Gesilla,

Ken can probably answer this more definitively, but I don't believe streaking has to do with two different leaf layers. The streaks you see in Ice Age Trail for example are all part of the L1 layer. The little bit of white you see around the middle in Striptease is the L2 layer in leaves. But usually the L2 layer is not visible.

I believe streaking is a genetic mutation, but not a "defect." Mutations or "sports" can occur naturally or they can be caused by chemicals used in the tissue culture process.

Streakers are unstable in the sense that a solid color eye may develop from the unstable genetics, and this eye will eventually dominate a plant if it is allowed to continue to grow. Instability means that during growth the chromosomes don't always divide in the same way producing the same characteristics. Lots of Hostas are unstable, not just streakers.

Variegated seedlings produced from Streaker pod parents (note that it must be the pod parent, not the pollen donor) may or may not be stable. Every variegated plant (except perhaps for Frances Williams) likely came from a streaked pod parent.

Here's a little streaking seedling that I have growing.
{{gwi:937377}}

This is Lakeside Knickknack x OP. You can see that the base leaf color is chartreuse with yellow and some cream colored streaking. Next year when this seedling emerges it may continue to streak or it may stabilize into a chartreuse leaf with a yellow edge or some other form of variegation. This is why you have to give seedlings several years of growth before you know what you've got.

I'm sure Ken will correct me if I've gotten anything wrong.

Steve

This is the most unscientific answer ever. I picture a streaked hosta and turning stable like it is a snow globe with many colors of snow flakes. Imagine if you could take a hosta leaf with a stable white edge, bordered with a thin stripe of bright green and a dark green center and shake it up like a snow globe. You would be randomly shaking all the colors all across the leaf. In time the colored flakes will settle. Maybe all the dark green flakes will fall and cover the other others. Maybe the white flakes will settle in the center. You can get many stable plants from a streaked plant. Stable is a relative term. This is not anywhere near a scientific answer but when it comes to this I prefer to just accept it as an example of how amazing and miraculous nature is. Steve's seedling is a great example. I am sure he planted that seed with hope, was amazed to see it grow and suprised by how it looks. Rob

i will answer you ???'s in caps ..

===>>>

What causes hostas to streak? GENETICS ... AND GOD KNOWS HOW MANY GENERATIONS BACK THEY CAN GRASP.. BEFORE THEY APPEAR ...

I know it has something to do with the leaves having two layers. IRRELEVANT .. THIS HAS TO DO WITH HOW IT APPEARS TO THE EYE.. IT HAS NOTHING TO DO WITH HOW IT OCCURS REGARDING THE GENETICS ...

Streaked hostas are considered unstable YES .. BECAUSE EVEN A GREEN PLANT... WILL 'THROW' A STREAKER EVERY 10,000 SEEDS OR SO.. MORE OR LESS.. PLUS OR MINUS...

yet streaked Hostas are the only reliable way to grow variegated seedlings. ITS JUST ABOUT CUTTING THE ODDS ... TO GET SOMETHING 'NEW' .. DO WE REALLY NEED AN IMPROVED GREEN HOSTA???

Are these variegated seedlings eventually going to become one color? UNPREDICTABLE.. BUT USUALLY ... DEPENDING HOW PROACTIVE YOU ARE IN 'CAPTURING' THE STABILIZED 'EYE' .. BY CUTTING IT OFF MOM

Are the seedlings then considered unstable? SEE ABOVE REGARDING YOUR OWN COMMENT THAT ALL HOSTA ARE UNSTABLE ...

Is streaking considered a genetic defect? NOPE ... IF SO.. THEN MY REDHEADED BOY IS DEFECTIVE.. DUE TO HIS GENETICS ... [neither parent or grandparent.. or great grandparent has red hair.. but there was 1 aunt and 1 uncle on each side .. so its not a defect ... just genetics .. who was that dude with the peas .. lol]

If so, what causes the defect, is it the environment? I SAID NO ABOVE ..

----->>>

i hope this simplicity gets you somewhere..

what steve said is absolutely correct.. on my cursory review.. but when peeps start talking like that .. my eyes tend to glaze over.. and i start to wish adult beverages were involved ... big kudos to the peeps who know and share the hardcore science .. but i need to dumb it down for myself.. so i can grasp the concepts .. w/o getting lost in the words ... AND REMEMBER IT ON SOME LEVEL ... and the key is remembering it in a form i can repeat it ...

each of my answers above.. could probably involve a 10 to 30 page thesis ... but i dont type well enough to fool with that.. and for the most part.. it would just turn you all into drunks.. lol ... e.g. one of the first streaked of any acclaim was Dorothy Benedict ... herb used to claim.. he grew 25000 seeds from the edged Frances Williams.. to get that one streaker ... so yes.. its possible a stable edged plant can 'throw' a streaker ... but really now.. who has 10 years to grow 25000 seeds??? [ACTUALLY I THINK BILL NASH TRIED IT SOME YEARS BACK.. SINE HIS NAME POPPED UP]

blah.. blah... blah..

