GERMINATION AND INITIAL GROWTH OF Euphorbia heterophylla L. AND Glycine max L. Merril SEEDLINGS WITH LEAF EXTRACTS OF Salvia officinalis L.

Abstract

Weeds have shown great resistance against intensive use of herbicides. An additional management alternative of the plants would be the use of plants´ allelopathic potentiality for future bioprospection. Current paper assesses the bioactivity of salvia extract (Salvia officinalis L.) on the germination and initial growth of the wild poinsettia (Euphorbia heterophylla L.) and soybean (Glycine max L. Merril). Extract were retrieved from the grinding of fresh and dry leaves at the proportion of 1g to 5mL of distilled water. Treatments comprised crude and diluted extract at 50%. Control group comprised only distilled water. Seeds and plants were exposed to the extracts under controlled conditions in a BOD buffer at 25°C. The variables germination percentage (%G), germination speed index (GSI), growth of main roots and the aerial part, and fresh and dry biomass of the organs were evaluated after seven days. Extracts failed to affect %G of the two species but delayed the process. Growth of the wild poinsettia roots was affected by the two types of crude and diluted extract and the growth of the aerial section was reduced by the fresh leaf extract. The growth of soybean seedlings was stimulated by the extracts. Results show possible allelopathic inhibitory activity of salvia leaves on the growth of wild poinsettia seedlings and enhancement on the growth of soybean seedlings