Soil Quality Lab., Agricultural Science Center, Federal University of Piauí, Teresina, PI Brazil.
Soil Quality Lab., Agricultural Science Center, Federal University of Piauí, Teresina, PI Brazil.
Chemosphere. 2023 Jul;328:138581. doi: 10.1016/j.chemosphere.2023.138581. Epub 2023 Apr 3.
Imazethapyr and flumioxazin are widely recommended herbicides for soybean fields due to their broad-spectrum effects. However, although both herbicides present low persistence, their potential impact on the community of plant growth-promoting bacteria (PGPB) is unclear. To address this gap, this study assessed the short-term effect of imazethapyr, flumioxazin, and their mixture on the PGPB community. Soil samples from soybean fields were treated with these herbicides and incubated for 60 days. We extracted soil DNA at 0, 15, 30, and 60 days and sequenced the 16S rRNA gene. In general, the herbicides presented temporary and short-term effects on PGPB. The relative abundance of Bradyrhizobium increased, while Sphingomonas decreased on the 30th day with the application of all herbicides. Both herbicides increased the potential function of nitrogen fixation at 15th days and decreased at 30th and 60th days of incubation. The proportions of generalists were similar (∼42%) comparing each herbicide and the control, while the proportion of specialists increased (varying from 24.9% to 27.6%) with the application of herbicides. Imazethapyr, flumioxazin and their mixture did not change the complexity and interactions of the PGPB network. In conclusion, this study showed that, in the short term, the application of imazethapyr, flumioxazin, and their mixture, at the recommended field rates, does not negatively affect the community of plant growth-promoting bacteria.
咪唑乙烟酸和氟草烟是广泛推荐用于大豆田的广谱除草剂。然而，尽管这两种除草剂的持久性都较低，但它们对植物促生菌（PGPB）群落的潜在影响尚不清楚。为了解决这一差距，本研究评估了咪草烟、氟草烟及其混合物对 PGPB 群落的短期影响。将这些除草剂施用于大豆田土壤样品中，并培养 60 天。我们在 0、15、30 和 60 天提取土壤 DNA 并对 16S rRNA 基因进行测序。总的来说，除草剂对 PGPB 具有暂时和短期的影响。在所有除草剂处理下，第 30 天 Bradyrhizobium 的相对丰度增加，而 Sphingomonas 的相对丰度减少。两种除草剂均在第 15 天增加了固氮的潜在功能，而在第 30 天和第 60 天则减少了固氮的潜在功能。与对照相比，每种除草剂和对照的通才比例相似（约 42%），而专家的比例在除草剂处理下增加（从 24.9%到 27.6%不等）。咪唑乙烟酸、氟草烟及其混合物没有改变 PGPB 网络的复杂性和相互作用。总之，本研究表明，在短期内，以推荐田间用量施用咪草烟、氟草烟及其混合物不会对植物促生菌群落产生负面影响。