hit me with the next question ...

ken

ps: sooo ... see if you can wrap your brain around this .... now days.. most of the streakers ... and new edges come out of TC ... in TC.. they use hormones.. to trigger dormant buds to grow off of crown material .... using herbs numbers.. in creating 25000 new eyes .. off of one piece of crown .... that crown will 'throw' a streaker ... so it is very similar to the whole seed issue .. and it falls back to the dna in that crown.. which is of course.. the dna in the seed from that plant.. plus cross pollination, if any ... ok.. i got myself.. where the scotch.. and how do i explain i need a nip at 1030am ... lol ...

Ken's answers are so much more entertaining than mine.

Steve

if i gave you pure science.. you wouldnt keep coming back .. lol ..

and dont think i have it readily available in my head ... there just comes a point where i dont care to know more ... and that is where i cut loose from the seedy fellows and seed growers ... just too much science ... all the power to them.. i just dont care ... [its right up there with debating philosophy .. WHO CARES]

i been mulling this... since the above reply ..

a lot of peeps.. seem to think that genetics varies over species.. but its really all the same concept ...

and once you can relate it to humans .. as in the red headed boy ... to me anyway .. things start making more sense ... and i am able to retain it on some level ....

to avoid being graphic.. in the creation of my son.. there was no mutation.. or defect which caused the red hair .... it was just floating in the gene pool .... just like that streaked plant ... whether by seed or TC ...

ken

BTW.. some obscure brain cell seems to recall that aden claimed to have nuked seed to come up with one of his spectacular plants .. and as far as i know.. that has been poo pahed endlessly ... anyone recall which from his book that hooked me??? maybe a twin brain cell will trigger ... was it GE ..???

I got several envelopes of seeds from streakers from Mr. Hosta (M&M hosta seeds, LOTG)) and Trudy from the Hosta Seed Growers forum, planted those and after throwing out a lot of greenies enjoy now looking at some mighty nice streaked seedlings. I will grow those and keep some, and do not bother thinking about the science behind it, if they will stay stable, simply have fun. I plan to do this again starting October, beats any winter by far. Perhaps I will teach my 8 year old gardening grandson how to hybridize, perhaps Fickle Blue Genes x Queen of the Seas, Heh?
Bernd

From Wikipedia:

Gregor Mendel is today recognized as the "Father of Modern Genetics" for his work with the cross breeding of pea plants..

Is that the guy, Ken?

yeah,... i was thinking mendelson.. but knew that wasnt right ....

now for the next important question.. been reading the old cadfael novels... really cool mysteries set in the 1100's ... by a british author..

and they keep referring to the pease fields.. whats that all bout.. lol ...

but apparently.. i digress ...

anyway.. wonder what mendel said about recessive genes .. and second.. would i care.. and third..would i remember it this time.. lol .. apparently red hair is recessive.. as is, i am guessing, the unstable streaker in hosta... see.. i coudlnt think of it this morning.. but i am reactivating.. temporarily.. braincells with useless information ...

once i pick red up from his late playdate.. i plan on hitting the scotch and trying to deactivate them again ...

ken

Since you asked, or almost did, about the fields, here is what is stated about their relationship to Cadfael's world:

"This monastic enclave is composed of the great church, an adjacent cloister, a separate and distinct abbot's lodging, a guest hall, an infirmary, various barns, stores, and stables, a cart shed, a mill, and Cadfael's freestanding workshop at the edge of his enclosed herb garden amidst extensive "pease" fields. "

Like the childhood rhymes "oats, pease, beans, and barley grow..." and then "pease porridge hot" ... just another way to spell "peas," I'm thinking.

I give the link to it below. Thanks for reminding me of this series of books. You might also like to take a look at another British writer, still at it, Alexander McCall Smith.

Here is a link that might be useful: The World of Brother Cadfael

who the heck taught the british to spell english anyway .. lol ...

ken

Hmmm, I defer to UKHostaman on such matters.

However, I'm thinking it was the Germans...who like longer words. IMHO, the Brits added the extra 'e' to 'peas' to keep it from being another four-letter English word.

How do you get this British monk involved when Gregor Johann Mendel (July 20, 1822 - January 6, 1884) was an Austrian scientist and Augustinian friar, German speaking?

Ken -- genetics aside, I have it on good authority that being red headed is a sign of CHARM and INTELLIGENCE. He doesn't also happen to be left handed does he -- another desirable trait!!!
Jan

Mendel and that british guy probably liked good beer, another desirable trait!