中国农业科学 ›› 2021, Vol. 54 ›› Issue (7): 1455-1468.doi: 10.3864/j.issn.0578-1752.2021.07.011

• 肥水高效利用 • 上一篇    下一篇

不同氮吸收效率水稻品种的苗期铵吸收特性及生长差异分析

黄秀,叶昌,燕金香,李福明,褚光,徐春梅,陈松,章秀福,王丹英()   

  1. 中国水稻研究所/水稻生物学国家重点实验室,杭州 311400
  • 收稿日期:2020-03-23 接受日期:2020-05-29 出版日期:2021-04-01 发布日期:2021-04-22
  • 通讯作者: 王丹英
  • 作者简介:黄秀,E-mail: huangjinxiu922@163.com
  • 基金资助:
    国家自然科学基金面上项目(31671630);国家重点研发计划(2016YFD0300108)

Analysis of Ammonium Uptake and Growth Differences of Rice Varieties with Different Nitrogen Recovery Efficiency at Seedling Stage

HUANG Xiu,YE Chang,YAN JinXiang,LI FuMing,CHU Guang,XU ChunMei,CHEN Song,ZHANG XiuFu,WANG DanYing()   

  1. China National Rice Research Institute/State Key Laboratory of Rice Biology, Hangzhou 311400
  • Received:2020-03-23 Accepted:2020-05-29 Online:2021-04-01 Published:2021-04-22
  • Contact: DanYing WANG

摘要: 【目的】 测定不同氮吸收效率品种对外界NH4 +浓度的响应,解释水稻品种间氮吸收差异的机理。【方法】 采用水培法栽培氮吸收高效的水稻品种齐粒丝苗(QL)和氮吸收低效的品种沪科3号(HK),通过分析水稻幼苗在0—0.80 mmol·L -1低铵浓度和1.00—12.96 mmol·L -1高铵浓度下的铵吸收速率,计算铵吸收动力学参数Vmax和Km值,比较不同氮吸收效率水稻品种的苗期铵吸收特性;通过比较不同NH4 +浓度下的水稻苗期株高、分蘖数、叶绿素含量、以及地上和地下部的干物质和氮素积累量,用根系扫描法分析根系形态,包括总根长、根体积、根表面积、平均直径、根尖数等,用非损伤性扫描离子选择电极技术(scanning ion-selective electrode technique,SIET)测量根分生区和伸长区NH4 +的跨细胞膜运输,用液相氧电极系统分析根系氧损耗,研究不同氮吸收效率水稻品种的苗期生长差异。【结果】(1)在0—0.8 mmol·L -1低铵浓度下,2个水稻品种QL和HK幼苗对NH4 +的吸收符合Michaelich-Menten方程,氮吸收高效品种QL的吸收动力学参数Vmax为氮吸收低效品种HK的1.66倍;当NH4 +的浓度大于1 mmol·L -1 时,水稻幼苗对NH4 +的吸收均随着外界NH4 +浓度的增加而增大,但同一NH4 +浓度下,氮吸收高效品种QL对NH4 +的吸收速率大于氮吸收低效品种HK;(2)水稻根系分生区在外界不同NH4 +浓度下均表现为NH4 +的跨细胞膜净流入,且NH4 +净流入速率随着外界NH4 +浓度的升高而增加,氮吸收高效品种QL在低铵(LN)、中铵(MN)和高铵(HN)处理下根系分生区NH4 +净流入速率分别比氮吸收低效品种HK高42.0%、71.8%和63.6%;根系伸长区NH4 +的跨细胞膜流通品种间存在差异,氮吸收低效品种HK在LN和HN下均出现NH4 +跨细胞膜净输出,而氮吸收高效的品种QL仅在HN下出现NH4 +跨细胞膜净输出,且净输出速率比氮吸收低效的HK低34.30%。(3)在LN和MN浓度下,氮吸收高效品种QL的苗期形态和物质积累并不占优势;适量增铵可以增加水稻的株高、分蘖、叶绿素含量、干物质和氮素积累量,但过高的外界铵浓度对水稻生长特别是根系生长有抑制作用;HN下,氮吸收高效的品种QL显示出一定的生长优势,播种后10–20 d的分蘖增加速率和干物质增加速率分别比氮吸收低效的品种HK高65.7%和31.4%;虽然品种QL的根系氮浓度比品种HK低15.1%,但其地上部氮积累量比HK高23.5%,说明QL比HK能更快地将根系吸收的氮转运至地上部供其生长所需。【结论】 与氮吸收低效品种相比,氮吸收高效品种根系细胞膜上有更多的NH4 +运输载体,根系吸收的NH4 +同化、转运速度快,苗期分蘖速率和干物重积累速率大。

