Impact of soil heat on reassembly of bacterial communities in the rhizosphere microbiome and plant disease suppression

Abstract

The rhizosphere microbiome offers a range of ecosystem services to the plant, including nutrient acquisition and tolerance to (a)biotic stress. Here, analysing the data by Mendes et al. (2011), we show that short heat disturbances (50 or 80 °C, 1 h) of a soil suppressive to the root pathogenic fungus Rhizoctonia solani caused significant increase in alpha diversity of the rhizobacterial community and led to partial or complete loss of disease protection. A reassembly model is proposed where bacterial families that are heat tolerant and have high growth rates significantly increase in relative abundance after heat disturbance, while temperature-sensitive and slow-growing bacteria have a disadvantage. The results also pointed to a potential role of slow-growing, heat-tolerant bacterial families from Actinobacteria and Acidobacteria phyla in plant disease protection. In conclusion, short heat disturbance of soil results in rearrangement of rhizobacterial communities and this is correlated with changes in the ecosystem service disease suppression.

Comparative Analysis of Rhizosphere Microbiomes of Southern Highbush Blueberry (Vaccinium corymbosum L.), Darrow’s Blueberry (V. darrowii Camp), and Rabbiteye Blueberry (V. virgatum Aiton)

“…The analysis identified members of the Sphingobacteriaceae, Sphingomonadaceae, and Cytophagaceae among rhizobacteria that responded to the presence of pathogens by upregulation of stress-related genes. A follow-up study by van der Voort et al (2016) used heat treatment of soil to examine the contribution of different rhizobacterial taxa to the suppression of R. solani. The authors suggested that different Actinobacteria, including members of the Streptomycetaceae and Mycobacteriaceae, may contribute to the disease protection since their decrease coincided with the loss of pathogen suppression.…”

Responses of Coral-Associated Bacterial Communities to Local and Global Stressors

“…Changes in evenness indicates shifts in microbial species dominance, and evenness has been found to decrease in the rhizosphere with added disturbance (van der Voort et al, 2016). An increase in beta diversity in response to stress may indicate a destabilized microbiome in mammals (Moeller et al, 2013;Zaneveld et al, 2017) with the host being unable to regulate its microbiome.…”

Linking ecology and plant pathology to unravel the importance of soil-borne fungal pathogens in species-rich grasslands

“…(Semi-) natural grasslands are characterized by a high plant species richness (up to 89 species per m 2 (Wilson et al 2012)), containing both monocots and dicots. Interestingly, these plant communities are not static: many plant species show high spatiotemporal dynamics, changing positions within the grassland and fluctuating in abundance over time (Herben et al 1993;Van der Maarel and Sykes 1993). It has been proposed that soil-borne fungal pathogens play an important role in this spatiotemporal species turnover (Olff et al 2000).…”