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Articles 1351 - 1380 of 1385

Full-Text Articles in Agriculture

Vegetative Composition And Grazing Capacity Of A Typical Area Of Nebraska Sandhill Range Land, A. L. Frolik, W. O. Shepherd Mar 1940

Vegetative Composition And Grazing Capacity Of A Typical Area Of Nebraska Sandhill Range Land, A. L. Frolik, W. O. Shepherd

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The sandhill area of Nebraska occupies approximately 20,000 square miles of the central portion of the state. Being unadapted to cultivation, the land is for the most part still covered with native vegetation. It is utilized primarily for the production of livestock, chiefly cattle. During the period 1931 to 1938 the sandhills carried annually an average of 1,041,000 cattle, which amounted to 31 per cent of the total number in the state. The management practices used in the Nebraska sandhills have gained national recognition as a good example of range conservation in the United States. The purpose of this study …


The Genetics Congress, R. A. Emerson Jan 1940

The Genetics Congress, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Mice and men reported from

Edinburgh after the Congress

(JOURNAL OF HEREDITY for

September 1939) but since then there

has been silence, as far as getting into the

record any details of the Congress. On

account of the disruption to trans-Atlantic

travel caused by the declaration of

war between England and Germany,

September 3, the American delegation to

the Congress was considerably delayed

in getting back. Only two failed ultimately

to return, Dr. and Mrs. F. W.

Tinney of the Division of Farm Crops

of the University of Wisconsin. They

were among about a dozen members of

the Congress who …


A Zygotic Lethal In Chromosome 1 Of Maize And Its Linkage With Neighboring Genes, R. A. Emerson Jan 1939

A Zygotic Lethal In Chromosome 1 Of Maize And Its Linkage With Neighboring Genes, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

A Bolivian maize

maize with mosaic red pericarp and cob, here designated by the symbol M-M, crossed with a local inbred strain of maize having white pericarp and cob, W-W, produced in F1 21 M-M and 28

W-W plants, not far from the I : I relation expected on the assumption that

the M-M parent was heterozygous for pericarp and cob color, M-M/W-W.

In F2 and segregating F3 cultures, however, there were 130 M-M and 64

W-W plants obviously a 2 : I instead of the 3 : I relation expected. Later cultures

increased these records to …


Wound Healing In Potatoes (Triumph Variety) As Influenced By Type Of Injury, Nature Of Initial Exposure, And Storage Conditions, H. O. Werner Jul 1938

Wound Healing In Potatoes (Triumph Variety) As Influenced By Type Of Injury, Nature Of Initial Exposure, And Storage Conditions, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Tubers of the Triumph variety of potatoes, the one most extensively grown in western Nebraska, are more susceptible than those of other varieties to the various types of injury that occur at harvest time. This greater susceptibility is chiefly the result of long stolons, unusual tenderness of skin, and ease with which the tubers crack. The two latter characteristics have been accentuated by the custom of late planting adopted generally throughout the region in recent years. Many of the difficulties could be avoided by growing another variety. However, as there now seems to be no other variety as well adapted …


Manual Of The Grasses Of The United States, A. S. Hitchcock Jan 1935

Manual Of The Grasses Of The United States, A. S. Hitchcock

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Introduction 1

Uses of grasses 1

Distribution of grasses 5

Morphology of grasses 6

Classification of grasses 10

Nomenclature 12

Common names 14

Scope of the manual 14

Gramineae (Poaceae), the grass family 15

Descriptions of the subfamilies and keys to the tribes 16

Subfamily 1. Festucoideae 16

Subfamily 2. Panicoideae 17

Descriptions of the tribes and keys to the genera 17

Tribe 1. Bambuseae 17

Tribe 2. Festuceae 17

Tribe 3. Hordeae 20

Tribe 4. Aveneae 21

Tribe 5. Agrostideae 22

Tribe 6. Zovsieae 24

Tribe 7. Chlorideae 24

Tribe 8. Phalarideae. 25

Tribe 9. Oryzeae 25

Tribe 10. …


The Effect Of A Controlled Nitrogen Supply With Different Temperatures And Photoperiods Upon The Development Of The Potato Plant, H. O. Werner Sep 1934

