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A Genetic Analysis Of The Rare Endemic Astragalus Ripleyi Barneby, Juan Antonio Jaramillo-Chico

Master's Theses

Astragalus ripleyi Barneby is a rare endemic species found in the San Luis Valley of the southern portions of the Rocky Mountains in Colorado and New Mexico. Though not federally listed as endangered, the species is on the Bureau of Land Management’s Sensitive Species List, warranting protection and continued management. This study aims to provide information about the genetic health of the species to inform conservation efforts and provide updated management recommendations. A genetic health analysis was conducted investigating the levels of diversity present in the species, how genetic diversity is structured across the known range of the species and …

Effects Of Photosynthetic Mode On Growth In Closely Related Tillandsia Species, Jeremy L. Read

Electronic Theses, Projects, and Dissertations

To examine the effects of photosynthetic mode (C3 vs CAM) on plant productivity, subjects of the sister taxa Tillandsia confertiflora (a C3 species) and Tillandsia latifolia (a CAM species) were grown under controlled conditions via growth chamber over 30 weeks. These subjects were divided into non-stressed and drought stress groups. Subjects were compared for total biomass gained or lost over the time period as well as physiological stress measures and CAM activity. The primary conclusion is that usage of CAM does not show major differences or tradeoffs for overall productivity. Future work is needed to clarify if this holds true …

Aegic Blogposts - Grain Industry Productivity, Ross Kingwell

Grain and other field crops published reports

The Australian Export Grains Innovation Centre (AEGIC) was an independent, not-for-profit organisation established in 2012 by the Western Australian Government and the Grains Research and Development Corporation (GRDC). Its core mission was to increase the value and international competitiveness of Australia’s multibillion-dollar export grains industry. AEGIC ceased operation at the end of 2025.

Early in its history between 20 to 30 staff from the former Western Australian Department of Agriculture were seconded to AEGIC. Following the formation of DPIRD, AEGIC continued to receive substantial annual funding support from DPIRD.

This publication is a legacy document containing collated AEGIC blog posts …

B.R. Wells Arkansas Rice Research Studies 2025, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 45.2% of total U.S. rice production and 45.7% of the total acres planted to rice in 2025. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas that produce rice. Questions …

Summaries Of Arkansas Cotton Research 2025, Fred M. Bourland

Arkansas Agricultural Experiment Station Research Series

Planted cotton acreage in Arkansas decreased in 2025 to 520,000 acres compared to 650,000 planted acres in 2024. Arkansas producers harvested 515,000 acres, which was a decrease of 125,000 acres from the 640,000 acres harvested in 2024 (https://www.nass.usda.gov/Quick_Stats/Ag_Overview/stateOverview.php?state=Arkansas&year=2025). The 515,000 harvested acres ranked Arkansas third nationally, trailing only Texas and Georgia in harvested acres (https://esmis.nal.usda.gov/sites/default/release-files/795725/cropan26.pdf). The average cotton yield, as reported by the USDA, was 1,239 lb lint/ac, which ranked fourth nationally, behind California, Louisiana, and Arizona. Arkansas farmers produced an estimated 1.329 million bales, which is a decrease from 1.788 million bales produced in 2024. This production still ranks …

Agronomic And Economic Evaluation Of Alternative Forage Crops Under Irrigation Technologies And Deficit Irrigation, Shikha Sharma

All Graduate Theses and Dissertations, Fall 2023 to Present

Water is becoming more limited in the western United States, including Utah, so farmers need forage crops that can produce well while using less irrigation water. This study examined how different forage crops respond to reduced irrigation and different irrigation application methods, and whether some crops can provide better economic returns under limited water conditions.

