Using community analysis to explore bacterial indicators for disease suppression of tobacco bacterial wilt

Abstract

Although bacterial communities play important roles in the suppression of pathogenic diseases and crop production, little is known about the bacterial communities associated with bacterial wilt. Based on 16S rRNA gene sequencing, statistical analyses of microbial communities in disease-suppressive and disease-conducive soils from three districts during the vegetation period of tobacco showed that Proteobacteria was the dominant phylum, followed by Acidobacteria. Only samples from September were significantly correlated to disease factors. Fifteen indicators from taxa found in September (1 class, 2 orders, 3 families and 9 genera) were identified in the screen as being associated with disease suppression, and 10 of those were verified for potential disease suppression in March. Kaistobacter appeared to be the genus with the most potential for disease suppression. Elucidating microbially mediated natural disease suppression is fundamental to understanding microecosystem responses to sustainable farming and provides a possible approach for modeling disease-suppressive indicators. Here, using cluster analysis, MRPP testing, LEfSe and specific filters for a Venn diagram, we provide insight into identifying possible indicators of disease suppression of tobacco bacterial wilt.

High abundance of Ralstonia solanacearum changed tomato rhizosphere microbiome and metabolome

“…Only one OTU classified as Kaistobacter was connected to RS in both HRS and LRS samples. Kaistobacter has been reported to be more prevalent in suppressive soils [18,20,23], and it is a potential PGPR group because it can produce hormone [19]. Co-occurrence network analysis indicated that the RS invasion affected rhizosphere microbe networks, furthermore, the Flavisolibacter with negatively correlated to RS is one important hub bacteria in HRS networks.…”

Exploring the key microbial changes in the rhizosphere that affect the occurrence of tobacco root-knot nematodes

“…At the same time, we found that the bacteria Bryobacter and Variibacter, as well as fungi Coniochaeta and Metarhizium, were positively related to soil health. According to related reports, these five types of microorganisms are key microbial groups that affect the occurrence of RKN disease (Liu et al 2016, Cao et al 2015.…”

“…Soil-borne diseases are caused by the imbalance in soil ecosystems, such as changes in planting conditions, changes in climate and environment, and changes in treatment measures; hence, understanding the mutual equilibrium relationship between the original soil microorganisms, and balance of soil ecosystems is the key to prevent the disease from continuing to occur and keep the healthy growth of crops (Liu et al 2016). Microbial imbalances in the "plant-soil-microorganism" ecosystem play an important role in the occurrence of diseases (Classen et al 2016).…”

“…Recent studies have shown that a small class of key groups are present in the rhizosphere microbial community, and they play a leading role in promoting disease occurrence (Berg and Smalla 2009;Liu et al 2016;Berendsen et al 2012;Lawson et al 2019). Therefore, we extracted 16S rRNA and 18S rRNA genes from the total DNA of perennial diseased and perennial healthy tobacco rhizosphere soils to further analyze the rhizosphere microbial composition under natural conditions.…”

The preceding root system drives the composition and function of the rhizosphere microbiome

“…Moreover, a dominant bacterial genus, Kaistobacter, which is associated with disease suppressiveness [43] was less abundant in +DR than in −DR, which indicated a higher chance for plants to be infected by pathogen disease under +DR. Kaistobacter is a member of the bacterial community that responds to the availability of easily degradable C compounds, especially plant root exudates [43,44]. Chickpea rhizosphere under −DR assembled more Kaistobacter than wheat (Fig.…”