Efeitos alelopáticos de Tectona grandis L.F. sobre a germinação e desenvolvimento inicial da alface (Lactuca sativa L. F.)

Abstract

The objective of this work was to evaluate the allelopathic effects of aqueous extracts of Tectona grandis L.F. in various concentrations produced from leaves and flowers. The seeds of Lactuca sativa lettuce were used, with the germitest paper moistened with distilled water and the aqueous extracts in concentrations of 100%, 75%, 50%, 25% and as a control (0% distilled water). The extracts were homogeneously deposited on twentyfive seeds evenly distributed in gerbox boxes. The materials used in the experiment were previously sterilized with 70% alcohol. A completely randomized design with four replicates was used and the experiment was carried out under natural conditions of temperature and humidity, and the tests were carried out in the Laboratory of Forest Seeds (Lasf), the experiment was followed for 10 days at the same time and the variables analyzed were %G, IVG, TM and VM. The data were submitted to Analysis of Variance and compared by Tukey test with probability of 5% error. It was observed that there were no significant differences in leaf extracts and flowers with respect to %G, TM and MV, however, in IVG aqueous leaf extract significantly interfered in the highest concentrations (75% and 100%). It was possible to conclude that the species has an allelopathic potential in the IVG, while the flower extracts show that on VM the concentrations 25% and 100% differed statistically.