ZmGRAS46 negatively regulates flowering time in maize

Flowering time is an important factor limiting the planting area of maize (Zea may L.). Gibberellin (GA) can regulate plant flowering time by mediating the GA signaling pathway. This study screened significantly down-regulated gene ZmGRAS46 by early flowering mutant transcriptomic sequencing (PRJNA788070) in the previous laboratory. The expression pattern analysis of the ZmGRAS46 gene shows that it has the highest expression level in maize stems. The stem treatment with 200 μmol/L GA₃ resulted in the lowest expression of ZmGRAS46 at 3 h. Positive maize plants were obtained through the modified Agrobacterium-mediated genetic transformation of maize. The results showed that overexpression of ZmGRAS46 delayed the flowering of maize, and gene editing of ZmGRAS46 made maize blossom earlier. In addition, overexpression of ZmGRAS46 could increase maize 100-grain weight. This study provides new insights into the molecular mechanism of the GRAS gene in regulating plant flowering.