Agriculture Commons^™

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 The original unpublished paper, with minor modifications,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.”

Spraying Tree Fruits, C. C. Wiggans, E. H. Hoppert

Nebraska Agricultural Experiment Station: Historical Circulars

The production of sound, clean fruit is unquestionably one of the major problems facing the modern fruit grower. Culture may be neglected and pruning delayed for a time but the omission of sprays for even a single season demonstrates their absolute necessity. This applies equally to the commercial grower and to the farmer or gardener who has only a few trees.

Stem Rust In Nebraska. Part I. General Survey Of Sources. Part Ii. Identification Of The Physiologic Forms Of Puccinia Graminis From Various Sources, George L. Peltier, A. F. Thiel

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Part I: Since the inception of the barberry eradication campaign in 1918 in Nebraska, the question has continually been asked, "Will the eradication of the barberry in the state eliminate or materially reduce stem rust?" In order that an answer might be obtained, an investigation to determine the sources of primary infection of stem rust on cereals was inaugurated in the spring of 1921. Although these studies have been carried on for 6 years, no definite statement regarding the relative importance of the primary sources and the amount of stem rust prevalent in the state from season to season originating …

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 …

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 …

Alfalfa Investigations, T. A. Kiesselbach, Arthur Anderson

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of these alfalfa investigations has been to determine the relation of variety, source of seed, and cultural practice to the yield and quality of hay produced. Due to the high initial cost of seeding, the inconvenience and wastefulness of losing a stand prematurely, and the superiority of properly-made hay, an understanding of these relationships is very important.

Grazing Periods And Forage Production On The National Forests, Arthur W. Sampson, Harry E. Malmsten

Aspen Bibliography

Stockmen in the West have always had confidence in the adequacy of the native forage crop to provide pasturage for their livestock. Indeed, under normal climatic conditions this enormous natural resource has not failed the grazier, except where it has been called upon to meet unreasonable demands. The productivity of the range has declined sharply, however, wherever the requirements of plant growth have been disregarded for many years in succession. Where there has been too early or too frequent and to heavy grazing, undue trampling, or some other unsatisfactory feature of range use, the results have been uniformly bad. Many …

The Spindle-Tuber Disease As A Factor In Seed Potato Production, H. O. Werner

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The lines of experimentation that supplied the data herein reported, stated in very general terms, were as follows: (1) Tuber-line selection studies (2) Relation of environmental conditions to seed-potato production (3) Seed-potato strain trials of certified and uncertified stock (4) Spindle-tuber transmission experiments. Most of these general lines of experimentation will not be completely discussed as a unit in any one part of the bulletin. For the sake of clarity, consecutive thought, and elimination of repetition, data will be selected from any experiment for insertion and discussion under the most logical heading in any part of the bulletin. Unless otherwise …

A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. Iv. Overwintering Of Urediniospores Of Puccinia Graminis Tritici. V. The Period Of Initial Infection Of Urediniospores Of Puccinia Graminis Tritici On Wheat. Vi. Influence Of Light On Infection And Subsequent Development Of Urediniospores Of Puccinia Graminis Tritici On Wheat, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

IV. In order to ascertain whether the urediniospores of Puccinia graminis tritici (Pers.) Erikss. and Henn. overwinter under the environmental conditions prevailing at Lincoln, Nebraska, a series of experiments was carried out extending over a period of 5 years. The results of this investigation are briefly presented. V. By the period of initial infection is meant the time required by a pathogen after it reaches a susceptible plant part to enter the tissues. To determine what the period of initial infection of urediniospores of Puccinia graminis tritici might be, experiments were undertaken during the season of 1923-24 using urediniospores of …

Winter Wheat Investigations, T. A. Kiesselbach

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Twenty years of wheat breeding, consisting chiefly of the isolation and testing of pure lines, has now been conducted at the Nebraska Agricultural Experiment Station. It is the purpose of this paper to report the conduct and results of this work. The resulting strains are compared with the best other wheats available from Nebraska and other sources. The effects of a number of cultural practices related to the preparation of seed, seeding, treatment of the growing crop, and harvesting are also presented. Some consideration is given to the experimental technique of the comparative tests.