The Effect Of A Controlled Nitrogen Supply With Different Temperatures And Photoperiods Upon The Development Of The Potato Plant, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The potato (Solanum tuberosum Linn.) is grown under a great variety of conditions with regard to temperature, length of day, intensity and character of light, texture, fertility, and moisture of soil, and atmospheric humidity. There is need for a better understanding concerning the internal response of the potato plant to these external conditions when they are applied, either singly or in combination with each other, and the resulting morphological response, especially with regard to the tuberization process. It has been the object of this investigation to determine the relation of the nitrogen supply to the processes of stolon and …


Relation Of The Differential Fertilization Genes, Ga Ga, To Certain Other Genes Of The Su-Tu Linkage Group Of Maize, R. A. Emerson Jan 1934

Relation Of The Differential Fertilization Genes, Ga Ga, To Certain Other Genes Of The Su-Tu Linkage Group Of Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

The Ga, or “gamete” gene of maize can be studied only or principally by its disturbance of normal Mendelian ratios of contrasted characters differentiated by genes linked with it. The amount of this disturbance can be used as a measure of the intensity of linkage between Ga and other genes of the su-Tu group.

Disturbance of the 3:1 ratio of starchy, Su, to sugary, su, endosperm has been most studied. In one of the early papers on Mendelian inheritance, Correns (1902) reported that, although crosses between most starchy and sugary varieties gave an F2 ratio of …


The Identification Of The More Important Prairie Hay Grasses Of Nebraska By Their Vegetative Characters, F. D. Keim, G. W. Beadle, A. L. Frolik Dec 1932

The Identification Of The More Important Prairie Hay Grasses Of Nebraska By Their Vegetative Characters, F. D. Keim, G. W. Beadle, A. L. Frolik

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is convenient and sometimes necessary to identify the grasses in their vegetative stage of growth. This is especially desirable in a study of the vegetation of native hay meadows and permanent pastures. This key is prepared as a guide in the identification of the more important prairie hay grasses of Nebraska. The meadows are often harvested before the floral parts of many of the grasses appear. If it is desired, therefore, to study the botanical composition of the native meadows, it becomes necessary to rely on identification of many of the grasses by means of vegetative characters.


The A Series Of Allelomorphs In Relation To Pigmentation In Maize, R. A. Emerson, E. G. Anderson Jan 1932

The A Series Of Allelomorphs In Relation To Pigmentation In Maize, R. A. Emerson, E. G. Anderson

Department of Agronomy and Horticulture: Faculty Publications

Introduction ... 503

The allelomorph Ab ... 504

The allelomorph ap ... 505

Dominance ... 508

Summary ... 508

Literature Cited ... 509


The Frequency Of Somatic Mutation In Variegated Pericarp Of Maize, R. A. Emerson Jan 1929

The Frequency Of Somatic Mutation In Variegated Pericarp Of Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Some years ago (Emerson 1922) the writer announced that in F2 of

certain crosses of variegated with colorless pericarp in maize the heterozygous

individuals changed to self color more frequently than did the homozygous

individuals of the same cultures. No “explanation” of this phenomenon

was then apparent, but later results, though still far from affording

an adequate solution of the problem, have furnished at least a working

hypothesis. The original unpublished paper, with minor modifications,

is given below, under the heading. “Somatic mutations in heterozygous

and in homozygous variegated pericarp.”


The Immediate Effect Of Gametic Relationship And Of Parental Type Upon The Kernel Weight Of Corn, T. A. Kiesselbach Dec 1926

The Immediate Effect Of Gametic Relationship And Of Parental Type Upon The Kernel Weight Of Corn, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This investigation to determine the relation of the kernel weight of corn to the source of pollen with which it was fertilized has been made to answer several questions of both practical and technical interest: (1) To what extent is kernel weight affected in the current crop by the "breadth of breeding" or the gametic relationship? (2) What is the relation of the diversity of parental type to the immediate effect of foreign pollen upon the kernel weight of corn? (3) Is the immediate effect of cross-fertilization upon the kernel weight of sufficient importance to justify the annual mixing of …


A Genetic View Of Sex Expression In The Flowering Plants, R. A. Emerson Jan 1924

A Genetic View Of Sex Expression In The Flowering Plants, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

It seems a conservative statement to say that studies

of the past twenty years among animal forms have

tended increasingly to link the phenomena of sex inheritance

with the behavior of chromosomes. To this

result, cytology and genetics have contributed perhaps

almost equally. The number of forms in which

one sex is known to have a morphologically different

chromosome complex from the other sex are many.

