Molecular Mechanisms of Early Flowering in Tomatoes Induced by Manganese Ferrite (MnFeO) Nanomaterials.

Nanomaterials (NMs) have demonstrated enormous potential to improve agricultural production. Ten mg L of customized manganese ferrite (MnFeO) NMs was selected as the optimal dose based on its outstanding effects on promoting tomato flowering and production. After the foliar application before flowering, MnFeO NMs increased the leaf chlorophyll content by 20 percent, and significantly upregulated the expressions of , , and in leaves, likely by serving as an electron donor, leading to a significant increase in photosynthesis efficiency by 13.3%. Long distance transport of sucrose was then confirmed by the upregulation of sucrose transporter and in NM-treated leaves and meristems. The genes associated with gibberellin biosynthesis, including , , and , and a flowering induction gene , were also significantly upregulated. Importantly, the flowering time was 13 days earlier by MnFeO NMs over the control. At the reproductive stage, MnFeO NMs increased pollen activity and ovule size, leading to the significant increase in fruit number per plant, single fruit weight, and fruit weight per plant by 50%, 30%, and 75%, respectively. Metabolically, a significant increase of glucose-6-phosphate, phenylalanine, rutin, and ascorbic acid (vitamin C), as well as a significant decrease of tomatine and methionine, demonstrates an increased nutritional value of the tomato fruits. A verified companion field experiment showed an increase of 84.1% in total tomato production with the MnFeO NM amendment. These findings provide support for the early flowering and yield improvement in nano-enabled agricultural systems.