生物炭对酚酸胁迫下番茄生长和土壤微生态的影响

Effect of Biochar on Tomato Growth and Soil Microecology Under Phenolic Acid Stress

【目的】明确施用生物炭对酚酸胁迫下"番茄植株-土壤-微生物"体系的调控效应。【方法】通过盆栽试验比较添加生物炭处理对酚酸胁迫下番茄生长和生理指标、番茄产量与品质、土壤理化性质及微生物多样性的影响,并通过冗余分析解析各因素之间的互作机制。【结果】与外源酚酸胁迫处理相比,施用5%生物炭可有效缓解酚酸对番茄植株生长的胁迫作用,提高根系活力和根冠比,番茄单株产量和单果重分别提高15.2%和4.3%,糖酸比增加32.0%。施用生物炭处理与酚酸胁迫处理相比,收获期土壤pH提高0.59个单位,EC值降低21.9%,残余总酚酸质量分数降低25.3%。冗余分析结果表明,生物炭通过改变pH、碱解氮、总氮、总酚酸含量4个主要土壤环境因子,进而促进与番茄产量和品质呈正相关的微生物丰度的增加,抑制与番茄产量和品质呈负相关的微生物丰度。【结论】生物炭可通过改变土壤pH、氮素、总酚酸含量等理化性质,选择性促进或抑制与番茄产量和品质相关的土壤微生物群落丰度,通过根际土壤微生态环境的改变,缓解酚酸类化感物质对番茄植株的胁迫作用,从而达到促生、增产、提质的效果。

【Objective】The study was conducted to clarify the regulation effects of biochar on"tomato-soil-microbial community"system under phenolic acid stress.【Method】Pot experiments were conducted to compare the effects of biochar addition on tomato growth,physiological indices,tomato yield and quality,soil physicochemical properties and soil microbial diversity under phenolic acid stress.Redundancy analysis was used to reveal the interaction mechanism among the above factors.【Result】Compared with the treatment under exogenous phenolic acid stress,the application of 5%biochar could effectively alleviate the stress effect of phenolic acid on tomato plant growth,increase root activity and root-shoot ratio,the single plant yield and average weight of single fruit were increased by 15.2%and 4.3%,and ratio of sugar to acid was increased by 32.0%.Compared with the phenolic acid stress treatment,the application of biochar increased soil pH by 0.59 units,decreased EC value by 21.9%,and the total phenolic acid content was reduced by 25.3%at harvest time.Redundancy analysis results showed that biochar changed the four main soil environmental factors:pH,alkaline nitrogen,total nitrogen,and total phenolic acid contents,then promoted the abundance of microorganisms positively related to tomato yield and quality,and inhibited the abundance of those negatively related to tomato yield and quality.【Conclusion】Generally,biochar addition can selectively promote or inhibit soil microbial community abundance related to tomato yield and quality by changing the soil pH,nitrogen,total phenolic acid content and other physicochemical properties.Through the change of microecological environment of rhizosphere soil,the stress effects of phenolic acid allelochemicals on tomato plants can be alleviated,hence achieving the effects of promoting growth,increasing production and improving quality.