Life Sciences Commons^™

Practical Improvements For Pivot And Surface Irrigation, Jonathan A. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Irrigation is critical to meeting global food and fiber demands. Optimizing agricultural irrigation may help sustain production levels, while reducing its demand for water. This research evaluated precision sprinklers and drip irrigation for pivots, five pivot track mitigation tools, three scientific irrigation scheduling (SIS) methods, sensors for surface irrigation cutoff, and automating surface systems to implement surge irrigation. With pivots and surface irrigation being the most common methods for irrigation in the West, small improvements from these tools could result in significant water savings.

Low energy precision application (LEPA) sprinklers and mobile drip irrigation (MDI) were tested on two pivots. …

Seeding Rate, Herbicide, And Irrigation Effects On Spring-Seeded Oat-Alfalfa Companion Crops, Carson D. Roberts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Small grain companion crop seeding rate recommendations for alfalfa (Medicago sativa L.) establishment are dated and inconsistent, and how a small grain companion crop seeding rates should be adjusted at different moisture levels is unknown. A study was conducted to provide clarity about oat (Avena sativa L.) companion crop seeding rates that maximize weed suppression and forage yield and minimize the effect on alfalfa stand establishment. This experiment considered oat companion crop seeding rates at various irrigation levels. Companion crop treatments consisted of oats sown at 89, 45, 22, 10, and 0 (with and without herbicide) kg ha …

Innovative Water Management Using Advanced Irrigation Systems And Biochar, Jonathan A. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two approaches to water optimization in agriculture are to increase soil water retention and improve the efficiency of irrigation. A soil amendment that has received attention for its ability to increase soil water retention is biochar, the remaining biomass after high C materials have been pyrolyzed (burned with limited oxygen and heat). Two studies were conducted at a total of 10 site-years in Utah from 2018 to 2020 to evaluate how wood biochar influences the productivity and crop quality of irrigated alfalfa (Medicago Sativa L.), corn (Zea mays L.), and wheat (Triticum L.), along with soil water tension. One study …

Response Of Glyphosate-Resistant Alfalfa To Glyphosate Application In The Intermountain West, Logan Chet Loveland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Glyphosate-resistant (GR) alfalfa (Medicago sativa L.) has been widely adopted in the Intermountain West United States, where alfalfa plays an important role in agriculture. Exceptional tolerance to glyphosate application has been a reported strength of this technology; however, growers have recently reported potential crop injury under certain environmental conditions. The purpose of this study was to document and characterize the injury, identify local conditions that may have contributed to crop injury, and determine best management practices for avoiding injury to GR alfalfa in the Intermountain West. The effects of glyphosate rate and application timing were investigated at 24 sites …

Yield And Quality Of First-Year Corn Silage Following Alfalfa Stand Termination As Affected By Tillage, Herbicide, And Nitrogen Fertilizer, Jason Daniel Clark

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Glyphosate-containing herbicides such as Roundup® are a common and highly effective method to terminate alfalfa stands. With the development of glyphosate-resistant (Roundup Ready®) alfalfa, this tool is no longer an option. The purpose of this research was to determine the optimal termination methods to use when rotating from glyphosate-resistant alfalfa into silage corn. Studies were conducted in 2012 and 2013 in Cache Junction and Cornish, Utah using five different combinations of tillage type and timing (fall conventional till, spring conventional till, fall strip-till, spring strip-till, and no-till), four 2,4-D plus dicamba herbicide timings (fall, spring, in-crop, and a control), and …

Forage Yield And Quality Of Binary Grass-Legume Mixtures Of Tall Fescue, Orchardgrass, Meadow Brome, Alfalfa, Birdsfoot Trefoil, And Cicer Milkvetch, Steven R. Cox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Managed pasture forms the foundation for much of the U.S. livestock iv production. Increased forage yield and quality can be achieved with nitrogen (N) fertilizer but increases the cost of pasture production. Rising prices of N have led to a return to the use of grass-legume pastures to reduce or replace commercial N fertilizer. There is a need to identify viable grass-legume mixtures and species planting ratios for the region of the Intermountain Western United States The purpose of this study was to identify grass-legume combinations and planting ratios that maximize forage production and forage quality in irrigated pastures. The …

The Effect Of Salinity Level Upon The Yield, Root Growth, And Water Extraction Of Contrasting Rooting Subpopulations Of Alfalfa (Medicago Sativa) Under Conditions Of Zero Leaching, Laura A. Vincent

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A major problem in irrigated agriculture in the Western U.S. is the gradual accumulation of salinity in the plant root zone. These nonuniformly saline soils contain increasing amounts of salinity with depth, and salt accumulation is accelerated in situations where leaching is minimized. Root growth and thus plant yield is limited in these soils due to decreased water uptake. We studied the root growth of two subpopulations of alfalfa differing in their ability to produce fibrous roots to determine if altering root morphology would increase plant yield and water extraction, in an irrigated saline soil.

