Marigold is reported to have antibacterial activity, and effectively protect crops against soil-borne diseases. However, it is not known whether and how tobacco bacterial wilt (TBW) could be mitigated via intercropping with marigold under field conditions. In this study, a field experiment was performed to measure and compare the occurrence of TBW, the soil chemical properties, and soil microbial composition and diversity between a tobacco-marigold intercropping system and a tobacco monocropping system. At 100 days (d) post-transplantation, the incidence ( I ) and disease index ( DI ) for the tobacco-marigold intercropping system were 30.12% and 58.25% lower than that for tobacco monocropping system, respectively. The results showed that Sobs, Shannon and Chao 1 index of soil bacterial communities in the tobacco-marigold intercropping system were 10.34%, 1.41% and 5.13% higher than that in the tobacco monocropping system at 100 d post-transplantation, respectively. It exhibited a higher richness and diversity of soil bacterial communities in the tobacco-marigold intercropping system. The relative abundance of some beneficial genera in tobacco-marigold intercropping system, such as Lysobacter , Burkholderia , Trichoderma , Mortierella , Chaetomium, Penicillium , was 1.50, 1.61, 3.35, 1.67, 4.40 and 4.50 fold higher than that in tobacco monocropping system. The presence of the intercropping system inhibited soil acidification and loss of soil calcium ions. The redundancy analysis (RDA) indicated that soil pH and exchange Ca 2+ were the main environmental factors which seemed to influence the bacterial and fungal community. The results from this study provided valuable insight into the possible mechanisms enhancing soil health in the tobacco-marigold intercropping system.

中文翻译：

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与万寿菊间作促进土壤健康和微生物结构，以帮助减轻烟草青枯病

据报道，万寿菊具有抗菌活性，可有效保护作物免受土传病害的侵害。然而，尚不清楚在田间条件下通过与万寿菊间作是否以及如何减轻烟草青枯病 (TBW)。在这项研究中，进行了田间试验，以测量和比较烟草-万寿菊间作系统和烟草单作系统之间 TBW 的发生、土壤化学性质、土壤微生物组成和多样性。在移栽后100天(d)，烟草-万寿菊间作系统的发病率(I)和病害指数(DI)分别比烟草单作系统低30.12%和58.25%。结果表明，Sobs, 移栽后100 d，烟草-万寿菊间作系统土壤细菌群落的香农指数和Chao 1指数分别比烟草单作系统高10.34%、1.41%和5.13%。它在烟草-万寿菊间作系统中表现出更高的土壤细菌群落丰富度和多样性。烟草-万寿菊间作系统中一些有益菌属的相对丰度比烟草单作系统高1.50、1.61、3.35、1.67、4.40和4.50倍，如溶杆菌属、伯克霍尔德菌属、木霉属、被孢霉属、毛壳菌属、青霉属等。间作系统的存在抑制了土壤酸化和土壤钙离子的流失。冗余分析(RDA)表明土壤pH和交换Ca 2+ 是似乎影响细菌和真菌群落的主要环境因素。这项研究的结果为了解在烟草-万寿菊间作系统中促进土壤健康的可能机制提供了宝贵的见解。