Agriculture Reference
In-Depth Information
of a breeding clone for release as a cultivar. The
total time elapsed from the generation of true po-
tato seed until the determination of whether to
release a breeding clone as a cultivar generally
ranges from
12
to
14
years. This time frame is ne-
cessary for the collection of agronomic and dis-
ease/pest response data, the development of man-
agement guidelines, and the production of
sufficient certified seed. While seemingly a long
duration, an established breeding program has
breeding clones at all stages of development, with
cultivar releases occurring more frequently than
12-14
years. For example, the NPVDP annually
released one to four cultivars from 2007 to 2012.
Key to the decision making regarding the re-
lease of a new cultivar is industry feedback. As
mentioned in the previous section, processing
companies, as examples, will be collecting their
own agronomic, processing, and storage data on
advanced breeding clones relative to industry
standards even prior to release. The larger-scale
field, processing, and storage evaluations con-
ducted by industry may reveal weaknesses that
may not be observed in the smaller-scale evalu-
ations conducted by breeding programs—for ex-
ample, it is difficult for a breeding program to
mimic the large potato piles and the environment
typically found in commercial storage structures,
as described by Kleinkopf and Olsen (2003).
On the basis of research data and industry
feedback, a name is selected for a new potato cul-
tivar, and in the case of new cultivars to be re-
leased in Idaho, the state's Foundation Seed
Stock Committee is approached with a release
document that details the new cultivar and its
merit for release. Committee members review
the submitted release, and following discussion a
formal vote is taken for approval of the release of
the cultivar, with a formal document detailing
the new cultivar being released to the public.
Prior to the amendment of the Plant Variety
Protection Act in 1995, allowing for potato to be
included among crops eligible for protection,
potato cultivars were public releases, with no
stipulations concerning their use. Plant Variety
Protection (PVP) for potato allowed US breeding
programs to collect research fees or royalties for
the use of their protected cultivars, with all pro-
grams now applying for PVP for newly released
cultivars. The release of a new cultivar by a po-
tato breeding program was not generally accom-
panied by any promotion or marketing. However,
within the last decade, breeding programs such
as in the state of Colorado, as well as the Tri-State
program, have formed collaborations with grower-
supported marketing entities to promote culti-
vars released from those programs. A primary
benefit to the breeding programs is a greater
return of cultivar royalties to help support con-
tinued research efforts—important with the con-
tinued erosion of federal and state research funds
in support of potato breeding.
16.5 Conclusion
Traditional breeding allows for the genetic
“reshuffling” of genes and their recombination
into new genotypes that may carry the desired
assemblage of resistance and agronomic traits
necessary for release as a new cultivar. While
molecular biology techniques can be useful for
improving on a weakness in a cultivar, such as
improving resistance to blackspot bruise and
cold-induced sweetening (Rommens
et al
., 2006)
or late blight (Halterman
et al
., 2008), such
technology cannot currently be used in the de-
velopment of a wholly new cultivar, due to the
inability to pyramid all the necessary traits re-
quired by industry, many of which are quantita-
tive with no clear understanding of the genes
involved in their expression. Traditional breed-
ing therefore remains the primary source of new
potato cultivars, with a greater acceptance and
adoption of them by the potato industry. For
example, while Russet Burbank is still the pre-
dominant potato cultivar grown in the USA,
that cultivar has seen its acreage steadily
replaced by newer cultivars. Idaho's acreage of
Russet Burbank from 1992 to 2012 decreased
from 87.8% to 52.5%, with the cultivars, Russet
Norkotah (released in 1987) and Ranger Russet
(released in 1991), contributing to the decrease
in Russet Burbank acreage. Two of the top ten
cultivars grown in 2012 in the fall-production
states of the USA—these states representing
76% of total US potato acreage—represent cul-
tivars released within the last
15
years—Umatil-
la Russet (1998) and Alturas (2002) (USDA,
National Agricultural Statistics Service, Crop
Production, December 2012).
For potato breeders, greater efficiencies in the
development and mapping of molecular markers