Soil profiles for a control …

Membrane Protein As A Basis Of Nacl Tolerance In Alfalfa, Husni N. Sabah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study sought to determine whether NaCl altered the plasma membrane proteins in alfalfa exhibiting differential NaCl concentrations, and whether CaSO₄ modified the responses. Two alfalfa cultivars, Centurion and Condor, were grown in 0.5 strength Hoagland solution in a greenhouse. The cultivars were exposed to 0, 88, and 132 mM of NaCl alone and mixed with CaSO₄ ⋅ H₂O at 7 and 14 Mm CaSO₄ for 3, 9, and 60 days.

In experiment 1, roots were dried to determine their Na, Ca, K, and Mg concentration. The results were similar to previous reports in which …

Effect Of Salinity (Nacl) On Germination, Growth, Ion Accumulation, And Protein Synthesis In Alfalfa (Medicago Sativa L.), Thamir S. Al-Niemi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To study the effect of NaCl stress on gene expression in alfalfa (Medicago sativa L.), greenhouse and laboratory experiments were conducted with 22 cultivars during germination and post-germination growth. The ability of alfalfa cultivars to germinate at the different NaCl concentrations was not related to their postgermination performance (salt tolerance) under those conditions.

Genetic effects were evident for Na and Cl ion uptake and accumulation in alfalfa shoots and roots. The strategies of alfalfa cultivars to cope with NaCl stress includes exclusion of Na from shoots and Cl from roots or from the whole plant depending on cultivar and …

Hydrogen Uptake Genes And Nitrogen Fixation Efficiency Of Rhizobium Species In Symbiosis With Alfalfa, Chickpea And Pigeonpea, G. Mustafa Sajid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plasmids pDN211 and pDNll, isolated from the gene bank of the Rhizobium japonicum strain I-110, have been reported to complement two different Nif⁺ Hup^· (nitrogen fixation positive and hydrogen uptake negative) mutants. A 5.9-kb Hindiii DNA fragment of the cosmid pHU52, isolated from the gene bank of R. japonicum strain 122DES, has been reported to code for the two polypeptide subunits of uptake hydrogenase. To determine homology between the structural genes of uptake hydrogenase of the two strains, a Southern blot of the Hindiii restriction fragments of the plasmids pDN211 and pDN11 was hybridized to the 5.9-kb …

Potassium And Sodium Interrelations In Alfalfa Phenotypes Grown On Calcareous Soil, Suresh S. Dhumal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three greenhouse experiments were conducted with three phenotypes of alfalfa (Medicago sativa L.) obtained from a potassium (K)-deficient field and with their diallel crosses grown on low K soil. The first experiment was conducted to study the partitioning and broad-sense heritability of K and sodium (Na) between leaves and stems of the three phenotypes which were deficient in K and exhibited normal (N), marginal chlorotic (M), and white spot chlorotic (W) leaflets. The second experiment was conducted to study the partitioning of K and Na in leaves, stems, and roots as influenced by 32 alfalfa crosses obtained from diallel …

A Simple Model To Predict Optimal Harvest Time Of Alfalfa Using Near Infrared Reflectance Spectroscopy, Environmental, Morphological, And Growth Parameters, Jody A. Gale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Knowledge of relationships between nutrient levels, yield, maturity, and environmental influences on alfalfa (Medicago sativa L.) are necessary to estimate when to harvest alfalfa to maximize quality and yield. Objectives were to document the change in nutrient content, yield, and growth stage of alfalfa grown in Utah as it matures and to develop a simple model to predict optimal harvest date. The study involved three locations in major alfalfa producing regions in Utah. Samples were collected from three commonly grown alfalfa varieties between 26 April and 26 September in 1987. Maximum and minimum levels of crude protein (CP) observed were …

N2-Fixation In Alfalfa (Medicago Sativa L.) Seedlings And Rhizobium Meliloti L. Grown In Vitro Under Salt And Drought Stresses, Ramzi Muhiddin Mohamad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alfalfa, Medicago sativa L., cultivars, breeding lines and germplasm releases (populations) and Rhizobium meliloti L. strains that exhibit nitrogen fixation efficiency and tolerance to salinity and drought stresses should enhance seedling establishment, increase yields, reduce nitrogen dependency on petroleum-based nitrogen fertilizers, and allow wider use of irrigated lands in semiarid and a rid regions. In vitro experiments were conducted to determine relative salt (sodium chloride -- NaCl) tolerance: l) during germination and early seedling growth of 229 alfalfa populations from North Africa, the Middle East and the United States, 2) survival and growth of 92 rhizobial strains obtained from different …

A Study Of Ultrastructural Changes In Tolerant And Susceptible Lines Of Alfalfa Induced By Stem Nematode (Ditylenchus Dipsaci Kühn), Dorris C.N. Chang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fine structural analyses of host tissue (alfalfa, Medicago sativa L.) response to infection by the stem nematode (Ditylenchus dipsaci Kühn) were conducted. Hypocotyl regions were taken on 1,3 and 7 days after inoculation.

