Digital Commons Network^™

Long-Term Effects Of Rice Rotation, Tillage, And Fertility On Near-Surface Soil Carbon And Nitrogen Cycling, Jill Marie Motschenbacher

Graduate Theses and Dissertations

Rice (Oryza sativa L.)-based cropping systems are different from other row crops due to the flood-irrigation scheme used from about one month after planting to a few weeks prior to harvest. The frequent cycling between anaerobic (i.e., flooding during the growing season) and aerobic (i.e., generally, the remainder of the year) conditions can influence the rate of soil organic matter (SOM) decomposition, which can greatly influence carbon (C) and nitrogen (N) storage and sequestration in the soil over time. Therefore, a study was conducted on a silt-loam soil (fine, smectitic, thermic, Typic Albaqualf) at the Rice Research and Extension Center …

Returns To The Introduction Of New Sorghum Cultivars Into The Dairy Industry Of El Salvador, Alexis Homero Villacís Aveiga

INTSORMIL Scientific Publications

The returns to the introduction of new photo-insensitive sorghum varieties into the dairy industry were analyzed to determine changes in the welfare of consumers, processors, producers and the society. The economic surplus method was used along with a survey data of a stratified sample of 150 farms conducted in 2011 in El Salvador. Results indicate that there are large returns per dollar spent and substantial benefits to consumers, processors and producers. Results also show that the adoption of these new technologies represents advantages in production costs of milk in each farm size. These cost savings per bottle are very small …

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, …

Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann

Biological Sciences

The pocket gopher (Thomomys bottae) and voles (Microtus spp.) cause significant economic damage to vineyards. In response, many growers have taken steps to attract Barn Owls (Tyto alba) to their properties to help keep these rodent populations in check. This research project investigated Barn Owl consumption of pocket gophers and voles in Central California vineyards in order to assess the efficiency of this integrated pest management strategy. I collected a total of 715 owl pellets from five vineyard locations in Templeton and Paso Robles, California over an eight-month period during nesting and post-fledging seasons. I …

Wayne E. Sabbe Arkansas Soil Fertility Studies 2011, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

Igrow Wheat: Best Management Practices For Wheat Production, David C. Clay, C. Gregg Carlson, Kevin Dalsted

Agronomy, Horticulture, and Plant Science Books

No abstract provided.

Modeling An Improvement In Phosphorus Utilization In Tropical Agriculture, David Edelstein, David J. Tonjes

Technology & Society Faculty Publications

Studies of Terra Preta soils have generated interest in recreating their fertility elsewhere. Much of the research has focused on soil amendment charcoal (“biochar”). Terra Preta also contains bone fragments, producing a high concentration of phosphorus. Some forecast worldwide declines in phosphorus supplies, and better agricultural system management is required to improve phosphorus use efficiency. A conceptual model is offered to consider the influence of charcoal on bioavailability of phosphorus. The model describes a system where improvements in the chemical and biological condition of the soil result in increased phosphorus availability and cycling. Mechanisms of phosphorus/charcoal interaction are considered, and …

Effectiveness Of Grass Filters In Reducing Phosphorus And Sediment Runoff, Ahmed Al-Wadaey, Charles S. Wortmann, Thomas G. Franti, Charles A. Shapiro, Dean E. Eisenhauer

Department of Agronomy and Horticulture: Faculty Publications

Surface water contamination can often be reduced by passing runoff water through perennial grass filters. Research was conducted in 2006 to 2008 to evaluate the size of cool season grass filters consisting primarily of tall fescue (Festuca arundinacea Schreb) with some orchard grass (Dactylis glomerata L.) relative to drainage area size in reducing runoff sediment and phosphorus (P). The soil was Pohocco silt loam Typic Eutrochrepts with a median slope of 5.5%. The grass filters occupying 1.1 and 4.3% of the plot area were compared with no filter with four replications. The filters were planted in the V-shaped …

The Effects Of Climate On The Growth Of Winter Wheat And Spring Barley In An Irish Context, Adrian Kennedy

