Soil suppressiveness can reduce the damage by plant parasitic nematodes (PPN) in agricultural soils and is conveyed by the activity of soil microorganisms. While natural suppressiveness has been reported, it is still poorly understood if soil suppressiveness can be elicited by manipulating the soil microbial community. In the present study we assessed the number of the Pratylenchus penetrans (Pp) and the bacterial and fungal community composition over 7 years in a long-term soil health experiment. The field experiment consisted of an organic and conventional agricultural land management system and three soil health treatments (SHT): an untreated control (CT), anaerobic disinfestation (AD) and a combination of marigold cover cropping, compost and chitin amendment (CB). The land management systems were kept continuously, while the soil health treatments were applied only twice in seven years. The microbial community significantly differed between the organic and conventional system, but there was no significant difference in Pp numbers between the two systems. However, both the CB treatment and to a lesser extent the AD treatment reduced Pp numbers and increased yield with the effect being the strongest in the years immediately after the treatment. Accordingly, both the bacterial and fungal community differed significantly between the treatments, the differences being largest in the years after the treatments. Notably, the CB treatment elicited both long-term changes in the microbial community and a reduction of Pp numbers lasting for at least three years. These results indicated that a combination of treatments can lead to an altered soil microbial community in combination with persisting suppressiveness of Pp.

土壤抑制性可以减少农业土壤中植物寄生线虫（PPN）的损害，并通过土壤微生物的活动来传递。尽管已经报道了自然抑制作用，但对于是否可以通过操纵土壤微生物群落来引发土壤抑制作用仍知之甚少。在本研究中，我们通过长期土壤健康实验评估了 7 年多的穿透短体线虫(Pp) 的数量以及细菌和真菌群落组成。田间试验包括有机和常规农业土地管理系统以及三种土壤健康处理（SHT）：未经处理的对照（CT）、厌氧灭虫（AD）以及万寿菊覆盖种植、堆肥和甲壳素改良剂（CB）的组合。土地管理系统持续保留，而土壤健康处理在七年内只进行了两次。有机系统和常规系统之间的微生物群落存在显着差异，但两个系统之间的 Pp 数没有显着差异。然而，CB 处理和 AD 处理（在较小程度上）都降低了 Pp 数量并增加了产量，其效果在处理后的几年中最强。因此，不同处理之间的细菌和真菌群落均存在显着差异，且差异在处理后的几年中最大。值得注意的是，CB 处理引起了微生物群落的长期变化和持续至少三年的 Pp 数量减少。这些结果表明，综合处理可以改变土壤微生物群落，并持续抑制 Pp。