Allelopathic Potential of Lavender’s Extract and Coumarin Applied as Pre-Plant Incorporated Into Soil Under Agronomic Conditions

ABSTRACT: This study aimed to further explore that if coumarin and lavender’s extract, similar to greenhouse conditions, are phytotoxic towards some plant species under agronomic conditions. Before planting of maize, coumarin at 0, 250, 500, 1,000, 2,000, and 4,000 g h-1 and lavender’s aqueous extract at 0, 1,000, 2,000, 4,000, 8,000, and 16,000 mL h-1 were applied and incorporated into soil at a 3-5 cm depth. The density and biomass of weeds was significantly reduced by applying both compounds. The inhibition ability was also rate-dependent. Although the density and biomass of maize was also decreased at high rates, this crop showed higher tolerant to both compounds that all weeds.