That, with respect to the chromosomes, the female of

certain forms produces gametes of a single kind,

whereas the male produces two kinds, and that in

turn an egg fertilized by one kind of …


Control Of Flowering In Teosinte: Short-Day Treatment Brings Early Flowers, R. A. Emerson Jan 1924

Control Of Flowering In Teosinte: Short-Day Treatment Brings Early Flowers, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Attempts to force teosinte into flower in mid-summer, in order to facilitate hybridizing it with maize, have afforded considerable information concerning the flowering time of teosinte under diverse conditions. The possibility that some of this information may be of use to others suggests its publication. The paper is, therefore, to be considered as a help in the technique of teosinte and maize hybridization rather than a contribution ~to the solution of the physiological problems involved.


Size And Structure Of Leaves Of Cereals In Relation To Climate, William Edward Bruner, John E. Weaver Oct 1923

Size And Structure Of Leaves Of Cereals In Relation To Climate, William Edward Bruner, John E. Weaver

University Studies (University of Nebraska) (1888–1984)

Although a very large amount of work has been done on the variation in form, size, and anatomical structure of native plants grown under different conditions, relatively little attention has been given to similar studies of crop plants. As far as we are able to ascertain, no investigations have been made of variation in the leaves of cereal crops grown under widely different, measured environments.

During the past few years (1920-23), in connection with studies on the development and activities of the roots of crop plants (Weaver, Jean, and Crist, 1922), plant production as a measure of environment (Weaver, 1924), …


Pericarp Studies In Maize. I. The Inheritance Of Pericarp Colors, E. G. Anderson, R. A. Emerson Jan 1923

Pericarp Studies In Maize. I. The Inheritance Of Pericarp Colors, E. G. Anderson, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Introduction ... 466

Nomenclature ... 467

Pigments present in colored pericarp ... 467

Factor relations of pericarp colors ... 468

Factor relations of red pericarp, P ... 468

Factor relations of cherry pericarp ... 471

Discussion and Summary ... 474

Literature Cited ... 475


Corn Investigations, T. A. Kiesselbach Jun 1922

Corn Investigations, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of the investigations reported in this bulletin has been primarily to determine some of the underlying principles involved in corn improvement. The work comprises a study of some of the physiological characteristics of the crop together with a comparison of various selection, breeding, and cultural practices in their relation to grain yield.


Genetic Interrelations Of Two Andromonoecious Types Of Maize, Dwarf And Anther Ear, R. A. Emerson, Sterling H. Emerson Jan 1922

Genetic Interrelations Of Two Andromonoecious Types Of Maize, Dwarf And Anther Ear, R. A. Emerson, Sterling H. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Attention was called by Montgomery (1906)to the occasional appearance

of perfect flowers in the staminate inflorescence of maize and similar

cases were reported by Kempton (1913). Montgomery (1911) described

with illustrations a true-breeding type of semi-dwarf dent maize, the ears

of which were perfect-flowered. Perfect-flowered maize was described

and illustrated also by Blaringhem (1908, pp. 180-183). East and

Hayes (1911, pp. 13, 14) noted and illustrated a perfect-flowered sweet

corn. Weatherwax (1916, 1917) showed that typically pistillate

flowers of maize exhibit in microscopic sections the rudiments of stamens

and that staminate flowers show rudiments of pistils.


