November/December 2019 - 15

Seed Potato Directory, posted on the
Idaho Crop Improvement website
(www.idahocrop.com).
Seed buyers should be reminded that
the nomenclature used to describe Idaho
seed potato generations was changed to
a " field year " system, effective with the
2019 crop. This nomenclature is similar
to that currently used by a number of
other certification programs and is
intended to promote standardization
and transparency within the seed potato
industry by designating
generations
by the actual number of years that the
seed has been produced in soil. Please
note that there are no changes to the
tolerances associated with the various
field generations.
- Alan Westra, Southeast Area Manager,
Idaho Crop Improvement Association
COLORADO
The 2019 growing season was a bit
cooler than normal in Colorado.
All field-grown certified seed in
the state is produced in the San Luis
Valley in south central Colorado at an
elevation of 7,600 feet. It was preceded
by an above-average snowpack in the
mountains surrounding the valley,
which was a welcome change from the
record-setting drought last year. Seed
inspections started June 25, which was
one week later than last year.
Certified seed growers began killing
vines in late July and continued through
early August, limiting potential spread
of virus by late season aphid flights. All
potato seed acreage was harvested by
Oct. 20. Overall yields and sizing have
been average or slightly below average,
due in part to the cool spring and
summer weather.
Certified seed growers have
submitted their seed samples for
state-required post-harvest testing,
which takes place in Oahu. Certified
seed potato acreage was down overall
from 8,813 acres in 2018 to 6,756 acres
in 2019. The 2019 accepted certified
acreage after summer field inspections
was 6,180 acres.
Rejections were
primarily the result of PVY/mosaic,
with a few rejections caused by blackleg
and variety mix. Total potato acreage -
both certified and commercial - in the
San Luis Valley was 48,573 acres, down
from 51,785 acres in 2018.
Spudman * November/December 2019
13
The 2019 top five certified varieties:
* Russet Norkotah selections, 1,893 acres
* Canela Russet, 548 acres
* Teton Russet, 371 acres
* Alegria, 266 acres
* Centennial Russet, 231 acres
A wide range of potato varieties are
certified in Colorado including multiple
varieties of russets, reds, yellows,
chippers, fingerlings, and specialties.
Colorado requires all seed lots
imported into the state to undergo a
post-harvest test or winter grow-out.
Also, a PVYN tolerance of 1.0% is in
place for all imported seed. If you are a
seed grower intending to ship seed
into Colorado, contact your certifying
agency for submitting samples for postharvest
testing.
Also, there is a late blight quarantine
in effect for all seed coming into the
San Luis Valley. If you are planning on
shipping any seed into the valley, this
test needs to be conducted by a qualified
lab prior to shipment.
See potatoes.colostate.edu for testing
specifics and an official certified seed
directory.
- Andrew Houser, manager, Colorado
Potato Certification Service
http://www.idahocrop.com http://potatoes.colostate.edu
November/December 2019

Table of Contents for the Digital Edition of November/December 2019
