Agronomy and Crop Sciences Commons^™

Hymenopteran Parasitoids Of Fall Armyworm (Spodoptera Frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)) In Australia, With The Description Of Five New Species In The Families Braconidae And Eulophidae, Erinn P. Fagan-Jeffries, Melina M. Miles, Tareva-Chine C. Atkin-Zaldivar, Andy G. Howe, Siva Subramaniam, Donna M. Chambers, Frezzel Praise J Tadle, Saleh Adnan, Verni Sivasubramaniam, Alice Woodward, Helen Spafford, Brian Thistleton

Biosecurity Research Articles

Fall armyworm, Spodoptera frugiperda (J.E. Smith) is an invasive pest of agricultural crops including sweet corn and maize. The moth was first recorded in Australia in January 2020 and is now considered established in most states and territories, and research is underway to develop management strategies. Extensive rearing of S. frugiperda larvae and eggs occurred from March 2020 to April 2023 to understand the parasitoid complex present in Australia and identify potential biological control agents. We report here on the hymenopteran parasitoids reared during this period, which were identified using a combination of morphology and COI DNA barcoding, and provide …

Investigating The Impact Of Climate Change On Evapotranspiration Using Modeling, Faten Waheed

Theses and Dissertations

The available water resources are at risk due to climate change and the increasing water demand. Evapotranspiration is a very important element in water cycle. Evapotranspiration is perceived as a linking mechanism between the surface of the land and the atmosphere. Therefore, investing appropriate approaches to estimate evapotranspiration and the implication of climate change on evapotranspiration and available water resources are of great importance for better water management and food security. Penman-Monteith (PM) equation is considered as one of the most widely used equation for estimating ETo. It is also one of the most complex energy balance equations requiring detailed …

Assessing The Use Of Regenerative Agriculture In California Almonds As Climate Change Resilience, Skyler M. Seamons

Master's Projects and Capstones

The agriculture sector is responsible for 10% of the United States’ greenhouse gas emissions. In turn, anthropogenic climate change threatens crops. With its Mediterranean climate, California is the country’s largest agricultural-producing state. Many California crops are at risk due to increasing temperatures and changed precipitation patterns. This paper investigates regenerative farming techniques as a tool to protect California crops from a changing climate. Almonds are used as a case study to analyze the soil management practices, finances, and policies underlying regenerative agriculture in California. A literature review and comparative analysis are used to compare regenerative and conventional soil management practices …

Adopting Yield-Improving Practices To Meet Maize Demand In Sub-Saharan Africa Without Cropland Expansion, Fernando Aramburu-Merlos, Fatima A. M. Tenorio, Nester Mashingaidze, Alex Sananka, Stephen Aston, Jonathan J. Ojeda, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Maize demand in Sub-Saharan Africa is expected to increase 2.3 times during the next 30 years driven by demographic and dietary changes. Over the past two decades, the area croppedwithmaize has expanded by 17million hectares in the region, with limited yield increase. Following this trend could potentially result in further maize cropland expansion and the need for imports to satisfy domestic demand. Here, we use data collected from 14,773 smallholder fields in the region to identify agronomic practices that can improve farm yield gains. We find that agronomic practices related to cultivar selection, and nutrient, pest, and crop management can …

The De-Domestication Of Ornithopus Sativus Brot. To Develop Cultivars With Physical Dormancy (Hardseed), Robert J. Harrison, Bradley J. Nutt, Ronald J. Yates, Belinda F. Hackney, John G. Howieson

Grain and Other Field Crops Research Articles

Ornithopus sativus Brot. (French serradella) is a forage legume that is well adapted to acidic coarse textured soils (sands) which are characterized by poor nutrition and an inability to retain water. During the process of domestication of O. sativus, there was an unintentional loss of seed physical dormancy (PY) thus compromising its self-regeneration after a cropping interval. Through mass screening of seed, we identified for the first time that heritable sources of PY exist in three populations of O. sativus. This rare genetic material was then incorporated into suitable genetic backgrounds of differing maturity through targeted hybridization. We demonstrated …

