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Agronomy and Crop Sciences

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Cationic Activities And The Exchange Phenomena Of Plant Roots: Relationship To Practical Problems Of Nutrient Uptake, E. O. Mclean, D. Adams, F. E. Baker Jan 1955

Cationic Activities And The Exchange Phenomena Of Plant Roots: Relationship To Practical Problems Of Nutrient Uptake, E. O. Mclean, D. Adams, F. E. Baker

Journal of the Arkansas Academy of Science

No abstract provided.


Weed Control Investigations On Some Important Aquatic Plants Which Impede Flow Of Western Irrigation Water, United States Department Of The Interior, Bureau Of Reclamation Mar 1954

Weed Control Investigations On Some Important Aquatic Plants Which Impede Flow Of Western Irrigation Water, United States Department Of The Interior, Bureau Of Reclamation

Elusive Documents

During the past 50 years, the acreage of land placed under irrigation in the western United States has increased greatly to meet the growing demand for food and fiber production. To provide this water for crop production it is necessary not only for river waters to be impounded and irrigation canal distribution systems established but also for the irrigation waterways to be free of obstructing plant growths which impede the flow of water. This requires various types of weed control measures in order that originally designed carrying capacities of the waterways may be maintained. Methods involving new techniques developed mostly …


Anther Development In A Male Sterile Line Of Corn, Richard J. Vogl May 1953

Anther Development In A Male Sterile Line Of Corn, Richard J. Vogl

Bachelors’ Theses

Production of viable pollen through growth and differentiation of the anther appears to depend on the interaction of the tapetum and sporogenous tissue. Very little is known about the nature of this interaction. One way to approach this problem is to study the development of the anther in cases where no viable pollen grains are produced. Highly inbred lines of male sterile corn which are completely pollen sterile have been obtained and are available for study.


The Effects Of Thermal-Neutron Irradiation Of Maize And Barley Kernels, John W. Schmidt, E. F. Frolik Jan 1951

The Effects Of Thermal-Neutron Irradiation Of Maize And Barley Kernels, John W. Schmidt, E. F. Frolik

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is the purpose of this paper to report the effects of thermal-neutron irradiation of maize and barley kernels on subsequent germination, plant establishment, and early plant development. Comparisons are made with equivalent neutron treatments of maize pollen, results of which have been reported in part in previous publications.


Progressive Development And Seasonal Variations Of The Corn Crop, T. A. Kiesselbach Dec 1950

Progressive Development And Seasonal Variations Of The Corn Crop, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The chief purpose of these studies has been to determine the normal growth changes that occur in the corn plant at successive intervals when growing in the field, and to observe annual yield variations in relation to prevailing weather conditions. Aside from supplying information regarding the physiology of this crop, the data are of interest to the corn grower because they indicate comparative yields, shelling percentages, moisture contents, and feed constituents at various stages of development. Some data also are presented concerning the effects of frost, drouth, day length, and the economic value of tillers and seminal roots.


The Influence Of Crop Plants On Those Which Follow V, Theodore Eugene Odland, Robert Smith Bell, John B. Smith Aug 1950

The Influence Of Crop Plants On Those Which Follow V, Theodore Eugene Odland, Robert Smith Bell, John B. Smith

Special Collections (Miscellaneous)

This is a study of the effect which crop plants have on the growth and yields of those crops which follow. The study began in 1907; this bulletin reports the results from 1930 to 1942. Millet, mangels and rutabagas generally seem to be harmful to crops which follow them. Carrots, mangels and millet were least favorable of all crops to mangels. Potatoes did poorest when following potatoes, rutabagas, or millet. Rutabagas yielded low following rutabagas, mangels and millet. Onions were unfavorably affect by preceding crops of mangels, cabbage, or rutabagas. There is no simple explanation for the effect of crops …


Microorganisms And Soil Structure, T. M. Mccalla Mar 1950

Microorganisms And Soil Structure, T. M. Mccalla

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Laboratory tests were made to determine the effectiveness of different compounds and microbial groups in increasing the stability of Peorian loess lumps against the action of falling water drops. The influence of these on percolation tests in the laboratory was also determined.

