Efeito alelopático de Solanum paniculatum para o controle sustentável da planta daninha Leucaena leucocephala

Abstract

Despite advances in agriculture, productivity losses still occur due to the presence of invasive plants, which represent a major obstacle to agricultural production. Based on this assumption, the objective of this study was to evaluate the allelopathic potential of the crude extract and fractions of Solanum paniculatum, compared to glyphosate, on Leucaena leucocephala. The leaves of S. paniculatum were collected in the municipality of Anapurus-MA and identified in the CCAA/UFMA Herbarium under voucher no. 5399. The material was dried, crushed, and subjected to extraction. Two hundred grams of leaves were used in 99.5% ethanol and water, subjected to percolation for 30 days. The preparation of the crude extract and fractions was carried out at the Natural Products Chemistry Laboratory (LQPN/CAMQ/UFMA), followed by chemical characterization. L. leucocephala was used as the recipient plant, testing concentrations of 2% and 5%. Bioassays of bioherbicidal potential were conducted in a completely randomized design (CRD), with four treatments (including positive and negative controls) in four replicates. Statistical analysis was performed using ANOVA, followed by Tukey's test (5%), using InfoStat® (2010) and Excel® (2019) software for data tabulation and interpretation. The study evaluated the allelopathic potential of Solanum paniculatum on Leucaena leucocephala from the crude hydroalcoholic extract (EBH) and its fractions. The EBH was the most active, inhibiting 95% of germination at 5%, in addition to reducing radicle growth (76% at 5%) and hypocotyl growth (70% at 5%). Among the fractions, acetate performed best, with 65% inhibition of the radicle at 5% and 66% of the hypocotyl at 5%. The hexane phase stood out at 2%, with 72% inhibition of the radicle, while the aqueous phase was most effective at 1%, inhibiting 56% of the hypocotyl.