Yang Bingye, Feng Changchun, Jiang Hong, Chen Yulan, Ding Mengjiao, Dai Huaxin, Zhai Zhen, Yang Mengmeng, Liang Taibo, Zhang Yanling
Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China.
Sichuan Tobacco Science Research Institute, Chengdu, China.
Front Microbiol. 2025 Mar 14;16:1496385. doi: 10.3389/fmicb.2025.1496385. eCollection 2025.
As is well known, continuous cropping can lead to a decrease in crop yield and quality. Despite this, continuous cropping remains prevalent in practical agricultural production, particularly in the case of tobacco cultivation, owing to its high economic value. The samples for this study were collected from a flue-cured tobacco planting base located in Huili County, Liangshan Yi Autonomous Prefecture, Sichuan Province, China. After years of continuous planting, the yield of tobacco in this base has significantly decreased. In order to explain the microecological causes of this phenomenon, we collected non-continuous cropping, continuous cropping for 5 years, and continuous cropping for 10 years of tobacco rhizosphere soil, and analyzed the effects of long-term continuous cropping on nutrients, enzyme activities, microbial community structure, and function of tobacco rhizosphere soil. The results showed that with the continuous cropping, the majority nutrients (except for phosphorus and manganese) in rhizosphere soil decreased significantly, and the rhizosphere microbial community structure changed significantly. Correlation network analysis results showed that changes in the rhizosphere microbial community of tobacco were closely related to soil urease, active organic carbon, and available iron content. The results of functional analysis based on microorganisms and genes showed that the rhizosphere microbiota may change the content of soil nutrients through iron_respiration, sulfur_respiration, and Carbon fixation in prokaryotes pathways. The results of the correlation network analysis and the functional analysis mutually confirmed each other, both emphasizing the important role of soil carbon and iron in shaping the structure of the tobacco rhizosphere microbial community. Based on the results of this study, we propose to improve the microbial community structure of tobacco rhizosphere soil by increasing the levels of readily oxidizable organic carbon, available iron, and soil urease activity in the future, so as to alleviate the negative impact of continuous cropping on crop yield. The results of this study provide theoretical support for modifying the rhizosphere microbial environment through nutrient regulation, thereby enhancing plant growth in the context of continuous tobacco cropping.
众所周知，连作会导致作物产量和品质下降。尽管如此，由于其较高的经济价值，连作在实际农业生产中仍然普遍存在，尤其是在烟草种植方面。本研究的样本采集于中国四川省凉山彝族自治州会理县的一个烤烟种植基地。经过多年连作，该基地的烟草产量显著下降。为了解释这一现象的微生态原因，我们采集了非连作、连作5年和连作10年的烟草根际土壤，分析了长期连作对烟草根际土壤养分、酶活性、微生物群落结构和功能的影响。结果表明，随着连作年限的增加，根际土壤中的大多数养分（除磷和锰外）显著下降，根际微生物群落结构发生显著变化。相关性网络分析结果表明，烟草根际微生物群落的变化与土壤脲酶、活性有机碳和有效铁含量密切相关。基于微生物和基因的功能分析结果表明，根际微生物群可能通过铁呼吸、硫呼吸和原核生物中的碳固定途径改变土壤养分含量。相关性网络分析和功能分析结果相互印证，均强调了土壤碳和铁在塑造烟草根际微生物群落结构中的重要作用。基于本研究结果，我们建议未来通过提高易氧化有机碳、有效铁水平和土壤脲酶活性来改善烟草根际土壤微生物群落结构，以减轻连作对作物产量的负面影响。本研究结果为通过养分调控改善根际微生物环境，从而在烟草连作情况下促进植物生长提供了理论支持。