Evaluating The Yield Of Surviving Plants From Early-Season Hail Damage In Corn: A Field Survey, I. P. Lisboa, Christopher A. Proctor, R W. Elmore, A. J. Mcmechan, N. D. Mueller, J. Wilson, G. Zobeck, Aaron Nygren, A. Bastidas, Osler Ortez

Department of Agronomy and Horticulture: Faculty Publications

Economic losses due to hailstorms acrossUS corn fields occur every year.Hailstorms result in leaf defoliation, decreasing photosynthetic area and impairing carbon assimilation and crop yield for all corn (Zea mays L.) development stages. However, more attention is often given to stand reductions rather than damage to stems or leaf defoliation. During the 2014 growing season, a natural hail event affected many areas of eastern Nebraska. Twelve affected corn fields were surveyed and included in this study. An injury score scale (1–5) was developed based on various injury and severity levels before the V6 (6-leaf corn growth stage) (six-collared leaves). …

Agroecology And Soil Stewardship: Values And Techniques Of Smallholder Farmers In Bernalillo County, Stephanie Olivas

Geography ETDs

Agrarian movements around the world use agroecology to build sovereignty and steward dynamic ecosystems. Research has shown that agroecological farmers steward more resilient crops, more resilient soil biomes, and greater biodiversity than conventional agriculture. GIS and remote sensing offer many tools to detect the impacts of these farmers on the environment, but it is less clear how such technologies fit into agroecological goals. This study asks: what values, experiences and knowledge do smallholder producers in Bernalillo County embody in their soil stewardship practices? Also, what experience or knowledge do smallholder producers in Bernalillo County have about remote sensing, and would …

Natural Variation In Lonely Guy-Like 1 Regulates Rice Grain Weight Under Warmer Night Conditions, Jaspreet Sandhu, Larissa Irvin, Anil Kumar Chandaran, Shohei Oguro, Puneet Paul, Balpreet Dhatt, Waseem Hussain, Shannon S. Cunningham, Cherryl O. Quinones, Argelia Lorence, Maria Arlene Adviento-Borbe, Paul E. Staswick, Gota Morota, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Global nighttime temperatures are rising at twice the rate of daytime temperatures and pose a challenge for rice (Oryza sativa) production. High nighttime temperature (HNT) stress affects rice yield by reducing grain weight, size, and fertility. Although the genes associated with these yield parameters have been identified and characterized under normal temperatures, the genetic basis of grain weight regulation under HNT stress remains less explored. We examined the natural variation for rice single grain weight (SGW) under HNT stress imposed during grain development. A genome-wide association analysis identified several loci associated with grain weight under HNT stress. A …

Identifying High-Value Tactical Livestock Decisions On A Mixed Enterprise Farm In A Variable Environment, Michael Young, John Young, Ross S. Kingwell, Philip E. Vercoe

Animal production and livestock research articles

Context

Australia is renowned for its climate variation, featuring years with drought and years with floods, which result in significant production and profit variability. Accordingly, to maximise profitability, dryland farming systems need to be dynamically managed in response to unfolding weather conditions.

Aims

The aim of this study is to identify and quantify optimal tactical livestock management for different weather-years.

Methods

This study employed a whole-farm optimisation model to analyse a representative mixed enterprise farm located in the Great Southern region of Western Australia. Using this model, we investigated the economic significance of five key livestock management tactics. These included …

Annual Pasture Quantity And Quality In South West Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Animal production and livestock factsheets

The productivity of sheep is largely governed by the amount of pasture they eat and this is influenced by the quantity of the pasture on offer and its quality. Assessing pasture quantity and quality throughout the growing season gives managers the information they need to manage animal performance and pasture condition.

The Department of Primary Industries and Regional Development provides this information for farmers to help improve the productivity and profitability of the livestock industry in Western Australia.

