中国农业科学 ›› 2018, Vol. 51 ›› Issue (16): 3074-3083.doi: 10.3864/j.issn.0578-1752.2018.16.004

• 耕作栽培·生理生化·农业信息技术 • 上一篇    下一篇

不同基因型高粱的氮效率及对低氮胁迫的生理响应

刘鹏1,2,3,武爱莲2,王劲松2,南江宽2,董二伟2,焦晓燕2,平俊爱3,白文斌3

 
  

  1. 1山西大学生物工程学院,太原 030006;2山西省农业科学院农业环境与资源研究所,太原 0300313山西省农业科学院高粱研究所,山西晋中 030600
  • 修回日期:2018-02-08 出版日期:2018-08-16 发布日期:2018-08-16
  • 通讯作者: 焦晓燕,E-mail:xiaoyan_jiao@126.com
  • 作者简介:刘鹏,E-mail:434466047@qq.com
  • 基金资助:
    国家现代农业产业技术体系(CARS-06-13.5-A20)、山西省农业科学院优势课题组项目(YYS1707)、高粱遗传与种质创新山西省重点实验室项目(2016K-03)

Nitrogen Use Efficiency and Physiological Responses of Different Sorghum Genotypes Influenced by Nitrogen Deficiency

LIU Peng1,3, WU AiLian2, WANG JinSong2, NAN JiangKuan2, DONG ErWei2, JIAO XiaoYan2PING JunAi3, BAI WenBin3   

  1. 1College of Biological Engineering, Shanxi University, Taiyuan 030006; 2Institute of Agricultural Environment and Resources, Shanxi Academy of Agricultural Sciences, Taiyuan 030031; 3Institute of Sorghum, Shanxi Academy of Agricultural Sciences, Jinzhong 030600, Shanxi
  • Revised:2018-02-08 Online:2018-08-16 Published:2018-08-16

摘要: 【目的】探讨不同基因型高粱氮素吸收效率和利用效率及其差异机制,研究低氮胁迫对不同基因型高粱叶片无机氮含量和氮同化酶活性的影响,为耐低氮型高粱品种的选育提供理论依据。【方法】采用盆栽试验,选取2个低氮敏感型高粱(冀蚜2号和TX7000B)和2个耐低氮型高粱(SX44B和TX378)为试验材料,设置高氮(0.24 g·kg-1风干土)和低氮(0.04 g·kg-1风干土)2个处理,分别在挑旗期和灌浆期测定高粱叶片NO3- -N、NO2--N及NH4+ -N含量和硝酸还原酶(NR)、亚硝酸还原酶(NiR)、谷氨酰胺合成酶(GS)和谷氨酸合成酶(GOGAT)活性,分析不同基因型高粱在2个氮处理下的氮效率相关指标及其差异。【结果】(1)不同基因型高粱籽粒产量对低氮的响应不同,低氮处理显著降低了冀蚜2号和TX7000B的籽粒产量,与高氮处理比较分别降低13.87% 和19.25%,但没有降低SX44B和TX378的籽粒产量。(2)与高氮处理比较,低氮处理的相对籽粒氮累积量、相对植株氮累积量和相对氮收获指数不能表征各基因型高粱是否具有耐低氮特性;但相对低氮敏感型高粱,耐低氮型高粱在低氮处理下有着较高的相对氮肥偏生产力和相对氮素利用效率。低氮处理下SX44B和TX378的氮肥偏生产力是高氮处理的6.19和7.49倍,而冀蚜2号和TX7000B则分别为5.17和4.85倍;低氮处理下SX44B和TX378的氮素利用效率是高氮处理的1.84和1.85倍,而冀蚜2号和TX7000B则分别为1.67和1.35倍。(3)通径分析表明,高氮处理下,植株氮累积量和氮素利用效率对籽粒产量贡献相同;而在低氮处理下,氮素利用效率对籽粒产量关联作用更大。(4)高粱的叶片无机氮含量不能表征高粱是否具有耐低氮特性,灌浆期叶片无机氮含量较挑旗期显著降低。(5)与高氮处理比较,低氮处理时冀蚜2号和TX7000B叶片中NR、GS和GOGAT活性显著降低,SX44B酶活性变化不显著,而TX378叶片中GS活性增加。【结论】耐低氮型高粱在低氮胁迫时有着较高的相对籽粒产量和相对氮素利用效率。低氮胁迫时叶片较高的氮同化酶活性是高粱耐低氮的生理基础。发掘和利用低氮条件下具有较高的叶片氮同化酶活性和氮素利用效率的高粱种质资源,有助于提高耐低氮高粱品种的培育效率。