关键词: 水稻, 氮吸收效率, 铵吸收, NH4 +流通, 苗期形态

Abstract:

【Objective】The aim of this study was to determine the response of different N recovery efficiency (NRE) varieties to external NH4 +concentration, and to explain the mechanism of N uptake difference among rice varieties.【Method】A high-NRE (QL) and a low-NRE (HK) rice variety were cultivated hydroponically at different NH4 +concentrations, and the varietal difference of NH4 + absorption at seedling stage were compared by analysis of the root NH4 + absorption rate at the low NH4 + concentration of 0-0.80 mmol·L -1 and the high NH4 + concentration of 1.00-12.96 mmol·L -1, and by calculating the NH4 + absorption kinetics parameter Vmax and Km; The difference of seedling growth between varieties were analyzed by comparing the plant height, tiller number, chlorophyll content, dry matter and N accumulation of aboveground and underground part of rice seedlings growing in different NH4 +concentrations, root morphology including total root length, root volume, root surface area, average root diameter, and root tip number were analyzed using the root scanning instrument; The root net fluxes of NH4 + were measured non-invasively using SIET (scanning ion-selective electrode technique), root respiration was measured using a Hansatech oxygen electrode and an oxygraph control system.【Result】(1) In the low NH4 + concentration range of 0-0.8 mmol·L -1, the uptake of NH4 + by QL and HK seedlings stage were in accordance with Michaelich-Menten equation, and the Vmax of high-NRE variety QL was 1.66 times higher than that of low-NRE variety HK. In the NH4 + concentration higher than 1 mmol·L -1, the uptake of NH4 + by rice seedlings kept increasing with the increase of NH4 +concentration, and the uptake rate of NH4 + by QL was greater than that of HK at the same NH4 +level. (2) The root meristematic zone of both varieties showed a net NH4 +influx, while it increased with the increase of NH4 + concentration, and the high-NRE variety QL had greater value than low-NRE variety HK by 42.0%, 71.8% and 63.6% at LN, MN and HN, respectively; The net NH4 +efflux in the root elongation zone was showed at LN and HN in the low-NRE variety HK, while it was only showed at HN in the high-NRE variety QL, and 34.30% lower than variety HK. (3) Although an appropriate increase of NH4 + could increase the plant height, tiller number, leaf chlorophyll content, dry matter and N accumulations, while HN inhibited plant growth, especially root growth. The growth of high-NRE variety QL did not show an advantage compared with low-NRE variety HK in the treatment of LN and MN, however, QL had greater tillering rate and dry matter accumulation rate by 65.7% and 31.4% compared with HK during 10-20 days after seeding in HN, respectively. Although the N concentration of root of variety QL was 15.1% lower than that of variety HK, it’s aboveground N accumulation was 23.5% greater, which indicated that QL was more efficient than HK in transporting the N absorbed by roots to the aboveground. 【Conclusion】 It was concluded that compared with the low-NRE variety, the high-NRE variety had more NH4 + transport carriers on the cell membrane of the root system, and the NH4 + absorbed by the root system had a fast assimilation and transport speed, as well as a high tiller rate and dry matter accumulation rate in the seedling stage.

Key words: rice, N absorption efficiency, ammonium absorption, NH4 + circulation, seedling morphology