Role of Nitrogen Fertilizer on Cadmium Uptake by Ramie (Boehmeria nivea (L.) Gaudich) Grown on Cadmium Contaminated Soil

Abstrak

ABSTRACT
Continues phosphate fertilization as well as organic matter amendment can increase cadmium concentration
in soil and induce more cadmium uptake by plants. Pytoremediation using non edible plant such as ramie
(Boehmeria nivea L. Goud) is cheap and effective method to extract Cd from Cd-contaminated soil. Since in
plant tissue Cd is bound in phytochelatin peptide which contains nitrogen and sulphur, the objective of this
green house experiment was to assess the influence of nitrogen fertilizer in form of urea on cadmium
uptake, nitrogen and sulphur concentration in shoots as well as shoot dry weight of 60-day old ramie
grown in cadmium-contaminated soil. The experiment was set up in a Split Plot Design with two treatments
and three replications. The main plot was cadmium levels (0, 10 and 15 mg kg-1) and subplot was urea level
(0, 5.0 and 7.5 g pot-1). The result showed that the increase of cadmium concentration in soil enhanced its
concentration in ramie shoot regardless of urea levels. However either cadmium or urea did not change
sulphur concentration in ramie shoot. Urea of 7,5 g/pot increased shoot dry weight but adding CdCl2.H2O of
15 mg/kg did not change shoot dry weight. This experiment demonstrated that ramie was able to grow in
relatively high level of soil cadmium, and higher cadmium uptake by ramie shoot was not followed by an
increase in nitrogen as well as sulphur uptake.
Keywords: Cadmium, Urea, Nitrogen, Sulphur, Ramie.