Effects on Rhizosphere Soil Microenvironment and Growth Development of Plants Under Tobacco-Garlic Intercropping

As the mechanism of the soil-fungi -plant interaction under the tobacco intercropping model is unclear, and the contribution of this triple interaction to tobacco plant growth is still difficult to predict, so, in this paper, Illumina high-throughput sequencing technology was used to analyze the effects of monoculture (CK) and intercropping with garlic (T1 and T2 treatments) on rhizosphere soil nutrients, enzyme activities, fungal community, tobacco plant growth, and to evaluate the regulation of rhizosphere soil microenvironment and plant productivity on intercropping. The results showed that intercropping significantly increased the nutrient, enzyme activity, fungal community diversity of rhizosphere soil and tobacco plant biomass. Although the dominant fungi in each treatment were the same at the gate level, the distribution ratio of dominant fungi was different. Correlation analysis showed that Ascomycota was positively correlated with all the nutrient and enzyme activity indexes, and the nutrient and enzyme activity indexes were positively correlated with the tobacco plants growth, which strongly indicated that the soil microenvironment under intercropping had a potential effect on the production performance of tobacco plants. In conclusion, tobacco intercropping not only increased the plants biomass, significantly improved the nutrients and enzyme activities of rhizosphere soil, optimized the composition and diversity of fungal community, which may be the result of soil-fungi-plant interaction. 由于在烤烟间作种植模式下土壤-真菌-植物相互作用的机制尚不清楚，且这种三重相互作用对烟株生长的贡献仍难以预测，因此本文采用Illumina高通量测序技术分析了烤烟单作（CK）和与大蒜间作（T1和T2处理）对烟株根际土壤养分、酶活性、真菌群落组成和烟株生长发育的影响，评价了间作对烟株根际土壤微环境和烟株生产力的调控。结果表明：烤烟间作大蒜显著提高了烟株根际土壤的养分、酶活性、真菌群落的多样性和烟株的生物量；虽然各个处理在门水平上的优势真菌是一样的，但优势真菌的分布比例有差异。相关性分析表明，Ascomycota与所有的养分和酶活性指标均呈正相关，而养分和酶活性指标又与烟株生长发育呈正相关，这强烈表明间作下的土壤微环境对烟株的生产性能有潜在的作用。综上所述，烤烟间作不仅增加了烟株的生物量、显著提高了根际土壤养分和酶活性、优化了真菌群落的组成和多样性，而这些可能是土壤-真菌-植物三者相互作用的结果。