In propagating by seed, as in reproducing by buds, we select a portion
of the parent plant--for a seed is surely a part of the parent
plant--and place it in the ground. There is, however, one great
difference between a seed and a bud. The bud is really a piece of the
parent plant, but a piece of _one_ plant only, while a seed comes from
the parts of two plants.
You will understand this fully if you read carefully Sections XIV-XVI.
Since the seed is made of two plants, the plant that springs from a seed
is much more likely to differ from its mother plant, that is, from the
plant that produces the seed, than is a plant produced merely by buds.
In some cases plants "come true to seed" very accurately. In others they
vary greatly. For example, when we plant the seed of wheat, turnips,
rye, onions, tomatoes, tobacco, or cotton, we get plants that are in
most respects like the parent plant. On the other hand the seed of a
Crawford peach or a Baldwin apple or a Bartlett pear will not produce
plants like its parent, but will rather resemble its wild forefathers.
These seedlings, thus taking after their ancestors, are always far
inferior to our present cultivated forms. In such cases seeding is not
practicable, and we must resort to bud propagation of one sort or
While in a few plants like those just mentioned the seed does not "come
true," most plants, for example, cotton, tobacco, and others, do "come
true." When we plant King cotton we may expect to raise King cotton.
There will be, however, as every one knows, some or even considerable
variation in the field. Some plants, even in exactly the same soil, will
be better than the average, and some will be poorer. Now we see this
variation in the plants of our field, and we believe that the plant will
be in the main like its parent. What should we learn from this? Surely
that if we wish to produce sturdy, healthy, productive plants we must go
into our fields and _pick out just such plants to secure seed from as we
wish to produce another year_. If we wait until the seed is separated
from the plant that produced it before we select our cotton seed, we
shall be planting seed from poor as well as from good plants, and must
be content with a crop of just such stock as we have planted. By
selecting seed from the most productive plants _in the field_ and by
repeating the selection each year, you can continually improve the breed
of the plant you are raising. In selecting seed for cotton you may
follow the plan suggested below for wheat.
The difference that you see between the wild and the cultivated
chrysanthemums and between the samples of asparagus shown in Figs. 49
and 50 was brought about by just such continuous seed-selection from the
kind of plant wanted.
By the careful selection of seed from the longest flax plants the
increase in length shown in the accompanying figure was gained. The
selection of seed from those plants bearing the most seed, regardless of
the height of the plant, has produced flax like that to the right in the
illustration. These two kinds of flax are from the same parent stock,
but slight differences have been emphasized by continued seed-selection,
until we now have really two varieties of flax, one a heavy seed-bearer,
the other producing a long fiber.
You can in a similar way improve your cotton or any other seed crop.
Sugar beets have been made by seed-selection to produce about double the
percentage of sugar that they did a few years ago. Preparing and
tilling land costs too much in money and work to allow the land to be
planted with poor seed. When you are trying by seed-selection to
increase the yield of cotton, there are two principles that should be
borne in mind: first, seed should be chosen only from plants that bear
many well-filled bolls of long-staple cotton; second, seed should be
taken from no plant that does not by its healthy condition show
hardihood in resisting disease and drouth.
The plan of choosing seeds from selected plants may be applied to wheat;
but it would of course be too time-consuming to select enough single
wheat plants to furnish all of the seed wheat for the next year. In this
case adopt the following plan: In Fig. 52 let _A_ represent the total
size of your wheat field and let _B_ represent a plat large enough to
furnish seed for the whole field. At harvest-time go into section _A_
and select the best plants you can find. Pick the heads of these and
thresh them by hand. The seed so obtained must be carefully saved for
your next sowing.
In the fall sow these selected seeds in area _B_. This area should
produce the best wheat. At the next harvest cull not from the whole
field but from the finest plants of plat _B_, and again save these as
seed for plat _B_. Use the unculled seed from plat _B_ to sow your crop.
By following this plan continuously you will every year have seed from
several generations of choice plants, and each year you will improve
It is of course advisable to move your seed plat _B_ every year or two.
For the new plat select land that has recently been planted in legumes.
Always give this plat unwearying care.
In the selection of plants from which to get seed, you must know what
kind of plants are really the best seed plants. First, _you must not
regard single heads or grains, but must select seed from the most
perfect plant_, looking at the plant as a whole and not at any single
part of it. A first consideration is yield. Select the plants that yield
best and are at the same time resistant to drouth, resistant to rust and
to winter, early to ripen, plump of grain, and nonshattering. What a
fine thing it would be to find even one plant free from rust in the
midst of a rusted field! It would mean a _rust-resistant plant_. Its
offspring also would probably be rust-resistant. If you should ever find
such a plant, be sure to save its seed and plant it in a plat by itself.
The next year again save seed from those plants least rusted. Possibly
you can develop a rust-proof race of wheat! Keep your eyes open.
In England the average yield of wheat is thirty bushels an acre, in the
United States it is less than fifteen bushels! In some states the yield
is even less than nine bushels an acre. Let us select our seed with
care, as the English people do, and then we can increase our yield. By
careful seed-selection a plant-breeder in Minnesota increased the yield
of his wheat by one fourth. Think what it would mean if twenty-five per
cent were added to the world's supply of wheat at comparatively no cost;
that is, at the mere cost of careful seed-selection. This would mean an
addition to the world's income of about $500,000,000 each year. The
United States would get about one fifth of this profit.
It often happens that a single plant in a crop of corn, cotton, or wheat
will be far superior to all others in the field. Such a plant deserves
special care. Do not use it merely as a seed plant, but carefully plant
its seeds apart and tend carefully. The following season select the best
of its offspring as favorites again. Repeat this selection and culture
for several years until you fix the variety. This is the way new
varieties are originated from plants propagated by seed.
In 1862 Mr. Abraham Fultz of Pennsylvania, while passing through a field
of bearded wheat, found three heads of beardless, or bald, wheat. These
he sowed by themselves that year, and as they turned out specially
productive he continued to sow this new variety. Soon he had enough seed
to distribute over the country. It became known as the Fultz wheat and
is to-day one of the best varieties in the United States and in a number
of foreign countries. Think how many bushels of wheat have been added to
the world's annual supply by a few moments of intelligent observation
and action on the part of this one man! He saw his opportunity and used
it. How many similar opportunities do you think are lost? How much does
your state or country lose thereby?
Select one hundred seeds from a good, and one hundred from a poor,
plant of the same variety. Sow them in two plats far enough apart
to avoid cross-pollination, yet try to have soil conditions about
the same. Give each the same care and compare the yield. Try this
with corn, cotton, and wheat. Select seeds from the best plant in
your good plat and from the poorest in your poor plat and repeat
the experiment. This will require but a few feet of ground, and the
good plat will pay for itself in yield, while the poor plat will
more than pay in the lesson that it will teach you.
Write to the Department of Agriculture, Washington, D.C., and to
your state experiment station for bulletins concerning
seed-selection and methods of plant-improvement.
Next: Selecting Seed Corn
Previous: Propagation By Buds