Bandopadhyay Sreejata, Liquet Y González José E, Henderson Kelsey B, Anunciado Marife B, Hayes Douglas G, DeBruyn Jennifer M
Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, TN, United States.
Front Microbiol. 2020 Nov 13;11:587074. doi: 10.3389/fmicb.2020.587074. eCollection 2020.
Agricultural plastic mulch films provide a favorable soil microclimate for plant growth, improving crop yields. Biodegradable plastic mulch films (BDMs) have emerged as a sustainable alternative to widely used non-biodegradable polyethylene (PE) films. BDMs are tilled into the soil after use and are expected to biodegrade under field conditions. However, little is known about the microbes involved in biodegradation and the relationships between microbes and plastics in soils. In order to capture the consortium of soil microbes associated with (and thus likely degrading) BDMs, agriculturally-weathered plastics from two locations were studied alongside laboratory enrichment experiments to assess differences in the microbial communities associated with BDMs and PE films. Using a combination of amplicon sequencing and quantitative PCR (qPCR), we observed that agriculturally-weathered plastics hosted an enrichment of fungi and an altered bacterial community composition compared to the surrounding soil. Notably, , , and were enriched on BDMs compared to non-biodegradable PE. In laboratory enrichment cultures, microbial consortia were able to degrade the plastics, and the composition of the microbial communities was influenced by the composition of the BDMs. Our initial characterization of the microbial communities associated with biodegradable plastic mulch films, or the biodegradable "plastisphere," lays the groundwork for understanding biodegradation dynamics of biodegradable plastics in the environment.
农用塑料薄膜为植物生长提供了有利的土壤微气候，提高了作物产量。可生物降解塑料薄膜（BDMs）已成为广泛使用的不可生物降解聚乙烯（PE）薄膜的可持续替代品。BDMs在使用后被翻耕到土壤中，并有望在田间条件下进行生物降解。然而，对于参与生物降解的微生物以及土壤中微生物与塑料之间的关系，我们知之甚少。为了捕获与BDMs相关（因此可能降解BDMs）的土壤微生物群落，我们研究了来自两个地点的农业风化塑料，并进行了实验室富集实验，以评估与BDMs和PE薄膜相关的微生物群落的差异。通过结合扩增子测序和定量PCR（qPCR），我们观察到与周围土壤相比，农业风化塑料上富集了真菌，细菌群落组成也发生了改变。值得注意的是，与不可生物降解的PE相比，BDMs上富集了[具体物种1]、[具体物种2]和[具体物种3]。在实验室富集培养中，微生物群落能够降解塑料，并且微生物群落的组成受BDMs组成的影响。我们对与可生物降解塑料薄膜相关的微生物群落，即可生物降解的“塑料圈”的初步表征，为理解环境中可生物降解塑料的生物降解动态奠定了基础。