On-Farm Nitrogen And Irrigation Management Strategies To Protect Groundwater Quality In The Bazile Groundwater Management Area, Arshdeep Singh

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

Increasing groundwater nitrate (NO₃-N) contamination has raised significant environmental and health concerns in the irrigated sandy soils of Nebraska. Four studies were conducted to evaluate the impact the impact of 1) static (NE Yield Goal) vs. dynamic nitrogen (N) recommendations tools (Maize-N, Canopy Reflectance Sensing, Granular, and Adapt-N), 2) three N (optimum, suboptimum, and low) and irrigation rates (farmer’s full irrigation (FIT), 80% FIT, and 60% FIT), 3) conventional N sources vs. enhanced efficiency fertilizers (EEFs), and 4) multiple N splits (2, 3, 4, and 5-N splits) on agronomic (maize yield), environmental (NO3-N leaching), and economic returns (return …

Establishment Of Wildflower Islands To Enhance Roadside Health, Ecological Value, And Aesthetics, Jackson Ebbers

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

Roadsides provide an abundant opportunity to increase connectivity of fragmented landscapes with diminishing floral resources for pollinating insects. The ecological value of these sites is often overlooked as quality habitat for pollinators, particularly monarch butterflies, which have been experiencing severe declines due to loss of habitat and loss of milkweeds that provide food for their larvae. Land managers across the nation are realizing the potential of roadsides to provide high quality floral resources for the benefit of insects and other wildlife. Current wildflower seed mixes used by state transportation departments are often low diversity and may only be implemented following …

Using Annual Forages To Replace Declining Cool-Season Grass Pasture Availability, Jonathon Matthew Jenkins

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

As land area in grain crop production increases in the US Midwest, perennial pasture availability decreases but the demand increases. Matching the seasonal growth patterns of C₃ and C₄ plant species to grow forages that are complementary allows producers to fill production gaps in otherwise monoculture systems and possibly increase overall productivity. One way to fill the forage production gap of C₃ grass dominated pastures is by producing a warm-season, annual forage in a separate field. However, with continual reductions in land availability, this may not be an option. Using two studies, our objectives were to improve …

Impact Of Early-Season Postemergence Co-Applications Of Foliar And Residual Herbicides On Crop Injury, Growth, And Yield In 2,4-D- And Dicamba-Tolerant Cotton (Gossypium Hirsutum L.), Logan N. Vallee

LSU Master's Theses

Studies were conducted in 2021 through 2023 at the LSU AgCenter Dean Lee Research and Extension Center near Alexandria, LA to determine the sensitivity of 2,4-D- or dicamba- tolerant cotton (Gossypium hirsutum L.) to an early season application of a Group 15 and foliar-only herbicides. Both studies were randomized complete block designs with a two-factorial arrangement of treatments with four replications. In the dicamba-tolerant cotton study, Factor A consisted of no foliar-herbicide, dicamba alone, glyphosate alone, or dicamba plus glyphosate. Factor B consisted of either no Group 15 residual herbicide, acetochlor, or S-metolachlor. In the 2,4-D- tolerant cotton …

Evaluation Of Late Season Potassium Applications To Arkansas Soybean, Carrie Ortel

Graduate Theses and Dissertations

Potassium (K) deficiency is one of the most important yield limiting factors in Arkansas soybean (Glycine max (L.) Merr.) production, although there are recently improved diagnostic and management opportunities available. However, several questions regarding the successful implementation of in-season K management in soybean production remain. Therefore, the research objectives were to (a) delineate the relationship between drought stress and K deficiency on soybean vigor, (b) identify the spatial dependencies of leaf-K concentrations at the production scale, (c) develop a leaf sampling protocol, (d) calibrate the fertilizer-K rate needed to correct varying levels of K deficiency at 15, 30, and …

Evaluation Of Essential Oils And Their Major Components For Disease Resistance, Serkan Tokgöz

