摘要
本研究以Na Cl为盐分模拟不同盐度环境(轻度S1:2.5 g·kg^(-1);中度S2:5.0 g·kg^(-1);重度S3:7.5g·kg^(-1)),研究了施氮对盐环境下甜菜生长发育与氮素吸收利用状况的影响。结果表明:(1)在实验的三种盐度条件下,在N1(0.3 g·kg^(-1))~N4(2.4 g·kg^(-1))的范围内施氮可显著缓解盐胁迫对甜菜造成的伤害或显著增强其在盐胁迫下的生存能力,甜菜在轻度与中度盐胁迫下的最佳施氮量均为N3(1.2 g·kg^(-1)),在重度盐胁迫下的最佳施氮量为N2(0.6 g·kg^(-1));(2)在轻、中、重三种盐度下,随着施氮水平(0~2.4 g·kg^(-1))的提高,甜菜叶片渗透势随之降低,渗透调节能力呈增强趋势;(3)在各盐度环境下,施氮均可促进甜菜叶片(同化枝)光合色素的合成,增加光合色素含量,从而提高光合效率,同时增强其对盐渍环境的适应能力;(4)在三种盐度下,随着施氮量的增加甜菜氮素生产力与氮肥农学利用效率均呈现出下降的趋势,在N1(0.3 g·kg^(-1))~N3(1.2 g·kg^(-1))水平下表现为大幅度下降,并且氮素生产力与氮肥农学利用效率均随着盐度的增加而下降;(5)在三个盐度环境下,甜菜块根、叶柄、叶的含氮量均随着施氮量(0~2.4 g·kg^(-1))的增加而升高,且同一施氮水平下甜菜各部位含氮量总体表现为:叶>叶柄>块根;(6)在轻、中、重三种盐度胁迫下的最高施氮限量分别为1.39、1.33 g·kg^(-1)和1.24 g·kg^(-1)(其最高干物质产量分别为90.09、72.86 g·pot^(-1)和32.47 g·pot^(-1))。
In a pot experiment, sodium chloride was used to imitate three salinity level： mild（S j） , medium （S2^ and serious （S3） to investigate the effect of nitrogen fertilization on the growth and development, nitrogen uptake and uti-lization in sugar beet in salt environment. The main results were shown as follows： （1） Nitrogen application （0.3 ？2.4 g ＇kg-1） can significantly alleviate the damage caused by salt stress to sugar beet and enhance its ability to survive under salt stress. In mild（S!） and medium（S2） salt concentration, the optimum nitrogen application of sugar beet was 1 - 2 g ＊ kg-1. In high （S3） salt concentration, the optimum nitrogen application was 0.6 g ·k g-1. （2） The osmotic potential of sugar beet leaves decreased with nitrogen application increasing （0 ？2.4 g ·k g-1） in three concentration of NaCl and os-motic adjustment ability showed an trend of increase. （3） Nitrogen application could promote the synthesis of photosyn-thetic pigments in beet assimilation branches under different salinity, resulting in a high photosynthetic efficiency. （4） Both nitrogen productivity and agronomic nitrogen use efficiency showed a descending trend with nitrogen application in-creasing in three concentration of NaCl. They dropped dramatically when nitrogen application was 0.3 -1.2 g· k g-1. Both nitrogen productivity and nitrogen agronomic efficiency ranked as Si -S2 -S3 in the same nitrogen level . （5） Nitro-gen content in tuber, petiole and leaf of sugar beet increased with nitrogen application increasing（0-2.4g·kg-1） in three concentration of NaCl. Nitrogen content generally appeared as leaf 〉 petiole 〉 tuber in the same nitrogen level. （6） The upper limit of nitrogen application was 1.39, 1.33 g ·k g-1 and 1.24 g·k g-1 in the S j, S2 and S3 salinity, and for each of them, the highest yield of sugar beet of 90.09, 72.86 g ·pot-1 and 32.47 g ·pot-1 respectively, was harvested.
出处
《干旱地区农业研究》
CSCD
北大核心
2017年第3期204-211,共8页
Agricultural Research in the Arid Areas
基金
国家星火计划项目(2015GA184003)
关键词
甜菜
盐胁迫
施氮量
氮素利用率
生长发育
渗透势
sugar beet
salt stress
nitrogen fertilizer application level
nitrogen use efficiency
growth and development
osmotic potential
