On Mar 20, 10:32�am, "James Silverton" >
wrote:
> �Steve �wrote �on Wed, 19 Mar 2008 21:38:14 +0000:
>
> �??>> Would you please expand on "totally different clonally" ?
> �??>> It has no obvious meaning to me.
>
> �SS> I mean that the clones of Zin in California may be similar
> �SS> to each other, but not closely related to the clones of
> �SS> Pimitivo in Italy.
>
> �SS> �Zin and Primitivo have a common ancestor, but clonal
> �SS> selection in California and Italy could have effectively
> �SS> produced two very different grapes for practical purposes.
> �SS> In the same way that Pinot Blanc and Pinot Gris are
> �SS> practically different for example, despite the fact that
> �SS> they technically belong to the same variety.
>
> �SS> It's pure speculation that the clones are very different,
> �SS> but I bet they are not the same clones both sides of the
> �SS> Atlantic. �As far as I know no one has done the research.
>
> �SS> But it could be that the differences between California Zin
> �SS> and Italian Primitivo might not be totally down to terroir.
>
> I am still rather puzzled. A clone in genetics is an exact
> replica. Cloning, in horticulture and biology, produces an
> organism whose genetic information is identical to that �from
> which it was created.
>
> I would suspect that it is usual to grow new vines of Pinot
> Blanc and Pinot Gris etc. from cuttings. In this case, the DNA
> sequence for two cuttings is identical even if growers may try
> to select for a particular characteristic. I don't know how you
> can achieve this asexually. Genetics seems to be taking a
> beating :-) Since "clonality" is described as the ability to
> form clones or the ability to be cloned, it does not seem to
> describe a process of selection that might produce different
> varieties.
>
> James Silverton
> Potomac, Maryland
>
> E-mail, with obvious alterations:
> not.jim.silverton.at.verizon.not

Did you read Bill's link to the WLDG discussion with Carole Meredith's
explanation? " All clonal variation, on the other hand, arises as a
result of rare and random somatic mutations (i.e., not sexual) that
occur in all vines. Sometimes such a mutation has a visible or
otherwise detectable (e.g. aroma difference) effect and a vine
carrying it will be preferentially used for propagation wood for new
vineyards. But often it is just chance that one mutation survives to
the next generation of vineyards and another doesn't. The mutations
accumulate over time and eventually clones diverge from each other."