Agriculture Reference
In-Depth Information
8
Seed Potato Production
Robert D. Davidson
1
* and Kaiyun Xie
2
1
Department of Horticulture and Landscape Architecture,
Colorado State University, Fort Collins, USA;
2
CIP Beijing Liaison Office, Beijing, China
Potatoes are unique from many crops in that
they rely heavily on vegetative (asexual) propa-
gation for production rather than botanical seed.
Tubers are used as the primary reproductive unit
and are referred to as “seed potatoes”. Potato bo-
tanical seed is known as true potato seed (TPS)
and is used primarily for new cultivar develop-
ment, but is used occasionally in commercial
production. Seed potato tubers must be grown,
harvested, and stored properly to provide appro-
priate seed stocks for the following year's crop.
Growing a healthy seed stock entails a good
understanding of how tubers age physiologic-
ally and how diseases impact the tubers and sub-
sequent crops. Equally valuable is knowledge of
how producers purchase the highest quality, ap-
propriate seed stocks for their growing operations.
Potato tubers are either planted as whole
units (single-drop seed) or as cut seed, whereby
tubers are cut into seed pieces that typically con-
tain two or three eyes. Each eye houses axillary
buds and is the location from which sprouts de-
velop. By using whole or cut tubers, producers
are able to clone the original cultivar, which allows
them to produce potatoes with very predictable
traits. Cutting seed potatoes typically provides
an economic advantage to growers, especially
when tubers are too large to fit into a planter.
The use of vegetative propagation, however,
brings inherent problems into the system, including a
potential increase in diseases and difficulties in
maintaining varietal purity. Any disease-causing
pathogens present in the material used for propa-
gation are often transmitted to the progeny, thus
resulting in seedborne diseases. Also, the cutting
process can expose the cut surfaces of the tubers
to pathogenic organisms (de Bokx and van der
Want, 1987; Lambert
et al
., 1998). Until the cut
tuber is suberized and healed properly, open
wounds can provide the conduit for movement of
pathogenic organisms or can infect the seed piece
from either other tubers or external sources. It was
because of these inherent issues that certified seed
potato production systems were developed.
Healthy, productive seed that produces
solid, predictable yields of high-quality tubers is
the primary goal of certified seed potato produc-
tion systems. The effort to provide certified potato
seed to the worldwide potato industry that has
varietal purity and minimum levels of serious
disease-causing organisms has led to the devel-
opment of elaborate certified seed potato pro-
duction systems.
These certification systems rely on a series
of steps to verify cultivar identity, disease status,
and potential for approval as certified seed. The
certification process has seen many fundamental
changes in response to technological advances
that have allowed for more rapid multiplication
of potatoes under laboratory and greenhouse
