Allelopathic potential of extracts the from marine macroalga Plocamium brasiliense and their effects on pasture weed

Four extracts from the marine red alga Plocamium brasiliense (Greville) M.A.Howe & W.R.Taylor were prepared to identify and characterize their potential allelopathic effects on seed germination, radicle elongation and hypocotyl development of the weeds Mimosa pudica L. and Senna obtusifolia (L.) Irwin & Barneby. The four extracts were prepared in a sequence of solvents of increasing polarity: n-hexane, dichloromethane, ethyl acetate and ethanol/water (7:3). The germination bioassay was carried out at 25 °C with a 12 h photoperiod and the radicle elongation and hypocotyl development at 25 °C ...