Triploids are fertile-- was Another Lycoris question

Kenneth Hixson
Mon, 17 Aug 2009 12:25:19 PDT
Jim M wrote:
> with triploids stresses that to use triploid pollen is to court failure.

"Triploids are Fertile", by Nick Chase is an article that originally
appeared in the Spring 1994 issue of The Daylily Journal.
It was available online for a number of years, and perhaps still is--
a websearch on "daylilies-Triploids are Fertile", and/or with Nick Chase
also added, turned up lots of references to the article, but not the
article itself, unless it is included in the bloated PDF article you
can download from the AHS website.
Incidentally, many of the references you turn up on such a websearch
will state flatly that "You can't pollinate diploids with tetraploids,
or tetraploids with diploids"  This is nonsense, and such webposts
should be viewed with skepticism.  You can pollinate a fencepost--with
either diploid or tetraploid pollen.  Pollinating is not the same as
fertilization.  One of the greatest advances you can make is to do
something other people tell you is impossible--but you should be aware
that you may not succeed.  In fact, for an amateur, who often doesn't
have much room, making wide crosses may well be a good idea--fewer
seedlings will result, but they will potentially be more valuable.
Few amateurs have the room to grow thousands of seedlings to select
the best five or ten to serve as parents of further generations.

If you go to the Rose Hybridizers group and search for fertile
triploids, you find lots of references to roses which are confirmed
(by chromosome counts) triploids that are fertile, some as pollen
parents, some as seed parents, some with diploids, some with tetraploid
roses, some with either.

Lilium--I have a greenish yellow aurelian bowl which is from diploid
parents, and I have made a few pollinations with diploids (both as a
pollen parent and as a seed parent).  Last year a friend suggested I
make crosses of diploids with tetraploids in a deliberate effort to
produce triploids, which are often more vigorous and floriferous than
either diploids or tetraploids.  I had made a couple crosses with
diploids, so used tetraploid pollen on the remaining flowers.  To my
amazement, I got apparently normal fertilization, seed, and now,
seedlings with both diploid and tetraploid pollinations.  I've done the
same thing again this summer, and so far it appears that there will be
seed on this plant from both diploid and tetraploid pollen, and its'
pollen is likewise apparently fertile on both diploids and tetraploids.
  The "Experts" will tell you it is impossible--but it is happening.

The point is, men make rules--but the plants just keep on doing their
thing, which is trying to reproduce themselves.  They don't abide by
men's rules.  Each plant is unique, triploids are only sterile when
you give up.  One further example--there is a lily named Black Beauty,
which is a wide cross, and doesn't set seed.  For four or five years I
made as many as three hundred hand pollinations on it per year, and got
no seed.  Then, one year, I got about fifty seeds.  Repeating the same
crosses in the years following didn't yield any more seeds.
Unfortunately, at that time I didn't know how to do embryo rescue, and
the seeds were treated like normal oriental lilies, and none germinated.
I don't regard Black Beauty as sterile, although "everyone" says it is.

Incidentally, you are often admonished to "protect the cross", often by
covering the stigma with aluminum foil, paper bags, etc.  Geneticists
are particularly dogmatic about this.  Open Pollinated (OP) seed to
to some people is worthless. Here is a case where I would have been
happy to get seed--any seed, even if from something other than the
pollen I put on the stigma.  Even if the seed resulting was not from the
pollen I put on, it would have been better than no seed at all.  Not
knowing one parent isn't the end of the world.  Not knowing either
parent isn't the end of the world either--select seedlings for what they
are, not what their parents were.  Knowing the genealogy of the plants
is necessary if you are trying to produce theories, but the flowers are
just as pretty if you don't, and the plant may be valuable even if
the parentage is unknown.  Continuing to breed with such a plant is
still possible, and in fact is probably normal with many plants, where,
again with roses as an example, many named roses are the result of
open pollination anyway.  Even where the genealogy is known, seedlings
appear that were not expected, new traits show up that had been unknown.
What matters is what the plant can produce, not what the theory predicts
it will produce.  This is called "progeny testing" and it's a lot of
work, but it does work.


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