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Chapter 1. A Half Century of Wheat Improvement in the United States

Chapter 1. A Half Century of Wheat Improvement in the United States

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. C. SALMON. 0. R . MATHEWS.



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. W . LEUKEL



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I V The Role of Improved Varieties

1 Improved Varieties of Hard Red Spring Wheat

a Are the Improved Varieties Superior to the Old4

2 Improved Varieties of Durum Wheat

a Relative Yields

3 Improvement of Varieties for the Hard Red Winter Area

a Factors Affecting Choice of Varieties

b Early Varietal Improvement

c Principal Achievements

4 Improvement of Varieties for the Western United States

a Varieties for the Pacific Northwest

b Varieties in California

c Varieties in the Intermountain Areas

d Quality of Western Wheats

5 Improvement of Varieties for the Eastern United States

a Early Improvement in Varieties

b Recent Achievements

c Relative Yields and Increased Production

d Quality

6 Recapitulation

7 Varieties for the Future

V. Improvements in Methods of Breeding Wheat

1 Early Methods of Breeding

2 Objectives in Breeding

3 Resistance to Disease, Insect, and Weather Hazards

4 Testing for Comparative Yields

5 Techniques for Measuring Quality

a Milling Quality

b Quality for Bread

c Pastry Quality . . . . . . . . . . . . .

d Bread-Baking Tests for Soft Wheat

e Macaroni Quality

f Ancillary Quality Tests

VI Control of Diseases

1 Stem Rust

a History and Distribution

b Development of Resistant Varieties . . . . . .

c Discovery of Physiologic Races

d Barberry Eradication

2 Leaf Rust

3 Control of Rusts by Dusting

4 Stripe Rust

5 The Smuts of Wheat

a Bunt or Stinking Smut

b Loose Smut

c m a g smut

6 Wheat Mildew

7 Miscellaneous Diseases

a.Scab



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HALF CENTURY OF WHEAT IMPROVEMENT IN UNITED STATES



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b. Anthracnose

c. Wheat Mosaics

d. Crown, Foot, and Root Rots



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VII. Control of Insect Pests of Wheat . . . . . . . . .

1. Hessian Fly . . . . . . . . . . . . . . .

2. Grasshoppers . . . . . . . . . . . . . . .

3. Wheat-Stem Sawfly . . . . . . . . . . . .

4. Other Insect Pests of Wheat . . . . . . . . .



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Acknowledgments . . . . . . . . . . . . . . . .

References . . . . . . . . . . . . . . . . . . .



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I. INTRODUCTION

A little over fifty years ago Sir William Crookes (1899), President

of the British Association for the Advancement of Science, created a

mild sensation in the United States and startled his own countrymen by

warning them of the “deadly peril of not ha-ving enough to eat because

wheat production could not keep pace with the increase in population.”

“It is almost certain, ” he said, ( ( t h a t within a generation the ever-increasing population of the United States will consume all the wheat

grown within its borders and will be driven to import, and like ourselves,

will scramble for a lion’s share of the wheat crop of the world. The

details of the impending catastrophe no one can predict, but its general

direction is obvious enough.” The president of the British Association

was not a n alarmist and many authorities agreed with him. One in particular, John Hyde, chief statistician for the United States Department

of Agriculture, stated (1899) among other things that “for general agricultural purposes the public domain is practically exhausted and that

consequently there can be no further considerable additions to the faxm

area of this country is too well established to be the subject of controversy. ”

Allowing nearly a generation for error in timing, it is now clear that

these warnings were at least premature, for the United States instead of

importing wheat has supplied its own normal needs and produced a large

surplus for animal feed, alcohol, and food for her allies, and conquered

countries during and after the most devastating war known to mankind.

Neither Crookes nor Hyde saw, nor could they have been expected to

have anticipated, the tremendous effect tha.t research has had on the

capacity of the United States to produce wheat. This is common knowledge today but the details are not well known. Some account of them

should be of general interest and also of some value should there be, as

some believe, a continuing need for all the United States can produce.



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S. C. SALMON, 0. R. YATIIEWS, AND R. W. LEUKEL



11. ACREAQE,

YIELDPER ACRE,AND PRODUCTION

IN THE UNITED

SFATES

1. Production Trends



In the five years ending in 1898 the United States produced 596,000,000 bushels of wheat as compared with 1,200,000,000 bushels for the five

years ending with 1948, an increase of 604,000,000bushels or slightly

more than 100 per cent. The increase is due both to more acres and to

more bushels per acre, as may be seen in Fig, 1, which shows the average

acreage, production, and yield per acre by census years or by ten-year

periods beginning with 1839. These graphs show that in spite of a

marked increase in acreage generally brought about by extension into

more hazardous and less productive areas, the average yield per acre has

not only been maintained but has increased. If the tendency to exaggerate yields per acre in the early days, as noted by Malin (1944),was

generally true, the actual increases are greater than those indicated here.

The harvested acreage and total production have increased almost

constantly since 1839. This increase is due mostly to the westward extension of wheat into new farming areas from the Atlantic Coast into

western Maryland, Pennsylvania, and New York, thence across Ohio,

Indiana, and Illinois into eastern Iowa and southern Minnesota and

reaching the eastern part of the Great Plains about 1900. Wheat production began in the Far West before the middle of the nineteenth century

and rapidly expanded after the discovery of gold in California in 1849.

Ball et al. (1921) have given an interesting account of this westward

march of wheat. Since 1900 (Baker, 1931) much of the expansion has

been into drier and more hazardous areas; this expansion was made possible by technological improvements such as development and use of

farm power and improved machinery, better methods of culture, better

varieties, more effective control of disease, insect, and weed pests, and

by a better knowledge of the relation of the wheat plant to its environment. A significant feature of this development has been a great reduction in the number of man-hours required to produce a bushel of

wheat.

Minnesota, which at one time was one of the leading wheat states,

now grows scarcely one-fourth as much wheat as fifty years ago and

Iowa one-eighth as much. Kansas, on the other hand, grows five times

as much, Nebraska twice as much, and Montana and Texas a thousand

times as much. Oklahoma, which grew practically no wheat before 1895

and less than 1,000,000 acres in any year previous to 1898, produced

an annual average crop in excess of 70,000,000 bushels during the past

ten years. Most of the increase in Kansas, Nebraska, Texas, and Montana is on land that moduced no wheat previous to 1900. Acreages have



HALF CENTURY OF WHEAT IMPROVEMENT IN UNITED STATES



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also increased considerably in North Dakota and in the Pacific Northwest, especially in Idaho and Washington, generally into drier and less

productive areas. The California acreage and production are only about

half what they were before 1900.

The curve of Fig. 1 showing yields per acre is of special interest

because yields per acre are often used to measure or indicate technological improvements. They are reasonably good indices in countries in

which acreage remains fairly constant or where the productivity of the

new acreage does not differ materially from the old. They may be mis-



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FIG.1. Production of wheat in the census years 1839, 1849, 1859, and 1869 and

average acreage, production, and yield per acre by ten-year periods in the United

States from 1870 to 1949.



leading, however, in a country such as the United States, where the

acreage has greatly increased into areas where the conditions for growth

are quite different. If an improvement reduces cost per acre, thereby

permitting a larger expansion on less productive land, average over-all

acre yields may actually be reduced.

The primary objective of the United States farmer has been to grow

more bushels a t a minimum of cost and inconvenience. He takes considerable pride in growing a good crop, but he is vitally concerned with

large yields per acre only to the extent that it contributes to his net income. The profit from wheat relative to that of other crops a1so has a

marked influence. If a new variety or a better cultural method results



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