植物生态学报 ›› 2021, Vol. 45 ›› Issue (7): 728-737.DOI: 10.17521/cjpe.2021.0155

所属专题: 生态化学计量 根系生态学 菌根真菌

• 研究论文 • 上一篇    下一篇

丛枝菌根真菌与氮添加对不同根形态基因型水稻氮吸收的影响

马炬峰1,2, 辛敏1,2, 徐陈超1,2, 祝琬莹1,2, 毛传澡2, 陈欣2, 程磊1,2,*()   

  1. 1浙江大学生命系统稳态与保护教育部重点实验室, 杭州 310058
    2浙江大学生命科学学院, 杭州 310058
  • 收稿日期:2021-04-22 接受日期:2021-05-20 出版日期:2021-07-20 发布日期:2021-10-22
  • 通讯作者: 程磊
  • 作者简介:* lcheng@zju.edu.cn
  • 基金资助:
    国家自然科学基金(91951107);国家自然科学基金(32025024);中央高校基本科研基金(K20200026)

Effects of arbuscular mycorrhizal fungi and nitrogen addition on nitrogen uptake of rice genotypes with different root morphologies

MA Ju-Feng1,2, XIN Min1,2, XU Chen-Chao1,2, ZHU Wan-Ying1,2, MAO Chuan-Zao2, CHEN Xin2, CHENG Lei1,2,*()   

  1. 1MOE Key Laboratory of Biosystems Homeostasis & Protection, Zhejiang University, Hangzhou 310058, China
    2College of Life Sciences, Zhejiang University, Hangzhou 310058, China
  • Received:2021-04-22 Accepted:2021-05-20 Online:2021-07-20 Published:2021-10-22
  • Contact: CHENG Lei
  • Supported by:
    National Natural Science Foundation of China(91951107);National Natural Science Foundation of China(32025024);Fundamental Research Funds for the Central Universities(K20200026)

摘要:

植物主要依赖自身根系从土壤中获取矿质养分; 具有不同根形态的植物对于养分的吸收能力存在差异。丛枝菌根真菌(AMF)能与陆地植物根系形成共生关系, 帮助植物吸收矿质养分。但是, AMF对于植物根系养分吸收的促进效应是否会受根形态的影响还鲜有研究。该研究选取4种不同根形态基因型水稻(根毛缺陷突变体rhl1、侧根缺陷突变体iaa11、不定根缺失突变体arl1和野生型Kas)为研究对象, 设置2种施氮水平处理(低氮: 20 mg·kg-1氨氮; 高氮: 100 mg·kg-1氨氮), 利用稳定同位素15N示踪标记技术, 探究AMF和氮添加对不同根形态植物氮吸收的影响。研究结果发现, 相比低氮处理, 高氮处理下, rhl1、Kas、iaa11arl1的茎叶15N浓度分别提高了60%、72%、128%与118%, 说明氮添加显著促进了水稻氮吸收, 且iaa11arl1对氮添加的响应更强烈。在低氮水平下, AMF对rhl1、Kas、iaa11arl1氮吸收的平均效应值分别为17%、31%、42%、51%, 表明AMF对于植物氮吸收的促进效应受根形态影响, iaa11arl1对AMF的响应明显高于Kas与rhl1; 相较于低氮水平, 高氮水平下AMF对于不同根形态水稻氮吸收的促进效应都会显著降低, 表明氮添加削弱了AMF对植物氮吸收的促进效应。该研究阐明了4种不同根形态基因型水稻氮养分吸收存在显著差异, 其中氮吸收能力较弱的基因型水稻对AMF的响应更强, 该结果补充了植物与AMF在养分吸收上存在功能互补的控制实验证据。

关键词: 丛枝菌根真菌, 氮添加, 根形态, 氮吸收, 功能互补

Abstract:

Aims Plants absorb mineral nutrients such as nitrogen (N) mainly through their roots. The nutrient uptake of plants with different root morphologies differs. Many studies have shown that arbuscular mycorrhizal fungi (AMF) can help their symbiotic associates absorb mineral N. However, there is little research on whether the effect of AMF on nutrient uptake of plant roots is affected by root morphology.

Methods In this study, we selected three rice mutants and one wild type (root hairless (rhl1), lateral rootless (iaa11), adventitious rootless (arl1) and wild type (Kas)) to investigate the role of root morphology in plant nutrient uptake. Subsequently, we used the 15N isotope labeling method to explore the effects of arbuscular mycorrhizal fungi and N addition (low N: 20 mg·kg-1 NH4+-N; high N: 100 mg·kg-1 NH4+-N) on N uptake of rice mutants with different root morphologies.

Important findings The results show that the leaf 15N concentrations of rhl1,Kas, iaa11 and arl1 were increased by 60%, 72%, 128% and 118%, respectively, under the high N compared to the low N treatment. This result indicates that the addition of N significantly promoted rice N uptake with the most evident effect occurring in iaa11 and arl1. The average effect sizes of AMF on rhl1, Kas, iaa11 and arl1 were 17%, 31%, 42% and 51% under the low N level, indicating that root morphology can alter the effect of AMF on plant N uptake. Compared to the low N treatment, high N significantly downregulated the AMF effect on N uptake by rice plants with different root morphologies, indicating that N addition may mediate the complementary effect of AMF and root morphology on plant nutrient uptake. In conclusion, our data provide direct experimental evidence of funcitonal complementarity of mycrrohzal fungi and their associated roots with different root morphogy.

Key words: arbuscular mycorrhizal fungi, nitrogen addition, root morphology, nitrogen uptake, functional complementarity