Theses

The climate of earth is always changing due to natural events, however it is thought that the rapid warming period currently taking place is primarily due human activity to (environmental protection agency 2012). Climate change is altering the environment and this will have consequences for agriculture (Teagasc publications 2012). In this study we examine the relationship between weather and the yield of winter wheat and spring barley in an Irish context using data gathered from 2004-2010 at the Teagasc Oak Park research centre in Carlow. The data was analysed using a mixed effect model to test which if any weather …

Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Achieving agronomic and environmental benefits associated with cover crops oft en depends on reliable establishment of a highly productive cover crop community. The objective of this study was to determine if cover crop mixtures can increase productivity and stability compared to single species cover crops, and to identify those components most active in contributing to or detracting from mixture productivity. A rainfed field experiment was conducted near Mead, Nebraska, United States, in 2010 and 2011. Eight individual cover crop species (in either the Brassicaceae [mustard] or Fabaceae [legume] family) and four mixtures of these species (two, four, six, and eight …

Agriculture And Food In Crisis: Conflict, Resistance, And Renewal [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by Fred Magdoff and Brian Tokar. 2010. Monthly Review Press, New York, New York, United States. 348 p. Paperback, cloth US$ 75.00, paper US$ 18.95, ISBN-13 978-1-58367-226-6.

That doubling of food production over the next four decades will be needed to adequately nourish our human population is not news, but the incredible steps essential to achieve that goal and their political and social implications are less well reported. In this series of 16 essays edited by Fred Magdoff and Brian Tokar, several thoughtful specialists in global food issues explore the historical, biological, economic, energy, political and social dimensions of …

Cultivating A Movement: Excerpts From An Oral History Of Organic Farming And Sustainable Agriculture On California’S Central Coast [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by I. Reti and S. Rabkin, 2011. University of California, Santa Cruz, Library, Santa Cruz, California, United States. 299 p., US$19.95, ISBN 9-780972-33431, paper.

Often the most compelling evidence for success of organic farming comes from the personal stories of farmers. Coupled with reports on the application of science in organics, the practical knowledge of people in the field provides a rich foundation for the ongoing growth of this intriguing sector of the food system. This collection of interviews by the staff of the Regional History Project is one unique activity of the University of California, Santa Cruz library, …

Returns To The Introduction Of New Sorghum Cultivars Into The Dairy Industry Of El Salvador, Alexis H. Villacís, John H. Sanders

INTSORMIL Presentations

The driver of agricultural development is the introduction of new technology. Sensitive sorghums have long been a critical component of hillside Central American agriculture providing a reserve or insurance policy when the principal staple of maize falters. The insensitive sorghums have been more recently introduced since the ‘70s for planting in the valleys in the second season. In the last thirty years the introduction of new insensitive cultivars has accelerated initially for poultry and in the previous two decades for dairy production. This growth has been facilitated by strategic investments in research by CENTA and the Ministry of Agriculture.

As …

Climate Change And Climate Variability: El Salvador – Impacts On Productivity Of Grain Crops And Opportunities For Management And Improvement, P. V. Vara Prasad

INTSORMIL Presentations

1. Climate change and climate variability (past and future).

2. Climate change and variability in El Salvador (climate models).

3. Impact of temperature on grain yield of dry bean, maize and sorghum in El Salvador (crop simulation models).

4. Effects of temperature, drought and/or carbon dioxide: experimental evidence (response of grain sorghum, maize and dry bean).

5. Opportunities for crop management and genetic improvement.

Soil Test And Phosphorus Rate For High Rainfall Clover Pastures, Robert Summers, David Weaver

Bulletins 4000 -

Essential information for soil testing to determine the phosphorus fertiliser requirements for clover pastures in high rainfall coastal areas of Western Australia. Includes procedures for soil sampling, tissue testing, liming, when to apply fertiliser, how to decide on the target production level, how much fertiliser is required and type of fertiliser.

