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Precision Drought Stress In Orchards: Rootstock Evaluation, Trunk Hydration And Canopy Temperature, Lance V. Scott 2017 Utah State University

Precision Drought Stress In Orchards: Rootstock Evaluation, Trunk Hydration And Canopy Temperature, Lance V. Scott

All Graduate Theses and Dissertations

In many areas, over half of all diverted water is used for irrigation. Tree fruit crops use a lot of water, but water productivity can be increased using properly-timed precision water stress. In addition to water conservation, increases in water productivity arise from better fruit quality, increased storage life and reductions in pruning and maintenance. One major hurdle to applying precision water stress in orchards is the lack of a reliable, automated method of determining tree water status. However, the influence of physiological characteristics such as rootstock vigor on water productivity are also important. Selecting the most appropriate rootstocks and ...


G-Quadruplex (G4) Motifs In The Maize (Zea Mays L.) Genome Are Enriched At Specific Locations In Thousands Of Genes Coupled To Energy Status, Hypoxia, Low Sugar, And Nutrient Deprivation, Carson M. Andorf, Mykhailo Kopylov, Drena Dobbs, Karen E. Koch, M. Elizabeth Stroupe, Carolyn J. Lawrence, Hank W. Bass 2017 United States Department of Agriculture

G-Quadruplex (G4) Motifs In The Maize (Zea Mays L.) Genome Are Enriched At Specific Locations In Thousands Of Genes Coupled To Energy Status, Hypoxia, Low Sugar, And Nutrient Deprivation, Carson M. Andorf, Mykhailo Kopylov, Drena Dobbs, Karen E. Koch, M. Elizabeth Stroupe, Carolyn J. Lawrence, Hank W. Bass

Drena Dobbs

The G-quadruplex (G4) elements comprise a class of nucleic acid structures formed by stacking of guanine base quartets in a quadruple helix. This G4 DNA can form within or across single-stranded DNA molecules and is mutually exclusive with duplex B-form DNA. The reversibility and structural diversity of G4s make them highly versatile genetic structures, as demonstrated by their roles in various functions including telomere metabolism, genome maintenance, immunoglobulin gene diversification, transcription, and translation. Sequence motifs capable of forming G4 DNA are typically located in telomere repeat DNA and other non-telomeric genomic loci. To investigate their potential roles in a large-genome ...


Corn Tassels, Silks And Blades, R. P. Speer 2017 Iowa Agricultural College

Corn Tassels, Silks And Blades, R. P. Speer

Bulletin (Iowa Agricultural Experiment Station)

Large com crops in Iowa, point to general prosperity; but poor com means more or less want and suffering, as it is the crop upon which people depend most for a living. Good farmers have grown 75 bushels of corn per acre frequently in Iowa in ordinary seasons; but generally, the average yield per acrc is not more than half of the number of bushels just named. The causes of the difference between good and poor crops can be traced easily, to differences between the methods of preparing and tilling the soil and differences between varieties of corn. On the ...


Bacterial Activities And Crop Production, Percy Edgar Brown 2017 Iowa State College

Bacterial Activities And Crop Production, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Until the present time studies in soil bacteriology have dealt almost exclusively with the occurrence and activities of microorganisms in the soil and no attempt has been made to interpret experimental results from the standpoint of crop production. This is due, of course, to the fact that as a science soil bacteriology is scarcely out of its infancy and the preliminary investigations in any science must of necessity deal mainly with underlying principles and such studies are always apt to be rather fragmentary in character.


Determination Of Amino Acids And Nitrates In Soils: Amino Acids, Ammonia And Nitrates In Manured And Limed Soil, R. S. Potter, R. S. Snyder 2017 Iowa State College

Determination Of Amino Acids And Nitrates In Soils: Amino Acids, Ammonia And Nitrates In Manured And Limed Soil, R. S. Potter, R. S. Snyder

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

In view of the fact that no data had ever been obtained on the quantitative relationships of the organic material in the soil by such methods as would preclude a chemical transformation, two things seemed desirable, in continuing the humus investigations at the Iowa Agricultural Experiment Station. First, to attempt the analysis of the organic material of the soil without subjecting it to hydrolysis or other chemical change, and second, to correlate the proportionate quantities of the compounds or classes of compounds found with the kind of soil, its history, treatment, fertility, etc.


Sulfofication In Soils, P. E. Brown, E. H. Kellogg 2017 Iowa State College

Sulfofication In Soils, P. E. Brown, E. H. Kellogg

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Sulfur has long been known to be one of the essential plant food constituents. It has always been believed, however, that there was sufficient present in all soils for the optimum growth of crops. This assumption has been very largely based on Wolff's analyses of the ashes of various crops which showed the presence of very small amounts of sulfur.

