Effects of Nitrogen Concentration on Root Respiration Rate and Nonstructural Carbohydrates of Walnut Seedlings
Effects of Nitrogen Concentration on Root Respiration Rate and Nonstructural Carbohydrates of Walnut Seedlings
复制标题
DOI：
10.7235/hort.20200031
复制
发表时间：
2020-06
影响因子：
--
通讯作者：
Chun-Ping Li;Shiwei Wang;Cuifang Zhang;J. Ding;Bin Ma;Rabigul Yasin;Zezheng Xue
中科院分区：
文献类型：
--
作者：
Chun-Ping Li;Shiwei Wang;Cuifang Zhang;J. Ding;Bin Ma;Rabigul Yasin;Zezheng Xue
氮是森林生长和生产力的关键决定因素，而根系呼吸速率和非结构性碳水化合物是评价所提供养分效果的重要参数。在此，我们研究了氮素对核桃幼苗的影响。在有利的条件下，这一数字持续增长了一年。采用0、1、2、4、8、12、16mmol.L-1等7种氮素有效氮浓度进行盆栽，用离体根系比色法和酮色比色法测定根系比呼吸速率和根系非结构性碳水化合物含量。氮素浓度与核桃幼苗的比根呼吸呈正相关，根径是影响核桃幼苗比根呼吸和非结构性碳水化合物含量的主要因素。在相同氮素浓度下，根的可溶性总糖和淀粉含量随着根径的增大而增加，而比根呼吸则随着根径的减小而增大。与0 mmol.L-1氮素浓度相比，氮素浓度为N16时，根系中非结构性碳水化合物的含量和比根呼吸强度都较高。综合分析表明，氮素浓度N16提高了核桃幼苗根系的呼吸速率，显著增加了幼苗根系中非结构性碳水化合物的含量，有效地促进了核桃幼苗根系的生长发育。新增关键词：相关性、调控机制、根径、可溶性总糖、淀粉
Nitrogen is a critical determinant of forest growth and productivity, and root respiration rate and nonstructural carbohydrates are important parameters for evaluating the effects of supplied nutrients. Here, we assessed the effects of nitrogen on walnut seedlings (Juglans regia Linn.) that grew consistently for a year under favorable conditions. Seedlings were potted in seven concentrations of N availability, 0, 1, 2, 4, 8, 12, and 16 mmol·L-1, and the specific root respiration rate and nonstructural carbohydrate content of the root system were determined via the off-body root system and the ketone color ratio methods, respectively. Nitrogen concentration was positively correlated with specific root respiration, and root diameter was the main factor related to specific root respiration and nonstructural carbohydrate content of walnut seedlings. Under the same nitrogen concentrations, the soluble total sugar and starch content of roots increased with increasing root diameter, while the specific root respiration increased with decreasing root diameter. Compared to the 0 mmol·L-1 nitrogen concentration, the content of nonstructural carbohydrates in the root system and the specific root respiration were higher when nitrogen concentration was N16. Our comprehensive analysis showed that a nitrogen concentration of N16 improved the respiration rate of the seedling root system, significantly increased the content of nonstructural carbohydrates in the seedling root system, and effectively promoted the growth and development of the seedling root system of walnut seedlings. Additional key words: correlation, regulatory mechanism, root diameter, soluble total sugar, starch