Nitrogênio, fósforo, potássio, cálcio e o crescimento de plântulas de Aechmea blanchetiana (Baker) L.B.Smith in Vitro. / Nitrogen, phosphorus, potassium, calcium and the in vitro growth of Aechmea blanchetiana (Baker) L.B. Smith plantlets.

AUTOR(ES)
DATA DE PUBLICAÇÃO

2005

RESUMO

Seedlings of the bromeliad Aechmea blanchetiana were axenically cultured in liquid MS basal medium without growth regulators but supplemented with different concentrations of nitrogen (7.5; 15; 30; 60 or 120 mM.L-1), phosphorus (0.15; 0.30; 0.60; 1.25 or 2.50 mM.L-1), potassium (2.5; 5; 10; 20 or 40 mM.L-1) or calcium (1.5; 3; 4.5; 6 or 12 mM.L-1). The resulting plantlets were cultured under 93 µmol.m-2.s-1 illumination, 12 hour photoperiod regime and 25oC ± 1 for 120 days with subcultures to fresh identical media every 30 days. The highest fresh weight for plantlets cultured in medium supplemented with nitrogen was 7.5 mM.L-1, whereas increased concentrations were shown to be excessive. For phosphorus (phosphate), 2.5 mM.L-1 produced the highest fresh and dry mass, while the optimal concentrations of potassium was found to be 32.6 mM.L-1 and higher concentrations were shown to be toxic. Calcium sustained the highest fresh and dry mass increase under 9.38 mM.L-1 but were excessive above that figure, especially due to the toxicity of chlorine from CaCl2.2H2O over the concentration of 3.35 mM.L-1.

ASSUNTO(S)

nitrogênio propagação vegetal bromélia fósforo nutrição vegetal plant nutrition potássio cálcio crescimento vegetal plant propagation calcium phsphorus bromeliad plant growth nitrogen

ACESSO AO ARTIGO

Documentos Relacionados