Agricultural Science Commons^™

Hop Cone Drying For The Small Grower: Temperature And Airflow Considerations, Stacy A. Adams, David M. Mabie, Michael F. Kocher, David Jones

Department of Agronomy and Horticulture: Faculty Publications

Small hop growers without nearby processors for cone stripping and drying must attempt to do so on their own farm. Challenges exist for self-built drying systems, including drying capacity, processing speed, airflow direction, and maintaining quality during drying. Research-based recommendations are given for optimal temperature, sizing of drying vessel, maximum cone depth, and influences associated with airflow on processing uniformity and cone quality are presented.

Evaluation Of Winter Cereal Cover Crops Across Nitrogen Management Strategies In No-Till Corn Production, Robert Nalley

Theses and Dissertations--Plant and Soil Sciences

Rye (Secale cereale L.) is the most popular winter cereal cover crop utilized before corn, but wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) may provide a comparable value due to their similar fibrous root systems. Despite the benefits associated with winter cereal cover crops, drawbacks are possible for the subsequent corn crop. A field study was conducted with three site-years in Kentucky to measure the impact of the three winter cereals across nitrogen (N) management strategies. Wheat produced the most biomass compared with barley or rye cover crops. Wheat and rye needed approximately 100 more …

Identifying Physiological, Morphological, And Genetic Drivers Of Key Intermediary Phenotypic Traits Associated With Stalk Lodging Resistance Within Genetically Diverse Maize Germplasm And Sorghum, Norbert Bokros

Theses and Dissertations--Plant and Soil Sciences

Maize stalk lodging reduces grain yields due to the permanent breakage or deformation of stalk tissue before grain harvest. To reveal new insights into the complex problem of maize stalk lodging, this dissertation will examine three primary objectives. First, the direct, diurnal influence of turgor pressure will be shown to have only marginal effects on stalk bending strength, a key trait associated with stalk lodging resistance. Up to a dozen individual stalks, grown to physiological maturity within the same field, were tested using a DARLING testing device. In parallel, stalk turgor status as measured by leaf water potential and turgor …

The Effect Of Spring And Winter Killed Cover Crops On Soil Physical Properties And Soil Organic Carbon, Danielle Doering

Theses and Dissertations--Plant and Soil Sciences

Maintaining soil organic carbon (SOC) and healthy soil physical structure in agroecosystems is crucial to sustainable production. To assess medium term impacts of cover crops on soil health in the top 90 cm, we conducted a field experiment in central Kentucky with varying levels of winter cover: spring and winter kill cover crops, weedy and bare winter fallows. After eight years of cover crop use, some soil physical properties improved: 35% greater mean weight aggregate diameter at 0-30 cm with spring kill covers and 5.2% more C held within large aggregates for both cover crop treatments compared to winter fallow. …

Development And Evaluation Of A Retrofittable Variable Rate Applicator Controller, Ahmed Abdalla

Electronic Theses and Dissertations

The need to optimize resource utilization while increasing crop productivity is paramount. This research proposes a Low-cost Retrofittable Variable Rate Applicator Controller (VRAC) that aims to leverage the adoption of Variable Rate Technologies. The controller operates via the Raspberry Pi platform, a Global Positioning System (GPS), a stepper motor drive, and an anti-slip wheel encoder. The VRAC allows precise, on-the-fly control of variable-rate application of farming inputs. It utilizes GPS with 10 cm accuracy to pinpoint geographic coordinates in real-time. A wheel encoder measures traveling speed with a slip-resistant wheel design for precise RPM readings. The Raspberry processes the data, …

Competition Between Bradyrhizobium Strains For Soybean Nodulation, Lilia Ernestina Montanez Hernandez

Electronic Theses and Dissertations

Biological Nitrogen Fixation (BNF) has surged as a natural strategy to provide available nitrogen to crops by taking advantage of diazotrophs, microorganisms that can reduce atmospheric nitrogen to ammonia. Soybean, a major crop, greatly benefits from BNF by forming endosymbiotic relationships with rhizobacteria from the genus Bradyrhizobium, which culminates in the formation of specialized organs called nodules, where nitrogen fixation occurs. This is known as Symbiotic Nitrogen Fixation (SNF). Inoculation of soybean fields with high nitrogen fixing Bradyrhizobium strains to stimulate SNF is being used as a strategy to increase crop productivity and nitrogen content. However, in North America, SNF …

