生物炭对植物土传病害的影响与作用机制研究进展

Research Progress on the Influence and Mechanism of Biochar on Soil-borne Diseases of Plants

生物炭是生物质在缺氧环境下热解而得到的富碳固体材料,具有发达的孔隙结构、较强的吸附能力及丰富的官能团,其作为一种绿色、可再生的新型功能材料,在土壤改良、污染修复和碳封存等方面具有巨大潜力。近年来,有关生物炭应用于农田土壤改良的研究中发现,植物土传病害的发生情况受生物炭影响显著,生物炭对植物土传病害的影响研究逐渐成为农用生物炭研究的热点方向。由土壤病原真菌和细菌引起的土传病害经常给农作物生产造成无可挽回的损失,以往的化学防治方法又常常给生态环境带来沉重负担,且随着病原微生物的不断演化,常规化学药剂防治效果越来越难以令人满意。植物土传病害严重威胁土壤-植物系统健康和农业可持续发展,过量使用化学药品防控病害存在污染风险,也是病原体产生耐药性的主要原因。本研究从生物炭影响病原微生物的数量和生长代谢、诱导增强植物全系统防御能力以及改善土壤环境等方面,探讨了生物炭抑制土传病害病原微生物的机理。生物炭能够增强植物养分吸收,提高寄主系统抗性,改变土壤微生物群落和功能,减少对抗性和植物毒性化合物,建立健康的植物根际-土壤防御系统,进而减少病原体种群,降低土传病害发病率。生物炭与土壤、植物和病原微生物之间相互作用,很难确定一个单独的因子来解释生物炭对土传病害的影响,还需要更多的实验数据支撑。上述生物炭抗病机制间是否相互独立或者存在协同效应,亟待进一步研究。

Biochar is a carbon-rich solid material obtained by pyrolysis of biomass in an anoxic environment.It has developed pore structure,strong adsorption capacity and rich functional groups.As a new green and renewable functional material,biochar has great potential in soil improvement,pollution remediation and carbon sequestration.In addition,in recent years,studies on the application of biochar in farmland soil improvement have found that the occurrence of soil-borne diseases of plants is significantly affected by biochar,and the influence of biochar on soil-borne plant diseases has gradually become a hot topic in agricultural biochar research.Soil-borne diseases caused by soil pathogenic fungi and bacteria often cause irreparable losses to crop production,and the previous chemical control methods often bring serious burden to the ecological environment.With the continuous evolution of pathogenic microorganisms,the control effect of conventional chemical agents is increasingly difficult to be satisfied.Soil-borne diseases of plants pose a serious threat to the health of soil-plant systems and sustainable development of agriculture.Excessive use of chemical drugs for disease control poses a risk of contamination,which is also the main reason for drug resistance of pathogens.In this study,we explored the mechanism of biochar inhibition of soil-borne disease pathogenic microorganisms from the aspects of influencing the number and growth metabolism of pathogenic microorganisms,inducing and enhancing the whole system defense ability of plants,and improving the soil environment.Biochar can enhance plant nutrient uptake,improve host system resistance,change soil microbial communities and functions,reduce antagonistic and phytotoxic compounds,establish a healthy plant rhizosphere soil defense system,thus reducing pathogen populations and reducing the incidence of soil-borne diseases.It is difficult to determine a single factor to explain the effect of biochar on soil-borne diseases due to the interaction between biochar and soil,plants and pathogenic microorganisms,and more experimental data are needed.Whether these biochar resistance mechanisms are independent or synergistic needs to be further studied.