Biochar Application Alleviated Negative Plant-Soil Feedback by Modifying Soil Microbiome

Abstract

Negative plant-soil feedback (NPSF) frequently cause replant failure in agricultural ecosystems, which has been restricting the sustainable development of agriculture. Biochar application has appealing effects on soil improvement and potential capacity to affect NPSF, but the process is poorly understood. Here, our study demonstrated that biochar amendment can effectively alleviate the NPSF and this biochar effect is strongly linked to soil microorganism in a sanqi (Panax notoginseng) production system. High-throughput sequencing showed that the bacterial and fungal communities were altered with biochar amendment, and bacterial community is more sensitive to biochar amendment than the fungal community. Biochar amendment significantly increased the soil bacterial diversity, but the fungal diversity was not significantly different between biochar-amended and non-amended soils. Moreover, we found that biochar amendment significantly increased the soil pH, electrical conductivity, organic matter, available phosphorus, available potassium, and C/N ratio. The correlation analysis showed that these increased soil chemical variables have a significantly positive correlation with the bacterial diversity. Further analysis of the soil microbial composition demonstrated that biochar soil amendment enriched the beneficial bacterium Bacillus and Lysobacter but suppressed pathogens Fusarium and Ilyonectria. In addition, we verified that biochar had no direct effect on the pathogen Fusarium solani, but can directly enrich biocontrol bacterium Bacillus subtilis. In short, biochar application can mitigate NPSF is mostly due to the fact that biochar soil amendment modified the soil microbiome, especially inhibited pathogens by enriching beneficial bacterium with antagonistic activity against pathogen.

Regular Biochar and Bacteria-Inoculated Biochar Alter the Composition of the Microbial Community in the Soil of a Chinese Fir Plantation

“…In this study, biochar amendment significantly increased the fungal community diversity and significantly decreased the bacterial community diversity in bulk soil (Figure 2)-contrarily to many earlier observations [26,[62][63][64]. This may be related to the changes of chemical properties induced by biochar amendment, as soil properties play more important roles in modifying the bacterial community diversity than fungal community diversity [65]. However, in our research, biochar did not have a significant impact on the soil's chemical properties (Table 2).…”

Effects of biochar on waterlogging and the associated change in micro-ecological environment of maize rhizosphere soil in saline-alkali land

“…Simultaneously, biochar addition improved soil chemical properties, reduced saline-alkali soil pH, and increased soil SOC, AN, and AP. The results of a study by Wang et al (2020) are consistent with findings where biochar promotes soil chemical properties, and these increased soil chemical variables have a significant correlation with soil microorganisms. The relative abundances of soil bacteria in different phyla demonstrated sensitive responses to biochar addition.…”

Biochar-Enhanced Resistance to Botrytis cinerea in Strawberry Fruits (But Not Leaves) Is Associated With Changes in the Rhizosphere Microbiome

“…Symptoms of airborne diseases caused by pathogens, such as Botrytis cinerea , Colletotrichum acutatum , Podosphaera aphanis , and Leveillula taurica ( Elad et al, 2010 ; Meller Harel et al, 2012 ; De Tender et al, 2016a , b ), as well as soilborne pathogens, such as Pythium , parasitic nematodes, and Fusarium oxysporum ( Huang et al, 2015 ; Frenkel et al, 2017 ; Jaiswal et al, 2018 , 2020 ), are reduced on the application of biochar to the growing media or soil. No direct toxic effect of biochar on pathogens has been reported (e.g., Huang et al, 2015 ; Wang et al, 2020 ), indicating that other mechanisms play a role in disease suppression.…”