Effect of disease severity on the structure and diversity of the phyllosphere microbial community in tobacco

Meili Sun; Caihua Shi; Yang Huang; Hancheng Wang; Jianjun Li; Liuti Cai; Fei Luo; Ligang Xiang; Feng Wang

doi:10.3389/fmicb.2022.1081576

Effect of disease severity on the structure and diversity of the phyllosphere microbial community in tobacco

Front Microbiol. 2023 Jan 4:13:1081576. doi: 10.3389/fmicb.2022.1081576. eCollection 2022.

Authors

Meili Sun^{1

2}, Caihua Shi^{1

3}, Yang Huang⁴, Hancheng Wang², Jianjun Li⁵, Liuti Cai², Fei Luo⁶, Ligang Xiang¹, Feng Wang²

Affiliations

¹ MARA Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River, College of Agriculture, Yangtze University, Jingzhou, China.
² Guizhou Provincial Academician Workstation of Microbiology and Health, Guizhou Academy of Tobacco Science, Guiyang, China.
³ School of Food Science and Technology & School of Chemical Engineering, Hubei University of Arts and Science, Xiangyang, Hubei, China.
⁴ China Tobacco Sichuan Industrial Corporation Technical Centre, Chengdu, China.
⁵ College of Tropical Crops, Hainan University, Haikou Hainan, China.
⁶ College of Life Science, Yangtze University, Jingzhou, China.

Abstract

Tobacco target spot is a serious fungal disease and it is important to study the similarities and differences between fungal and bacterial community under different disease severities to provide guidance for the biological control of tobacco target spot. In this study, tobacco leaves at disease severity level of 1, 5, 7 and 9 (S1, S5, S7, and S9) were collected, both healthy and diseased leaf tissues for each level were sampled. The community structure and diversity of fungi and bacteria in tobacco leaves with different disease severities were compared using high-throughput sequencing technology. The results indicated that there was a significant differences in the community structure of fungi and bacteria for both healthy and diseased samples depending on the disease severity. In both healthy and diseased tobacco leaves for all four different disease severities, the most dominant fungal phylum was Basidiomycota with a high prevalence of genus Thanatephorus. The relative abundance of Thanatephorus was most found at S9 diseased samples. Proteobacteria represent the most prominent bacterial phylum, with Pseudomonas as predominant genus, followed by Pantoea. The relative abundance of Pseudomonas was most found at S7 healthy samples. In fungal community, the Alpha-diversity of healthy samples was higher than that of diseased samples. In contrast, in bacterial community, the Alpha-diversity of healthy samples was lower than that of diseased samples. LEfSe analysis showed that the most enrich fungal biomarker was Thanatephorus cucumeris in diseased samples. Clostridium disporicum and Ralstonia pickettii were the most enrich bacterial biomarker in healthy samples. FUNGuild analysis showed that the pathotroph mode was the most abundant trophic modes. The relative abundance of pathotroph mode in diseased samples changes insignificantly, but a peak at S5 was observed for healthy samples. PICRUSt analysis showed that most bacterial gene sequences seem to be independent of the disease severity. The results of this study provide scientific references for future studies on tobacco phyllosphere microecology aiming at prevention and control of tobacco target spot.

Keywords: disease severity; high-throughput sequencing; microbial composition; phyllosphere; tobacco target spot.