Avaliação do potencial alelopático de resíduos foliares do Algodão de Seda sobre Picao-preto e Desmódio.

Abstract

Allelopathy is addressed to the capability of plant species to interfer on the metabolism of another plant, by the releasing of chemical compounds in the environment. The aiming of this work was determinate the allelopathic influence of leaf residues of Calotropis procera in the germination and initial growth of Desmodium tortuosum and Bidens pilosa seedlings. For this, it was developed in laboratory one trial with two treatments, with and without addiction of leaf residues in substrate with seeds of two receiver species. The leaves were dried in oven, subsequently grinded and the powder was used as cover in the substrate with seeds. In the trials were used five replications of 4, 8 and 12 seeds distributed in gerbox with washed sand moisture with distilled water. The germination percentage (PG) and germination velocity (VG), germination velocity index (IVG), length and biomass of aerial and root of Desmodium tortuosum and Bidens pilosa seedlings were measured. The treatments that received the residues showed any germination for all tested plant species. The data exhibited here are concerned to the control treatments. New trials should be conducted to determine whether the results were caused by allelopathic action or mechanical impedance.