Arid Zone Research ›› 2021, Vol. 38 ›› Issue (2): 460-468.doi: 10.13866/j.azr.2021.02.17

• Plant and Plant Physiology • Previous Articles     Next Articles

Effects of nitrogen addition and precipitation on Reaumuria soongorica physiological indices

YANG Jie(),SHAN Lishan(),BAI Yamei,ZHANG Wanting,ZHANG Zhengzhong,XIE Tingting,LI Yi   

  1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China
  • Received:2020-09-16 Revised:2020-10-14 Online:2021-03-15 Published:2021-04-25
  • Contact: Lishan SHAN E-mail:yj1230163@163.com;shanls@gsau.edu.cn

Abstract:

Water and nitrogen are the key factors limiting the growth and development of desert plants. To predict the impact of climate change on desert vegetation growth in the future, understanding the effects of nitrogen and water on plant physiology is essential. We investigated the effects of nitrogen application and precipitation on Reaumuria soongorica seedlings. Proline (Pro), chlorophyll (Chl), superoxide dismutase (SOD), peroxidase (POD), and soluble protein (SP) contents in R. soongorica leaves were measured under different precipitation treatments [precipitation decreases 30% (W-), natural precipitation (W), and precipitation increases 30% (W+)] and nitrogen applications [N0(0 g·m -2·a-1), N1 (4.6 g·m-2·a-1), N2 (9.2 g·m-2·a-1), N3 (13.8 g·m-2·a-1)]. Under natural precipitation (W) and precipitation increases 30% (W+), proline and chlorophyll contents increased with increased nitrogen application. The coupling effect of water and nitrogen promoted the accumulation of proline and chlorophyll when the water condition was suitable. In the no nitrogen (N0) and low nitrogen (N1) treatments, POD activity under natural precipitation (W) was significantly lower than that under precipitation decreases 30% (W-), while the opposite trend was observed in the medium nitrogen (N2) and high nitrogen (N3) treatments. The results showed that at low nitrogen levels, increased precipitation inhibited POD activity, while the addition of nitrogen mitigated the inhibition and promoted POD activity, demonstrating the compensation effects of nitrogen and water. Under natural precipitation (W) conditions, the soluble protein content first increased and then decreased as the nitrogen concentration increased, while the effect of nitrogen addition on soluble protein content was not significant under precipitation decreases 30% (W-). These findings demonstrate that under normal water conditions, appropriate nitrogen addition could promote the transformation of plant protein up to a certain concentration threshold, then continuous nitrogen increases inhibit soluble protein production. Conversely, nitrogen application had no significant effect on soluble protein transformation under water deficits.

Key words: precipitation change, nitrogen addition, physiological index, Reaumuria soongorica