Effect of inorganic nitrogen and phosphorous on morphology, ion uptake and photosynthesis activity in Jerusalem artichoke plants under salt stress

Abstract

This study was conducted to explore the effects of adding different amounts of exogenous inorganic nitrogen (Ca (NO₃)₂ 1 mM marked as N1, Ca (NO₃)₂ 5 mM marked as Nc and Ca (NO₃)₂ 7 mM marked as N2) and inorganic phosphorus (NaH₂PO₄ 0.1 mM marked as P1, NaH₂PO₄ 1 mM marked as Pc and NaH₂PO₄ 8 mM marked as P2) on the physiological and biochemical processes of Jerusalem artichoke under salt stress (150 mM NaCl marked as S). Low N caused large inhibition on growth and net photosynthetic rates, while the increased applications of N and P alleviated the adverse effects. Data showed that applications of low or high concentrations of N or P largely inhibited plant growth, and the adverse effects were more evident under salt. Moderate concentrations of N and P (NcPc) caused significant increase in the accumulation of biomass, total N content and photosynthesis. Moreover, K⁺, Ca²⁺, and Mg²⁺ content were improved and Na⁺ content decreased in leaves at NcPc. Analyses of stem anatomy showed that vascular less developed and phloem partially detached at low N and P concentrations. Cells were orderly arranged and vascular well developed at high concentrations of N and P. The results suggested that moderate application rates of N and P improved growth through enhanced photosynthesis and sustain ion status especially Na⁺ and K⁺ equilibrium under salt stress. Our study provided valuable insights into strategies to manage N and P nutrition for crops in saline soils.

Keywords:

• Jerusalem artichoke plants
• nitrogen
• phosphorous
• photosynthesis
• salinity

Acknowledgments

The authors acknowledge the members of the laboratory for the assistance in this work.

Disclosure statement

There are no competing interests associated with the publication of this article.

Additional information

Funding

This work was financially supported by the [Forestry Science and Technology Innovation and Extension Project in Jiangsu Province] under Grant [LYKJ (2019) 07], [National Key Research and Development Program of China] under Grant [2016YFC0501207], [National Key Project of Scientific and Technical Supporting Programs funded by the Ministry of Science & Technology of Jiangsu Province] under Grant [BE2018387], and [Fundamental Research Funds for the Central Universities] under Grant [KYYJ201902, KYZ201623, YZ2016-1, and KYYJ201703].