DETERIORATION IN SOME HORTI- 
CULTURAL VARIETIES THROUGH 
DEFICIENT ARTIFICIAL SELECTION 
H. H. M. BowMan 
Biological Laboratory, Toledo University 
gathered during the summers 
of 1917, 1918 and 1919, and when 
analyzed would seem to indicate that 
these horticultural varieties of several 
decorative plants, chiefly annuals, have 
seriously deteriorated from their type 
standards. An attempt to inquire 
into the causes for this deterioration 
leads one to believe that the fault lies 
with the producers of the seed and 
their failure to maintain careful arti- 
ficial selection in breeding these varie- 
ties. It is assumed that the war and 
the consequent labor conditions are to 
account for the situation. The ob- 
servations here presented may also be 
of use to indicate the more labile char- 
acters in these particular varieties and 
possibly by thus analyzing their heredi- 
tary constitution, material may be se- 
cured in them for genetical studies. 
Te following data have been 
UNIFORM METHODS OF CULTIVATION 
For many years it has been the 
writer’s privilege to cultivate each 
summer at his home in eastern Penn- 
sylvania, a small garden containing 
many varieties of herbaceous and 
shrubby perennials and bulbous plants. 
In the more open borders are usually 
planted the common annuals and bi- 
ennials, such as asters, poppies, zinnias, 
marigolds, balsams, pansies, mignon- 
ette, delphiniums, etc. The seeds for 
these plants have annually been pur- 
chased from the largest and most re- 
liable seedsmen in the East and have 
always produced excellent results. In 
some instances Centaureas, Scabiosa, 
seedling Dahlias and Salpiglossis have 
been exhibited. The soil and ordinary 
cultural methods have been practically 
the same for a long period, and with 
good seed from reliable sources the 
conditions, so far as germination and 
growth are concerned, have been un- 
changed in the successive seasons. 
All these conditions, therefore, being 
so uniform, any extraordinary varia- 
tion in results good over a long period 
preceding would, naturally, not be 
due to the cultivation. The explana- 
tion must be sought in the seeds. 
The same varieties were grown in 
the two summers preceding that of 
1919, and the same deterioration was 
observed in these particular varieties, 
but even in a more marked degree was 
it noticed in the season mentioned. As 
the observations were more carefully 
taken this past summer, only the data 
for that period are here set forth. In 
the spring of 1919 seeds were purchased 
of named varieties of the China Aster, 
Callistephus chinensis, Zinnia elegans; 
Tagetes erecta, the African marigold; 
Matthiola incana and the corn-flower, 
Centaurea cyanus, together with seeds 
of other decorative plants and garden 
vegetables. These named varieties had 
been bought of the same firm in the pre- 
ceding years and were planted under 
similar conditions in the same garden, 
and all germinated with excellent per- 
centages. 
Before proceeding in detail with the 
results of the plantings of the genera 
named above, it should be mentioned 
that the crops produced from vegetable 
and other seeds were in the highest 
degree satisfactory and that these seeds 
were evidently up to the standard of 
previous years. The need for propa- 
gating large quantities of food plants 
during the war period obviously was an 
incentive for breeders to maintain as 
high a standard of quality as possible. 
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