Response of microbial communities in the tobacco phyllosphere under the stress of validamycin

Moyan Guo; Jingrong Hu; Chaoying Jiang; Yi Zhang; Hancheng Wang; Xinghong Zhang; Tom Hsiang; Caihua Shi; Qing Wang; Feng Wang

doi:10.3389/fmicb.2023.1328179

Response of microbial communities in the tobacco phyllosphere under the stress of validamycin

Front Microbiol. 2024 Jan 18:14:1328179. doi: 10.3389/fmicb.2023.1328179. eCollection 2023.

Authors

Moyan Guo^{1

2}, Jingrong Hu³, Chaoying Jiang⁴, Yi Zhang^{2

5}, Hancheng Wang², Xinghong Zhang^{2

5}, Tom Hsiang⁶, Caihua Shi¹, Qing Wang^{1

2}, Feng Wang²

Affiliations

¹ College of Agriculture, Yangtze University, Jingzhou, Hubei, China.
² Guizhou Academy of Tobacco Science, Guiyang, Guizhou, China.
³ Institute of Advanced Agricultural Science, Hubei University of Arts and Science, Xiangyang, Hubei, China.
⁴ Guizhou Tobacco Company of China National Tobacco Company, Guiyang, Guizhou, China.
⁵ College of Agriculture, Guizhou University, Guiyang, Guizhou, China.
⁶ School of Environmental Sciences, University of Guelph, Guelph, ON, Canada.

Abstract

Validamycin, is classified as an environmentally friendly fungicide. It has high efficacy with little associated pollution risk, and it has been used in China on tobacco for many years especially during leaf spot season. To understand changes in microbial communities and functional aspects of the tobacco phyllosphere after exposure to validamycin, the chemical was sprayed on tobacco leaves during brown spot epidemic periods caused by Alternaria alternata, and asymptomatic and symptomatic leaves of tobacco were sampled at different times (0 day before, 5, 10, and 15 days after application). The fungal and bacterial population diversity and structure were revealed using Illumina NovaSeq PE250 high-throughput sequencing technology, and Biolog-ECO technology which analyzes the metabolic differences between samples by using different carbon sources as the sole energy source. The results showed that the microbial community structure of both asymptomatic and symptomatic tobacco leaves changed after the application of valproate, with the microbial community structure of the asymptomatic tobacco leaves being more strongly affected than that of the symptomatic leaves, and the diversity of bacteria being greater than that of fungi. Phyllosphere fungal diversity in asymptomatic leaves increased significantly after application, and bacterial abundance and diversity in both asymptomatic and symptomatic leaves first increased and then decreased. Validamycin treatment effectively reduced the relative abundance of Alternaria, Cladosporium, Kosakonia, and Sphingomonas in leaves showing symptoms of tobacco brown spot, while the relative abundance of Thanatephorus, Pseudomonas, and Massilia increased significantly after application. Furthermore, the ability to metabolize a variety of carbon sources was significantly reduced in both types of leaves after validamycin application, and both types had a weaker ability to metabolize α-Ketobutyric Acid after application. This study reveals phyllosphere micro-ecological changes in symptomatic and asymptomatic tobacco leaves during different periods after validamycin application and the effects on the metabolic capacity of phyllosphere microorganisms. It can provide some basis for exploring the effect of validamycin on the control of tobacco brown spot.

Keywords: high-throughput sequencing; microbial composition; phyllosphere microorganisms; tobacco brown spot; validamycin.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by China National Tobacco Corporation [110202101048(LS-08) and 110202001035(LS-04)], National Natural Science Foundation of China (31960550 and 32160522), the Hundred Level Innovative Talent Foundation of Guizhou Province [GCC(2022)028–1], the Guizhou Science Technology Foundation (ZK[2021]Key036), Guizhou Province Applied Technology Research and Development Funding Post-subsidy Project, and the Guizhou Tobacco Company (2020XM22, 2020XM03). The authors declare that this study received funding from the China National Tobacco Corporation and Guizhou Tobacco Company. The funders were not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication.