In addition to providing colour to flowers and fruits,
carotenoids also contribute to the production of scents and
flavours that attract insects and animals for pollination
and seed dispersal. All photosynthetic organisms accumulate
carotenoids where they play crucial roles in photosystem
assembly, light-harvesting and photoprotection
[20,21]. Typically, leaf tissues accumulate lutein, b-carotene,
violaxanthin and neoxanthin (Figure 1), with
changes in this profile altering photosynthesis, antenna
assembly and photoprotection [21–23]. Carotenoids also
serve as precursors for plant hormones, abscisic acid (ABA)
and strigolactones (Figure 1) [6,24–27]. The strigolactone
class of carotenoid metabolites inhibit shoot branching and
stimulate a symbiotic relationship with fungi in the rhizosphere