及淡紫拟青霉代谢产物对其趋化性的影响。结果表明 ,大豆胞囊线虫二龄幼虫 (J2 )对大豆根存在着一定的趋化性 ,而淡紫拟青霉发酵滤液对J2 存在明显的驱避性。在根浸出液、真菌滤液及其混合液剂处理下 ,大豆胞囊线虫J2 在WA平板上靠近处理液的 0～ 1cm区间中分布率存在极显著差异 (P <0 .0 1) ,而加样时间 (液剂与线虫同时放置或提前 2 4h处理 )对其分布率没有显著影响。大豆幼根蘸取滤液后对线虫J2 在该区间的分布与不经处理的幼根差异显著 (P <0 .0 5 ) ,证明淡紫拟青霉发酵滤液可以明显地降低线虫与大豆根的亲和力 。

Effect of fermentation filtrate of Paecilomyces lilacinus M-14 on the attraction of second stage juveniles (J_2) of soybean cyst nematode (SCN) to soybean root was tested on agar plate. The filter paper strips soaking up with soybean roots extract or the fermentation filtrate were place on one side of water agar plate and the SCN J_2 suspension was inoculated on another side of plate at a 3 cm distance. The results showed that SCN J_2 were attracted toward to the soybean root extract and repelled by fermentative filtrate of P. lilacinus M-14 according the distribution rates of SCN J_2 on 0-1 cm area nearby filter paper strips. The second stage juveniles were significantly higher in the area treated by the root extract than that by fungal filtrate or mixture of root extract and fungal filtrate (P<0.01). The same result was obtained by using soybean roots or the roots dipped with M-14 filtrate (P<0.05). There was no significantly difference by placing the treated paper strips or roots at the same time or 24 h before J_2 inoculation. It is deduced that P. lilacinus filtrate can obviously reduce the affinity between soybean cyst nematode and soybean roots, and inhibits SCN J_2 invasion to soybean root intensively.