Cereal rye (Secale cereale) cover crops supply many agroecosystem services in cropping systems including the provision of allelochemicals for weed suppression. Understanding the distinction between root and shoot relative contributions of these allelochemicals (such as phenolic acids) should provide better insight for residue management following termination of a cereal rye cover crop. A field experiment examining root and shoot contributions of phenolic acids to soil was conducted in 2015 at Beltsville, Maryland. Tissue and soil (0–10 cm) phenolic acid concentrations were analyzed over time using liquid chromatography–mass spectrometry. Cereal rye roots were found to be the primary contributor of phenolic acids to soil. Further, soil phenolic acid concentrations were unaffected by tillage or soil depth. Overall, the phenolic acid concentrations of coumaric > vanillic > 4-hydroxybenzoic acid increased in soils during the first 3–7 days after cereal rye termination and then decreased to initial concentrations after 56 days. Our research forms a basis for future allelopathy research. Specifically, there is a need to understand the contribution of roots to phenolic acid release in soils. Building this body of knowledge will improve our ability to employ allelopathy as part of a multi-tactic weed management system.

中文翻译：

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谷物黑麦释放到土壤中的酚酸覆盖了农作物的分解

谷物黑麦（谷物））覆盖农作物在农作物系统中提供许多农业生态系统服务，包括提供用于抑制杂草的化感物质。了解这些化感物质（例如酚酸）的根和芽相对贡献之间的区别应该为谷物黑麦覆盖作物终止后的残留管理提供更好的见识。2015年，在马里兰州贝尔茨维尔进行了一项实地试验，研究了酚酸对土壤的根系和根系贡献。使用液相色谱-质谱法分析随时间推移的组织和土壤（0-10厘米）酚酸浓度。发现谷物黑麦根是酚酸对土壤的主要贡献者。此外，土壤酚酸浓度不受耕作或土壤深度的影响。总体而言，香豆酸的酚酸浓度> 谷物黑麦终止后的前3-7天，土壤中的香草醛> 4-羟基苯甲酸增加，然后56天后降至初始浓度。我们的研究为将来的化感疗法研究奠定了基础。具体来说，有必要了解根对土壤中酚酸释放的贡献。建立这种知识体系将提高我们将化感作用作为多策略杂草管理系统一部分的能力。