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Essential oils (EOs) are natural hydrophobic compounds, which are highly complex, typically comprising 20 to 60 constituents, with two or three main components making up 20% to 95% of their composition, alongside other minor constituents. Research has firmly established the potent antibacterial and antifungal properties of EOs and their primary components. To assess their efficacy, one EO, nutmeg oil, and seven main components, including safrole, toscanol, safraleine, cinnamaldehyde, carvacrol, carvone, and thymol, were tested against four economically significant fungal pathogens (Alternaria solani, Fusarium graminearum, Rhizoctonia solani, and Sclerotiorum sclerotiorum), one oomycete pathogen (Phytium ultimum …

Irt-Based Irrigation Scheduling And Dry Bean Crop Water Productivity Under Different Irrigation Scenarios In The Nebraska High Plains, Angie Gradiz

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Irrigation plays a critical role for crop production in western Nebraska of the United States, where crop evapotranspiration often exceeds in-season precipitation. This study investigated the impacts of different irrigation treatments on yield and key physiological parameters of dry edible beans grown in semi-arid western Nebraska during the 2022-2023 growing seasons. Seven irrigation levels (0%, 25%, 50%, 75%, 100%, 125%, 150%) of the fully irrigated treatment (FIT), were applied using a Variable Rate Irrigation (VRI) Linear-Move Sprinkler System. Additionally, an eighth treatment was scheduled based on measurement from infrared radiometry thermometers (IRT) to evaluate the performance of the two-source energy …

Effective Furrow Sowing For Water Repellent Soils, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Furrow sowing creates micro-relief, small ridges, and furrows into which water can be harvested. Sloping water repellent surfaces induce run-off, which collects at the base of the sown furrow, enhancing water entry through increased hydraulic pressure.

Additional Cocopeat And Coconut Water Improves The Seedling Growth Of Robusta Coffee, Intan Ratna Dewi Anjarsari, Anita Febiola, Mira Ariyanti, Ifwarisan Defri

Jurnal Kultivasi

Robusta coffee production can be sucessed by using high-quality seedlings that have good growth performance. One of several keys to success in seedling production is the choosing best planting medium and providing exogenous growth regulators. These include using cocopeat planting media and giving coconut water. This research aims to determine whether using cocopeat planting media and providing coconut water can increase the growth of robusta coffee seedlings. The experiment used a randomized complete group design with six treatments and four replications; each experimental unit consisted of three robusta coffee seedlings. The six tested treatments were control (topsoil 100%); cocopeat 50% …

Linking Reactive Nitrogen Species Within The Vadose Zone With Surface Irrigation, Kaitlyn Richards

Honors Program: Senior Projects (Public)

This study investigated the relationship between irrigation methods and the mobilization of nitrogen in the vadose zone, focusing on soil properties, water dynamics, and nitrogen species distribution. Data collected from dryland and pivot-irrigated soil cores reveal distinct patterns in water content, bulk density, soil texture, pH, conductivity, and nitrogen concentrations. Results indicated that water content has a major influence in nitrogen availability and microbial activity. Nitrate-N and ammonium-N concentrations varied between dryland and pivot soils, with notable disparities observed. In dryland soils, nitrate-N concentrations varied widely across depth intervals, with notable accumulation in deeper layers, while ammonium-N concentrations exhibited a …

Overexpression Of Msdreb1c Modulates Growth And Improves Forage Quality In Tetraploid Alfalfa (Medicago Sativa L.), Yangyang Zhang, Zhen Wang, Fan Zhang, Xue Wang, Yajing Li, Ruicai Long, Mingna Li, Xianyang Li, Quanzhen Wang, Qingchuan Yang, Junmei Kang

Department of Agronomy and Horticulture: Faculty Publications

DREB has been reported to be involved in plant growth and response to environmental factors. However, the function of DREB in growth and development has not been elucidated in alfalfa (Medicago sativa L.), a perennial tetraploid forage cultivated worldwide. In this study, an ortholog of MtDREB1C was characterized from alfalfa and named MsDREB1C accordingly. MsDREB1C was significantly induced by abiotic stress. The transcription factor MsDREB1C resided in the nucleus and had self-transactivation activity. The MsDREB1C overexpression (OE) alfalfa displayed growth retardation under both long-day and short-day conditions, which was supported by decreased MsGA20ox and upregulated MsGA2ox in the OE …

