Agriculture Reference
In-Depth Information
For gene bank managers, a workable taxonomy
of the material they maintain is crucial, and the
presence of competing classifications is problem-
atic. Gene bank managers, who usually observe at
least part of their material during yearly reju-
venation cycles, get to know the species quite
well, but do not have enough time and resources
to be able to decide on taxonomic controversies.
So, how should gene banks deal with competing
taxonomies? It is virtually impossible to choose
the “correct” classification, and practice has
shown that taxonomists are not likely to recon-
cile their views. The only practical solution is to
record the name under which the material was
originally collected and add later taxonomic
opinions in additional fields in the database. In
this way, it is possible to cross-reference alterna-
tive names in gene bank databases. However, it
would be advantageous if some kind of stand-
ardization could be arrived at.
A new situation has arisen recently, now
the Solanaceae Source website has provided a
recent, comprehensive taxonomic treatment of
the species to be recognized in section
Petota.
Es-
pecially, the fact that this new taxonomy has
been adopted by the Germplasm Resources In-
formation Network (GRIN, 2014) may have the
desired effect of standardization, although gene
banks, by their own admission, are conservative
in accepting name changes; see, for example, the
website of the CGN, the Netherlands, where cer-
tain changes proposed by the Solanaceae Source
website have not yet been adopted.
produced a wide variety of cultivars, and the
crop spread over the rest of the world. Here, we
look briefly at the history of the taxonomic clas-
sification of the cultivated potato and discuss re-
maining problems and the current situation.
A brief outline of the history of the
taxonomy of the cultivated potato
Because of its importance as a crop, the culti-
vated potato has attracted the attention of sci-
entists since its arrival in Europe at the end of
the 16th century, and there is a huge amount
of literature describing the history of its tax-
onomy. Hawkes (1990) gives a chronological
table listing the early records and pre-Linnean
descriptions. Ovchinnikova
et al
. (2011) sum-
marize the historical developments in the clas-
sification of the cultivated potato, starting with
Linnaeus (1753), who included the potato as
Solanum
tuberosum
L. in his
Species Plantarum
,
probably based on material that was still closely
similar to the cultivated potatoes grown in South
America, later designated as
Solanum andigenum
Juz. & Bukasov and
S. tuberosum
subsp.
andige-
num
(Juz. & Bukasov) Hawkes. Russian taxon-
omists divided the crop into up to
18
cultivated
species and described hundreds of infraspecific
taxa (subspecies, convarieties, varieties, and
forma). Also, the Peruvian taxonomist, Carlos
Ochoa, published numerous infraspecific taxa
for cultivated material, recognizing varieties and
forma to accommodate the landraces of Bolivia
(Ochoa, 1990). Dodds (1962), observing the
lack of morphological support of the cultivated
species, maintained only the hybrids
Solanum
×
curtilobum
and
Solanum
×
juzepczukii
at the
species level and proposed five groups within
S. tuberosum
: Group Stenotomum (
2×),
Group
Phureja (
2×),
Group Chaucha (
3×),
Group Andi-
gena (
4×),
and Group Tuberosum (
4×).
The
standard treatment by Hawkes (1990) lists
seven species:
Solanum ajanhuiri
Juz. & Bukasov,
S. chaucha
Juz. & Bukasov,
S. curtilobum
Juz. &
Bukasov,
S. juzepczukii
Buk.,
S. phureja
Juz. &
Bukasov,
S. stenotomum
Juz. & Bukasov, and
S. tuberosum
L., with subspecies within
S. phureja
,
S. stenotomum
, and
S. tuberosum
.
More recently, Huaman and Spooner (2002)
extended Dodd's classification and classified all
cultivated potatoes within the single species
2.2
Classification of the
Cultivated Potato
The cultivated potato originated somewhere
from central Peru to central Bolivia (Hawkes,
1990), possibly near Lake Titicaca, on the bor-
der of Peru and Bolivia. In its center of origin,
thousands of landraces were grown before the
arrival of the Spanish conquistadores. The intro-
duction of South American material into Europe
led to the adaptation of this material to long-day
circumstances, and was accompanied with a
number of morphological changes in their leaves,
stolons, and tubers. After the late blight epidemic
in Europe in the 1840s, new introductions took
place, but the nature and place of origin of this
material was debated. Plant breeding activities
