Around 180 genes have been found in Arabidopsis that control flowering time based on analysis of transgenic plants [1]. Most of these genes take part in the six main pathways controlling flowering; the photoperiod, vernalization and the ambient temperature pathways that respond to environmental conditions, while the age-dependent, autonomous, and gibberellin pathways involve a response to endogenous signals [2]. Flowering Locus T (FT) is a major gene involved in flowering in plants because FT encodes mobile florigen for floral induction. Mutation of the FT gene can result in delayed flowering. Using a transient CRISPR-Cas9 expression system mediated by virus expression, it is possible to do gene-editing in plants without incorporation of exogenous DNA. We aim to develop these approaches to manipulate flowering time in plants.

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C. R. Sari, J. Taylor, Y. Hong and S. Jackson, “Development of a transient viral CRISPR expression system to manipulate flowering time in plants,” International Journal of Applied and Physical Sciences, vol. 2, no. 3, pp. 65-70, 2016.