Abstract:To investigate the influences of root physiological growth characteristics on nitrogen(N) and phosphorus(P) uptake of Myriophyllum aquaticum under aerobic conditions, pot experiment was conducted. Root physiological growth characteristics, and N and P uptake characteristics of M. aquaticum were analysed. Five treatments were designed for 0, 4, 6, 8, and 10 min under aerobic conditions, the relationships between root characteristics and N and P uptake of M. aquaticum were determined. The results showed that, compared with the non-aerated CK group, N and P uptake amounts per plant of the stems and leaves under aerobic conditions were higher than those of the roots; the total N and P uptake amounts per plant of the roots, stems and leaves, and the whole plant, and the root vitality, root volume, root surface area and total root length of M. aquaticum at different growth stages under aerobic conditions could be increased. The N uptake amount, P uptake amount per plant, root activity, root volume, root surface area, and total root length of M. aquaticum in T5 period under aerobic conditions increased by 3.39%-72.06%, 14.40%-58.20%, 69.37%-275.14%, 18.57%-47.84%, 5.80%-64.88%, 2.70%-57.77%, respectively. The maximum values of N uptake amount per plant of T5 period(171.07 mg) in 6 minutes and P uptake amount per plant of T5 period(9.98 mg) in 8 minutes under aerobic conditions appeared, respectively. An aerobic treatment of 6-minute was a perfect aerobic time for regulating root physiological growth characteristics and promoting N and P uptake of M. aquaticum. In conclusion, aerobic regulation could significantly enhance the vitality and growth of the root system of M. aquaticum, and increase its uptake of N and P elements.