Invasive plant species can inhibit the growth of native plants by competing for resources as well as by secreting allelochemicals. Indigobush (Amorpha fruticosa L.), a deciduous shrub adaptable to a wide range of environmental conditions, was introduced into Europe as a decorative and valuable honey plant. In this study, we assayed the phytotoxic effect of aqueous leaf extracts (1, 3 and 5%) obtained from A. fruticosa leaves on seed germination and seedling growth of four important agricultural species (Trifolium pratense L. [cultivar “VIVA”], Medicago sativa L. [cultivar OS‐100], Helianthus annuus L. [hybrid “Matej”] and Triticum aestivum L. [cultivar OS‐Olimpija]). Five parameters were analyzed: germination percentage, mean germination time, germination index, fresh weight of seedling root and shoot. The phytotoxicity of A. fruticosa leaf extract was compared to that of juglone, a strong allelochemical that is known to inhibit growth of numerous plant species. The results demonstrate that A. fruticosa phytotoxicity is dependent on both the plant species tested and leaf extract concentration, with higher concentration extracts having stronger phytotoxicity. The highest concentration (5%) leaf extract caused similar inhibition of seed germination and seedling growth to that of juglone. The results of this study suggest that the rapid invasion of A. fruticosa in agricultural areas may have a negative impact on growth and yield of valuable forage and agricultural crops.

中文翻译：

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入侵种金露紫对草料和农作物发芽和早期生长的植物毒性作用

入侵植物可以通过竞争资源以及分泌化感物质来抑制天然植物的生长。Indigobush（Amorpha fruticosa L.）是一种适应多种环境条件的落叶灌木，已作为装饰性和有价值的蜂蜜植物传入欧洲。在这项研究中，我们分析了从A获得的水叶提取物（1、3和5％）的植物毒性作用。紫苏叶对四种重要农业品种（白三叶（Trifolium pratense L. [品种“ VIVA”），苜蓿（Medicago sativa L. [品种OS-100]，向日葵[L.hybrid“ Matej”和普通小麦）的种子萌发和幼苗生长。L. [品种OS-Olimpija]。分析了五个参数：发芽率，平均发芽时间，发芽指数，幼苗根和茎的鲜重。A的植物毒性。紫穗槐叶提取物相比，胡桃醌，是已知许多植物物种的抑制生长强烈化感的。结果表明，一。金黄色葡萄球菌的植物毒性取决于所测试的植物种类和叶提取物的浓度，较高浓度的提取物具有较强的植物毒性。最高浓度（5％）的叶提取物对种子发芽和幼苗生长的抑制作用与胡桃木类似。这项研究的结果表明A的快速入侵。农业地区的金露梅可能对宝贵的饲料和农作物的生长和产量产生负面影响。