The Regional Adaptation Of Corn In Nebraska, T. A. Kiesselbach, F. D. Keim Apr 1921

The Regional Adaptation Of Corn In Nebraska, T. A. Kiesselbach, F. D. Keim

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of this investigation was to determine some of the factors involved in the regional adaptation of corn. The procedure has been to make a comparative study of native corn types, known to be locally adapted to various regional areas in Nebraska through long growth there. The work has been confined to the single species group - Zea mays indentata. No one variety of a common source is grown throughout the state, and therefore it has been impossible to keep within a single variety. It would appear that the data should indicate morphological and histological plant characteristics involved …


Heritable Characters Of Maize: Ix. Crinkly Leaf, R. A. Emerson Jan 1921

Heritable Characters Of Maize: Ix. Crinkly Leaf, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

In 1910 a strain of dent corn obtained at the National Corn Exposition held at Omaha was crossed with a strain of flint corn obtained from the Department of Agronomy of the University of Nebraska. The F1 plants of this cross were normal and no abnormalities had been observed in the parent strains. But since the latter had not been subjected to self-pollination, there is no assurance that one or other of them did not have in it the character to be described here. In the F2 generation of this cross there occurred a tpe of plant that …


The Relative Frequency Of Crossing Over In Microspore And In Megaspore Development In Maize, R. A. Emerson, C. B. Hutchison Jan 1921

The Relative Frequency Of Crossing Over In Microspore And In Megaspore Development In Maize, R. A. Emerson, C. B. Hutchison

Department of Agronomy and Horticulture: Faculty Publications

One of the early developments in the study of linkage in Drosophila was the discovery that the phenomenon of crossing over is confined to the female sex (Morgan 1912). The fact that no crossing over occurs in the male Drosophila holds true not only for sex-linked genes but for factors in the autosomes as well and is so well established that it affords a most convenient method of determining to which of the different linkage groups a new factor belongs.

The same phenomenon, but with the sexes reversed, obtains in the silkworm moth. Tanaka (1914, 1915) has found from back-cross …


Freezing Injury Of Seed Corn, T. A. Kiesselbach, J. A. Ratcliff Jun 1920

Freezing Injury Of Seed Corn, T. A. Kiesselbach, J. A. Ratcliff

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The object of the investigations in this bulletin has been to determine the conditions under which freezing injury may occur to seed corn; to indicate, if possible, the vital changes in the embryo resulting in such injury; and to point out ways by which seed corn of strong vitality and satisfactory yielding capacity may be obtained.


Heritable Characters Of Maize Ii.-Pistillate Flowered Maize Plants, R. A. Emerson Jan 1920

Heritable Characters Of Maize Ii.-Pistillate Flowered Maize Plants, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

In the "freak"

class at the Annual

Corn Show held at Lincoln, Nebraska,

in the winter of 1913-14,

there was exhibited a corn tassel

with a heavy setting of seeds. A few

seeds are not infrequently found in the

staminate inflorescence of maize, particularly

in pod com, and tillers of various

corn varieties often end in ears instead

of in tassels or have tassels, the central

spikes of which are ear like. The freak

exhibited at the com show, however,

was a large. much branched affair.

wholly tassel-like in form except for the

fact that it bore a heavy crop …


Genetical Studies Of Variegated Pericarp In Maize, R. A. Emerson Jan 1917

Genetical Studies Of Variegated Pericarp In Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Two years ago there were presented some results of a study of the inheritance of self pattern in the pericarp of maize seeds, occurring as a sporophytic2 variation in variegated ears (EMERSON1 914). Further results, in entire accord with those previously reported, have now been obtained. In addition, data bearing upon new phases of the problem are also available.

The chief results reported in the earlier paper were the following: ( I ) The more nearly self-colored the pericarp of any seed of a variegated ear, the more likely is the progeny of that seed to produce a self-colored ear …


Transpiration As A Factor In Crop Production, T. A. Kiesselbach Jun 1916

Transpiration As A Factor In Crop Production, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The object of experiments reported in this bulletin has been to determine principles according to which water is used by crops. In many agricultural districts, water is frequently a seriously limiting factor in crop production. It has been thought that some means might be devised through a correct understanding of the principles involved, whereby economy in the use of water in farm practice could be increased. In this effort there are two chief points of attack, namely, (1) adjusting the external factors to the needs of the plant, and (2) selecting plants adapted to the conditions.


