Sandy loam soil maintains better physicochemical parameters and more abundant beneficial microbiomes than clay soil in <i>Stevia rebaudiana</i> cultivation

Depending on the texture of soil, different physicochemical and microbiological parameters are characterized, and these characteristics are influenced by crop cultivation. <i>Stevia</i>, a popular zero-calorie sweetener crop, is widely cultivated around the world on various soil textures. Sandy loam and clay soil show great differences in physicochemical and biological parameters and are often used for <i>Stevia</i> cultivation. To understand the effects of <i>Stevia</i> cultivation on soil physicochemical and biological features, we investigated the changes of physicochemical and microbiological parameters in sandy loam and clay soil following <i>Stevia</i> cultivation. This study was carried out through different physiological and biochemical assays and microbiomic analysis. The results indicated that the sandy loam soil had significantly lower pH and higher nutrient content in the rhizosphere and bulk soils after the <i>Stevia</i> cultivation. The sandy loam soil maintained higher bacterial diversity and richness than the clay soil after <i>Stevia</i> harvest. Beneficial bacteria such as <i>Dongia, SWB02</i>, <i>Chryseolinea</i>, <i>Bryobacter</i> and <i>Devosia</i> were enriched in the sandy loam soil; however, bacteria such as <i>RB41</i>, <i>Haliangium</i> and <i>Ramlibacter</i>, which are unfavorable for nutrient accumulation, predominated in clay soil. Redundancy analysis indicated that the variation in the composition of bacterial community was mainly driven by soil pH, organic matter, total nitrogen, available phosphorus, and microbial biomass phosphorus. This study provides a deeper understanding of physicochemical and microbiological changes in different soil textures after <i>Stevia</i> cultivation and guidance on fertilizer management for <i>Stevia</i> rotational cultivation.