In article ,
Iris Cohen wrote:
The present invention relates to a method for producing potato
tubers comprising grafting a potato plant as scion on a solanaceous
rootstock and culturing the resulting graft plant by hydroponics to form
aerial tubers. etc..."

One little problem. Tubers have thin skins and are designed to grow
underground, where they have a constant supply of moisture. The surrounding
earth keeps them from getting bruised. Also, potatoes exposed to light develop
green pigment, which ruins them.

As a software jock, I can tell you that it sometimes seems like the US
Patent Office no longer bothers to find out if something has long been
a common practice before issuing a patent -- they count on someone with
lots of money challenging the patent later. People have succeeded in
patenting techniques that were described in undergraduate textbooks and
distributed in open source software many years before, things so
obvious no one ever thought of patenting them. IBM publishes a special
journal of off-the-cuff ideas mainly so that these ideas will be in the
public domain and their lawyers will have an easier case should any
later be patented.

Decades ago, "topatoes", a tomato scion grafted onto a potato stock,
were sold in the kind of mail-order semi-scam that gardeners in winter
often can't resist. Needless to say, they aren't tremendously
productive of either tomatoes or potatoes, but they are kind of cool.
If you want a robust and totally useless potato plant, you can do the
reverse graft.

Grafts of solanaceous plants for research and specialized applications
have been common of a long time. IIRC, it was commercial practice in
areas with a particularly troublesome root nematode to graft tomatoes
onto a resistant rootstock of another species at one time.

Potatoes can be grown hydroponically and aeroponically, but if the
objective is to obtain food, it's ludicrously uneconomic, except maybe
in some future space station. It can be useful in developing virus
free strains and for other specialized purposes, however. Assuming
this patent isn't challenged by a large corporation with a stake in
potato cultivar development (are there any?) it will most likely just
cause pain and expense to university and government researchers in the
physiology and pathology of Solanum tuberosum.

On the other hand, maybe I'm being a bit too harsh. Maybe this patent
covers a unique and much superior method of getting aerial tubers for
some economic purpose, and is validly patentable. However, such methods
are usually put into the public domain by publications in journals for
use by all scientists, or kept in-house as a "trade secret" (legal term).

The effect of patenting can be to force people to develop alternative
methods or divert to other areas of research. There's also the
chilling effect, as seen in the software area -- developers have to
worry whether some fairly obvious method they come up with themselves
or read about in a magazine or journal can leave them open to being
stomped flat by a large corporation that notices their use of the
technique years later, even if they used it before it was patented
(this can be very hard to prove).

Note that one can patent, then put the patent in the public domain.
This has been done with a few important software patents, and the good
PR can be more valuable than the potential royalties. Certainly Big
Corporation stomping Three Guys in a Garage (or Cool Little Startup)
tends to be bad PR.

Anyhow, enough pontificating in the absence of information. I probably
shouldn't have had that last cup of coffee. ;-)