BACKGROUND The common weeds Echinochloa crus-galli L. and Setaria glauca L. were studied for their sensitivity to aqueous extracts or dry biomass of the following cover crops (CCs): Brassicaceae (Sinapis alba, Raphanus sativus var. Oleiformis, Camellina sativa), Fagopyrum esculentum, and Guizotia abyssinica. RESULTS Treating E. crus-galli with aqueous extracts of mixed CCs or individual Brassica CC significantly reduced germination. Treating S. glauca with aqueous extracts of C. sativa or G. abyssinicia reduced germination. Aqueous extracts of all CCs significantly reduced radicle length of E. crus-galli and S. glauca, with C. sativa and mixed CCs showing the greatest effect. Aqueous extracts of nearly all CCs delayed start and middle germination of E. crus-galli and S. glauca, with S. alba and R. sativus showing the strongest effects. Aqueous extracts of Brassicaceae leaf and flower significantly reduced germination, coleoptile length, radicle length, and seedling biomass of E. crus-galli and S. glauca. Brassicaceae leaves and flowers contained higher phenolics than other tissues. Adding 4 or 8% S. alba and R. sativus dry powder to soil significantly reduced growth of E. crus-galli and S. glauca; even concentrations of 1% measurably slowed growth of E. crus-galli. CONCLUSION Brassicaceae may be allelopathic to S. glauca and E. crus-galli. Aqueous extracts of leaves and flowers showed greater phytotoxic activity than other tissues and also contained more phenolics. Therefore Brassicaceae CCs may be most effective against S. glauca and E. crus-galli if incorporated into soil during their flowering stage. This article is protected by copyright. All rights reserved.

中文翻译：

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黄狗尾草 (Setaria glauca L.) 和稗草 (Echinochloa crus-galli L.) 对覆盖作物的水提取物或干生物量的敏感性

背景研究了常见杂草 Echinochloa crus-galli L. 和 Setaria glauca L. 对以下覆盖作物 (CC) 的水提取物或干生物量的敏感性：十字花科（白白菜、油菜变种、油茶）、 Fagopyrum esculentum 和 Guizotia abyssinica。结果 用混合 CC 或单个芸苔 CC 的水提取物处理 E. crus-galli 显着降低了发芽率。用 C. sativa 或 G. abyssinicia 的水提取物处理 S. glauca 会降低发芽率。所有 CC 的水提取物都显着降低了 E. crus-galli 和 S. glauca 的胚根长度，其中 C. sativa 和混合 CC 显示出最大的效果。几乎所有 CC 的水提取物都延迟了 E. crus-galli 和 S. glauca 的开始和中期萌发，其中 S. alba 和 R. sativus 显示出最强的效果。十字花科叶和花的水提取物显着降低了 E. crus-galli 和 S. glauca 的发芽、胚芽鞘长度、胚根长度和幼苗生物量。十字花科的叶子和花比其他组织含有更高的酚类物质。向土壤中加入4%或8%的S. alba和R. sativus干粉可显着降低E. crus-galli和S. glauca的生长；即使浓度为 1% 也能明显减缓 E. crus-galli 的生长。结论十字花科可能对S. glauca 和E. crus-galli 具有化感作用。叶和花的水提取物显示出比其他组织更大的植物毒性活性，并且还含有更多的酚类物质。因此，十字花科 CCs 可能对 S. glauca 和 E. crus-galli 最有效，如果在它们的开花阶段掺入土壤。本文受版权保护。版权所有。