numbers of plants with more or less of the desired qualities; from the best of these, he may again choose; and so on until the race becomes greatly improved (Figs. 5, 6, 7). This process of continuously choosing the most suitable plants is known as selection. A somewhat similar process proceeds in wild nature, and it is then known as natural selection.
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Fig. 6.—Flax Breeding.
A is a plant grown for seed production; B, for fiber production. Why?
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Fig. 7.—Breeding.
A, effect from breeding from smallest grains (after four years), average head; B, result from breeding from the plumpest and heaviest grains (after four years), average head.
Suggestions.—6.
Every pupil
should undertake
at least
one simple experiment
in selection
of seed. He may select kernels from the
best plant of corn in the field, and also from the
poorest plant,—having reference not so much to
mere incidental size and vigor of the plants that
may be due to accidental conditions in the field,
as to the apparently constitutional strength and
size, number of ears, size of ears, perfectness of
ears and kernels, habit of the plant as to suckering,
and the like. The seeds may be saved and
sown the next year. Every crop can no doubt
be very greatly improved by a careful process
of selection extending over a series of years.
Crops are increased in yield or efficiency in three
ways: better general care; enriching the land
in which they grow; attention to breeding.
