Efeito alelopático de piplartina sobre o desenvolvimento inicial de Capim annoni-2 (Eragrostis plana nees) e leiteiro (Euphorbia heterophylla L.) em experimentos de germinação e crescimento

Abstract

Allelopathy refers to biochemical interactions that occur in plants of different types, including microorganisms, encompassing both beneficial and harmful effects. This study aims to evaluate the allelopathic effects caused by piplartin, which is an amide present in plants from the Piperaceae family, in weeds known as annoni-2 and milk grass, at different concentrations and periods of exposure. The experiment was conducted in Petri and Gerbox dishes, in a controlled growth incubator - BOD (Biochemical Oxygen Demand). During the experiments, the PG (%) (Germination Percentage), TMG (Average Germination Time and IVG (Germination Speed Index) were evaluated for germination. And in growth experiments, the length of the hypocotyl and of the radicle of seedlings subjected to the effects of piplartine at lower concentrations (0, 1, 5, 10, 15, 20) and at higher concentrations (0, 25, 50, 75 and 100 ppm) at different periods. The results revealed greater phytotoxic potential of piplartin with the use of higher concentrations (0, 25, 50, 75 and 100 ppm), affecting both the germination process and plant growth, highlighting the inhibitory effect on the growth of hypocotyls . In experiments on germination and hypocotyl and radicle growth using lower concentrations (0, 1, 5, 10, 15 and 20 ppm) of piplartin, there was generally no or stimulatory effect.