On Wed, 21 May 2003 20:04:31 +0100, Victoria Clare
wrote:

"The Devil's Advocate" wrote in
:

F1 hybrids are pollinated manually under very strict conditions so
that there is no chance of cross over of pollen from another type of
that plant. That is why they are so expensive.

Not exactly. An F1 hybrid is a particular type of first generation
cross, not just a hand-pollinated plant.

Say I cross: short fat hairy one with tall thin weedy one

First generation of their children - all gorgeous tall slim ones - the F1
hybrids


Then I breed together two of my F1 hybrids.

Their children may be : tall and weedy, short and fat, tall and fat,
short and weedy etc...


F1 hybrids don't 'come true' when they breed together, because they have
a bunch of different genes that can combine in different ways - however
much you isolate them. Only the F1 generation will all have the same
combination of genes to produce the desired characteristics.

Lots of plants have characteristics that are not governed by one
'perfect' combination of genes. According to a bloke on the telly last
night, Aquilegia vulgaris Black Barlow fits this model - as do most
wildflowers, and pretty much any garden seed that comes in a big, cheap
bag ;-)

They have a bunch of genes that can combine in several different ways to
produce more or less the same results. You get the odd slightly
different one, but on the whole, the children look pretty much like the
parents - they 'come true from seed' without being F1 hybrids.

If you plant 'em next to something skyblue pink, you may get the odd
skyblue pink one. But if you get *all* weird looking skyblue pink ones,
which then go to a mixture the year after, you have created your own F1
hybrids!

Some plants are not F1 hybrids or 'true from seed'. They may be a
'selected strain' (like a labrador is a selected strain of dog), or they
may be a one-off freaks propagated by cuttings. Most fruit tree
varieties are freaks, which is why growing apples from pips is less
rewarding than reason says it should be.

HTH and that I've got it right!

Victoria

That's about right.

BTW "F1" stands for "first filial generation" which means it's the first
generation of offspring to be produced from a cross.
If you then cross these with F1s with each other, you'll get the F2
generation, which will in all probability produce a mixture of tall thin
hairy ones, short fat hairy ones and various other combinations, but most
likely resembling the original parent plants.

F1 hybrids marked as such on the packet are just marked so to warn you that
if you try and cross these plants, you're more than likely to just get
plants with the parent's features, rahter than the ones that you bought in
the packet.

If you want to know more, look up Gregor Mendel - a hungarian monk who was
one of the pioneers in quantifying crosses and heritable traits. Ok, some
of his results may have been "fiddled" abit, because they are suspiciouls
too close to the "ideal" but the principles apply, and his choice of peas
was a good one.

Tim.