The effect of 0.5, 1.0 and 2.0 mM nano calcium hydroxide Ca(OH)2 and calcium oxide CaO or
bulk calcium carbonate CaCO3 on growth and metabolic changes of Lupines termis seedlings was assessed.
Root fresh and dry weights were increased by nano CaO at 0.5 and 1.0 mM compared with the control, while
they were decreased by increasing nano Ca(OH)2. Shoot fresh and dry weights were increased by increasing
the concentration of nano Ca(OH)2 and CaO reaching their maximum at 0.5 and 2.0 mM, respectively. Bulk
CaCO3 concentrations increased root and shoot fresh and dry weights at the highest concentration (2mM).
The photosynthetic pigments (chl.a, chl.b and carotenoids) were markedly increased with increasing the
concentration of nano Ca (OH)2, nano CaO and bulk CaCO3 with the highest magnitude recorded for nano
Ca(OH)2, while the lowest was for CaCO3. The total soluble carbohydrate biosynthesis of both shoot and
root was reduced by nano calcium particles, whereas it was enhanced by bulk calcium compared with
control. The root soluble protein was decreased by different concentrations of either nano or bulk calcium,
while shoot soluble protein was increased by all calcium treatments compared with the control. The nano
calcium especially Ca(OH)2 activated the protein metabolism compared with the bulk. The root and shoot
phenolic compounds were decreased by different concentrations of either nano or bulk calcium, except of the
shoot phenolic compounds at CaCO3. Nano CaO at 0.5 mM increased shoot phenolic compounds by 10%
compared with control.