Screening Synteny Blocks In Pairwise Genome Comparisons Through Integer Programming, Haibao Tang, Eric Lyons, Brent S. Pedersen, James C. Schnable, Andrew H. Paterson, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Background:

It is difficult to accurately interpret chromosomal correspondences such as true orthology and paralogy due to significant divergence of genomes from a common ancestor. Analyses are particularly problematic among lineages that have repeatedly experienced whole genome duplication (WGD) events. To compare multiple “subgenomes” derived from genome duplications, we need to relax the traditional requirements of “one-to-one” syntenic matchings of genomic regions in order to reflect “one-to-many” or more generally “many-to-many” matchings. However this relaxation may result in the identification of synteny blocks that are derived from ancient shared WGDs that are not of interest. For many downstream analyses, we …

Impact Of Climate Change And Climate Variability On Productivity Of Grain Crops, P. V. Vara Prasad

INTSORMIL Presentations

1. Climate change and climate variability (past and future). 2. Temperature and carbon dioxide: response of grain sorghum and dry bean. 3. Climate change and variability in El Salvador (climate models). 4. Impact of temperature increaseongrainyieldofsorghum,maizeanddrybeaninElSalvador(cropsimulationmodels). 5.Concludingremarks.

Wheat Yield Potential And Land Management Constraints In The South West Of Western Australia, Dennis Van Gool

Resource management technical reports

This report provides the underpinning information to help improve the long term profitability of wheat cropping. It documents the realistic potential yield of the 18 million hectares of agricultural land in the South West of Western Australia and the gap between this potential and the actual yields, based on shire averages. This report also summarises major land management constraints that limit the yield potential. This information can be used to aid strategic planning at different levels, for example state, shire and, with care, as a starting point for farm planning.

Crop Updates 2011 - Nutrition, Precision Agriculture & Climate And Forecasting, Deb Archdeacon, Andrew Gulliver, David Cullen, Qifu Ma, Richard Bell, Ross Brennan, Craig Scanlan, Wen Chen, Geoff Anderson, Mike Bolland, Peter Rees, Sandy Alexander, Frank D'Emden, Stephen Davies, Breanne Best, Louise Barton, Klaus Butterbach-Bahl, Ralph Kiese, Daniel Murphy, Peter Newman, Roger Mandel, Roger Lawes, Michael Robertson, Derk Bakker, Jeremy Lemon, Alison Lacey, John Paul Collins, Glen Riethmuller, Fiona H. Evans, David Stephens, Caroline Peek, Tim Scanlon

Crop Updates

This session covers sixteen papers from different authors:

Nutrition

1. Balance® used in conventional cropping practice with half of the upfront fertiliser rate can sustain crop yield and build soil biological fertility, Deb Archdeacon1, Andrew Gulliver2 and David Cullen2, 1Agronomica, Wellington Mill, WA, 2Custom Composts, Nambeelup, WA

2. Effects of potassium (K) supply on plant growth, potassium uptake and grain Yield in wheat grown in grey sand, Qifu Ma1, Richard Bell1, Ross Brennan2 and Craig Scanlan2, 1School of Environmental Science, Murdoch University, 2Department of Agriculture and Food

3. Improving fertiliser management: redefining the …

Crop Updates 2011 - Farming Systems, Janette Drew, Rob Grima, Bob French, Raj Malik, Mark Seymour, Christine Zaicou-Kunesch, Glenn Mcdonald, Brendon Nicholas, Dennis Van Gool, James Fisher, Peter Tozer, Doug Abrecht, Michael Robertson, Cameron Weeks, Michael O'Conner, Peter Newman, Mike Clarke, Andrew Blake, Gordon Macaulay, Vijay Jayasena, Syed M. Nasar-Abbas, Larisa Cato, Robert Loughman, Ken Quail

Crop Updates

This session covers twelve papers from different authors:

1. Fallowing 50% of the farm each year – does it pay? Janette Drew and Rob Grima

Department of Agriculture and Food

2. How crop sequences affect the productivity and resilience of cropping systems in two Western Australian environments, Bob French, Raj Malik, Mark Seymour, Department of Agriculture and Food

3. When is continuous wheat or barley sustainable? Christine Zaicou-Kunesch and Rob Grima Department of Agriculture and Food

