Plants that release molecules affecting other plants are a source of potential bioherbicides. Silver wattle (Acacia dealbata Link), considered invasive worldwide, was found to be phytotoxic to various other plant species. Combining the search for alternative bioherbicides while reducing the spread of this invader by preventing seed formation is a good potential strategy to solve both agricultural and environmental problems. This study aimed to identify nonvolatile compounds from A. dealbata flowers and explore their phytotoxicity on the germination process and seedling and plant growth of lettuce (Lactuca sativa L.), wheat (Triticum aestivum L.), and rigid ryegrass (Lolium rigidum Gaudin). We identified methyl cinnamate and methyl anisate as potential phytotoxins in the extracts, but we used pure commercial molecules to conduct bioassays. Methyl cinnamate showed higher phytotoxicity than methyl anisate and was selected for further bioassays. Methyl cinnamate reduced guaiacol peroxidase activity by 57% and 85% in L. rigidum and lettuce, respectively, and α-amylase by 6% in L. rigidum. This compound also inhibited early stem and radicle growth of dicotyledonous lettuce (60% and 89%, respectively) and monocotyledonous L. rigidum (76% and 87%, respectively), both species having small seeds. However, wheat with a larger seed size was not affected by the phytotoxin. The results obtained indicate a potential bioherbicidal effect for methyl cinnamate, and its application might be useful in wheat crops infested by L. rigidum. We suggest that collecting A. dealbata flowers would prevent Acacia seed formation and thus play a role in invasive pest management, as well as serving as a source of potential herbicides to other species.

中文翻译：

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肉桂酸甲酯商业配方的除草性能，肉桂酸甲酯是侵入性银合欢 (Acacia dealbata) 中的一种天然化合物

释放影响其他植物的分子的植物是潜在的生物除草剂的来源。银荆棘 (金合欢Link) 被认为是世界范围内的入侵物种，被发现对各种其他植物物种具有植物毒性。结合寻找替代生物除草剂，同时通过防止种子形成来减少这种入侵者的传播，是解决农业和环境问题的一个很好的潜在策略。本研究旨在鉴定非挥发性化合物A.dealbata并探讨其对生菜发芽过程和幼苗及植株生长的药害(莴苣L.), 小麦 (小麦L.) 和硬质黑麦草 (黑麦草高丁）。我们将肉桂酸甲酯和茴香酸甲酯鉴定为提取物中潜在的植物毒素，但我们使用纯商业分子进行生物测定。肉桂酸甲酯显示出比茴香酸甲酯更高的植物毒性，并被选择用于进一步的生物测定。肉桂酸甲酯使愈创木酚过氧化物酶活性降低 57% 和 85%刚体乳杆菌和生菜分别，α-淀粉酶降低 6%L.刚性。该化合物还抑制双子叶莴苣（分别为 60% 和 89%）和单子叶莴苣的早期茎和胚根生长刚体乳杆菌（分别为 76% 和 87%），这两个物种都有小种子。然而，具有较大种子大小的小麦不受植物毒素的影响。获得的结果表明肉桂酸甲酯具有潜在的生物除草作用，其应用可能对小麦作物受害刚体乳杆菌. 我们建议收集A.dealbata花会阻止相思种子形成，因此在入侵性害虫管理中发挥作用，以及作为其他物种潜在除草剂的来源。