The magnesium-specific uptake and translocation transporters ZmMGT10 and MGR6 are upregulated not only by magnesium deficiency but also by high potassium concentrations in maize.
Level 5 - mechanism / opinion, no new human data
Level 5 by design analogy (controlled laboratory plant experiment)
PubMed 40334516 · doi:10.1016/j.plaphy.2025.109977
What was done
Hydroponic experiments on young maize (*Zea mays* L.) were conducted to evaluate the response of the magnesium (Mg2+) uptake transporter *ZmMGT10* (*ZmMGT10;1* and *ZmMGT10;2*) and translocation transporter *MGR6*. Plants were exposed to eight distinct potassium-to-magnesium (K+/Mg2+) ratios to measure relative transporter RNA expression. In a second experiment designed to bypass uptake antagonism, plants were grown under sufficient versus deficient Mg2+ supply paired with adequate or excess K+ to evaluate whether elevated leaf [K+] impaired physiological Mg2+ functions, assessing chlorophyll, starch, and nutrient concentrations.
What was found
The abstract reports qualitative directions without numerical values or effect sizes. Expression of *ZmMGT10;1* increased due to lower root [Mg2+] induced by high K+. In contrast, *ZmMGT10;2* and *MGR6* expression increased under high K+ exposure independently of root [Mg2+]. Elevated tissue [K+] did not impair the measured physiological functions of Mg2+.
Why it matters
This study demonstrates specific molecular adaptation mechanisms in maize, indicating that upregulation of designated Mg2+ uptake and translocation transporters helps mitigate potassium-induced magnesium deficiency.
Limits
No sample sizes, replicate numbers, or quantitative values (transporter expression fold-changes, tissue ion concentrations, chlorophyll, or starch metrics) are provided in the abstract. The findings are limited to juvenile plants grown in an artificial hydroponic system and cannot be directly generalized to field soil conditions.
Cited by
- supports Modern NPK (nitrogen, phosphorus, potassium) fertilizers inhibit magnesium absorption in agricultural crops.