Metabolomic and metagenomic analyses elucidate the role of intercropping in mitigating continuous cropping challenges in tobacco

Ming Liu; Rujun Xue; Shuangzhen Jin; Kaiyuan Gu; Jie Zhao; Shuyue Guan; Xiaoyu Xie; Jiaen Su; Longchang Wang

doi:10.3389/fpls.2024.1447225

Metabolomic and metagenomic analyses elucidate the role of intercropping in mitigating continuous cropping challenges in tobacco

Front Plant Sci. 2024 Dec 23:15:1447225. doi: 10.3389/fpls.2024.1447225. eCollection 2024.

Authors

Ming Liu^#^{1

2}, Rujun Xue^#³, Shuangzhen Jin², Kaiyuan Gu¹, Jie Zhao¹, Shuyue Guan¹, Xiaoyu Xie¹, Jiaen Su², Longchang Wang¹

Affiliations

¹ College of Agronomy and Biotechnology, Southwest University/Engineering Research Center of South Upland Agriculture, Ministry of Education, Chongqing, China.
² Dali Prefecture Branch of Yunnan Tobacco Company, Dali, Yunnan, China.
³ Weishan City Branch of Yunnan Tobacco Company, Weishan, Yunnan, China.

^# Contributed equally.

Abstract

Introduction: Crop rotation of tobacco with other crops could effectively break the negative impact of continuous tobacco cropping, but the mechanisms of intercropping system effects on tobacco, especially on the rhizosphere, are not clear.

Methods: In this study, we investigated the impact of intercropping system on the diversity and function of tobacco metabolites and microorganisms through metabolomic and metagenomic analyses of the tobacco rhizosphere microenvironment intercropped with maize and soybean.

Results: The results showed that the contents of huperzine b, chlorobenzene, and P-chlorophenylalanine in tobacco rhizosphere soils differed significantly among soybean-tobacco and maize-tobacco intercropping system. Chlorobenzene and P-chlorophenylalanine had the highest relative abundance under the soybean-tobacco intercropping system, and huperzine b had the highest relative abundance in the maize-tobacco cropping system. At the phylum level, the three most dominant strains were the same across all treatments: Proteobacteria, Actinobacteria, and Acidobacteria, with only minor differences in their abundance, with the fourth most abundant strain in both the tobacco monoculture. KEGG enrichment analysis of the tobacco rhizosphere soil microbiome revealed that intercropping significantly increased the abundance of metabolites in the ABC transporters pathway and up-regulated the LivK, LivH, Livg, LivM, and LivF genes of the branched-chain amino acid pathway.

Discussion: Collectively, our results indicate that the intercropping could enhance the activity of Livs to enhance the ABC transport pathway, and thus improve the transmembrane transport ability of tobacco roots, thus reducing the negative impact of continuous tobacco cropping. At the same time, the maize-tobacco intercropping could promote the production and transportation of phenolic acids, flavonoids, and other bioactive substances in the tobacco root system, which could enhance tobacco adaptation capacity to abiotic stress.

Keywords: ABC transporter pathway; crop mixtures; intercropping system; metagenomics; rhizosphere soil; tobacco continuous cropping obstacles.

Grants and funding

The author(s) declare financial support was received for theresearch, authorship, and/or publication of this article. The authors declare that this study received funding from Science and Technology Plan Project of Dali Prefecture Branch of Yunnan Tobacco Company (DLYC2023001, DLYC2022006, 2019530000241016, 2020530000241005). The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article, or the decision to submit it for publication.