Germination and sporophytic development of Regnellidium diphyllum Lindm. (Marsileaceae) in the presence of copper

Regnellidium diphyllum Lindm. is a heterosporous fern growing in wetlands and humid soils that are being converted to agricultural activities. Many products that are used in agriculture contain copper, resulting in surface and groundwater contamination. Germination and initial development tests were performed using Meyer's solution containing copper sulphate at concentrations of 0 (control), 1, 5, 10, 50 and 100 mg L-1. The experiment was conducted in a growth chamber at 25 ± 1ºC for 28 days, with a 12/12-hour light/dark cycle and a photon flux density of 100 µmol m-2 s-1. The lowest germin...