施氮肥和钙肥对烤烟根系形态、生理代谢及产量的影响

摘要

In order to understand the inlfuence 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 signiifcantly 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 (O2–4) all had not signiifcant 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 O2–4 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 signiifcant, but that on number of lateral root was not signiifcant. 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.%为了解氮肥和钙肥对烤烟(Nicotiana tabacum)生长的影响，对成熟期烤烟的根系形态、生理代谢指标和产量进行了研究。结果表明，与施0.12 g kg–1氮相比，施0.20 g kg–1氮的烤烟根系最长侧根长、根系体积、根干重、叶干重和可溶性蛋白质含量均极显著升高，MDA含量极显著下降，SOD活性显著下降，但对侧根数、CAT活性和O2–4的影响均不显著。施钙0.40 g kg–1，根系体积、侧根数、CAT和SOD活性以及可溶性蛋白质含量均比对照提高，MDA含量和O2–4则降低；施钙1.00 g kg–1，最长侧根长、根干重和叶干重均提高。氮×钙互作对烤烟的最长侧根长、根系体积、根干重、叶干重和生理代谢指标的影响均极显著，但对侧根数的影响不显著。因此，施0.20 g kg–1氮和0.40 g kg–1钙能最大限度地改善烤烟根系形态、生理状况及提高产量。