Hayes and Garber - Cucurbit Breeding

220 BREEDING CROP PLANTS
approached in calyx or corolla characters the conditions found in
S. tuberosum cultivated varieties. Progeny of seed of cultivated
varieties showed Mendelian segregation, but no characters were
obtained which had not been observed in ancient cultivated
varieties. Wittmack (1909), after a careful botanical study of
species, reached the conclusion that S. tuberosum was the stem
species from which all cultivated potatoes arose.
The evidence presented by De Candolle (1886) seems sufficient
to prove that the potato was wild in Chile and in a form which
is very similar to that of our cultivated plants. Heckel (1912)
reports a study of changes under cultivation of Solanum tuberosum
forms collected in the wild in Bolivia and Peru by M. Verne.
The wild plants were 0.25 meter in height, bore blue flowers and
deep green foliage and tubers about the size of a hazel nut each
produced at the end of a long stolon. These tubers were planted
at Marseilles in a garden heavily fertilized with manure. Little
change was observed in flower and fruit characters but there were
pronounced changes in the subterranean parts. The yellowish
tubers, each borne at the end of a much shortened stolon, contained
a much greater amount of starch than wild tubers, while
the characteristic bitter taste of the wild tubers disappeared.
Much more profound changes occurred under cultivation with
tubers of S. maglia (Heckel, 1909).
There seems to be no good reason for speaking of all these
tuber changes as mutations. It seems more in line with modern
genetic usage to consider them as the normal expressions of the
inherited factors under the new conditions of environment
which occur under cultivation.
The cultivated potato was first introduced into Spain and
Portugal by the Spaniards during the first half of the sixteenth
century. 1 Clusius described and illustrated the potato from
plants sent him in 1588 by the governor of Mons. The published
description was made in Clusius' "Rariorum Plantarum Historia"
which appeared in 1601. The original plant obtained by
Clusius bore two tubers and a fruit ball. This variety bore reddish
tubers and light purple flowers. The spread from this introduction
was probably next into Italy and from there early in
the seventeenth century to Austria, then to Germany, from Germany
to Switzerland and then to France.
Drake, after a West India piratical trip, took back the Roanoke
i
EAST, 19086.