Effects of N and Ca Fertilizers on Root Morphology, Physiological Metabolism and Yield of Nicotiana tabacum

Abstract:

In order to understand the influence of N and Ca fertilizers on growth of Nicotiana tobacum, the changes in root morphology and physiological indexes and yield were studied at mature stage. The results showed that length of the longest lateral root, root volume, dry weights of root and leaf, and soluble protein content in root of N. tobacum all increase significantly treated with 0.20 g kg^-1 N than those with 0.12 g kg^-1 N, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity decreased significantly, the numbers of lateral root, catalase (CAT) activity and superoxide anion radical (O₂^·) all had not significant differences. The root volume, number of lateral root, activities of CAT and SOD, and soluble protein content in root treated with 0.40 g kg^-1 Ca were all higher than those under control, while both of MDA content and O₂^· decreased. If treated with 1.00 g kg^-1 Ca, length of the longest lateral root, dry weights of root and leaf increased. The effect of N×Ca interaction on length of the longest lateral root, root volume, dry weights of root and leaf, and physiological metabolism indexes of N. tobacum were all significant, but that on number of lateral root was not significant. Therefore, the root morphology, physiological metabolism and yield of N. tobacum could be furthest improved supplement with 0.20 g kg^-1 N and 0.40 g kg^-1 Ca.