Efeito alelopático de extrato aquoso de piper cf. aduncum l. (PIPERACEAE) na germinação e crescimento de lactuca sativa l. (ASTERACEAE)

Abstract

The allelopathic effects occur through processes in which secondary metabolites of a given plant are released and can influence positively or negatively the development of another plant. 2 In this sense, the family Piperaceae stands out in phytochemical studies. The objective of this work was to identify the allelopathic effects caused by Piper aduncum leaves on germination and growth of lettuce seedlings (Lactuca sativa). In order to obtain the biotestes of germination and growth, the dried leaves in the greenhouse were crushed and weighed so that the extracts were prepared, followed by four concentrations of the aqueous extracts (2.5%, 5%, 7.5% ; 10%) of P. aduncum leaf and a control (distilled water). The biotestes were monitored daily for a period of seven days, being moistened with distilled water if necessary. And during a period the seeds exposed to the treatments of germination and growth were monitored daily. The allelopathic action of the extracts on the germination speed index, root and stem length and percentage of germination of the seedlings were analyzed. It was concluded that there was a significant effect of the extracts of P. aduncum in a positive way in relation to the growth stimuli caused by the seeds surviving the highest concentrations (5% and 7.5%), or negatively affecting the growth index Speed of germination with the increase of extracts concentrations, besides causing mortality of some seeds.