Field studies were conducted at three Utah locations, Cedar City, Logan, and Vernal, from 2020 to 2024. The alternative forage crops included teff, sorghum-sudangrass (sudex), and forage rye. For economic comparison, conventional forage crops included alfalfa, corn, and three-way small grains. Four to five irrigation …

Microbes In Pollination Systems: Effects On Pollinator Health, Floral Traits, Nectar Robbing, And Plant Fitness, Valerie Nicole Martin

All Graduate Theses and Dissertations, Fall 2023 to Present

Flowers produce nectar to attract pollinators, but nectar is also a habitat for yeasts and bacteria that arrive via pollinators, robbers, and other visitors. These microbes consume nectar sugars and release byproducts that change the smell and taste of nectar. Whether these changes affect how pollinators find and choose flowers, and whether they ultimately affect how many seeds a plant produces, is not well understood. In this dissertation, I studied how a common nectar yeast and a plant-associated bacterium affect the scent of wildflowers, the behavior of bumble bees and hummingbirds, and plant reproduction in montane meadows in central Colorado. …

Secure Agricultural Futures: Re-Defining And -Imagining Agricultural Water Landscapes In The Us West, Britta L. Schumacher

All Graduate Theses and Dissertations, Fall 2023 to Present

Aridity is swiftly becoming the US West’s new normal. As agricultural communities adjust to persistent growing-season scarcity, they find their livelihoods under increasing threat. This points to the urgency of finding paths toward more secure water futures. A piece of this future puzzle includes water (re-)distribution – taking excess from one place and delivering it to another in need. To begin thinking about (re-)distribution, this dissertation engages with three mixed-methods and multiscale studies. The first study pairs county-level data across the 11 westernmost US states with survey data collected from individual producers in Utah to assess past and current trends …

The Influence Of Ecological Pest Management Practices On Pests And Natural Enemies Under A Cabbage–Garden Pea Rotational System In Central Kenya, Peter Nyakundi Mageto, Milka Kiboi, Monicah Mucheru-Muna, Felix Matheri

All Peer-Reviewed Publications

Pest pressure is a major constraint on crop production in Sub-Saharan Africa, where smallholder farmers rely heavily on synthetic pesticides with potential environmental and health risks. Ecological pest management practices (EPMs) have been proposed as sustainable alternatives, although field-based evidence is limited. This study evaluated pest and natural-enemy responses to EPMs in a cabbage–garden pea rotation system over six years (2020–2025) in Central Kenya. Four treatments were assessed: homemade botanical extracts (Botanicals), coriander intercropping (Intercrop), botanical extracts combined with coriander intercropping (Botanicals + Intercrop), and a control. In cabbage, ecological treatments often recorded lower aphid and diamondback moth abundance and …

Technological Behaviour Of Pellets Containing Dried Green Crop, Christian Furll

IGC Proceedings (1977-2023)

Pelleted dried green crop presents essential advantages compared to chaff and meal as processing forms. Normally, the solidity of the pellets does not exceed the values required by animal feeding. Abrasion resulting from turnover processes is at present too high, particularly for the discharge of bins. Belt conveyors, vibrating conveyors, and bucket elevators are suitable to convey pellets. Storage of pellets over long periods has to be done by respecting prescribed climate conditions. Zones with excessive portion of abraded par­ticles in the storing pile are a preferred cause for self-heating. Slit-type dosing units as well as dosing units equipped with …

Results Of Comparative Investigations Into The Chevving And Ruminating Activities Of The Dairy Cow Fed Dried Forage From Grass And Leguminous Crops, B Piatkowski, S Nagel

IGC Proceedings (1977-2023)

The chewing and ruminating activities were studied of dairy cows fed grass, alfalfa, and straw of different physical forms. An electronic­ally controlled measuring device was applied. When feeding 8 kg of grass hay (32 % crude fibre in dry matter), the ruminating time was 5: 24 and 1 :49 hours (20,712 and 6,982 ruminat­ing movements) for chopped and ground + pelleted forages, respectively. It declined from 1 : 49 to 0: 0 l hours (from 6,929 to 70 move­ments) when hot-air dried alfalfa (23 % crude fibre) was fed in chopped and ground + pelleted forms, respectively. The ruminating time …

Feed Efficiency In Dairy Cows Of Roughages Preserved And Treated In Different Ways, M Zausch, E Boldt

IGC Proceedings (1977-2023)

Trials were conducted with dairy cows to investigate the feed efficiency of grass-clover mixture (wilted silage, silage made of fresh material with addition of foDTiic acid, artifi­cially dried forage, pellets with varying portions of straw). The results obtained allow to draw the following conclusions:

As regards dry matter intake, digestibility, and feed efficiency, grass-dover for wilted silage should be wilted to give a OM content not exceeding 40 %.

