白刺链霉菌CT205对南方根结线虫的毒杀作用及盆栽防效

Nematicidal ability on Meloidogyne incognita and pot-plant control effect of Streptomyces albospinus CT205

[目的]检测白刺链霉菌(Streptomyces albospinus)CT205产生的挥发性有机化合物(volatile organic compound,VOC)和非挥发性有机化合物(nonvolatile organic compound,NVOC),并研究其对黄瓜根结线虫病的生防效果。[方法]分别将线虫悬液和新鲜线虫卵悬液与白刺链霉菌CT205发酵上清液共同培养,测定发酵上清液对根结线虫J2s和虫卵的毒杀作用。用气相色谱-质谱(GC-MS)检测CT205产生VOC的主要组分及含量,采用二分平板来检测CT205 VOC杀线虫活性。通过固体发酵制备白刺链霉菌CT205制剂,开展黄瓜盆栽试验测定CT205制剂对黄瓜根结线虫病的生防效果。[结果]CT205发酵上清液对根结线虫J2s具有较强的杀虫活性,24 h时校正死亡率达91.21%;对根结线虫虫卵同样具有较强的抑卵孵化作用,处理时间在72 h后相对抑制率达80%以上。CT205产生的主要VOC有烯烃类、醇类等化合物,能显著抑制根结线虫J2s活性。CT205菌剂可有效降低黄瓜根结线虫病的发病率促进黄瓜植株生长,对黄瓜根结线虫病的防治效果为45.80%。[结论]白刺链霉菌CT205制剂对根结线虫有很好的毒杀作用,对黄瓜根结线虫病具有较好的生防效果。

[Objectives]The nematicidal ability of volatile organic compound(VOC)and nonvolatile organic compound(NVOC)produced by Streptomyces albospinus CT205 were detected and their biocontrol effect on cucumber root-knot nematode was studied. [Methods]Nematode suspension and fresh egg suspension were cocultured with S. albospinus CT205 fermentation supernatant, and the toxicity of fermentation supernatant to root-knot nematode J2s and eggs were measured respectively. The main components and contents of VOC produced by strain CT205 were detected by gas chromatography-mass spectrometer(GC-MS),and the nematicidal activity of CT205 VOC was detected by dichotomy plate. Microbial agent of S. albospinus CT205 was prepared by solid fermentation, and the pot experiment of cucumber was carried out to determine the biocontrol effect of CT205 microbial agent on cucumber root-knot nematodes. [Results]The fermentation supernatant of strain CT205 had strong nematicidal activity against root-knot nematode J2s, with a corrected mortality rate of 91.21% at 24 h. It also had strong inhibitory effect on egg hatching of root-knot nematode, and the relative inhibition rate was more than 80% after 72 h of treatment. The main VOC produced by strain CT205 included olefins, alcohols, naphthalene and other compounds, which could also significantly inhibit root-knot nematode J2s. CT205 microbial agent could effectively reduce the incidence of cucumber root-knot nematode disease while promoting the growth of cucumber plants, with the control effect of 45.80%. [Conclusions]S. albospinus CT205 had good toxicity against root-knot nematode and good biocontrol effect on cucumber root-knot nematode disease.