Electron micrographs of infected tissue indicated the types of damage were the same between Lahontan (tolerant line) and Ranger (susceptible line). Only the infection rate (in percent) and degree of damage were different between lines and among the different temperatures (15, 20 and 25 C). The higher the temperature, the more injury resulted. After 3 to 7 days of infection, the symptoms observed were swelling and …

Quantitative Evaluation Of Saponin Content In Du Puits Alfalfa Foliage (Medicago Sativa L.) With Trichoderma, Wang Li-Chun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Selections in Du Puits alfalfa (Medicago sativa L. ) were evaluated for saponin content. The data obtained from the Trichoderma bioassay were converted to saponin values by regressions and standard curves. It was necessary to adjust the concentration of alfalfa extract in the bioassay so that the saponin content in alfalfa was estimated in that portion of the curve showing a marked response to saponin. A different regression was established for each group of low and high saponin plants of Du Puits alfalfa. The standard curve prepared with extract of Du Puits alfalfa used on the basis of its …

The Free Sterol Content Of Selected Clones Of Alfalfa As Related To Seed Infestation By The Alfalfa Seed Chalcid, Rex Alton Richards

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The infestation of twelve selected clones of alfalfa by the alfalfa seed chalcid was measured. The free sterol content of the stems, leaves, flowers and pods of these clones was determined. A check was made to see if there was a correlation between the sterol content and the chalcid infestation.

Differences were found among the clones in the sterol content for each plant part. There were also significant differences in percent chalcid infestation in the 12 clones. Duncan's New Multiple Range Test pointed out which clones differed Significantly from the others.

Using linear regression analysis, the correlation coefficient of the …

Saponin Content And Some Pod And Blossom Characteristics Of Alfalfa As Related To Seed Infestation By The Alfalfa Seed Chalcid, Ronald D. Morse

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The alfalfa seed chalcid, Bruchophagus ruddi Guss., is a jet-black hymenopteran wasp. The destructive nature of this pest has been recognized since the latter part of the nineteenth century. Every year thousands of acres of alfalfa seed are destroyed, with infestation reaching as high as 8 5 percent in some areas. In Utah the chalcid annually ruins from 5 to 25 percent of the alfalfa seed. Much of this damage goes unnoticed, as infested seed is commonly blown out in the trash during harvesting and cleaning operations . The extent of damage is not restricted to the United States. Wherever …

An Ecological Study Of Ditylenchus Dipsaci (Kuhn) Filipjev. In A Field Of Alfalfa, Shu-Ten Tseng

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ditylenchus dipsaci (Kuhn) Filipjev. is one of the most destructive nematodes to crop plants. It attacks and damages more than 300 species of cultivated and uncultivated plants. The nematode can be differentiated into many races, each of them having a preference for a group or even a single plant species.

Alfalfa stem nematode is one of the races in this species which attacks the above ground portion of alfalfa but does not infest the roots. Larvae of this nematode may migrate from the plant tissue to soil in moist conditions. These nematodes migrate actively to nearby plants or are carried …

A Survey Of The State Of Utah For Areas Infested With The Stem Nematode Of Alfalfa, Dwayne R. Buxton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant nematodes belong to a large group of invertebrates known as round worms, They derive their name from the Greek word "nema," meaning thread. In literature some authors refer to nematodes as nemas. In England and many parts of the United States, plant-parasitic nematodes are called eelworms.

While some damage to plants results from mechanical injury, salivary secretions injected by the nematode into the plant are usually the major cause of damage. Experiments conducted in the first part of the present century have demonstrated large differences in plant growth in soil infested with nematodes and soil freed of nematodes by …

Alfalfa Resistance To The Clover Seed Chalcid Bruchophagus Gibbus (Boheman), Gerald Douglas Minion

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The destructive nature of the clover seed chalcid has been known since the latter part of the 19th century. This jet-black Hymenoptera, often called the "chalcis-fly," destroys from 10 to 20 percent of the alfalfa seed in Utah each year. Damage as high as 85 percent has been reported.

