Environmental and Molecular Regulation of Flowering in Cultivated Strawberry (Fragaria x ananassa)

Abstract

Cultivated strawberry (Fragaria x ananassa) is a globally important fruit crop which shows promise as a candidate for various methods of controlled environment production. However, a better understanding of the mechanisms of the regulation of flowering is needed, as more frequent or consistent flowering would be advantageous in controlled production. It is well understood that flowering in F. x ananassa responds to both photoperiod and temperature, however, the mechanism behind this response is not fully understood, particularly in perpetually flowering cultivars. While some genes of interest have been identified, a more complete model has not been established. This is largely due to the complexity of the octoploid genome and a lack of current knowledge on the mechanism of temperature response in both seasonal- and perpetual-flowering F. x ananassa. A starting point for developing a better model of flowering response in cultivated strawberries lies in the simpler Fragaria vesca, which indicates a FvCO-FvFT1-FvSOC1-FvTFL1 module for control of seasonal flowering and a lack of functional FvTFL1 responsible for perpetual flowering. However, there are some key differences when discussing F. x ananassa's perpetual flowering characteristics. Recent studies have helped to elucidate some of these differences, allowing for a putative model of seasonal flowering in F. x ananassa, as well as indicating where further questions need to be asked regarding perpetually flowering cultivars.