A Genetic Study Of Plant Height In Phaseolus Vulgaris, R. A. Emerson Mar 1916

A Genetic Study Of Plant Height In Phaseolus Vulgaris, R. A. Emerson

Nebraska Agricultural Experiment Station: Historical Research Bulletins

When pole and bush beans are crossed, 3:1 segregation results whether the pole bean is very tall or only medium in height and whether the bush bean is very short or relatively tall. To determine the interrelation of these two types of behavior by an analysis of the factors concerned in height of plants in beans and by a study of their mode of inheritance was the object of the investigations reported here.


The Inheritance Of A Recurring Somatic Variation In Variegated Ears Of Maize, R. A. Emerson Jan 1914

The Inheritance Of A Recurring Somatic Variation In Variegated Ears Of Maize, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

The inheritance of variegation has special interest and importance in genetics. It is with forms of variegation that the only two certainly known cases of non-Mendelian inheritance have had to do. I refer to Baur's experiments with Pelargonium, in which crosses of green-leaved and white-leaved forms exhibited somatic segregations in F1 that bred true in later generations, and to Correns 's work with Mirabilis, which showed green and white leaf color, to be inherited through the mother only. De Vries's con- ception of "ever-sporting" varieties was apparently founded largely upon the behavior of variegated flowers in pedigree …


Multiple Factors Vs. "Golden Mean" In Size Inheritance, R. A. Emerson Jan 1914

Multiple Factors Vs. "Golden Mean" In Size Inheritance, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

Groth's preliminary note on the "golden mean" in the inheritance of sizes in SCIENCE of April 17, 1914, pp. 581-584, deserves the attention of geneticists. Its publication is of such recent date that I need only call attention to one or two points that seem to me of particular moment.

In brief, Groth's hypothesis is that the mode

of inheritance in Fl not only of surfaces and

volumes, but also of linear dimensions is to be

expressed by √ab rather than by a + b /2

where a and b are parent sizes. The hypothesis

is based upon …


Shorter Articles And Discussion Simplified Mendelian Formulae, R. A. Emerson Jan 1913

Shorter Articles And Discussion Simplified Mendelian Formulae, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

I was somewhat surprised by 'Morgan's and Castle's suggestions for a simplification of Mendelian formulae. My surprise was not occasioned so much by the forms these suggestions took as by the fact that any pronounced changes were deemed necessary. I had not only employed the usual formula in my own work but had found no difficulty worth mentioning in understanding the formula used by most other workers in Mendelian fields. My experience with students in elementary courses in genetics had not prepared me for the idea that such formula were particularly difficult. Nevertheless I believe in simplifying the formulae if …


The Possible Origin Of Mutations In Somatic Cells, R. A. Emerson Jan 1913

The Possible Origin Of Mutations In Somatic Cells, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

That mutations are accompanied by some change in the germ-plasm is, I take it, indisputable. Have we, however, any reason to suppose that the change takes place within the germ cells? I am not sure, as a matter of fact, that genetists in general regard the gametes as the place of origin of mutations. It is true, however, that experiments in the artificial production of mutations in plants have been limited largely to treatments of the ovaries from about the time of the reduction division to about the time of fertilization. This suggests a belief on the part of investigators …


Shorter Articles And Reports: The Simultaneous Modification Of Distinct Mendelian Factors, R. A. Emerson Jan 1913

Shorter Articles And Reports: The Simultaneous Modification Of Distinct Mendelian Factors, R. A. Emerson

Department of Agronomy and Horticulture: Faculty Publications

In another paper on the inheritance of a recurring somatic variation in variegated ears of maize, it was shown that the amount of red color developed in the pericarp of variegated seeds bears a definite relation to the development of color in the progeny of such seeds. The relation is such that the more color there is in the pericarp of the seeds planted the more likely are they to produce plants with wholly self-red ears and correspondingly the less likely to produce plants with variegated ears. Self-red ears thus produced behave just as if they were hybrids between self-red …