The recent work of many investigators has demonstrated, however, that the amount of sulfur in plant materials as determined in the ash is, in most cases, entirely too low; that there is a considerable loss of sulfur in the ...


The Determination Of Ammonia In Soils, R. S. Potter, R. S. Snyder 2017 Iowa State College

The Determination Of Ammonia In Soils, R. S. Potter, R. S. Snyder

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Theoretically, the ideal method for determining ammonia in soils would give the absolute amount of ammonia present as such and as the ammonium radical, but in the light of present knowledge, it cannot be said beyond all doubt that any conceivable method would give this ideal result. This is true because a large part of the nitrogen of the soil is present in protein and protein degradation products, the extensive decomposition of which gives large amounts of ammonia. The uncertainty regarding just what products are present does not permit the finding of conditions which we can be certain will expel ...


Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The conclusions which may be drawn from the experiments upon the effects of barnyard manure on bacteriological activities of field S'oils presented in this bulletin are as follows:

1. Applications of manure up to sixteen tons per acre increased the numbers of organisms in the soil as shown by the growth on modified synthetic and albumen agar. The ammonifying power of the soil as shown by tests with the casein-fresh soil, albumen-fresh soil, dried blood-fresh soil, and dried blood-air-dried soil methods, and the nitrifying power tested by the ammonium sulfate-fresh soil, and the ammonium sulfate-air- dried soil methods were ...


Small Pasture Management Guide For Utah, James Barnhill, Shawn Olsen, Randy Sessions, Dean Miner, Tiffany Julen-Day, Niels Hansen, Clark Garn 2017 Selected Works

Small Pasture Management Guide For Utah, James Barnhill, Shawn Olsen, Randy Sessions, Dean Miner, Tiffany Julen-Day, Niels Hansen, Clark Garn

Shawn Olsen

No abstract provided.


Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown 2017 Iowa State College

Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. In the different soil types, as well as in the same soil under different rotations, the greatest number of organisms occurred at a depth of 4 inches.

2. Bacteria were found in considerable numbers at much lower depths in the loess soil than in the drift soil.

3. There was a more or less gradual decrease in numbers to a depth of 3, 5 and in one case of fifteen feet. No sudden increases were observed even where gains in moisture occurred.

4. The greatest decrease in numbers of organisms occurred within the first 12 inches and in some ...


Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

From a bacteriological study of soil plots under both continuous cropping and various crop rotations, these general conclusions were drawn:

1. The rotation of crops caused the development of greater numbers of organisms in the soil and of greater ammonifying, nitrifying, and nitrogen-fixing power by the soil, than continuous cropping either to corn or to clover.

2. Greater numbers of organisms, greater ammonifying, nitrifying, and nitrogen-fixing powers were found in a soil under a three year rotation of corn, oats, and clover, than in a soil under a two year rotation of corn and oats, or in a soil under ...


Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Applications of limestone up to three tons per acre increased the total number of soil bacteria which develop on "modified synthetic" agar plates.

2. These increases probably occurred in species more resistant to drought.

3. The three ton application gave a proportionately greater increase in numbers than the two tons.

4. Application of limestone up to three tons per acre increased the ammonlfying, the nitrifying, anil the nitrogen fixing powers of the soil.

5. The ammonification of dried blood and cottonseed meal did not run parallel in tests of field soils subjected to continued drought.

6. The three ton ...


Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith 2017 Iowa State College

Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. By means of the" modified synthetic" agar plate method bacteria are shown to be present in large numbers in a typical Wisconsin drift soil when it is completely frozen and the temperature is below zero degrees Centigrade; furthermore, increases and decreases in numbers of organisms occur during this period and large numbers are found after the soil has been frozen for a considerable period than before it begins to freeze.

2. During the fall season, the number of bacteria present in the soil diminishes gradually with the lowering of the temperature.

3. Frozen soils possess a much greater ammonifying ...


The Chemical Nature Of The Organic Nitrogen In The Soil: Influence Of Various Factors On Decomposition Of Soil Organic Matter, S. L. Jodidi 2017 Iowa State College

The Chemical Nature Of The Organic Nitrogen In The Soil: Influence Of Various Factors On Decomposition Of Soil Organic Matter, S. L. Jodidi

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

It was shown in previou' publications that the acid-soluble organic nitrogen in Iowa soils as well as in Michigan peat soils is composed chiefly of acid amides, monamino acids and diamino acids. Following those publications, and also before, other papers appeared, dealing with the isolation of organic nitrogenous compounds from soils. Thus Schreiner and Shorey succeeded in isolating from various soils, in addition to a number of non-nitrogenous bodies, the diamino acids, arginine and histidine, as well as the pyrimidine derivative, cystosine and the purine bases, xanthine and hypoxanthine. Prior to that Shorey extracted from Hawaiian soils a compound which ...


