Effects of Magnesium on nitrate uptake and sorbitol synthesis and translocation in apple seedlings

Bibliographische Detailangaben
Veröffentlicht in:	Plant physiology and biochemistry : PPB. - 1991. - 196(2023) vom: 15. März, Seite 139-151
1. Verfasser:	Tian, Ge (VerfasserIn)
Weitere Verfasser:	Liu, Chunling, Xu, Xinxiang, Xing, Yue, Liu, Jingquan, Lyu, Mengxue, Feng, Ziquan, Zhang, Xuelin, Qin, Hanhan, Jiang, Han, Zhu, Zhanling, Jiang, Yuanmao, Ge, Shunfeng
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2023
Zugriff auf das übergeordnete Werk:	Plant physiology and biochemistry : PPB
Schlagworte:	Journal Article Apple Magnesium NRT2 Nitrate absorb Sorbitol Nitrates I38ZP9992A Nitrogen N762921K75 mehr... 506T60A25R Sucrose 57-50-1

Beschreibung
Zusammenfassung:	Copyright © 2023 Elsevier Masson SAS. All rights reserved. Both magnesium (Mg) and nitrogen (N) play many important roles in plant physiological and biochemical processes. Plants usually exhibit low nitrogen utilization efficiency (NUE) under Mg deficiency conditions, but the mechanisms by which Mg regulates NUE are not well understood. Herein, we investigated biomass, nutrient uptake, sorbitol and sucrose transport, and relative gene expression in apple seedlings under various concentrations of Mg and N treatments in hydroponic cultures. We first observed that low Mg supply significantly limited plant growth and N, Mg concentrations. Increasing the supply of N, but not Mg, partially alleviated the inhibition of plant growth under low Mg stress, which indicated that Mg deficiency had a negative impact on plant growth because it inhibits N absorption. Moreover, we found that the expression of nitrate transporter genes MdNRT2.1 and MdNRT2.4 was significantly downregulated by low Mg stress, and sufficient Mg significantly promoted sucrose and sorbitol synthesis and transport from leaves to roots by regulating relevant enzyme activity and genes expression. Further experiments showed that exogenous sorbitol could rapidly restore MdNRT2.1/2.4 expression and nitrate uptake under low Mg availability without increasing internal Mg level, suggesting that Mg may regulate MdNRT2.1/2.4 expression by regulating more sorbitol transport to roots, the effect of Mg on N was indirect, sorbitol played a key role during this process. Taken together, Mg promoted sorbitol synthesis and transport into roots, thus upregulating the expression of MdNRT2.1/2.4 and increasing the absorption of nitrate
Beschreibung:	Date Completed 05.04.2023 Date Revised 05.04.2023 published: Print-Electronic Citation Status MEDLINE
ISSN:	1873-2690
DOI:	10.1016/j.plaphy.2023.01.033