To increase b-carotene levels and simultaneously induce early fruit
production in sweet orange plants, we constructed a binary
vector, named HRP, containing both an intron-spliced hairpin
(ihp) b-CHX RNAi cassette and an FT overexpression cassette
(Figure 1a). We used this vector to transform seedlings via
Agrobacterium tumefaciens-mediated T-DNA transfer. The binary
plasmid pROK2-CsFT, which was previously generated in our
laboratory (for details see Data S1), served as the vector system
for transforming control plants in this work