Re: A blonde bougainvillea
William Glover wrote:
>
> When Hurricane Georges passed this way in September 1998 with winds of
> 240kph/150mph, it blew away a large bougainvillea plant along my
> driveway, leaving only a shattered trunk 15cm/6in in diameter projecting
> about 10cm/4 in above the soil. This vigorous, tall-growing cultivar is
> sometimes known as B. 'Vicky' in the US horticultural trade, having
> variegated leaves (yellow with green edges) and bracts of two colours
> (white and magenta), the bracts of both colours often appearing on the
> same stem.
There > are now three branches 60cm/24 in long, and several smaller
ones, all
> heavily leafed.
>
> The new branches are yellow, except for a hint of green where they emerge
> from the trunk, which is normal with this plant, but all the many
> emergent leaves are entirely yellow, which is not although the newest
> leaves show a faint blush of green which disappears quickly when the
> leaves are a few days old.
One possibility is that this particular variety is a chimera, this means
that parts of the plant (in this case the pale areas) are genetically
distinct from others (the green areas). What will probably have happened
is that one particular gene or small group of genes connected with
chlorophyll production has become somehow turned off in some of the
cells. In the original plant with this variegation it most likely
occurred as a "sport" involving just a single shoot which some alert
breeder happened to notice and propagated from. It will have been kept
going since by growing cuttings. In these cutting-grown individuals
THROUGHOUT THE WHOLE PLANT some groups of cells will have a working
"green" gene and others will have one which is switched off. Of course
this will only be noticeable in parts which normally develop
chlorophyll, in other tissues the gene will not be actually working
anyway.
As to your blond shoots. What seems to have happened is that the cells
in your badly-damaged plant which have managed to start off new shoots
just happen to come from one of the no-green areas. If this is the case
they will never produce any chlorophyll and will eventually die off.
Unless some shoot can arise from either a green-only area (which will
give you a wholly-green plant) or from a mixed area (which will give you
back your variegated plant) I fear your Bougainvillea is probably doomed
in spite of making this gallant effort to survive.
Moira
Tony & Moira Ryan <theryans@xtra.co.nz>
Wainuiomata, New Zealand. (on the "Ring of Fire" in the SW Pacific).
Lat. 41:16S Long. 174:58E. Climate: Mediterranean/Temperate