Pelleting artificially dried grass-clover mix­ture and its use in mixed rations together with other separately pelleted components should be avoided.

The best feed efficiency is reached when dried grass-clover is converted …

The Influence Of Dried And Ensiled Grass On Rumen Fermen­Tation, J Voigt, B Piatkowski

IGC Proceedings (1977-2023)

Rumen-fistulated cows were used to study the influence of the forage preservation technique on rumen fermentation and holdup time of the feed in the rumen. Cocksfoot (Dactylis glomerata) preserved as wilted silage or dried green crop was fed in the following variants: wilted silage alone; wilted silage + sugar beet + protein supplement; dried green crop alone; dried green crop + sugar beet + protein supplement. As compared with dried green crop, the shares of true protein and sugar in wilted silage were reduced from 9.8 • to 6.4 '.'I􀉧 and from 7.7 to 1.8 %in DM, respectively. In comparison …

Changes In Feeding Value Of Preserved Grass And Legumes By The Action Of High Temperatures, R Prym, F Weissbach

IGC Proceedings (1977-2023)

High temperatures acting on grass and legumes during preservation and storage, cause nutrient digestibility to deteriorate. Protein digestibility is likely to be most strongly affected. Digest­ibility measurements were performed on sheep to estimate the extent of heat damage suffered by dried green forage and silages. Various laboratory methods were applied for record­ing. such damage. The detennination of the acid-detergent insoluble crude protein portion proved a very suitable approach.

Growth And Nitrogen Retention Of Lambs Fed Alfalfa Dehy­Drated At Different Temperatures, H K. Goering

IGC Proceedings (1977-2023)

Alfalfa was dried at four temperatures ranging from 60 to 180 °C in two experiments to evaluate the effect on composition, diet di­gestibility, and growth by lambs. In Experi­ment I, the alfalfa was supplemented with 0.6 % salt and pelleted. In Experiment 2, alfalfa was supplemented with 24.4 % starch, 18.5% straw, 6% cane molasses, 0.5% sodium phosphate, and 0.6 % salt so that total nitrogen intake was not in excess of the protein require­ment for growth of the lambs. Cell wall, acid­detergent fiber, lignin, acid-detergent insoluble nitrogen, and pepsin insoluble nitrogen in­creased in the alfalfa dried at 180 °C. …

Non-Mechanical Field Losses In Wilting Grasses As Influenced By Different Factors, G Rucker, O Knabe

IGC Proceedings (1977-2023)

When wilting grasses, non-mechanical field losses of different extent may occur. The main factors influencing the extent of losses were: water content at cutting time, drying rate, temperature, amount of rain, swath den­sity, and content of water-soluble carbohy­drates in the crop.

The Effect Of Mechanical, Thermal And Chemical Treatment On The Loss Of Water From Cut Leaves Of Grasses, Colin Edward Harris

IGC Proceedings (1977-2023)

Laboratory experiments have demonstrated that cut grass -leaves have a high resistance to water loss, probably largely due to the imper­meability of the surface cuticle to water vapour. This resistance can be reduced and drying rate increased by thermal and mechanical treatment, and by exposure to the vapour of boiling petroleum ether. The effectiveness of formic acid and tri-n-butyl phosphate suggests the possibility of using chemicals to increase the drying rate of grass crops cut for hay and dried in the field.