4. Identifying constraints to bridging the yield gap, Glenn McDonald, Department of Agriculture and Food

5. Land constraints limiting wheat yields in …

Crop Updates 2011 - Cereals, David Bowran, Bill Crabtree, Peter Carberry, Peter Burges, Bevan Buirchell, Ben Curtis, Sarah Ellis, Brenda Shackley, Christine Zaicou, Siva Sivapalan, Penny Goldsmith, Gae Plunkett, Darshan Sharma, Mario D'Antuono, Art Diggle, Peter Mangano, Sally Peltzer, Michael Renton, Bill Macleod, Fumie Horiuchi, George Wyatt, Geoff Anderson, Richard Bell, Ross Brennan, Wen Chen, Penny Riffkin

Crop Updates

This session covers eleven papers from different authors:

OPENING, NEW CROP VARIETIES & DECISION SUPPORT

Opening

1. Overview of the 2010 season, David Bowran, Director, Practice and Systems Innovation, Department of Agriculture and Food,

2. My experience in a drought as a farmer and consultant, Bill Crabtree, Morawa, Western Australia

3. Meeting the productivity and sustainability challenges to Australian agriculture until 2030, Peter Carberry, CSIRO Sustainable Agriculture Flagship

New Crop Varieties

4. National Variety Trials (NTV) wheat variety performance – captivity vs broadacre, Peter Burgess, Kalyx Agriculture

5. WALAN2289 – a new lupin variety to replace …

Managing Complexity In Modern Farming, Ross Kingwell

Natural Resources Research Articles

Modern farming in Australia is no longer simple. Farms are large, multi-enterprise businesses underpinned by expensive capital investments, changing production technologies, volatile markets and social challenges. The complexity of modern broadacre farming leads to the question: what is the nature of the relationship between farm business complexity and farm profitability? This study uses bioeconomic farm modelling and employs eight measures of complexity to examine the profitability and complexity of a wide range of broadacre farming systems in Australia. Rank order correlations between farm profitability and each measure of complexity show inconsistent relationships, although the most profitable farming systems are found …

Modeling Gross Primary Production Of Irrigated And Rain-Fed Maize Using Modis Imagery And Co2 Flux Tower Data, Joshua L. Kalfas, Xiangming Xiao, Diana X. Vanegas, Shashi B. Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

Abstract

Information on gross primary production (GPP) of maize croplands is needed for assessing and monitoring maize crop conditions and the carbon cycle. A number of studies have used the eddy covariance technique to measure net ecosystem exchange (NEE) of CO₂ between maize cropland fields and the atmosphere and partitioned NEE data to estimate seasonal dynamics and interannual variation of GPP in maize fields having various crop rotation systems and different water management practices. How to scale up in situ observations from flux tower sites to regional and global scales is a challenging task. In this study, the Vegetation …

Plant Growth In Soil Amended With Drilling Mud, Satoshi Takaki, Duane C. Wolf

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Extraction of natural gas generates drilling fluid and drilling mud that contain high concentrations of salts. Land application of the fluid and mud can have negative impacts on plant growth and soil properties. The objective of this study was to determine the effects of drilling mud on plant growth, plant chemical concentrations, and soil chemical properties. Sudangrass (Sorghum sudanense [Piper] Stapf [Piper]) and bermudagrass (Cynodon dactylon L.) were grown in a Roxana loam soil amended with 0%, 5%, or 10% (w/w) drilling mud in a 6-wk greenhouse study. Plant biomass production and concentrations of elements in biomass were determined. Electrical …

Subsurface Compaction A Guide For Wa Farmers And Consultants, Stephen Davies, Alison Lacey

Bulletins 4000 -

For plants to grow in agricultural soils, roots and emerging shoots must be able to force their way through the soil. In soils of high strength, this growth is physically restricted. High strength soils may be due to natural soil characteristics and conditions or develop as a result of agricultural practices and may be in layers or throughout the soil profile.

In agriculture, high strength soils commonly occur as a result of compaction. Compaction of agricultural soils can be in the surface (often caused by stock trampling or rain drop splatter) or in the subsurface (usually in a layer at …

Farmers' Markets In Kentucky: A Geospatial, Statistical, And Cultural Analysis, Elizabeth Ann Schmitz

Masters Theses & Specialist Projects

To assess what factors are driving the exponential growth of farmers’ markets in Kentucky, geospatial and statistical analysis of a database of 121 farmers’ markets was conducted. A statewide survey of market leaders and a case study of a single farmers’ market both identified reasons for growing support of farmers’ markets in Kentucky.