Evaluating Consistency Across Multiple Neospectra (Compact Fourier Transform Near-Infrared) Spectrometers For Estimating Common Soil Properties, Sadia M. Mitu, Colleen Smith, Jonathan Sanderman, Richard R. Ferguson, Keith Shepherd, Yufeng Ge

Department of Agronomy and Horticulture: Faculty Publications

Rapid and cost-effective techniques for soil analysis are essential to guide sustainable land management and production agriculture. This study aimed at evaluating the performance and consistency of portable handheld Fourier-transform near-infrared spectrometers and the NeoSpectra scanners in estimating 12 common soil physical and chemical properties including pH; organic carbon (OC); inorganic carbon (IC); total nitrogen (TN); cation exchange capacity (CEC); clay, silt, and sand fractions; and exchangeable potassium (K), phosphorus (P), calcium (Ca), and magnesium (Mg). A diverse set of samples (n = 600) were retrieved from a national-scale soil archive of the Kellogg Soil Survey Laboratory of USDA-NRCS …

Accurate Measurement Of Field Size Is Essential For Analysis Of Smallholder Survey Data, Rica Joy Flor, Shen Yuan, Gonzalo Rizzo, Fahmuddin Agus, Anny Ruth P. Pame, Akhara Ouk, Rathmuny Then, Sokheng Keo, Virender Kumar, Particio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Context: Agronomic surveys play a vital role in identifying on-farm yield constraints and opportunities to increase productivity, input-use efficiency, and farmer profit. These surveys typically rely on farmer-reported data, where crop yield and applied inputs per hectare are estimated based on farmer-reported total harvested output and applied inputs per field and associated field size. At question is how accurate field size is, which is vital in the case of smallholders as small inaccuracies can lead to large biases in estimated yield and inputs.

Objectives: The goals of this study are to assess current approaches to determine field size …

Phenotypic Diversity For Morpho-Agronomic Traits In The Us Proso Millet (Panicum Miliaceum L.) Core Collection, Santosh G. Rajput, Rituraj Khound, Dipak K. Santra

Department of Agronomy and Horticulture: Faculty Publications

Proso millet (Panicum miliaceum L.) is a short-season annual crop known for high water-use efficiency and drought tolerance. The low water requirement makes this ancient grain an excellent rotational crop for the winter wheat-based dryland cropping system in theHigh Plains of theUnited States. The genetic base of the commonly grown US cultivars is very narrow. Assessment of proso millet germplasm for agronomic traits is essential for its efficient utilization in the genetic improvement of this crop. The objectives of this study were to (1) characterize the US proso millet germplasm based on nine important morpho-agronomic traits and (2) classify …

Influence Of Low-Level Condensed Tannins Concentrations In Temperate Forages On Sheep Performace, F Montossi, F Liu, J Hodgson, S T. Morris, T N. Barry, D F. Risso

IGC Proceedings (1977-2023)

Results from a series of six comparative lamb grazing trials with temperate forages are summarised, and compared with results from the literature. Condensed tannin (CT) concentrations in the diet ranged from 0.12% to 0.47% on a dry matter (DM) basis. Values were generally similar for Yorkshire fog (Holcus lanatus), perennial ryegrass (Lolium perenne) and annual ryegrass (L. multiflorum), each grown with white clover (Trifolium repens), in similar circumstances. Concentrations for tall fescue (Festuca arundinacea)/white clover pastures were relatively low, but may have been artefacts. Drenching with polyethylene glycol (PEG) to bind …

Tannin Contents Of Some Indigenous Browse Plants Of Botswana, A A. Aganga, C M. Tsopito, K M. Morake

IGC Proceedings (1977-2023)

A study was carried out to evaluate the tannin content and crude protein degradation of leaves and twigs from indigenous browsable trees which provide feed for grazing livestock on natural rangelands of Botswana. These browses include the families Leguminosae (Acacias), Capparidaceae (Boscias), Combretaceae (Combretum) and Tiliaceae (Grewias). These were found to be of good nutritive value, with the leaves having a high content of crude protein (9 - 16%) and a wide range of dry matter digestibility (37 - 69.82%). The correlation between crude protein disappearance and tannin content was found to be negative (-0.582) and significant (P<0.05).

