Screening endophyte is the most important but also difficult to achieve a successful application in endophyte assisted phytoremediation process. Traditional screening procedure faced certain limitations including long time, difficulty in ascertaining the optimum strain and insignificant promotion efficiency of the selected strain in application. In this study, a novel endophyte screening method was established using microfluidic technology, realizing the real time observation of plant root phenotyping and allowing simultaneous incubation of different endophyte-plant systems. Using this method within two weeks, showed that endophyte Bacillus paramycoides (PE1), which possessed the best capability to improve phytoremediation efficiency from hyperaccumulator P. acinosa was successfully screened by evaluating root growth rate and effluent heavy metal (HM) concentration. PE1 increased root growth rate by 54.31 % and reduced the Cd concentration of chip effluent by 46.33 %. The results were verified by pot experiment, which showed that with PE1 inoculation, the biomass of P. acinosa promoted 42.50 % and Cd removal efficiency increased 55.49 %. Besides, significant and positive correlations were observed among the phytoremediation indicators obtained from microfluidic and traditional method, indicating the feasibility of microfluidic method. Our research provided a new and efficient method for endophyte screening, which could give a better understanding of endophyte assisted phytoremediation technology of HM contaminated soil.

内生菌的筛选是内生菌辅助植物修复过程中最重要但也是最难实现成功应用的一个环节。传统的筛选程序面临一定的局限性，包括时间长、难以确定最佳菌株以及所选菌株在应用中的推广效率不高。本研究利用微流控技术建立了一种新的内生菌筛选方法，实现了对植物根系表型的实时观察，并允许不同内生菌-植物系统同时培养。在两周内使用这种方法，表明内生菌副真菌芽孢杆菌(PE1) 具有提高超积累型P. acinosa植物修复效率的最佳能力通过评估根系生长速度和出水重金属 (HM) 浓度，成功筛选了 。PE1 使根系生长速度提高了 54.31 %，并使木片流出物中的 Cd 浓度降低了 46.33 %。结果经盆栽试验验证，表明接种PE1后，P. acinosa的生物量提高了42.50%，Cd去除效率提高了55.49%。此外，微流控与传统方法获得的植物修复指标之间存在显着正相关，表明微流控方法的可行性。我们的研究为内生菌筛选提供了一种新的有效方法，可以更好地了解内生菌辅助植物修复HM污染土壤的技术。