Crop allelopathy is a useful tool in integrated weed suppression. Although the abiotic stresses affect the produced secondary metabolites, the impact of soil salinity on crop allelopathic potential under field conditions has not been investigated. So, the effect of soil salinity on the allelopathic activity of 18 allelopathic barley ( Hordeum vulgare L.) varieties was investigated. The allelopathy of barley grown on saline and non-saline soils was investigated during a 2-year field experiment using the Perlite-based bioassay with rigid ryegrass ( Lolium rigidum L.) as plant indicator. The two main allelopathic substances in barley, gramine and hordenine, were determined using the high-performance liquid chromatography with tandem mass spectrometry. The results indicated that rigid ryegrass germination and root length were adversely affected by the barley aqueous extracts. The secondary metabolite gramine was detected in greater concentrations than those of hordenine. For most barley varieties, soil salinity reduced the phytotoxicity of aqueous extracts, as well as the concentration of gramine. However, gramine and hordenine were not highly correlated with the barley extract phytotoxicity, indicating the possible involvement of other allelopathic substances. In conclusion, the barley allelopathic potential probably decreases in soils with high salinity.

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土壤盐分对大麦化感潜力和主要次生代谢产物禾本科和大麦碱的影响

作物化感作用是综合杂草抑制的有用工具。尽管非生物胁迫会影响产生的次生代谢物，但尚未研究土壤盐分对田间条件下作物化感潜力的影响。因此，研究了土壤盐分对18个化感大麦（Hordeum vulgare L.）品种化感活性的影响。在为期 2 年的田间试验中，使用基于珍珠岩的生物测定法以硬质黑麦草 (Lolium 刚玉 L.) 作为植物指示剂，研究了生长在盐渍和非盐渍土壤上的大麦的化感作用。大麦中的两种主要化感物质，禾本科和大麦，使用高效液相色谱串联质谱法测定。结果表明，大麦水提物对硬黑麦草发芽和根长有不利影响。次生代谢产物禾本科的检测浓度高于大麦碱的浓度。对于大多数大麦品种，土壤盐分降低了水提物的植物毒性以及禾本科的浓度。然而，禾本科和大麦碱与大麦提取物的植物毒性不高度相关，表明可能涉及其他化感物质。总之，大麦化感作用可能在高盐度土壤中降低。以及禾本科的浓度。然而，禾本科和大麦碱与大麦提取物的植物毒性不高度相关，表明可能涉及其他化感物质。总之，大麦化感作用可能在高盐度土壤中降低。以及禾本科的浓度。然而，禾本科和大麦碱与大麦提取物的植物毒性不高度相关，表明可能涉及其他化感物质。总之，大麦化感作用可能在高盐度土壤中降低。