Effect Of Tannin In Animal Diet On Nitrification Rate Of Pasture Soil Under Dung Patches, J R. Crush

IGC Proceedings (1977-2023)

The rate of formation of nitrate and ammonium in the soil under dung patches was compared for dung from animals fed either ryegrass (Lolium perenne)/white clover (Trifolium repens) or ryegrass/Lotus pedunculatus forage. Tannin derived from the Lotus did not inhibit ammonification in the soil under dung but nitrate formation was strongly inhibited. The results support the theory that polyphenolics may bind to nitrite in acid soils and cause immobilisation of mineral nitrogen. Apart from their effect of reducing the proportion of dietary nitrogen excreted in urine, tannins in animal diets may make a further contribution to …

Condensed Tannins In Tropical Legumes: Concentration, Astringency And Effects On The Nutrition Of Ruminants, R Barahona, C E. Lascano, R C. Cochran, J L. Morrill, E C. Titgemeyer

IGC Proceedings (1977-2023)

A feeding trial was carried out to determine the effect of extractable condensed tannins (ECT) concentration and tannin astringency in tropical legumes on nitrogen (N) digestion by sheep. Test legumes were Desmodium ovalifolium (Do) and Flemingia macrophylla (Fm) which had similar concentrations of Extractable CT (9% DM) but tannins with different degree of astringency (Do, 0.6 and Fm, 0.3 g protein bound/g of ECT). Chopped sun-dried forage of each legume was sprayed with either water (control) or polyethylene glycol (PEG, 3.5% DM) to reduce ECT and fed to 8 sheep with ruminal and duodenal canulas arranged in a replicated 4 …

Effect Of Condensed Tannin In Lotus Corniculatus And Lotus Pedunculatus On Digestion Of Rubisco In The Rumen, W C. Mcnabb, R J. Aerts, A Brand, J S. Peters, Y L. Foo, G C. Waghorn

IGC Proceedings (1977-2023)

The in vitro precipitation of ribulose-1,5-bisphosphate carboxylase (Rubisco) by condensed tannin (CT) extracted from Lotus corniculatus and Lotus pedunculatus and the effect of these CT on the in vitro rumen degradation of Rubisco was used to compare the reactivity of these CT. The chemical structure of CT from Lotus corniculatus was homogenous with epicatechin stereochemistry and mostly procyanidin units. The CT from Lotus pedunculatus was heterogenous with mostly prodelphinidin units. The amount of CT required to precipitate all the Rubisco when total soluble leaf protein was incubated with CT from Lotus corniculatus and Lotus pedunculatus was similar. Although CT from …

Nitrogen And Fiber Digestion In Sheep Fed Fresh-Frozen And Field-Dried High And Low Tannin Sericea Lespedeza, T H. Terrill, W R. Windham, C S. Hoveland, H E. Amos, B Kouakou, S Gelaye

IGC Proceedings (1977-2023)

Field-drying reduces extractable condensed tannin (CT) of sericea lespedeza [Lespedeza cuneata (Dum-Cours) G. Don], but effects on specific bound and unbound forms of CT and the relationship to protein and fiber digestion in ruminants are unclear. Intake and digestibility of fresh-frozen and field-dried high- and low-tannin sericea were investigated in a feeding trial with sheep (Ovis spp.). Field-drying had no effect on crude protein (CP) and fiber content of sericea, but shifted CT from extractable to bound forms. Digestion coefficients for CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were lower for high-tannin sericea than the low-tannin …