Comparative studies of Al3+ ions and Al2O3 nanoparticles on growth and metabolism of cabbage seedlings

In the present study, we compared the effects of Al3+ ions and alumina (Al2O3) nanoparticles (NPs) on growth and biochemical parameters of cabbage seedlings. The seedlings were treated with A = 698.8 μM Al3+ions and A1 = 101.8 μM, A2 = 253.8 μM, A3 = 507.7 μM, A4 = 1.02 mM, A5 = 2.17 mM NPs of Al2O3 in 700 mL Hoagland solution. The untreated seedlings were taken as control. It was observed that aluminium ions were phytotoxic and adversely affected seedling growth and biochemical parameters of the test crop with stunting of the stem growth, while lower doses of alumina NPs enhanced seedling growth, pigments, sugar and protein contents of cabbage (Brassica oleracea var. capitata) seedlings. Higher doses of alumina NPs adversely affected biochemical parameters and nitrate reductase activities of the treated seedlings. Alumina NPs induced activities of antioxidant enzymes viz. SOD, CAT and POX. Antioxidant enzyme activities increased under all treatments with maximum increase in the seedlings treated with aluminium ions and higher concentrations of alumina NPs. The lower amount of alumina NPs buttressed the metabolic processes of the test crop and appeared to mitigate the phytotoxic effects of aluminium ions.