Plant and soil characteristics affected by the allelopathic pathways of Avena fatua and Lolium temulentum weeds

The potential of the most prevalent weeds should be characterized biologically and chemically in infected soil and crops for sustainable agriculture. Therefore, the allelopathic potential of <i>Avena fatua</i> L. and <i>Lolium temulentum</i> L. weeds were compared via leachates, root exudates, decayed residues in soil, and the decomposition in water pathways. Chemical measurements were taken on wheat (<i>Triticum aestivum</i> L.), and soil decomposed solution. Based on EC₅₀, the allelopathic effect of leachates were higher in aboveground parts than in subterranean parts, influenced by plant parts and concentrations. The root exudates show EC₅₀ by 655.9 μg. ml^-1 for <i>A. fatua</i> and 625.66 μg. ml^-1 for <i>L. temulentum</i>in the seedling biomass fresh weights of <i>T. aestivum</i>. The systematic inhibition by decayed residues was affected by plant types, concentration, and time and correlated with soil parameters and crop performance. The decomposition rate was higher under aerobic conditions than anaerobic conditions, with the inhibition pattern showing the reverse trend. These finding highlight the importance of environmental conditions in mediating allelopathic effects. The highest quantities of phenolic acids determined by LC-ES/MS in decomposed solutions were citric acid, with concentrations of 7.71 and 13.31 μg/ml in <i>A. fatua</i> under aerobic conditions, and coumaric acid, with concentrations of 9.21 and 16.99 μg/ml in <i>L. temulentum</i> under aerobic conditions. The allelopathic potentials of <i>A. fatua</i> and <i>L. temulentum</i> may play a crucial role in <i>T. aestivum</i> crop growth and soil parameters. In general weed residues can suppress crop growth and negatively affect soil parameters based on their quantity and type, therefore they should be managed carefully for sustainable crop production.