Allelopathic potential of Crysopogon zizanioides (L.) and Paspalum millegrana (Schrad) on the germination of lettuce

Abstract

The aim of this work was to evaluate the allelopathic effect of extracts of Chrysopogon zizanioides (L.) Roberty and Paspalum millegrana Schrad on germination of lettuce. Aqueous solutions were prepared by maceration and infusion at concentrations of 0, 1, 3 and 5%. In the extracts were measured the osmotic potential (OP), concentration of total soluble sugars (CTSS) and electrical conductivity (EC). The effects of the extracts on the germination of the seeds were evaluated by means of the following parameters: first germination count (FGC), germination (G), germination speed index (GSI) and mean germination time (MGT). Even at low concentrations it was possible to identify allelopathic effect, be it inhibiting or accelerating the growth of the seedlings. Low concentrations of the extract caused seed phytotoxicity at the beginning of the germination process. The aqueous extracts of the vetiver grass and paspalum grass showed allelopathic potential.