Few plants are known to have ‘visibly’ luminescent senescent
leaves, e.g., Ginkgo biloba [39] or bananas [13], but FCCs were only
detected in the latter. The optical perception of de-greened leaves,
fruit (and flowers) helps guide the crucial interactions of plants
with insects, birds and other animals (see e.g. [40,41]). ‘Persistent’
FCCs, the newly discovered blue luminescent plant pigments, are
sources of optical signals [12–14], and may be useful as natural
molecular in-vivo markers and signals of ripening and of programmed
cell death.