HYB: pumila genes into TB's [was: Re: SEED: Blue beard D Ferguson]

The challenge of getting *pumila* genetics into TB's intact would seem to
depend on cross-overs between paired chromosomes, one from the dwarf x=8,
the other from the tall x=12.  I don't know if any two chromosomes would
have sufficiently long sequences of bases in the chromosomes to allow any
pairing to make this a possibility.

One alternative is for fragments from *pumila* chromosomes ending up mixed
into or attached to those from the x=12 set.  The phenotypes would be hard
to predict or recognize, I would think.

I suspect the easier route (itself not at all easy!) is to find the
sequence(s) responsible for the blue beards in *pumila,* extract those in
the laboratory and insert them into a TB chromosome then tissue culture the
result.  That is a "megabucks" route, but one that has potential.  The
techniques do exist.

The trouble is, genetic sequences with the enzyme/catalysts they code do
what they do in a context within the entire genome of any one species.  A
blue beard sequence from pumila transplanted into TB's might not give a blue
beard at all.  The enzyme(s) may end up doing nothing, or even getting in
the way and altering the sequence of pigment synthesis in the TB, giving
completely unexpected results.

One hopeful sign is the existence of amphidiploid SDB hybrids where the blue
beards develop with great intensity and which also do give IB's of
12.12.12.8 makeup that not only have a degree of fertility, but also retain
the blue beard.  Unfortunately, crosses from these to 12.12.12.12 co-parents
are likely to lose the x=8 set entirely and simply produce more TB's.  It is
still worth a try.  What's there to lose?

The *aphylla* blue beard which we already have present in the TB genome(s)
is an easier route to blue beards.  In the post in response to Bill
Burleson's comment about JAGUAR BLUES, I've referred to a number of very
modern, high quality dominant whites.  The main problem is that those with
the most blue in the beards also have enough penetration of blue pigment
through the inhibitor to be classed as light blues, not whites, despite
their genetic "white" status.

If one could get BOTH the *aphylla* and the *pumila* blue beard genetic
sequences into a TB, some interesting effects would likely result.
Potential parents abound, ready made for the attempt.

Neil Mogensen  z 7  Reg 4  western NC mountains.

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