Some Bacteriological Effects Of Liming, Percy Edgar Brown 2017 Iowa State College

Some Bacteriological Effects Of Liming, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

These experiments were undertaken to determine the effects of liming on certain groups of soil bacteria in a typical Wisconsin drift soil. They justified the following general conclusions:

1. Applications of lime up to three tons per acre lead to an increase in the numbers of bacteria developing on "modified synthetic" agar. They also produce an increase in ammonification, nitrification, and in nitrogen fixation when these processes are tested by the beaker method. These increases are in all cases almost proportionate to the amount of lime applied.

2. Natural increases in numbers of bacteria tend to obscure the effects of ...


The Chemical Nature Of The Organic Nitrogen In The Soil, S. L. Jodidi 2017 Iowa State College

The Chemical Nature Of The Organic Nitrogen In The Soil, S. L. Jodidi

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

It is safe to say that among the elements which are essential for plant life, nitrogen plays the most prominent part. While nitrogen is considered to be one of the most useful constituents of soil organic matter or humus, it is the available nitrogen which is of especial value. The data given in this bulletin as well as in previous publications, show, in agreement with numerous investigations by others, that the amount of ammonia in soils is quite small, ranging from a few thousandths to a few hundredths of one per cent.


Use Of Endomaxx Mycorrhizal Seed Treatment To Improve Potato Production In Maine, John M. Jemison Jr. 2017 University of Maine Cooperative Extension

Use Of Endomaxx Mycorrhizal Seed Treatment To Improve Potato Production In Maine, John M. Jemison Jr.

Cooperative Extension - Agriculture

With the increasing cost of fertilizer and the ever-decreasing supply of apatite worldwide, improving phosphorus (P) uptake should be a goal for all producers. Due to our high levels of iron and aluminum oxides in Maine soils, P efficiency is very poor. As a result, potato farmers tend to over apply P to ensure that their crop will have adequate P. Over time, this has led to increasing plant available soil test P levels. I recently requested the Maine Soil Test Lab director for potato soil tests over the past ten years. The percentage of soils testing above 40 lbs ...


Nurse Cropping In Potato Systems, John M. Jemison Jr. 2017 University of Maine Cooperative Extension

Nurse Cropping In Potato Systems, John M. Jemison Jr.

Cooperative Extension - Agriculture

In the summer of 2016, a study was conducted at the Rogers Farm in Stillwater, Maine to study the effect of short-term nurse crops on potato yield and quality. The study was designed as a randomized complete block design with six replications. The study compared two sowing rates (winter rye at 100 vs. 200 lbs/ac) to 20 lbs of annual ryegrass or a check plot (no nurse crop). In addition, each of the winter rye treatments was either killed with an herbicide prior to one-pass hilling or just hilled. To address the question of how long to grow a ...


Towards The Development Of A Sustainable Soya Bean-Based Feedstock For Aquaculture, Hyunwoo Park, Steven Weier, Fareha Razvi, Pamela A. Peña, Neil A. Sims, Jennica Lowell, Cory Hungate, Karma Kissinger, Gavin Key, Paul Fraser, Jonathan Napier, Edgar B. Cahoon, Thomas Clemente 2017 University of Nebraska-Lincoln

Towards The Development Of A Sustainable Soya Bean-Based Feedstock For Aquaculture, Hyunwoo Park, Steven Weier, Fareha Razvi, Pamela A. Peña, Neil A. Sims, Jennica Lowell, Cory Hungate, Karma Kissinger, Gavin Key, Paul Fraser, Jonathan Napier, Edgar B. Cahoon, Thomas Clemente

Faculty Publications from the Center for Plant Science Innovation

Soya bean (Glycine max (L.) Merr.) is sought after for both its oil and protein components. Genetic approaches to add value to either component are ongoing efforts in soya bean breeding and molecular biology programmes. The former is the primary vegetable oil consumed in the world. Hence, its primary usage is in direct human consumption. As a means to increase its utility in feed applications, thereby expanding the market of soya bean coproducts, we investigated the simultaneous displacement of marine ingredients in aquafeeds with soya bean-based protein and a high Omega-3 fatty acid soya bean oil, enriched with alpha-linolenic and ...


Vegetable Gardening And Lawn Care, Jerry Goodspeed, Larry Rupp, Larry Sagers 2017 Utah State University

Vegetable Gardening And Lawn Care, Jerry Goodspeed, Larry Rupp, Larry Sagers

Larry Rupp

This course offers information on how best to care for a vegetable garden and lawn. The material covers soil preparation, planting, and general care.


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