Abstract:

In order to investigate the effect of cotton Verticillium wilt pathogens on soil ecosystem, this paper compared and studied the total numbers, amount of trophic groups and ecological indices of soil nematodes in cotton Verticillium wilt pathogens containing soil with that of control soil in Xinjiang Autonomous Region in 2013. The result indicated that a total of 42 nematode genus were identified in both pathogen infected and control areas, 36 of which were detected in the fungivores infected area, 35 were detected in the control area. The abundance of total nematodes, bacterivores and fungi ores in 0~40 cm depth soil layer were significantly lower (P<0.01) in the pathogen infected area than in the control area, while those of plant parasites and omnivore-predator nematodes had no significant difference between the pathogen infected area and the control area. The relative abundance of plant parasites and omnivore-predator nematodes were increased, while the relative abundance of bacterivores was decreased (P<0.01) in the pathogen infected area. Shannon-Wiener diversity index (H′), evenness (J′) and trophic diversity (TD) indices were increased (P<0.05), while Simpsons dominance index (λ) and nematode channel index were decreased (P<0.05) in the pathogen infected area. Above results indicated that pathogens causing cotton Verticillium wilt disease could change community structure and diversity of soil nematodes.

Key words: cotton field, soil nematode, relative abundance, ecological index

摘要：

为了探讨棉花黄萎病菌对土壤线虫群落结构的影响,对比研究了新疆棉花黄萎病区和对照区土壤线虫总数、各营养类群数量和生态指数之间的差异。结果表明：黄萎病区和对照区共鉴定出土壤线虫属42个,其中黄萎病区36个,对照区35个。黄萎病区0~40 cm土壤线虫总数、食细菌线虫数量、食真菌线虫数量显著低于对照区（P<0.01）,植物寄生线虫和捕食-杂食线虫数量没有显著变化（P>0.05）。从相对丰富度来看,黄萎病区植物寄生线虫和捕食杂食线虫的相对丰富度显著高于对照（P<0.01）,食细菌线虫的相对丰富度显著低于对照（P<0.01）。从生态指数来看,黄萎病区土壤线虫的香农-威纳多样性指数（H′）、均匀度指数（J′）、营养多样性指数（TD）均显著高于对照区（P<0.05）；优势度指数（λ）、通道指数（NCR）均显著低于对照区（P<0.05）。总体而言,棉花黄萎病菌会明显改变土壤线虫的群落结构,对其多样性产生显著影响。

关键词: 棉田, 土壤线虫, 相对丰富度, 生态指数