Developmental stage-specific disruption of iron allocation by a ZmYSL2 mutation in maize

The ZmYSL2 mutation causes abnormal iron distribution in tissues of maize o213 mutants, disrupting iron transport during the V9/12D developmental stage while simultaneously reducing iron transport efficiency. Iron (Fe) is an essential nutrient for plants. This study demonstrates that the ZmYSL2 mutation alters the distribution of iron within plants. The iron content in the roots of the o213 mutant exhibited a peak at the R1 stage, yet remained significantly lower than that of G213 throughout the developmental process. The mutant exhibited a significantly higher kernel iron content in comparison to G213 at all developmental stages. However, iron content in both the embryo and the endosperm was significantly reduced. In addition, the correlation between iron content in source and sink tissues was reversed in the mutant in comparison with G213. The mutant roots and internodes exhibited a decline in Fe transport efficiency and content. Collectively, these results indicate that the ZmYSL2 gene is crucial for the normal coordination of Fe allocation between nutrient and reproductive tissues during maize growth and development.