A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. Iii. Further Studies Of The Viability Of Urediniospores Of Puccinia Graminis Tritici, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

1. The influence of relative humidity and temperature on the viability of the urediniospores of two Physiologic Forms of Puccinia graminis tritici has been determined. 2. The same general relation between the viability of the urediniospores and the relative humidity and temperature was found, namely, that the lower the temperature the longer the spores retained their viability at all relative humidities, while at any stated temperature the spores were viable the longest at the medium humidities. 3. Urediniospores of Physiologic Form XXI held at 49.0 per cent relative humidity and maintained at a temperature of 5° C. when tested for …

Hardy Alfalfa For Nebraska, T. A. Kiesselbach, A. Anderson

Nebraska Agricultural Experiment Station: Historical Circulars

Comparative tests of varieties and regional strains of common alfalfa at the Nebraska Experiment Station have clearly indicated that winter hardiness is an important factor to be considered when purchasing alfalfa seed. Much of the seed sold in the United States has proved inferior in this regard for Nebraska conditions. The use of southern-grown domestic seed or seed imported from countries with a much milder climate than that of Nebraska should be avoided in this state. On the other hand, reliance may be placed on the seed of hardy varieties or hardy regional strains of common alfalfa grown in Nebraska …

Further Studies On The Effect Of Environment On Potato Degeneration Diseases, R. W. Goss, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The identification of potato degeneration diseases in the field is extremely difficult owing to the number of diseases now described, their manifestation on different varieties, the combination of several diseases on the same plant, and the further splitting up of these combinations into separate diseases. The influence of environmental factors in intensifying or inhibiting the symptoms of these diseases also increases the difficulty of diagnosis. In the present investigation the effect of environmental factors has been studied with the purpose of determining the limiting factor or factors in the masking of the symptoms, in the hopes of simplifying a complex …

Control Equipment For The Study Of The Relation Of Environment To Disease, George L. Peltier, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The investigation of certain plant disease problems in Nebraska has necessitated the study of the relation of various environmental factors to these diseases. The control of these environmental factors in the greenhouse studies has been obtained by the use of previously described apparatus or their modification and adaptation, along with new methods which have been devised to meet the needs of these investigations. In view of the widespread interest in the subject of environmental control for experimental studies, it was deemed advisable to present briefly the methods now in use in this department in the hope that the information may …

Potato Wilt And Stem-End Rot Caused By Fusarium Eumartii, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The present study was undertaken to obtain more information regarding the pathogenicity of Fusarium eumartii and to compare its action with F. oxysporum, in order to distinguish between and to determine the relative importance of the diseases produced by these two organisms. An effort was also made to explain the many negative results of isolation studies reported by various investigators, as well as the inconsistent results often reported in studies of the transmission of wilt by infected tubers. Investigations dealing with the effect of certain environmental conditions on the occurrence of the disease were also undertaken. All of the …

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.

Effect Of Environment On Potato Degeneration Diseases, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

During recent years much of the investigational work on the degeneration diseases of the potato has been directed toward the separation and identification of a number of diseases formerly grouped under the general names of mosaic, leaf roll, and "running out". Extensive studies have also been made on methods of transmission, host range, overwintering and the identification of the evasive causal factor. Investigations of this type, however, have progressed slowly because of the necessity of developing new methods of research, because of the complexity of the problem, and because of the lack of knowledge regarding the causal factors. Meanwhile there …

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

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

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 …

Seed Potato Investigations, H. O. Werner, R. F. Howard

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The objects of the investigations reported in this bulletin were:

• To determine the condition of western Nebraska seed stock by the tuber unit method and by comparative trials in western Nebraska and various other points.
• To determine the effect of culture, place, disease, etc., upon seed value.
• To perfect methods of applying results to seed production in western Nebraska.

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), …

Relation Of Environment And Other Factors To Potato Wilt Caused By Fusarium Oxysporum, R. W. Goss

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The present work was undertaken to determine the influence of some environmental factors on the infection and progress of the disease potato wilt. The work has not progressed to the point of determining the exact relation of each of these factors. However, the results thus far obtained are presented here in order to direct attention to the nature and distribution of the disease in relation to the environmental conditions under which certain types of infection take place.

Bulletin 106 - The Red-Legged Velvet Earth Mite, L. J. Newman

Bulletins 1 - 2999

This pest is sometimes called in error the "Red Spider" or the 'Earth Flea."

It is neither a spider nor a flea, being a species of mite.

It belongs to the family of mites known as the Eupodidae and to the Genus Notophallus. Many of the members of this family are predaceous, that is, they live upon other insects or animals, but the species we are dealing with appears to be wholly a plant feeder. A popular idea is that the mite lives and breeds in the earth. The rapidity with which newly planted vegetables become infested gives good excuse …

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

A Study Of The Environmental Conditions Influencing The Development Of Stem Rust In The Absence Of An Alternate Host. I. The Viability Of The Urediniospores Of Puccinia Graminis Tritici Form Iii, George L. Peltier

Nebraska Agricultural Experiment Station: Historical Research Bulletins

No exact data are at hand regarding the influence of temperature and relative humidity on the viability of the urediniospores of stem rust under controlled conditions. 1. The influence of relative humidity on the viability of the urediniospores of Puccinia graminis tritici Form III is very pronounced and closely associated with temperature. 2. At high relative humidities, depending somewhat on the temperature, the percentage of germination is low and the period over which the spores are viable is very short. 3. The same relation exists at the low relative humidities except that it is not so pronounced and is more …

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

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

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 …

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 …