Soil multitrophic interactions are the keystone of understanding mechanisms of ecological function. In order to test the effect of nematode functional guilds on rice growth and Nilaparvata lugens abundance, a pot experiment was conducted by growing rice with a complete factorial design manipulating microbivores (microbivorous nematodes), herbivores (herbivorous nematodes) and omnivore-carnivores (omnivore-carnivorous nematodes). Results showed that compared with no nematodes, herbivores

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... antly increased rice root biomass (P < 0.05) and total shoot phenolic content (P < 0.05). The microbivores significantly increased N. lugens abundance and significantly reduced root biomass (P < 0.05). Omnivore-carnivores promoted rice shoot growth (P < 0.05), decreased the number of N. lugens (P < 0.05). Higher total phenolic content occurred in treatment receiving all three nematode functional guilds, suggesting stronger potential for insect resistance. In conclusion, organisms at higher trophic levels, such as omnivore-carnivores, could promote plant defense and suppress aboveground herbivory via regulating the herbivores and microbivores. Soil biota managements play central roles in control of trophic level diversity.