Original mechanism for regulating inflorescence in rice discovered

Scientists have discovered in rice an original mechanism of inflorescence development that contradicts over a century of study and research: it is regulated by a molecular signal (florigen) that is not produced in the leaves, as previously thought, but directly in the shoot. Interrupting the mechanism results in increased flowers, seeds and therefore plant yield. The international research is published in Nature Plants and coordinated by Fabio Fornara of the Statale University of Milan.

The study demonstrates, surprisingly, "the existence of a florigen produced directly in the part of the plant that contains the stem cells and is responsible for the formation of the inflorescence," according to Fornara. This new florigen "contributes only minimally to establishing flowering time: its main function is to determine the number of branches of the inflorescence,” he continues.

Using mutant plants produced using chemical techniques or genetic editing, the researchers have shown that removing the gene from the plant causes a significant increase in the number of inflorescence branches, leading to an increase in the number of flowers. "This change in the plant's developmental plan is of particular importance from a biotechnological and genetic improvement point of view, as more flowers can lead to more seeds and thus to increased yields," Fornara adds. "In addition, the mechanism discovered in rice is conserved in other cereals in which it can be exploited to improve yields."