Effects of nitrogen forms on growth and nitrogen assimilation and utilization of Buchloe dactyloides北大核心CSCD

This research explored the nitrogen (N) uptake preference of Buchloe dactyloides, in order to improve the management of this species over the whole growth cycle. The experiment included two cultivars of B. dactyloides (‘Sundancer’ and ‘Texoka’) and four different N regimes (N0: No N as the control, N1: Urea, N2: Nitrate N, N3: Ammonium N and N4: a 1:1 mixture of nitrate N and ammonium N). The rate of N applied was 500 mg N·kg soil–1 in each case. It was found that total N content, root nitrate reductase (NR) activity, glutamine synthetase (GS) activity and shoot glutamate synthase (GOGAT) activity of B. dactyloides were significantly improved by adding mixed N (P<0.05). Shoot nitrate N content of B. dactyloides was significantly improved by adding nitrate N (P<0.05). Root nitrate N and ammonium N contents of B. dactyloides were significantly improved by adding urea (P<0.05). The shoot ammonium N content and NR activity of B. dactyloides were significantly improved by adding ammonium N (P<0.05). Shoot GS activity of B. dactyloides was significantly reduced by adding ammonium N (P<0.05). Root GOGAT activity of B. dactyloides was significantly reduced by adding nitrate N (P<0.05). Mixed N can better improve the physiological activity and promote the growth of B. dactyloides, but single nitrogen source will inhibit some nitrogen assimilase activity. Based on these results, it is recommended that 1:1 mixed nitrogen should be used as the nitrogen source in the production of B. dactyloides. Where the ammonium:nitrate is not 1:1, urea should be used as the nitrogen source. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.

Effects of nitrogen forms on growth and nitrogen assimilation and utilization of Buchloe dactyloides

This research explored the nitrogen （N） uptake preference of Buchloe dactyloides, in order to improve the management of this species over the whole growth cycle. The experiment included two cultivars of B. dactyloides （‘Sundancer’ and ‘Texoka’） and four different N regimes （N₀： No N as the control, N₁： Urea, N₂： Nitrate N, N₃： Ammonium N and N₄： a 1∶1 mixture of nitrate N and ammonium N）. The rate of N applied was 500 mg N·kg soil^–1 in each case. It was found that total N content, root nitrate reductase （NR） activity, glutamine synthetase （GS） activity and shoot glutamate synthase （GOGAT） activity of B. dactyloides were significantly improved by adding mixed N （P<0.05）. Shoot nitrate N content of B. dactyloides was significantly improved by adding nitrate N （P<0.05）. Root nitrate N and ammonium N contents of B. dactyloides were significantly improved by adding urea （P<0.05）. The shoot ammonium N content and NR activity of B. dactyloides were significantly improved by adding ammonium N （P<0.05）. Shoot GS activity of B. dactyloides was significantly reduced by adding ammonium N （P<0.05）. Root GOGAT activity of B. dactyloides was significantly reduced by adding nitrate N （P<0.05）. Mixed N can better improve the physiological activity and promote the growth of B. dactyloides, but single nitrogen source will inhibit some nitrogen assimilase activity. Based on these results, it is recommended that 1∶1 mixed nitrogen should be used as the nitrogen source in the production of B. dactyloides. Where the ammonium∶nitrate is not 1∶1, urea should be used as the nitrogen source.