关键词: 高粱, 氮素吸收效率, 氮素利用效率, 氮同化关键酶

Abstract: 【Objective】 The aim of this study was to investigate the genotypic variability for sorghum nitrogen (N) use efficiency and related traits, and the effects of low nitrogen stress on leaf inorganic nitrogen content and nitrogen assimilation enzymes of sorghum, so as to provide theoretical basis for further improvement in the cultivation of low-N tolerant sorghum genotypes. 【Method】 The experiment was conducted in greenhouse by means of pot with soil medium. There were two N levels (HN: 0.24 g N·kg-1 soil, LN: 0.04 g N·kg-1 soil). Four sorghum genotypes, two of which were low-N susceptible genotypes (Jiya2 and TX7000B) and the other two were low-N tolerant genotypes (SX44B and TX378), were employed to explore the effects of low nitrogen stress on plant growth, yield, N use efficiency, leaf inorganic nitrogen (NO3- -N, NO2--N and NH4+-N) content, and nitrogen assimilation enzymes in terms of nitrate reductase (NR), glutamine synthetase (GS) and glutamate synthetase (GOGAT) at both flag leaf and grain filling stages. 【Result】 (1) Compared with the grain yield (GY) of HN treatment, LN treatment resulted in a decrease of 13.87% and 19.25% for Jiya2 and TX7000B, respectively, However, LN treatment didn’t decrease the GY of SX44B and TX378. (2) The relative grain N accumulation, relative plant N accumulation and relative N harvest index (ratios of trait values under LN treatment to those under HN treatment) were inconsistent with the low nitrogen tolerant performance of sorghum. By contrast, the low-N tolerant genotypes had a higher relative nitrogen partial factor productivity (NPFP) and relative nitrogen utilization efficiency (NutE) than low-N susceptible genotypes. The NPFP of SX44B and TX378 under LN treatment were 6.19 and 7.49 times than that under HN treatment, respectively, while the NPFP of Jiya2 and TX7000B were 5.17 and 4.85 times, respectively. The NutE of SX44B and TX378 under LN treatment were 1.84 and 1.85 times of that under HN treatment, whereas the values of Jiya 2 and TX7000B were 1.67 and 1.35 times, respectively. (3) Path analysis showed that plant nitrogen accumulation and NutE contributed the same to grain yield under HN treatment, while the importance of NutE was over plant nitrogen accumulation in defining the GY under LN treatment. (4) Leaf inorganic N content was irrelevant to the low N tolerance of sorghum. Leaf inorganic N content at flag leaf stage was significantly lower than that at grain filling stage. (5) LN treatment significantly decreased the leaf NR, GS and GOGAT activity of Jiya2 and TX7000B. On the contrary, leaf nitrogen assimilation enzyme activity of SX44B was not notably changed by N level, and leaf GS activity of TX378 was significantly increased under LN treatment.【Conclusion】Low-N tolerant sorghum genotypes had a higher relative GY and relative NutE under LN treatment. Maintaining relatively high nitrogen assimilation enzyme activity was the physiological basis of low-N tolerant sorghum genotypes. Exploring and utilizing sorghum germplasm resources with high nitrogen assimilation enzyme activity and high NutE under low nitrogen conditions should be helpful to improve the breeding efficiency of low-N tolerant sorghum genotypes.

Key words: Sorghum bicolor (L.) Moench, nitrogen uptake efficiency, nitrogen utilization efficiency, nitrogen assimilation enzymes