Many organic substances-dextrose, sucrose, starch, peptone, cullulose, and gum arabic-did not themselves contribute directly to soil-structure stability, though these substances do furnish energy material for soil microorganisms, which can convert them readily into either microbial tissue or decomposition products that increase soil-structure stability. Lignin, proteins, oils, fats, waxes, resin, and paraffin increased the stability of lumps of …


Pollination Cycles And Pollen Dispersal In Relation To Grass Improvement, Melvin D. Jones, L. C. Newell Oct 1946

Pollination Cycles And Pollen Dispersal In Relation To Grass Improvement, Melvin D. Jones, L. C. Newell

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The plant breeder is initially concerned with gaining a knowledge of the breeding behavior of his plant materials in order that improvement may be undertaken effectively. It is important to know the different characteristic pollination habits of these plants. To develop and apply techniques applicable to the improvement of a given grass crop, it is desirable to know the time of day and the number of days that the grass sheds pollen. The effects of temperature, humidity, light, and wind on pollination must be considered. Once superiority of germplasm is obtained, the most important consideration is the maintenance of this …


Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel Aug 1943

Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of this bulletin is to present the data on nitrate contents and nitrate production in tests where straw or stalk residues were left on the surface through subsurface tillage, as compared with check treatments where these residues were plowed under or were absent. Nine of these tests were at Lincoln, Nebraska, and one was at the Hastings, Nebraska, Hydrological Project. Two tests were conducted in 1939, four in 1941, and four in 1942.


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 …


A Proposed Method For Classifying And Evaluating Soils On The Basis Of Productivity And Use Suitabilities, Arthur Anderson, A. P. Nelson, F. A. Hayes, I. D. Wood May 1938

A Proposed Method For Classifying And Evaluating Soils On The Basis Of Productivity And Use Suitabilities, Arthur Anderson, A. P. Nelson, F. A. Hayes, I. D. Wood

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is the object of this paper to present a method for classifying and evaluating the soils as mapped in regular soil surveys on the basis of land types, which are here defined as areas having reasonably similar productivity and use suitabilities. The standards used to differentiate land types will vary according to the desired objectives, but any material difference in yield, or in practices necessary to maintain a desirable level of productivity will justify recognition of land types. The proposed procedure involves a more detailed study of the influence which soils, slope, erosion, and drainage have on specific crops …


The Effects Of X-Rays Upon The Roots Of Zea Mays, Bernard Louis Wolfe Jun 1937

The Effects Of X-Rays Upon The Roots Of Zea Mays, Bernard Louis Wolfe

Bachelors’ Theses

Since. the discovery of X-rays by Rontgen in 1895, the majority of published papers dealing with the influence of these rays on plant life have considered their general effects on physiological processes including rate of seed germination and growth, respiration, and movements. A large number of investigators have worked on the morphological and cytological aspects while comparatively few workers have been interested in the histological effects of the stimulated tissues. The purpose of this thesis is to show the histological, morphological, and cytological effects of X-rays upon the root tips or the Zea Mays as well as the effects these …


Water Relations To Germination Of Zea Mays, Mary Hood Aug 1936

Water Relations To Germination Of Zea Mays, Mary Hood

Masters Theses & Specialist Projects

Four experiments regarding water relations to germination of zea mays.

  1. Per cent of water absorbed by seeds of zea mays with supply of water controlled and filter paper used as water absorbent.
  2. Per cent of water absorbed by seeds of zea mays with supply of water controlled and filter paper used as water absorbent.
  3. Per cent of water absorbed by seeds of zea mays with supply of water controlled and cotton used as water absorbent.
  4. Per cent of water absorbed by seeds of zea mays with supply of water controlled and cotton used as water absorbent.


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 …


Inheritance Of Resistance To Loose Smut (U. Tritici) In Certain Wheat Crosses, Bion Tolman May 1933

Inheritance Of Resistance To Loose Smut (U. Tritici) In Certain Wheat Crosses, Bion Tolman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During recent years the principles of Mendelism have been used extensively in the production of the new types of plants possessing resistance to various diseases. Results of this mode of attacking the disease problem have been very favorable. Old varieties are gradually giving way to newer types equal to or exceeding in quality and productivity as well as possessing resistance to one or more diseases.

Loose smut (U. tritici) in wheat, while not as serious a problem in Utah as the covered smut (T. tritici), according to Tapke (14) has caused an average annual loss of between 50,000 and 100,000 …


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.”


A Study Of The Seasonal History Of Alfalfa Flowers As Related To Seed Production, John W. Carlson May 1927

A Study Of The Seasonal History Of Alfalfa Flowers As Related To Seed Production, John W. Carlson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A few researches have been concerned with the structure and pollination of alfalfa flowers. Others have considered the biological problems concerned in the pollination and fecundation of the flowers. In none of these studies, however, has an attempt been made to follow carefully the alfalfa flowers through various stages of development. Nor has any effort been made to determine what effect the condition and duration of these stages may have upon the resulting seed crop.

