The purpose of this study was to elucidate how micro/nanobubble-aerated drip irrigation affects the rhizosphere soil and root endophytic bacterial communities of crops grown in saline soil and to explore the microecological mechanism through which this irrigation promotes crop growth under these conditions. This study investigated the responses of root system architecture, the root zone soil microenvironment, and the rhizosphere soil and root endophytic bacterial communities to micro/nanobubble-aerated drip irrigation at different dissolved oxygen (DO) concentrations (5, 15, and 30 mg·L, denoted DO, DO and DO, respectively). Additionally, this study analyzed the changes in the root-soil interdomain bacterial community network as well as their relationships with root system architecture, the root zone soil microenvironment, and tomato yield. The results showed that the soil available nitrogen concentration and available phosphorus concentration in DO were 1.54 and 1.78 times greater than those in the noncultivated soil used as a control (CK); the mean diameter of the root system was 72.35% and 27.85% greater than that under DO and DO, respectively; the root volume was 129.64% and 203.14% greater than that under DO and DO, respectively; and the Shannon index and the number of characteristic species (genus level) of rhizosphere soil bacterial communities increased significantly. The root microenvironment created by DO was conducive to enhancing the metabolism of bacterial communities in the root-soil continuum and promoting tomato growth. The tomato yield was 56.11% and 14.09% greater than that under DO and DO, respectively. Compared to the CK treatment, the DO treatment had 3.86 and 4.66 times greater soil available nitrogen and phosphorus concentrations, respectively, and significantly greater root length and number of forks on the tomato root system, ACE index of the root endophytic bacterial community, and relative abundance of the root endophytic bacterium . These changes also promoted tomato growth, with the yield of tomato plants under DO being 36.82% greater than that under DO. In general, in mildly saline soil under full irrigation, micro/nanobubble-aerated drip irrigation with different DO concentrations significantly affected the soil microenvironment in the tomato root zone and the root system architecture, resulting in differences in the composition and metabolic functions of the rhizosphere soil and root endophytic bacterial communities, which regulated tomato yield. This study provides a reference for promoting crop production in saline soil by regulating crop rhizosphere soil and root endophytic bacterial communities.

中文翻译：

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微/纳米气泡滴灌通过改变细菌群落影响盐渍土微环境和番茄生长

本研究的目的是阐明微纳米气泡滴灌如何影响盐渍土作物的根际土壤和根内生细菌群落，并探讨微纳米气泡滴灌促进作物生长的微生态机制。本研究探讨了根系结构、根区土壤微环境、根际土壤和根内生细菌群落对不同溶解氧（DO）浓度（5、15和30mg·微纳气泡滴灌）的响应。 L，分别表示为 DO、DO 和 DO）。此外，本研究还分析了根-土壤域间细菌群落网络的变化及其与根系结构、根区土壤微环境和番茄产量的关系。结果表明，土壤速效氮浓度和速效磷浓度DO分别是对照土壤（CK）的1.54倍和1.78倍；根系平均直径分别比DO和DO处理下大72.35%和27.85%；根体积比DO和DO处理下分别增加129.64%和203.14%；根际土壤细菌群落香农指数和特征种（属级）数量显着增加。DO创造的根部微环境有利于增强根-土连续体中细菌群落的代谢，促进番茄生长。番茄产量比DO和DO处理分别增产56.11%和14.09%。与CK处理相比，DO处理的土壤速效氮和速效磷浓度分别提高了3.86倍和4.66倍，番茄根系的根长和分叉数、根内生细菌群落的ACE指数和相对值均显着增加。根部内生细菌的丰度。这些变化也促进了番茄的生长，DO处理下番茄植株的产量比DO处理下的番茄植株产量高出36.82%。总体而言，在充分灌溉的弱盐渍土中，不同DO浓度的微纳米气泡滴灌显着影响番茄根区土壤微环境和根系结构，导致根际组成和代谢功能的差异。土壤和根内生细菌群落，调节番茄产量。本研究为通过调控作物根际土壤和根内生细菌群落促进盐渍土作物增产提供参考。