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草业学报 ›› 2017, Vol. 26 ›› Issue (10): 207-218.DOI: 10.11686/cyxb2016501

• 研究论文 • 上一篇    下一篇

不同氮素水平对饲用苎麻氮代谢关键酶的影响

陈继康*, 谭龙涛*, 喻春明, 朱爱国, 陈平, 王延周, 朱涛涛, 熊和平*   

  1. 中国农业科学院麻类研究所,湖南 长沙 410205
  • 收稿日期:2016-12-28 出版日期:2017-10-20 发布日期:2017-10-20
  • 通讯作者: ramiexhp@vip.163.com
  • 作者简介:陈继康(1985-),男,宁夏海原人,助理研究员。E-mail:chenjikang@caas.cn。谭龙涛(1984-),男,黑龙江佳木斯人,在读博士。E-mail:3828134@163.com。
  • 基金资助:
    湖南省科技计划重点研发计划项目(2016NK2205),国家麻类产业技术体系建设专项(CARS-19)和中国农业科学院科技创新工程多年生麻类作物遗传改良团队资金(ASTIP-IBFC04)资助

Effects of different nitrogen levels on key enzyme activities associated with nitrogen metabolism of feed ramie

CHEN Ji-Kang**, TAN Long-Tao**, YU Chun-Ming, ZHU Ai-Guo, CHEN Ping, WANG Yan-Zhou, ZHU Tao-Tao, XIONG He-Ping*   

  1. Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China
  • Received:2016-12-28 Online:2017-10-20 Published:2017-10-20

摘要: 苎麻是适于中国南方种植的优质植物蛋白质饲料作物,但缺乏氮素利用的生理基础研究。为了明确氮素水平对饲用苎麻氮代谢相关酶的影响,本研究以氮高效基因型苎麻H2000-03和氮低效基因型苎麻册亨家麻为材料进行了盆栽试验,设置0、6、9、12、15 mmol/L氮素处理水平,分析了苎麻幼苗期(15 d)、旺长期(40 d)和成熟期(54 d)氮代谢及抗性关键酶活性的动态变化特征及相关关系,并采用模糊隶属函数法进行了综合评价。结果表明:(1)随着氮素处理浓度的增加,两个苎麻品种的株高、鲜重及叶片蛋白质含量呈先增加后下降或趋于平稳的趋势,表明苎麻对氮素需求存在最适量,低于或高于最适水平将导致显著的产量降低或报酬递减现象。H2000-03在不同氮素水平下的株高和鲜产均显著高于册亨家麻,在适宜氮素水平下(9~12 mmol/L)叶片蛋白质含量也显著较高,并在高氮胁迫下可维持鲜产,整体表现出较高的生产力和稳产性。(2)在不同生长时期,两个苎麻品种NR活性随氮素浓度的提高逐渐升高,而GS、GOGAT、GLDH、CAT、SOD和POD等酶活呈单峰变化趋势。H2000-03的NR、GS、GOGAT、CAT活性及高氮水平下的SOD、POD活性均高于册亨家麻,而GLDH和低氮水平下的SOD和POD活性较低,整体表现出较高的生理响应和适应能力。(3)苎麻氮代谢与抗性关键酶与其产量和品质变化特征一致,可用于监测、表征苎麻基因型间氮素利用的差异。本研究认为:相对于持续提高氮素用量,苎麻可在适宜的氮素水平下达到生理特性与生产性能的契合,旺长期氮代谢相关酶活性可作为饲用苎麻品种选育的指标之一。

Abstract: Ramie (Boehmeria nivea) is an important source of plant protein in South China. Few studies investigating the physiological mechanisms of nitrogen utilization in feed ramie have been reported. To evaluate the activities of key enzymes associated with nitrogen metabolism in ramie, a potted experiment was conducted under different nitrogen levels. Two ramie varieties, H2000-03 which has high nitrogen utilization efficiency (NUE, 46.01%) and Ceheng Jiama with low NUE (15.81%) were treated with 0, 6, 9, 12 and 15 mmol/L nitrogen, and enzyme activity tested at the seedling stage (15 days), maximum growth (40 days) and at maturity (54 days). The results showed that as nitrogen concentration increased plant height, fresh yield and leaf protein content of both varieties increased and subsequently decreased or plateaued, indicating that the range of treatments imposed was able to meet the nitrogen requirement of the ramie plants. Plant height and fresh yield of H2000-03 were significantly higher than that of Ceheng Jiama under all treatments. The leaf protein content of H2000-03 was distinctly higher than that of Ceheng Jiama under a range of nitrogen levels (9-12 mmol/L). These results suggest that H2000-03 has better productivity under a range of nitrogen availabilities and more stable production under nitrogen deficient conditions. At different growth periods, the activity of NR (nitrate reductase) in H2000-03 and Ceheng Jiama gradually increased with increased nitrogen supply, while the activities of glutamine synthetase (GS), glutamate synthase (GOGAT), glutamic dehydrogenase (GLDH), catalase (CAT), superoxide dismutase (SOD) and peroxidase (POD) first increased and then decreased. The activities of POD, GS, GOGAT, CAT in H2000-03 under all nitrogen levels and the activities of SOD and POD under high nitrogen levels were higher than in Ceheng Jiama, while lower GLDH at all nitrogen levels and lower SOD and POD at low nitrogen levels were detected in H2000-03 compared to Ceheng Jiama. These results indicate that H2000-03 had a better physiological response and adaptability to different nitrogen fertility levels. The dynamic characteristics of ramie yield and quality were consistent with enzyme activity related to nitrogen metabolism and resistance which could be used to monitor and characterize nitrogen utilization differences among genotypes. Our research suggests that an appropriate nitrogen fertility range, rather than continuously increasing nitrogen should be ascertained to coordinate productivity with physiological characteristics. The activity of key enzymes during the rapid growth phase is suggested as an important trait for feed ramie breeding.