Early Season Biomass And Weather Enable Robust Cereal Rye Cover Crop Biomass Predictions, Alexandra M. Huddell, Brian Needleman, Eugene P. Law, Victoria J. Ackroyd, Muthukumar V. Bagavathiannan, Kevin Bradley, Adam S. Davis, Jeffrey A. Evans, Wesley Jay Everman, Michael Flessner, Nicholas Jordan, Lauren M. Schwartz-Lazaro, Ramon G. Leon, John L. Lindquist, Jason K. Norsworthy, Lovreet S. Shergill, Mark Vangessel, Steven B. Mirsky

Department of Agronomy and Horticulture: Faculty Publications

Farmers need accurate estimates of winter cover crop biomass to make informed decisions on termination timing or to estimate potential release of nitrogen from cover crop residues to subsequent cash crops. Utilizing data from an extensive experiment across 11 states from 2016 to 2020, this study explores the most reliable predictors for determining cereal rye cover crop biomass at the time of termination. Our findings demonstrate a strong relationship between early-season and late-season cover crop biomass. Employing a random forest model, we predicted late-season cereal rye biomass with a margin of error of approximately 1,000 kg ha⁻¹ based on …

Integrating Early Season Clover Cover Crops As A Living Mulch In Broccoli And Transitional Organic Winter Squash Production In Eastern South Dakota, Alexis Rose Barnes

Electronic Theses and Dissertations

Managing weeds, improving soil health, and reducing the use of plastic mulch continue to be priorities for South Dakota vegetable farmers. Farmers have expressed an interest in integrating cover crops into their farm systems. Clover cover crops used as a living mulch within and along cash crop rows may aid in weed suppression, nitrogen fixation, and prevent soil erosion. However, prior research has shown challenges of incorporating living mulch due to yield decreases. Research conducted in 2022 and 2023 in eastern South Dakota investigated the effects of four clover and four in-row soil management treatments on broccoli and organic winter …

Insect Frass Fertilizer As A Regenerative Input For Improved Biological Nitrogen Fixation And Sustainable Bush Bean Production, Agnes Chepkorir, Dennis Beesigamukama, Harun I. Gitari, Shaphan Y. Chia, Sevgan Subramanian, Sunday Ekesi, Birachi Eliud Abucheli, Jean Claude Rubyogo, Theodore Zahariadis, Gina Athanasiou, Aikaterini Zachariadi, Vasileios Zachariadis, Abdou Tenkouano, Chrysantus M. Tanga

All Peer-Reviewed Publications

Bush bean (Phaseolus vulgaris L.) production is undermined by soil degradation and low biological nitrogen fixation (BNF) capacity. This study evaluated the effect of black soldier fly frass fertilizer (BSFFF) on bush bean growth, yield, nutrient uptake, BNF, and profitability, in comparison with commercial organic fertilizer (Phymyx, Phytomedia International Ltd., Kiambu, Kenya), synthetic fertilizer (NPK), and rhizobia inoculant (Biofix, MEA Fertilizers, Nairobi, Kenya). The organic fertilizers were applied at rates of 0, 15, 30, and 45 kg N ha−1 while the NPK was applied at 40 kg N ha−1, 46 kg P ha−1, and 60 kg K ha−1. The fertilizers …

Comparative Microbiome Diversity In Root-Nodules Of Three Desmodium Species Used In Push-Pull Cropping System, Isack H. Adan, George Ochieng Asudi, Saliou Niassy, Abdul A. Jalloh, Johnstone Mutiso Mutua, Frank Chidawanyika, Fathiya Khamis, Zeyaur Khan, Sevgan Subramanian, Thomas Dubois, Daniel Munyao Mutyambai

All Peer-Reviewed Publications

Background: Desmodium species used as intercrops in push-pull cropping systems are known to repel insect-pests, suppress Striga species weeds, and shift soil microbiome. However, the mechanisms through which Desmodium species impact the soil microbiome, either through its root exudates, changes in soil nutrition, or shading microbes from its nodules into the rhizosphere, are less understood. Here, we investigated the diversity of root-nodule microbial communities of three Desmodium species- Desmodium uncinatum (SLD), Desmodium intortum (GLD), and Desmodium incanum (AID) which are currently used in smallholder maize push-pull technology (PPT). Methods: Desmodium species root-nodule samples were collected from selected smallholder farms in …

