AVALIAÇÃO DA INFLUÊNCIA DOS EXTRATOS DE FOLHAS E SEMENTES DE Pterodon emarginatus Vogel, NO CRESCIMENTO E DESENVOLVIMENTO DE Lactuca sativa VARIEDADE CRESPA ITAPUÃ SUPER

Abstract

Allelopathy consists of the release of chemical compounds by certain plant species, capable of positively or negatively interfering with the growth of other plants. In this context, the present study aimed to evaluate the allelopathic potential of leaf and seed extracts of sucupira (Pterodon emarginatus Vogel) on the development of lettuce (Lactuca sativa L.), cultivar Crespa Itapuã Super, grown in a greenhouse at the Instituto Federal Goiano – Campus Posse. The experiment was conducted in a completely randomized design, with nine treatments: four concentrations of leaf extract (200, 400, 800 and 1000 mg/L), four of seed extract in the same proportions, and a control with distilled water, totaling 50 repetitions per treatment. Germination, plant height, leaf length, root length, and fresh mass were evaluated. The data were subjected to analysis of variance (ANOVA), Tukey's test (5%), and multivariate analyses using Principal Component Analysis (PCA) and hierarchical clustering. The germination test indicated high seed viability, with rates between 94% and 100%. The results demonstrated that the extracts showed an effect dependent on concentration and the type of plant material used. Intermediate concentrations (400 mg/L) promoted growth stimulation, reflected in higher values of height, leaf development, and biomass accumulation. On the other hand, higher concentrations and some specific treatments showed an inhibitory effect, mainly on root length and fresh mass, indicating greater sensitivity of the root system to allelopathic compounds. Multivariate analysis explained more than 90% of the total variance and confirmed the distinction between treatments, showing a positive correlation between plant height and weight and differentiated behavior for root length. It is concluded that Pterodon emarginatus has allelopathic potential, and can exert stimulating or inhibitory effects on Lactuca sativa, depending on the concentration applied, standing out as a species of interest for studies focused on sustainable agricultural management.