Seeking Sex Info..Grape Sex That Is..(short/XXX/no pix)

Not much on biology...so way out of my area of expertise here, only know neutrons.
Supposedly, grapes are hermaphroditic..stamens and pistels and all that stuff I don't understand. But they are self-polinating and I gather this pollen falls off the stamen onto the pistel, the earth moves, and...voila...a grape is born. Pretty exciting...so they say.
The variety Picolit was nearly driven extinct be a so-called malady known as "floral abortion", where the flower would form, and then drop off and never produce a berry, resulting in absymally low yields. My understanding is that "floral abortion" is not a disease, but simply the fact that Picolit is sterile and will not self-polinate. So, it is necessary to interplant Verduzzo or something amongst the Picolit to provide the pollen for Pilicit to germinate into a berry. I gather this pollen is spread by the wind or on the feetsies of the bees out there in the vnyd.
I was reading about Timorasso (a very interesting wine from the Piedmonte, somelike a fruity
Arneis is how I would describe it) and that it also suffers from "floral abortion", which I presume implies that Timorasso is also sterile.
So a few questions here:
1. Are there other varieties in the wine world that are sterile?? And they would be??

2. Does the PiculitNeri that is grown in Friuli also suffer from being sterile? What varieties
are interplanted, if it does??

3. If the pistel of a flower is pollinated by the pollen from another variiety, rather than it's own
stamen; is the resulting berry the same as if it were pollinated by its oown stamen?? If it is different, that implies that Picolit interplanted w/ Verduzzo would differ from Picolit interplanted with PinotGrigio. Or is there much more incestuous fornication going on out there in the vnyd than I realize?? How close must the interplantings of Verduzzo with the Picolit be to get a good set?? What kind of yield can you get off Picolit by this interplanting?
I suspect the cross pollinated grapes must be different then self-polinated. As I recall, when HaroldOlmo was developing his crosses, he would put a big baggie over the flowers of one variety and then spread the pollen from the other variety inside the baggie (wonder if the earth moved for Olmo when he was doing this?) and then propagated the crossed variety from the seeds of the resulting grapes. Sound pretty tedious to me.

4. As I understand it, if you have high winds and rains during the flowering, you get a poor set and a resulting low yield. Is this because the the pollen gets scattered hither & yon and doesn't hook up with the pistel like it's supposed to?

Sorry...probably one of today's more esoteric posts...but sorta curious.
Tom

I can't answer most of your questions but concerning

If the pistel of a flower is pollinated by the pollen from another variiety, rather than it's own stamen; is the resulting berry the same as if it were pollinated by its oown stamen??

I believe the answer is the berry is the same. The seed is different but that does not impact the fruit nor the resulting wine.

My response to a post on another board:

John,
I think Robin is just repeating the story of "floral abortion" that is prevalent in nearly all the literature that you read about Picolit. I believe Robin is incorrect.
When I was doing the original article in 1981 in Vintage magazine, I talked at some length w/ HaroldOlmo. He cites research of DrGiovanni Cargnello at the Conegliano Institute. That research indicates that Picolit is a variety that is purely female flowers and, thus, is not hermaphroditic or self-polinating. Thus Picolit is not suffering from this mysterious malady of "floral abortion" that it somehow developed, but is merely a sterile variety.
Olmo suggested to me how this "floral abortion" malady evolved. Most of the early Italian plantings were field blends w/ much interplanting of of varieties who could provide the pollen to the Picolit. Thus the sterility of Picolit was not apparent. As the Italian vnyds moved to the more modern practice of planting varieties in blocks, the sterility of Picolit became obvious and they thought it was some disease, which they labeled "floral abortion".
At Conegliano, they developed a Verduzzo/Picolit cross that was self-polinating. DarrellCorti is of the opinion (gasp...Darrel Corti..an opinion!!) that most of the Picolit from Friuli is not true Picolit, but the Verduzzo/Picolit cross.
Hopefully, CaroleMeredith will be chiming in her to answer all my sex questions (well...maybe not all of them!!)
If you want a copy of my Vintage magazine Picolit article, I can send you one. Or anybody else, for that matter.
Tom

Tom,
Picolit is not the only variety that isn't self-pollinating. Supposedly, Fiano (di Avellino or otherwise) gets its name from "apiano" because it requires bees for its pollination. From this, I would surmise that there are both male and female Fiano vines. In the case of Picolit, I would guess that at some point in its history it was reduced to a very small population where, as population statistics would have it, all members were female.

Mark Lipton

I don't know about this a particular variety, but I understand that it is not necessary for a grape flower to be pollinated at all in order for it to develop a grape.

I read an experiment where the flower stalks were covered with a bag before the flowers developed so pollination could not occur and yet grapes appeared.

I don't know about this a particular variety, but I understand that it is not necessary for a grape flower to be pollinated at all in order for it to develop a grape.

I read an experiment where the flower stalks were covered with a bag before the flowers developed so pollination could not occur and yet grapes appeared.

I don't think I understand. Bagging the stalks before flowering would just ensure that no external pollen could fertilize the bunch. It should have a limited effect on the pollen of the flowers in the bunch and if most grapes are self polinating and do not need outside pollen then the result is not unexpected. What am I missing? Why would this bagging be expected to impact pollination?

Good point, Brian. I'll have to find the source....

I think when it comes to self-pollination, a lot has to do with the shape and size of the flower, and how the stamens (male sex organ) are positioned and angled around the pistil (female sex organ).

Salute

Not sure if this answers your question, Tom, but in the wild, Vitis vinifera sylvestris, the original Old World grapevines were either male or female. Each are non-grape producing. The only way for them to produce grapes is for the male pollen to make its way to the female flower--by wind, insects, or whatever.

Speculation is that thousands of years ago, farmers noticed a few grapevines that were consistent producers. These were anomalous vines, yet the farmers began to rely on them and started planting cuttings of them, which established the self pollinating grapevine, Vitis vinifera sativum.

Picolit is supposedly a wild vinifera, and so it cannot self pollinate. The only way it could have survived all these centuries is by some of the male and female vines actually pollinating each year--and Picolit is in fact a low, low grape producer in any year. Maybe it is pollinated now by other varieties nearby or maybe there are a number of anomalous Picolit vines that are self pollinating.

in the wild, Vitis vinifera sylvestris, the original Old World grapevines were either male or female. Each are non-grape producing.

You must mean that they are each non-grape producing on their own, I suppose? Surely the females are grape producing, after proper pollination from the males, as you also wrote.
Except for that I totally agree with your description.
Cheers, Anders

Yes, Anders, I thought I made it clear with the sentence that followed, but I should have said it this way:

"The only way for them to produce grapes is for the male pollen to make its way to the female flower--by wind, insects, or whatever--and the female then produces a crop."

In any case, the real error I made is that the sentence should read, "Each IS non-grape producing..." Singular/singular--shame on me!