Modification of Flowering in Cassava Using a Transgenic Approach

Flowering is the critical reproductive process in all angiosperms. Arabidopsis, a temperate species whose flowering behavior has been studied, provides a knowledge basis to harness developed tools for the control of flowering in Cassava. Flowering and its control in cassava, which is one of the most important breeding challenges, is not optimal because of "shy" and non-synchronized flowering. This results in an inability to use valuable genotypes in breeding from a trivial block in making F1 crosses. The Flowering Locus T (FT) gene, one of the many flowering genes identified in Arabidopsis thaliana known for its graft transmissible and mobile signal, was predicted as a good candidate for Cassava improvement. We placed this FT gene under the control of an ethanol-inducible promoter and this construction was introduced into the cassava variety 60444, which flower moderately through Agrobacterium-mediated transformation. Several independent transformation events were generated and molecular analyses confirmed the presence of the insert, promoter and the selectable marker. Our findings demonstrate that the FT gene not only accelerate the timing of flowering, but also increase the profuseness and longevity of the flowers in cassava.