Quote:
Originally Posted by Jeff214
...Starting material -> enzyme A -> intermediate product 1 (not red).
intermediate product 1 -> enzyme B -> intermediate product 2 (not red).
intermediate product 2 -> enzyme C -> red pigment (final product)....
If any one of those enzymes are not functioning properly, you may get low to no red pigment production (and an alba or aurea plant)....
Say if parent A has functional enzymes AB (alba/aurea) and parent B has functional enzymes BC (alba/aurea). The offspring might inherit functional copies of all the enzymes ABC (red). Just based on phenotype (what is looks like), you can't tell the genotype (the gene make up)....
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OK splain this. Pseuobombax ellipticum (formerly Bombax e.) is a Mexican tree in the cotton family Malvaceae (formerly Bombacaceae.) It has white flowers. Its closest relatives in Mexico are various members of genus Ceiba, also all with white flowers. There are Pseudobombax species in South America with white flowers, and several species of Ceiba in South America with flowers of white, pink and deep red. The pinks and reds look to me like anthocyanin reds, not lycopene reds.
Every Pseudobombax ellipticum seedling you can buy, and every of many trees I've seen in the wild in Mexico, has white flowers, and completely green leaves, without any trace of red pigment at any stage of development.
It is easy to recognize a tree grown from seed; they develop a very large, bottle-shaped base, at a very early age. Cuttings never develop the base, even when they get very big.
At each of the four corners of the main plaza in the town of Tehuantepec, in southern Oaxaca, grows a very old Pseudobombax ellipticum tree. They lack the bulbous bases, therefore are cutting grown. Each has deep red flowers. It is an anthocyanin red.
In a courtyard in Oaxaca, capital of the state, I have seen a smaller but flowering Pseudobombax ellipticum tree lacking a bulbous base, with the same deep red flowers.
I have also seen one in a courtyard in Mexico City, again without the bulbous base.
Pre-contact Aztecs were known to be avid gardeners. Many plants are known only from pre-contact gardens, like the tuberose, the chocolate daisy and many agaves. They knew how to root cuttings of tree branches. They did this to make fences from cuttings of various Bursera species, New World aromatic trees related to the Old World frankincense and myrrh.
There are reported to be several red-flowered Pseudobombax ellipticum examples growing in Florida. The one I saw lacked the bulbous base. The nursery owner grafts pieces of the red-flowering branches onto normal white-flowered seedlings with the aim of producing red-flowered trees with the characteristic large bases. I have two of these. The grafted portion produces new leaves that are completely maroon, then they turn dark green as they mature. I have allowed shoots from the understock to grow; they have bright green new growth that matures to a lighter shade of green than the piece grafter above. It is always possible to tell the two kinds of leaves apart.
So - How could this occur? I've asked a lot of botanists and not received any hypotheses. White flowers reflect pigment producing pathways not functioning. White flowers are typically recessive, and pigmented flowers the norm.
The species is self-incompatible. I don't know whether anybody has tried pollinating red with white-flowered Pseudobombax ellipticum plants, and the reverse, to see what happens. It is only about 5 years to flower from seed in a really wet climate. I can't do it because my winters are too cold for this plant, and I don't have enough inside room for multiple flowering-sized plants.
If it's only one locus, crossing siblings from a redxwhite grex should result in some red-flowered F2s. If it's more loci, continuing to line-breed future progeny with the red-flowered parent should result in all red-flowered plants.
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