Gugliucci Wanda, Cirillo Valerio, Maggio Albino, Romano Ida, Ventorino Valeria, Pepe Olimpia
Department of Agricultural Sciences, Division of Microbiology, University of Naples Federico II, Naples, Italy.
Department of Agricultural Sciences, Division of Plant Biology and Crop Science, University of Naples Federico II, Naples, Italy.
Front Plant Sci. 2023 Jun 5;14:1180061. doi: 10.3389/fpls.2023.1180061. eCollection 2023.
Industrial wastewater obtained from hydrothermal liquefaction (HTL-WW) of food wastes for biofuels production could represent a source of crop nutrients since it is characterized by a high amount of organic and inorganic compounds. In the present work, the potential use of HTL-WW as irrigation water for industrial crops was investigated. The composition of the HTL-WW was rich in nitrogen, phosphorus, and potassium with high level of organic carbon. A pot experiment with L. plants was conducted using diluted wastewater to reduce the concentration of some chemical elements below the official accepted threshold values. Plants were grown in the greenhouse under controlled conditions for 21 days and irrigated with diluted HTL-WW every 24 hours. Soils and plants were sampled every seven days to evaluate, over time, the effect of wastewater irrigation both on soil microbial populations, through high-throughput sequencing, and plant growth parameters, through the measurement of different biometric indices. Metagenomic results highlighted that, in the HTL-WW treated rhizosphere, the microbial populations shifted their mechanisms of adaptation to the new environmental conditions, establishing a new balance among bacterial and fungal communities. Identification of microbial taxa occurring in the rhizosphere of tobacco plants during the experiment highlighted that the HTL-WW application improved the growth of Micrococcaceae, Nocardiaceae and Nectriaceae, which included key species for denitrification, organic compounds degradation and plant growth promotion. As a result, irrigation with HTL-WW improved the overall performance of tobacco plants which showed higher leaf greenness and increased number of flowers compared to irrigated control plants. Overall, these results demonstrate the potential feasibility of using of HTL-WW in irrigated agriculture.
从用于生物燃料生产的食物垃圾水热液化（HTL）中获得的工业废水（HTL-WW）可能是作物养分的一个来源，因为它含有大量有机和无机化合物。在本研究中，对HTL-WW作为经济作物灌溉水的潜在用途进行了调查。HTL-WW的成分富含氮、磷和钾，有机碳含量高。使用稀释废水进行了L.植物的盆栽试验，以将某些化学元素的浓度降低到官方认可的阈值以下。植物在温室中于受控条件下生长21天，每24小时用稀释的HTL-WW灌溉一次。每七天对土壤和植物进行采样，以便随着时间的推移，通过高通量测序评估废水灌溉对土壤微生物群落的影响，并通过测量不同的生物特征指标评估对植物生长参数的影响。宏基因组学结果表明，在经HTL-WW处理的根际中，微生物群落改变了其对新环境条件的适应机制，在细菌和真菌群落之间建立了新的平衡。对实验期间烟草植物根际中出现的微生物类群的鉴定表明，施用HTL-WW促进了微球菌科、诺卡氏菌科和丛赤壳科的生长，其中包括反硝化、有机化合物降解和促进植物生长的关键物种。结果，与灌溉对照植物相比，用HTL-WW灌溉提高了烟草植物的整体性能，表现为叶片更绿，花朵数量增加。总体而言，这些结果证明了在灌溉农业中使用HTL-WW的潜在可行性。