The work that follows is a study of the changes through which the alfalfa flowers pass during the season while functioning as organs of seed …


The Differential Reaction Of Strains Within A Variety Of Wheat To Physiologic Forms Of Puccinia Graminis Tritici, T. A. Kiesselbach, George L. Peltier Dec 1926

The Differential Reaction Of Strains Within A Variety Of Wheat To Physiologic Forms Of Puccinia Graminis Tritici, T. A. Kiesselbach, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Black stem rust of wheat (Puccinia graminis tritici (Pers.) Erikss. & Henn.), which occurs in Nebraska and thruout most of the wheat producing regions of the world, is of a composite nature, in that it consists of a number of physiologic forms which can be determined by their action on different varieties of Triticum species, as shown by Stakman and Levine. The ordinary commercial variety of wheat may likewise be regarded as a mixture, in that it consists of numerous strains, which differ in some more or less important characteristics, as has been frequently indicated in the literature concerning …


Field Studies Of The Control Of The Sugar Beet Nematode. (1920-24). (Heterodera Schachtii Schmidt)., Alfred H. Bateman May 1924

Field Studies Of The Control Of The Sugar Beet Nematode. (1920-24). (Heterodera Schachtii Schmidt)., Alfred H. Bateman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The dire consequences of nematode invasion have been graphically depicted by Spiegler (1907), who says, the beet industry was at its heyday during the seventies. Nor satisfied with the land already in cultivation, the farmer plowed fertile lands along the border of the streams, wherein to grow beets, obtaining in some cases of 20 to 27 tons an acre.


Bulletin 119 - Take-All Of Wheat And Similar Diseases Of Cereals, W. M. Carne, J. G.C. Campbell Jan 1924

Bulletin 119 - Take-All Of Wheat And Similar Diseases Of Cereals, W. M. Carne, J. G.C. Campbell

Bulletins 1 - 2999

This important disease, known also as Footrot, Blackleg, and Whiteheads, affects wheat principally, but also occurs on barley, rye, and certain grasses. In a very few instances it has been known to attack oats, but this is so rare that oats may be regarded for practical purposes as free from attack. Of the grasses attacked the most important, from a farming point of view in Western Australia, are Bailey Grass (Hordeum murinum), Silver Grass (Festuca bromoides and F. myuros), and the so-called Spear grasses (Bromus spp.). These annual grasses are very common in the wheat belt.


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.


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 …


A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. Ii. Infection Studies With Puccinia Graminis Tritici Form Iii And Form Ix, George L. Peltier Dec 1923

A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. Ii. Infection Studies With Puccinia Graminis Tritici Form Iii And Form Ix, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Stakman and Levine have shown that Puccinia graminis tritici (Pers.) Erikss. and Henn. consists of a number of biologic forms, which can be determined by their action on different varieties of Triticum species. To date 37 such biologic forms have been identified by them through the parasitic action on 12 differential hosts chosen from a large number of varieties of Triticum species. To determine whether these biologic forms remain constant in their behavior under various environmental conditions, a detailed study of the host-parasite relation was undertaken with 2 of these forms. At the same time an opportunity was afforded to …


Improvement Of Small Grains By Pure Line Selection, Dilworth Walker May 1923

Improvement Of Small Grains By Pure Line Selection, Dilworth Walker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present economic status of grain farming in the United States calls for adjustments in various ways. Legislation, such as price fixing, can do very little. Adjustment of acreage along with improved methods of marketing can do much. But improvement of the grains grown through breeding processes to increase the yields per acre and improve the milling quality, will render a service of permanent value, since all of the results appear in the profit column.


Hybridization Of Wheat, Floyd M. Beach May 1923

Hybridization Of Wheat, Floyd M. Beach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper is to set forth the purpose of wheat hybridization. To do this properly it is necessary to know the history of hybridization of plants. Also to know some of the workers in this field and the hybrids produced by them. In the work at the Experiment Stations the various experimenters have discovered many interesting facts which it is necessary to know and understand. To thoroughly comprehend the work it is also necessary to do the actual processes of the work and to carry the hybrid through several generations and eventually to the goal for which …


Bulletin 105 - Pedigree Selection Of Seed At The Chapman And Merredin Experiment Farms, Geo L. Sutton Jan 1923

Bulletin 105 - Pedigree Selection Of Seed At The Chapman And Merredin Experiment Farms, Geo L. Sutton

Bulletins 1 - 2999

A Paper read before the Royal Society of the Royal Society of Western Australia, 12th October,1921.

"Pedigree" or "Pure Line" selection is that system of selection under which the choice is made, not. solely because of the attractive appearance of the plant, but because of its ability to transmit its good qualities to the progeny. Such a system requires, and the method of selection ensures, that the qualities sought after shall be hereditary. For this purpose a record of ancestry is essential, hence the use of the term "pedigree."


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


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.