Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (7): 728-737.DOI: 10.17521/cjpe.2021.0155

Special Issue: 生态化学计量

• Research Articles • Previous Articles     Next Articles

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)


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