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ORIGINAL RESEARCH article
Front. Microbiol.
Sec. Microbe and Virus Interactions with Plants
Volume 16 - 2025 | doi: 10.3389/fmicb.2025.1574765
This article is part of the Research Topic Unravelling Microbial Interactions in Plant Health and Disease Dynamics View all 14 articles
The synergistic effects of humic acid, chitosan and Bacillus subtilis on tomato growth and against plant diseases
Provisionally accepted
Cunpu Qiu 1*
Ying Bao 2 Dingding Lü 1 Mengyuan Yan 2 Guilong Li 2 Kai Liu 3 Wei Shiping 4
Meng Wu 2
Zhongpei Li 2- 1 Zhenjiang College, Zhenjiang, China
- 2 State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences (CAS), Nanjing, Jiangsu Province, China
- 3 Xuzhou Vacational College of Bioengineering, Xuzhou, China
- 4 Jiangsu Vocational College of Agriculture and Forestry, Jurong, Jiangsu Province, China
Understanding the effects of bio-antimicrobial materials on plant growth and against diseases and the relevant mechanisms are highly important for sustainable soil use and plant safety production. This study explored the impacts and corresponding mechanisms of the combined utilization of humic acid, chitosan, and Bacillus subtilis (B. subtilis) on tomato growth and diseases occurrence through a greenhouse pot experiment. The plant height, fresh weight, disease index, rhizosphere microbial community, and root exudates composition of tomatoes were determined. With the combined application of humic acid, chitosan and B. subtilis (HBC), the height and fresh weight of tomato plants were significantly increased (P<0.05), and the incidence of plant diseases was decreased by 45.1%. In HBC treatment, the diversity of fungal and bacterial communities was notably enhanced. The relative abundances of Bacillus, Gemmatimonas, Neobacillus, Acinetobacter, Humicola increased, while the relative abundances of Sphingomonas, especially soil-borne plant pathogen Fusarium and Ralstonia, significantly decreased (P < 0.05). Besides the increased diversity of root exudates, the content of phenolic acids, which are allelochemicals related to continuous cropping disorder, decreased. The results of cooccurrence network analysis indicated that the abundances of Eicosanoids, Fatty acids and conjugates, and Flavonoid lycosides compounds in root exudates, which are positively correlated with pathogenic bacteria, decreased in HBC treatment. Results indicated HBCs synergistic effect on tomato growth and disease resistance is related to its regulation of microbial community and root exudates. The study results promote the development of biological control technology and highlight its promising application in plant safety production.
Keywords: Humic acid, Chitosan, Bacillus subtilis, Tomato growth, Plant Diseases
Received: 11 Feb 2025; Accepted: 03 Apr 2025.
Copyright: © 2025 Qiu, Bao, Lü, Yan, Li, Liu, Shiping, Wu and Li. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
Cunpu Qiu, Zhenjiang College, Zhenjiang, China
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