Abstract
The aim of this study was to evaluate the phytochemical and allelopathic potential of the aqueous extract of Petiveria alliacea leaves on the germination and initial growth of lettuce seedlings (Lactuca sativa L.). Phytochemical analysis was performed using colorimetric and precipitation techniques. To evaluate the allelopathic potential, four concentrations (25%, 50%, 75% and 100%) were stipulated and the lettuce seeds were kept in contact with them for 72 hours. The parameters evaluated were: germination percentage, germination rate index, fresh weight, and seedling length (root and aerial part). The study revealed that Petiveria alliacea has chemicals from 9 different classes, including alkaloids, coumarins, steroids, phenols, flavonoids, saponins, and tannins. The germination percentage was significantly affected by the extracts at the 75% and 100% concentrations. At the highest concentration (100%), the extract resulted in a reduction of 85.10% in the germination percentage. Additionally, all the extract concentrations were able to significantly inhibit the germination rate index, seedling length, and fresh weight. It was concluded that Petiveria alliacea has great potential as a bioherbicide due to its ability to inhibit germination and seedling growth.