ZmYSL2 affects the physiological function of iron deficiency in maize.

Iron deficiency resulted in reduced sensitivity of the enhanced iron tolerance in maize o213 mutants, affecting pigment synthesis, photosynthesis parameters, sugar content, and iron distribution, with variable expression of the YSL gene. Iron (Fe) is a vital trace element for the growth and development of plants. A deficiency of this element results in the formation of yellow leaves. The present study demonstrated that a mutation in the ZmYSL2 gene resulted in reduced sensitivity of o213 mutant maize seedlings to Fe deficiency. The mutation resulted in a reduction in the content of photosynthetic pigments in the leaves, particularly carotenoids, and a decline in photosynthetic parameters. However, it is noteworthy that the soluble sugar content was increased. The mutant displayed increased iron accumulation in the roots and decreased accumulation in the shoots, accompanied by elevated iron content in the sap of the phloem. The expression pattern of the ZmYSL2 gene demonstrated a correlation between its expression level and the iron deficiency phenotype. In conclusion, the results of this study demonstrate that the ZmYSL2 gene plays a crucial physiological role in enabling maize to adapt to an iron-deficient environment.