Apple replant disease (ARD) is a common and destructive disease in apple orchards with long cultivation histories. In the present study, soils from three apple orchards under cultivation for two years (G2), thirty years (G30), and forty years (G40) were used to investigate the key nutritional factors influencing soil bacterial community structure. Changes in nutrient concentrations in the orchard soil entailed reductions in concentrations of medium trace nutrients (magnesium [Mg], manganese, and nickel) and the increase in concentrations of macronutrients (total nitrogen [TN], total phosphorus, total potassium, available phosphorus, and available potassium) and soil organic carbon. As cultivation time was prolonged, bacterial community composition shifted from enrichment with oligotrophic Acidobacteria and plant growth-facilitated Streptomyces to increased abundance of copiotrophic taxa, Bacteroidetes and Firmicutes, and plant-growth-impairing Gemmatimonas, based on 16S rDNA (V4) amplicon sequencing data. In addition, the relative abundances of bacteria associated with fermentation function and the decomposition of some unique compound classes increased, while the relative abundance of bacteria associated with the nitrification function decreased. Among all the nutritional elements tested using distance-based multivariate linear model analysis, Mg and TN influenced community structure the most. The results provide novel insights into the associations between soil nutrients and shifts in microbial community structure under long-term apple orchard soil ecosystems.

苹果再植病（ARD）是苹果园种植历史悠久的常见病害。在本研究中，来自三个苹果园种植两年 (G2)、三十年 (G30) 和四十年 (G40) 的土壤被用来研究影响土壤细菌群落结构的关键营养因素。果园土壤中养分浓度的变化导致中等微量养分（镁 [Mg]、锰和镍）浓度的降低和常量养分（总氮 [TN]、总磷、总钾、有效磷、和有效钾）和土壤有机碳。随着培养时间的延长，细菌群落组成从富集寡营养酸杆菌和促进植物生长的基于 16S rDNA (V4) 扩增子测序数据，链霉菌增加了营养类群、拟杆菌门和厚壁菌门以及阻碍植物生长的Gemmatimonas 的丰度。此外，与发酵功能相关的细菌的相对丰度和一些独特化合物类别的分解增加，而与硝化功能相关的细菌的相对丰度下降。在使用基于距离的多元线性模型分析测试的所有营养元素中，Mg 和 TN 对群落结构的影响最大。结果为长期苹果园土壤生态系统下土壤养分与微生物群落结构变化之间的关联提供了新的见解。