Measures For Increasing The Efficiency Of Hot-Air Drying Of Forage, Siegfried Prufer, Gerd Neubert

IGC Proceedings (1977-2023)

In the GDR, the drying of wilted green forage as well as of whole plants of cereals and grain maize considerably improves the effi­ciency of hot-air drying as a whole. The proc­essing of wilted crop and the inclusion of whole-plant drying in the drying pattern cause the throughput to increase by 30 to 50% and fuel consurnption per ton of dried crop to de­crease by up to 50 %, in comparison with drying of fresh green forage containing 15 to 18 % dry matter. Hot-air drying is particularly suitable for feed production along industrial lines. -Being but little dependent on …

Gdr Standard Plant For Producing Feed Pellets On Straw Basis, Gerheard Schmidt

IGC Proceedings (1977-2023)

Following the international trend, livestock production units are growing in size. Straw, a major feed reserve, must be effectively utilized to meet the growing roughage requirements, especially of ruminants. Therefore, in the GDR a standard feed pelleting plant (type GF A) was developed and put to commercial production. The various machines and equipment em­ployed in the different stages of the GFA pellet­ing technology are explained in detail. The use of that standard feed pelleting plant shows the advantages of processing straw for semi-finished and finished feeds.

The Efficiency Of Producing And Feeding Complete-Ration Feed Briquets Containing Forage Chop, G V. Blagoveshcheski, V M. Sokolov

IGC Proceedings (1977-2023)

Production of forage chop from a clover­timothy mixture is efficient when harvesting the forage between the shooting of clover (35 to 40 cm stand height) and mid-flowering. For high-temperature drying, each vegetative stage of the plants requires a clearly defined regime. When establishing formulas for com­plete-ration feed briquets containing clover­timoihy chop harvested before clover budding, the protein/carbohydrate ratio must be bal­anced by supplementing the ration with 30 p.c. barley meal and 29 p.c. straw; when the mix­ture was harvested during budding, phos­phorus supplementation (one p.c. monocal­cium phosphate) is necessary, whilst the mix­ture harvested during flowering has to be supplemented with …

The Production Of Dry Feeds From Straw And Green Forage In The Gdr, Fritz Berg

IGC Proceedings (1977-2023)

In the GDR, at present about 9% of the feed energy requirement of cattle is covered by dry feeds, above all mechanically processed and chemically treated straw as well as dried green forages. This share is expected to rise to 15 % in forthcoming years. On the basis of technological fundamentals devised by animal nutritionists, corresponding production processes are being developed and perfected. They allow to convert the feedstuffs into a physical and chemical form favourable to high intake; in addition, the feeding value of high-fibre feedstuffs is improved. In this way, the feedstuffs are fed in favourable com­bination as …

Evaluation And Determination Off Actors Defining The Length Of Thin-Stalked Green Forage Chop, Peter Szendro

IGC Proceedings (1977-2023)

A more exact analysis of the length distribution of chopped material from thin-stalked green forage crops provides more information for the further processing of this material and for comparing the quality of work of the different technologies. Material cut into longer and less homoge­neous chop with heavier destruction of the green plant particles shows properties more suitable for further processing than chop harvested with a self-propelled precision-chop forage harvester. In consideration of the special importance of the questions discussed it seems advisable to continue the experiments and to perform them under production conditions as well; the results thus obtained will …

Organization Of Wilted Silage Production Along Industrial Lines In The Selbelang Inter-Farm Cooperative Crop Produc­Tion Division, Hunter Watzke, Karl Bachmann

IGC Proceedings (1977-2023)

The production of high-quality wilted silages on the basis of highly efficient machines and facilities for harvesting and preservation in the Selbelang inter-farm cooperative crop pro­duction division (KAP) is determined by the use of industrial methods of production. Ob­servance of optimum spans for harvesting forage to be used for the production of wilted silage, and the full utilization of machinery and facilities at rising levels of labour pro­ductivity and declining cost are achieved by way of complex and shift employment of machines, facilities, and workers. The size of machine complexes and their performance are dependent on the shape, equipment and …

Possibilities Of Ensiling Meadow Grass With Different Water Content, Roman Moraczewski, Helena Jurkiewicz

IGC Proceedings (1977-2023)

The paper involves results of investigations into the influence of various methods of grass preservation, different cutting times, and dif­Jerent water contents on the nutrient and min­eral levels in the silage. These results show good possibilities of preserving meadow grass by ensiling. Silage fodder has higher contents of crude protein, crude fibre, crude fat, and ash constituents than are found in hay dried under optimum conditions.

