How Do Plants Decide When to Bloom?

Humanity long ago realized that the blooming of flowers, the colorful harbinger of spring, depends on the duration of the day and the tendency to change in temperature. However, we can say that the outline of the biochemical pathway puzzle of the process has begun to be completed thanks to current research.

In the 1930s, Soviet scientists thought that flower formation was triggered by sending a hormone produced in leaves to the shoot tip meristem. These cells at the ends have the potential to turn into leaves or flowers. Soviet scientists used this hypothetical chemical "fluorigen", which they thought initiated this process, but could not yet prove its existence.
gave the name.

Experiments with plants and rice of the Arabidopsis thaliana species, also known as mouse earcress, to find the mysterious flower-initiating chemical, yielded nearly eighty years after the concept of fluoride was introduced. Inoculation experiments demonstrated that the protein produced by the gene called "flowering site T" (FT) acts as a bloom signal. When the researchers inoculated a plant that lacked the FT gene and therefore could not bloom into a healthy strain, they found that the protein was transported to the plant with the missing gene, initiating flowering. Similar results in species with distant biological kinship show that the bloom-initiating feature of FT is valid for all flowering plants.

Later, some researchers focused on the biological clock mechanism that leads to the activation of the FT gene. The light-sensing protein FKF1, found in plants, is produced from late afternoon to late evening. Since there is not enough sunlight during the short winter days when this protein is produced, the protein cannot be activated. However, as the days get longer, the longer interaction of the FKF1 protein with light activates the FT gene.

When the FT messenger reaches the shoot tip, which is the growth zone, it conveys the message that the days are getting longer to regulatory genes such as LEAFY and Apetala1. Subsequently, the process of leaf production at the tip is stopped, and the functioning of hundreds of genes that enable flower formation begins.

Plants are thought to use HDA9, PWR and AGL 19 proteins to control their usual flowering time. Although it is known that regular changes in the ambient temperature in addition to the daytime period are effective in the beginning of the flowering process, the molecular mechanism of these processes has not been clearly understood yet.

Scientists think that by better understanding and controlling this mechanism, methods to accelerate or delay flowering can be developed for producers. It is assumed that this will pave the way for more productive harvest periods.

Posted with STEMGeeks