Chitin-Enriched Insect Frass Fertilizer As A Biorational Alternative For Root-Knot Nematode (Meloidogyne Incognita) Management, James Kisaakye, Dennis Beesigamukama, Solveig Haukeland, Sevgan Subramanian, Paul K. Thiongo, Segenet Kelemu, Chrysantus M. Tanga

All Peer-Reviewed Publications

Root-knot nematodes (Meloidogyne spp.) are serious pests of most food crops, causing up to 100% yield loss. Nevertheless, commercial nematicides are costly and harmful to the environment. While the nematicidal potential of crustacean and synthetic chitin has been demonstrated globally, research on the potential of insect-derived chitin for nematode control has received limited attention. Here, seven chitin-fortified black soldier fly frass fertilizer extracts (chFE) were assessed for their suppressiveness of Meloidogyne incognita and impacts on spinach growth in comparison with a commercial nematicide using in vitro and in vivo bioassays. The performance of chFE and control treatments was assessed by …

The Effect Of Biochar From Plant Materials On Agricultural Acid Sulfate Soil: A Laboratory Incubation, Syazwan Sulaiman, Namasivayam Navaranjan, Guillermo Hernandez-Ramirez, Zohrah Sulaiman, Kathereen Liew

ASEAN Journal on Science and Technology for Development

The scarcity of suitable arable land has led to the development of acid sulfate soil for cultivation. The major problems of acid sulfate soil are the inherent low pH and available phosphorus (P) as well as the mobilization of toxic elements such as aluminium (Al) and iron (Fe), rendering the soil unfavourable for crop production. The present work aimed to evaluate the effect of biochar from plant materials on the selected parameters of acid sulfate soil in a laboratory incubation, with unamended control and dolomite treatment soils for comparison. The application of biochar significantly increased (P < 0.05) soil pH by 0.4-0.6 units as well as the soil available P by 13.1 mg kg-1 relative to the control. The soil exchangeable Al was significantly reduced (by 2.4 cmol kg-1 when compared with the control treatment. The dolomite treatment was superior relative to biochar application in increasing soil pH and decreasing Al. The dolomite application, however, was inferior to biochar treatment in increasing soil available P. Moreover, no favourable change was observed in available Fe with the applications of either biochar or lime. These results indicated that biochar has the potential for the amelioration of acid sulfate soil, especially in increasing available P. Further studies should explore the effectiveness of biochar and lime co-application in altering a wider range of soil chemical parameters to inform management options of acid sulfate soil for cultivation.

Integrating Vegetables In Push-Pull Technology: Gendered Preferences Of Smallholder Farmers In Western Kenya, F. O. Ouya, J. O. Pittchar, F. Chidawanyika, Z. R. Khan

All Peer-Reviewed Publications

Transformative rural smallholder agriculture addressing biophysical constraints requires farmer-led innovations for increased technology adoption. Following the need to further intensify the cereal push-pull technology (PPT) for pest and weed control through integration with vegetables, we conducted surveys to determine suitable vegetables across three different counties in Kenya namely Homabay, Siaya, and Trans-Nzoia. Farming in these areas is predominantly maize based and introducing vegetables to the system will improve household food and nutritional security, together with income. A systematic random sampling method was used to sample a total of 124 smallholder farmers who were interviewed during field days where farmer awareness …

Plant-Parasitic Nematodes Associated With Maize, And Their Relationship With Soil Properties In Southern And Southwestern Ethiopia, Abebe W. Aseffa, Beira H. Meressa, Tadele Tefera, Kristina K. Green, Peter Anderson, Esayas Mendesil

All Peer-Reviewed Publications

Maize is an important cereal crop in sub-Saharan Africa (SSA). Plant-parasitic nematodes significantly impact maize production. However, research on maize nematodes in SSA is limited. The current study aimed to assess the occurrences and densities of nematodes associated with maize and to assess the correlation of some soil physicochemical properties with nematodes in southern and southwestern Ethiopia. One hundred and eighty-six soil and root samples were collected from 62 maize fields (31 from Hawassa Zuria and 31 from Mana districts). Eleven plant-parasitic nematode genera were identified. The most important genera of plant-parasitic nematodes identified were Meloidogyne and Pratylenchus, followed by …