Market distribution, vendor levels, and gross sales were mapped against a backdrop of county urban classification, median household income, and education levels. Kruskal-Wallace analysis was used to identify if Kentucky’s rural, micropolitan, and metropolitan markets differ significantly in terms of their age, number of vendors, and market …

Effect Of Mica Content On Surface Infiltration Of Soils In Northwestern Kern County, California, Steven Keyes Stakland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A soils infiltration rate (IR) is the measured rate that soil is able to absorb water, either from precipitation or irrigation. A low IR can cause damage to crops if the necessary amount of water cannot penetrate to the plant roots in the time needed. The damage can be common in permanent plantings such as almond and pistachio orchards where regular tillage is avoided. This indicates a physical aspect to the problem because tillage increases IR. However, there is also an electrochemical side to infiltration problems because certain calcium surfactant treatments can increase IR. Various other methods have been used …

Genetic Mapping Of Quantitative Trait Loci Associated With Bioenergy Traits, And The Assessment Of Genetic Variability In Sweet Sorghum (Sorghum Bicolor (L.). Moench), Aatshwaelwe Lekgari Lekgari

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Sweet sorghum, a botanical variety of sorghum is a potential source of bioenergy because high sugar levels accumulate in its stalks. The objectives of this study were to explore the global diversity of sweet sorghum germplasm, and map the genomic regions that are associated with bioenergy traits. In assessing diversity, 142 sweet sorghum accessions were evaluated with three marker types (SSR, SRAP, and morphological markers) to determine the degree of relatedness among the accessions. The traits measured (anthesis date [AD], plant height [PH], biomass yield [BY], and moisture content [MC]) were all significantly different (P< 0.05) among accessions. Morphological marker clustered the accessions into five groups based on PH, MC and AD. The three traits accounted for 92.5% of the variation. There were four and five groups based on SRAP and SSR data respectively classifying accessions mainly on their origin or breeding history. The observed difference between SSR and SRAP based clusters could be attributed to the difference in marker type. SSRs amplify any region of the genome whereas SRAP amplify the open reading frames and promoter regions. Comparing the three marker-type clusters, the markers complimented each other in grouping accessions and would be valuable in assisting breeders to select appropriate lines for crossing. In evaluating QTLs that are associated with bioenergy traits, 165 recombinant inbred lines (RILs) were planted at four environments in Nebraska. A genetic linkage map constructed spanned a length of 1541.3 cM, and generated 18 linkage groups that aligned to the 10 sorghum chromosomes. Fourteen QTLs (6 for brix, 3 for BY, 2 each for AD and MC, and 1 for PH) were mapped. QTLs for the traits that were significantly correlated, colocalized in two clusters on linkage group Sbi01b. Both parents contributed beneficial alleles for most of traits measured, supporting the transgressive segregation in this population. Additional work is needed on exploiting the usefulness of chromosome 1 in breeding sorghum for bioenergy.

Evapotranspiration Of Kentucky Bluegrass, Lynda L. Fenton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rapid population growth in arid regions of the western US is placing increased demand on water resources. Variability in precipitation and common occurrence of drought have promoted scrutiny of water use in urban lawns and gardens. However, few reliable measurements of water use of these landscapes exist. Quantifying the amount of water used vs. required by landscapes such as turfgrass would allow significant water conservation. Evapotranspiration (ET) is affected by biophysical factors such as: available energy, turbulent mixing, saturation deficit, soil water, and stomatal conductance. In order to simulate the water use by turfgrass, the relative importance of these processes …

Optimizing The Physical And Nutritional Environment Of Unleached Root-Zones, Curtis B. Adams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Unleached root-zones represent an environmental ideal by eliminating wasteful leaching of nutrients and water. NASA grows plants in space in unleached root-zones, incorporating polymer-coated fertilizer (PCF) into a ceramic media (Turface or Profile). However, lack of growth productivity in space has led to the need for research to improve the nutritional and physical environment of the root-zone, which is the objective of this research. PCF types are diverse in release characteristics and the effects of temperature and substrate water content have not been well characterized. In spite of widespread use, studies on chemical properties and applied studies to verify soil …