Stewart Robert Hinsley wrote:
: In message , Norman Digger
: writes
:: I've lots of small potatoes left over from last years harvest that
:: are shooting nicely. What is the wisdom of using them in place of
:: buying seed potatoes? Is there likely to be any downside to doing
:: this?
::
:: I vaguely recall doing this was the cause of the Irish potato
:: famine, since none of their potatoes were resistant to blight
:: because they never actually planted "seed" potatoes?
:: As a point of interest are Scottish seed potatoes actually the
:: result of growing potatoes from the seeds of potatoes?
:
: If you go back far enough all potatoes come from a seed, but the named
: cultivars are vegetatively propagated as tubers.
:
: The advantage of buying commercial seed potatoes, I'm informed, is
: that there is a lesser chance of tubers carrying pathogens.
:
: The Irish potato famine resulted, partially, from growing a
: monoculture of genetically undiverse potatoes, so one strain of
: blight could infect the whole crop. It seems to me that current
: commercial production is not that far different - 30% of the UK
: commercial crop is Maris Piper, which is a blight-susceptible variety.
::
:: Norman Digger.

I heard on GQT that Certified seed is grown above a certain altitude so
that aphids cannot introduce disease