A 3-year field study was conducted to assess effects of two winter cover crops, Elbon rye (Secale cereal L.) and Crimson clover (Trifolium incarnatum L.), under till and no till management, on bacterial community composition in soybean (Glycine max L.) field soils using high-throughput sequencing of the 16S rRNA gene. Effects of tillage and cover crop on bacterial composition at the phylum level were minor, with most significant differences between treatments occurring at finer taxonomic levels. Tilled plots displayed higher levels of Xanthomonadaceae, while cover cropped soils had greater Bradyrhizobium abundances. Functional gene prediction indicated that genes associated with decomposition of C and P compounds, as well as biocontrol agents, were elevated in tilled plots, genes associated with root growth promotion were elevated in cover crop treatments, and nitrate reductase and denitrification genes were elevated in both no till and cover crop plots. While valuable functional insights can be gained from sequence analyses, not all differences observed at the sequencing level will translate into functional differences due to variation in gene expression, and further study is needed to validate which functions can be predicted from sequencing data.

进行了为期3年的田间研究，评估了在不耕作和不耕作的情况下，两种冬季覆盖作物Elbon黑麦（Secale谷物L.）和Crimson三叶草（Trifolium incarnatum L.）对大豆（甘氨酸）细菌群落组成的影响。max L.）田间土壤，使用16S rRNA基因的高通量测序。在门廊水平上，耕作和覆盖作物对细菌组成的影响很小，在较细分类标准下，处理之间的最显着差异。耕作的土地表现出较高的黄原菌科水平，而覆盖的耕作土壤中的根瘤菌含量更高丰富。功能基因预测表明，在耕作地中与C和P化合物分解相关的基因以及生物防治剂均升高，在覆盖作物处理中与促进根系生长相关的基因均升高，而硝酸还原酶和反硝化基因均升高。禁止耕种并覆盖农作物地。尽管可以从序列分析中获得有价值的功能见解，但由于基因表达的差异，并非所有在测序水平上观察到的差异都会转化为功能差异，还需要进一步的研究以验证可以从测序数据中预测哪些功能。