Material And Processing Characteristics Of Grasses And Grass Silages, Manfred Muller, Georg Otto

IGC Proceedings (1977-2023)

Material and processing characteristics are essential initial values for planning of proce­dures in industrialized crop production. From the technological stages and process sequences from grass mowing to removing the silage, the following key operations can be derived: chop­ping,. compressing, storing, and removing. For adequate planning of procedures it is necessary to determine the quantitative relations between the essential factors: chopper throughput, pro­portion of short chop, crude fibre content, and relative final density. A relation suitable for practical application and providing sufficient accuracy is established for estimating the mean dry matter content of a trailer load. If high­quality silage is to …

Comparison Of Three Techniques Of Forage Conservation, Tereza Kotapska, Tadeusz Olszewski

IGC Proceedings (1977-2023)

At the Instytut Mechanizacji i Elektryfikacji Rolnictwa technological trials have been per­formed on green forage conservation under plastic sheeting using round formers from the Italian manufacturers Frigieri, a silage press from the French firm Kuhn, and portable seg­ments of Polish production for the erection clamp silos. The trials covered the operating quality of the equipment and the evaluation of silage quality. During the trials, the performance of the equipment on erecting the silos and specific labour expenditure were established. In addi­tion, an economic rating was made of the ensiling process and of the general suitability of the above methods for …

Losses And Stability Of Silage In Dependence On The Degree Of Air Influence, G Weise, H Rettig, G Suckow

IGC Proceedings (1977-2023)

On the basis of model concepts of physical gas exchange, a method has been developed for studying the complex relations existing be­tween the parameters indicating ensilability and the specific local conditions for silage making (degree of anaerobiosis). Conclusions are drawn as to quantitative relations between the depth of the peripheral layers of a silage stock that are endangered by air, the initial density of the silage material, and the sealing of the silage top during the filling and storage periods. Therefrom, certain thresh­olds can be derived for minimum filling height per day as depending on the initial density of the …

Factors Influencing The Formation Of Effluent In Forage Ensiling, G Peters, F Weissbach

IGC Proceedings (1977-2023)

The amount of effluent formed in ensiling forage crops depends, above all, on the dry matter content of the initial material, on the pressure exerted on the feed stock, and on the kind of crop ensiled. Expected values of effluent a­mount were derived from model experiments and calculations. Adequate wilting of suitable forage crops will allow to reduce or prevent effluent formation. The degree of wilting re­quired depends on the height of the feed stock and on the kind of silo used. The limit of 30 % DM in initial material, so far generally accepted for effluent formation, only applies …

Wilted Silage Production For The Supply Of Large Cattle Populations, Wilhelm Schwandt

IGC Proceedings (1977-2023)

For supplying large cattle populations with high-quality roughage it is necessary to make available big forage batches of good and large­ly uniform quality. From 4,675 hectares of seed­ed grassland, the ZBE Pflanzenproduktion Ferdinandshof(Ferdinandshofinter-farmestab­lishment for crop production) every year pro­duce in good quality more than 80,000 tons of wilted silage. The material and technical basis of this forage production along industrial lines consists of powerful machine systems that are operated in multi-machine complexes, the oper­ators doing shift work.

Fundamentals Of Technique For The Employment Of Formic Acid In Ensiling Of Green Forage, O Knabe, E Muller

IGC Proceedings (1977-2023)

A model was used to work out fundamentals of technique for the employment of formic acid in ensiling of wilted green· forage under industry-like conditions of production. From the parameters: result of preservation, ex­tent of dry matter losses, costs, and profit, the optimum length of the wilting phase in the field and the usefulness of combining the ensil­ing of wilted green forage with the employment of formic acid have been determined. The following practice is recommended for optimum planning of the technique: field curing of green forage for two days followed by preservation either as wilted silage or with admixture …