Characterisation Of ‘Giant’ Cysts Of The Potato Cyst Nematode, Globodera Rostochiensis, Present In Potato Fields In Kenya, James A. Price, Kelsey Hunt, Newton Nyagah, Calvince Orage, Onesmus Mwaura, Solveig Haukeland, Danny Coyne, John T. Jones

All Peer-Reviewed Publications

Potato production in East Africa is seriously impacted by the potato cyst nematode (PCN), Globodera rostochiensis, where it has been recorded in at least three countries. In Kenya, it is widespread in all major potato-growing regions, often at very high densities. Consecutive cropping of potato on the same land and a sub-tropical climate have influenced PCN biology. For example, unusually large cysts have been regularly recovered. We have analysed the biological properties of these ‘giant cysts’. The giant cysts contained more eggs than those recovered from UK fields. Egg size did not differ from UK populations and there was no …

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …

A Vision For A Food-Secure Future Through Permaculture, Jim Gale

Journal of Nonprofit Innovation

In response to the pressing challenges of food security, sustainability, and resilience, Food Forest Abundance, led by visionary CEO Jim Gale, emerges as a beacon for permaculture-based agriculture and community development. This editorial explores the organization's pivotal role in advocating for a future where individuals, families, and communities thrive through sustainable practices and localized food systems. Central to Food Forest Abundance mission is the conviction that permaculture principles can revolutionize our approach to food security, health, and wellness by uniting agricultural and community leaders.

The catalyst for this movement was the World Farmers Market Coalition report, revealing the tangible economic, …

Crop Dna Extraction With Lab-Made Magnetic Nanoparticles, Haichuan Wang, Xueqi Zhao, Li Tan, Junwei Zhu, David Hyten

Department of Agronomy and Horticulture: Faculty Publications

Molecular breeding methods, such as marker-assisted selection and genomic selection, require high-throughput and cost-effective methods for isolating genomic DNA from plants, specifically from crop tissue or seed with high polysaccharides, lipids, and proteins. A quick and inexpensive high-throughput method for isolating genomic DNA from seed and leaf tissue from multiple crops was tested with a DNA isolation method that combines CTAB extraction buffer and lab-made SA-coated magnetic nanoparticles. This method is capable of isolating quality genomic DNA from leaf tissue and seeds in less than 2 hours with fewer steps than a standard CTAB extraction method. The yield of the …

Correlation Analysis Between Agronomic Character And Yield Of Padjadjaran Maize Hybrids At Medium And High Population Densities, Yuyun Yuwariah, Qinthara Nail Haysa, Damara Bakti Muhammad, Dedi Ruswandi, Fiky Yulianto Wicaksono

Jurnal Kultivasi

Maize is a prospective food commodity that developed in Indonesia. The use of hybrid corn gives better yield than open-pollinated varieties. Spacing management in hybrid maize production can reduce competition between plants, so that the plant canopy and roots can grow optimally. This research aimed to compare the differences in the phenotypic performance of the agronomic characters of Padjadjaran maize hybrid, determine the dominant agronomic characteristics, and determine the correlation between the growth and yield characteristics at medium- and high-population densities. The experiment was carried out from December 2021 until May 2022 at Sanggar Penelitian, Latihan dan Pengembangan Pertanian (SPLPP) …

A Year Of Wins For Farmed Animals, Lewis Bollard

General – Farm Animal Issues

Although the European Union shelved its ambitious farmed animal welfare reforms, there were other “wins” for farmed animals in 2023. There were 130 new corporate pledges to eliminate cages for laying hens and the worst abuses of broiler chickens. So far, over 1,000 corporate pledges have been fully implemented, and 39% of American hens, 60% of European hens, and 80% of British hens are cage-free, up from 6%, 41%, and 48%, respectively, a decade ago. The US Supreme Court upheld California’s Proposition 12, which bans the sale of eggs, pork, and veal from caged animals and their offspring in California. …