General And Specific Combining Ability Of Five Alfalfa Clones Including Reciprocal Effects For Seedling Vigor And Seed Yield, Edwin Theodore Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The use of F₁ hybrids for commercial production of such cross-pollinated crops as corn, sorghum, sugar beets, onions, and pearl millet suggests the feasibility of using this technique for alfalfa. Production of F₁ hybrids of commercial value is dependent on the use of breeding material expressing good combining ability. In order to obtain precise estimates of combining ability for quantitative characters in alfalfa, it is necessary to produce all possible single crosses among a number of parents. The single cross seed required is difficult to obtain due to the vegetative reproduction and isolation required; and, subsequently, limited testing …

The Use Of Tetrazolium As A Measure Of The Salt Tolerance Of Alfalfa, Daryl A. Freter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The task of obtaining and selecting plants which may not only survive under salty conditions, but grow and produce satisfactory yields is varied and complex. It is becoming necessary to select and breed crops for salt tolerance. Plants can be grown in artificially constructed salt basins to test their individual salt tolerance, but this takes time, at least one year. It would be desirable to develop a rapid test to determine the salt tolerance of a given plant. The use of a dye in conjunction with a series of salt solutions has been suggested for determining the salt tolerance of …

Resistance To And Transmission Of Witches' Broom And Comparative Yields Of Alfalfa Varieties In The Uintah Basin, Utah, David Val Glover

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alfalfa is the most important forage crop in Utah. It is of particular importance to the Uintah Basin, Utah area where alfalfa hay and seed production are major sources of agricultural income. This crop owes much of its popularity to the fact that it will normally produce large yields of good forage on land which is unsuited to more intensive cultivation. In many cases it is impractical to advocate disease control practices which involve extra labor or expense and as a result most diseases of alfalfa, if controlled at all, are controlled by the use of resistant varieties.

During the …

Seedling Establishment Of Alfalfa Comparing Four Varieties, Three Fungicides And Two Inoculums, Ronald Brown Foster

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The establishment of alfalfa is expensive and good initial stands permit the farmer to secure high yields and spread establishment costs over several years, Of the factors involved: seedbed preparation, fertilization, seed viability, method of planting, and water application are controlled by the farmer, On the other hand, beneficial and detrimental microflora are not so easily controlled because practices aimed at controlling the detrimental microflora may also destroy the beneficial.

Control Of Dodder In Alfalfa Seed Crops, William Orvid Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dodder (Cuscuta spp.) is a parasitic weed which attacks alfalfa, clovers, lespedeza, and many other species of plants. This pest is especially troublesome when these crops are grown to produce seed.

Control of dodder should increase the financial income of a seed producer in several ways. First, control should make it possible for a producer to raise seed of high quality which will command a better price; second, it should enable the producer to increase yields; and last, it should eliminate much of the cost of harvesting and cleaning his product.

Where dodder is present in seed, the grower …

Seed And Forage Production In Four Clonal Lines Of Alfalfa As Influenced By Lygus Infestation, John Keith Noyes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

No other forage crop cultivated in the United States can be used in as many ways as alfalfa. The variety of its uses make it a most useful forage crop.

The distribution of alfalfa is world wide and it plays a leading role in the production of livestock and their products. For general feeding of farm animals, alfalfa is unsurpassed. Used for pasture, it has a high capacity, which leads to large gains in grasing animals. If properly rotated and cared for, it adds nitrogen to the soil in a form that is available to plants and thereby increases crop …

Nitrogen Content And Protein Yield Of Alfalfa As Influenced By Variety, William H. Bennett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-four alfalfa varieties, representing four varietal groups, were compared for nitrogen content and protein yield. A highly significant difference between varieties was noted for nitrogen content, and a significant difference for protein yield. Saskatchewan 666 had the highest content in the first cutting, but Ledak 22009 had the highest content in the third. Group differences were not significant. Crop differences were highly significant for nitrogen content, yield of forage, and of protein. In the case of every variety, the third cutting was richer in nitrogen than the second and the seemed was richer than the first. Protein yield, however, was …

Stem Blight Of Alfalfa In Utah: A Complex Of Two Distinct Diseases, William E. Rader

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In 1908, Sackett described for the first time what appeared to be a new bacterial disease of alfalfa in Colorado. To this particular disease he applied the name “stem blight" and attributed the cause to a bacterium, Pseudomonas medicaginis n. sp. For some two decades or more Sackett's work on this disease was accepted. During this time stem blight, which was first thought to be indigenous to the western United State, was reported from nine states east of the Rocky Mountains. In 1933, Johnson and Valleau described a disease of alfalfa, characterized by stem lesions very similar in appearance to …

Temperature And Atmospheric Humidity As Factors Influencing Seed Setting In Alfalfa, Lealand A. Clark

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For many years seed growers have thought that definite relationships existed between seed production and the weather. When this subject is approached there is little unity of opinion, even among neighboring seed growers. This lack of unity would indicate that growers generally are aware of some cause which affects seed setting, but they are not certain that any particular condition of the weather is the chief contributing factor. Scientific writers¹ on the subject are also confident that weather is probably one of the major factors influencing seed production.

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 …