February 2019 - 13

specimen and treat it to make certain it
harbors no disease. The resulting potato
stem is then cut into several segments,
which are placed in petri dishes filled
with growth medium to generate new
plantlets. The process is repeated until
the original stem has given rise to tens
of thousands of plantlets.
UI pots some of its tiny plantlets to
produce mini-tubers, known as prenuclear
seed. Other plantlets are sent to
other seed producers, such as Atchley,
who have the facilities to produce their
own mini-tubers.
Inside Atchley's greenhouse, located
5 miles east of Ashton, each plantlet
gets its own 9-inch pot. For the first
four days, plants are watered every
20 minutes by an overhead irrigation
system. Once the plants grow above
the rims of their containers, Atchley
applies systemic insecticide and time
release fertilizer, and she finishes
filling each pot with additional soil to
yield more mini-tubers. She plants her
greenhouse during the second week
of April and harvests in late August
or early September, using a special
table to separate the mini-tubers from
" I call it the annual miracle that this little,
tiny thing the size of a sewing needle with
three or four leaves will start to grow and turn
into a full-sized potato plant. "
- Emma Atchley, Atchley Farm
the soil before packing them in boxes
and storing them in a cool and humid
environment.
" I call it the annual miracle that this
little, tiny thing the size of a sewing
needle with three or four leaves will
start to grow and turn into a full-sized
potato plant, " Atchley said.
She pots between 10,000 and 20,000
plantlets each spring, based on her
projection of seed demand three to
four years into the future, allowing for
time to expand seed until it's ready for
sale either to commercial growers or
other seed growers who don't start as
early in the process. Every square foot
of greenhouse space she plants yields
about a pound of mini-tubers.
After a long dormancy period, the
mini-tubers are poised for rapid growth
the next spring, when she plants seed
in the field for the first time, known
as the nuclear generation. Atchley
typically plants 10 to 15 acres of nuclear
seed - she plants about a third of the
nuclear seed in Ashton and contracts
with a North Dakota farm to raise the
remainder, due to concerns about
increasing disease pressure from aphids
in her own growing region. The next
season's seed expansion is considered
the first generation. Commercial
growers usually buy third- or fourthgeneration
seed.
Maximizing Potato
Yield Starts at Planting
We can give you the harvest details with a yield monitor
RiteDepth - Automatic Depth Controller
Sonar Sensor Technology For More Uniform Planting Depth
* Uniform seeding depth is important to achieve uniform
emergence which will in turn help with timing and effi cacy
of spray & fertilizer applications.
* Sonar sensors improve uniformity while reducing the need
for frequent adjustments.
* Sonar sensors are small, out of the way, allowing a clear
view of the planter and cause no obstruction to stubble
and trash from previous crops.
For more information visit greentronics.com or contact us at 519-669-4698
As a leader in precision agriculture systems we off er unique solutions
specifi cally designed with the root and vegetable producer in mind.
Spudman * February 2019
13
http://www.greentronics.com
February 2019

Table of Contents for the Digital Edition of February 2019
