Agronomy and Crop Sciences Commons^™

Radiation Use Efficiency Of Ryegrass: Determination With Non Cumulative Data, R. Lambert, A. Peeters

IGC Proceedings (1977-2023)

The growth of a crop is generally described as biomass accumulation per unit time. Monteith (1977) developed a model of growth where biomass accumulation is related to solar radiation intercepted by the crop. This model has been largely used for different crops. The conversion factor between radiation absorbed or intercepted by the crop and the biomass production is called “radiation use efficiency” or “dry matter radiation quotient”. Radiation use efficiency (RUE) is usually calculated as the regression coefficient of the linear relationship between crop biomass measured repeatedly during growth and cumulated intercepted or absorbed solar radiation. Demetriades-Shah et al. …

The Effect Of Grassland Management On Bovine Nitrogen Efficiency, N. J. Hoekstra, R. P. O. Schulte, E. A. Lantinga, P. C. Struik

IGC Proceedings (1977-2023)

Nitrogen (N) losses through grazing bovines are at the heart of the current debate on environment and agriculture. N utilisation of grazing bovines is predominantly determined by the form and amount of energy and protein in their diet, which in Ireland consists mainly of grazed grass. The two main problems of grazed grass with respect to animal N utilisation are 1) the imbalance between total N content and energy content, and 2) the lack of synchronisation between the release of N and carbohydrates in the rumen. It was hypothesised that both the balance and synchronisation of N and energy in …

Potential Yield Of Cocksfoot (Dactylis Glomerata) Monocultures In Response To Irrigation And Nitrogen, A. Mills, D. J. Moot, R. L. Lucas, P. D. Jamieson, B. A. Mckenzie

IGC Proceedings (1977-2023)

Cocksfoot is a widely sown grass in temperate pastures. However, while potential yield of cocksfoot can exceed 28 t DM/ha per year, it is often restricted by water, temperature and nitrogen (N). Of these, Peri et al. (2002) showed that N was severely limiting in all seasons. The aim of this study was to confirm the potential yield of cocksfoot and quantify the extent of yield reductions due to environmental constraints.

Blood Meal As A Source Of Histidine For Cattle Fed Grass Silage And Barley, R. Berthiaume, C. Lafrenière

IGC Proceedings (1977-2023)

Previous research has shown that cattle fed grass silage are responsive to protected amino acids (Veira et al., 1991). Methionine and lysine were suggested as the most limiting amino acids for grass silage diets. Recently, Korhonen et al. (2000) have shown that histidine is the first limiting amino acids for dairy cows fed grass silage and barley-based concentrates. However, histidine is not available in a rumen protected form and needs to be provided through dietary ingredients. Blood meal is rich in histidine. This trial was designed to determine the effect of increasing histidine supply through blood meal on …

Assessment Of Variable Rate Nitrogen Application On Rice Cultivars Using Remote Sensing, Rush Matthew Evans

Student Theses and Dissertations

Application of the right time and amount of fertilizer N is challenging in rice fertilization because crop N supply is highly variable in the field. Research plots were established at four research plot fields and one commercial field in Arkansas. Independent variables included six nitrogen (N) application rates (0, 67, 101, 134.5, 168, and 202 kg N ha-1), multiple rice cultivars, and five locations. The response variable was 24 vegetative indices values using high spatio-temporal multispectral and thermal imagery obtained from an Unmanned Aerial Vehicle (UAV). The 134 and 168 kg N ha-1 rates were identified as the control group …

Grassland Productivity And Water Quality: A 21st Century Issue, David M. Nash, P. M. Haygarth

IGC Proceedings (1977-2023)

1. Irrigation and other changes to the hydrological cycle can increase soil and water salinity.
2. Primary salinisation is a natural process that affects much of Europe, Asia, Africa, the Americas and Australia. Secondary salinisation is caused by human activities such as irrigation and land clearing that mobilise salt stored in the soil.
3. The critical water contaminants exported from grasslands are nitrogen, phosphorus, potential pathogens and sediment.
4. The mechanisms responsible for diffuse pollution from grasslands and mitigation strategies are most effectively investigated using a ‘source-mobilisation-transport’ framework.
5. There is a lack of coherent interaction across discipline boundaries that links pollutant sources to impact. …

Respons Komponen Hasil Dan Hasil Varietas Padi Berprotein Tinggi Terhadap Pemberian Dosis Pupuk Nitrogen, Agus Riyanto, Dyah Susanti, Totok Agung Dwi Haryanto

Jurnal Kultivasi

Inpago Unsoed Protani dan Inpari Unsoed P20Tangguh adalah padi (Oryza sativa L.) daya hasil tinggi yang memiliki kandungan protein beras tinggi yang pertumbuhannya dipengaruhi oleh pemupukan nitrogen. Tujuan penelitian ini adalah mengetahui respons komponen hasil dan hasil padi protein tinggi terhadap pupuk nitrogen dan memperoleh dosis optimal pupuk nitrogen untuk varietas Inpago Unsoed Protani dan Inpari Unsoed P20Tangguh. Percobaan dirancang dengan RAK pola faktorial dwi faktor yang diulang tiga kali. Faktor pertama adalah dosis pupuk N yaitu: 0 kg N ha-1, 46 kg N ha-1, 92 kg N ha-1, dan 138 kg N ha-1. Faktor kedua adalah genotipe padi yaitu …

Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby

Theses and Dissertations

12 N treatments in 2020 and 11 in 2021 were replicated four times over four locations in a randomized complete block design. The first research tested the efficacy of CYG for Mississippi corn (Zea mays L.) production. The optimum N rates were calculated by fitting four models. Differences between the CYG rate and AONR were compared. AONR varied from 134 to 301 kg N ha–1 at different management levels. When we compared the AONR to the CYG rate, the CYG rate over-recommended N in 12 of the 14 possible comparisons. The second study compared different VIs, methods, and sensors at …

An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew

Theses and Dissertations

Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …

Nitrification Inhibitor, Nitrogen Source, And Herbicide Effects On Soil Nitrogen Transformations And Corn Yield, William Neels

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

Nitrogen fertilizer management continue to be challenging due to potential nitrogen losses under variable weather conditions. The objective of this was to evaluate the performance of nitrification inhibitors, nitrogen sources and herbicides on in-season nitrogen availability and agronomy indicators. A two site-year field experiment was conducted in silty clay loam soil in corn phase of the corn-soybean rotation at Central Nebraska. The treatments included three herbicide (no pre-emergence, Acuron, Resicore) and five nitrogen treatments: 1) control, 2) anhydrous ammonia, 3) anhydrous ammonia without nitrification inhibitor, 4) urea with nitrification inhibitors, and 5) urea without nitrification inhibitors. Results indicated that nitrogen …

Diagnosing Excess Nitrogen In Rice Using Post-Season Tissue Samples, Kyle Hoegenauer

Graduate Theses and Dissertations

Proper nitrogen (N) management in rice production can be difficult to achieve without the aid of tools such as soil and tissue tests. There are no tests currently available to rice producers that determine whether N has been managed properly throughout the season or that detect instances of over fertilization. Rice stalk samples were collected from N response trials within 3 days of harvest from the primary Arkansas rice growing region in 2016-2018. Stalk samples were analyzed for N concentration through a KCl extraction and spectrofluorometric quantification. Samples analyzed with leaf material intact contained statistically different N concentrations than samples …

Mechanical Aeration And Liquid Dairy Manure: Application Impacts On Grassland Runoff Water Quality And Yield, T. J. Basden, S. B. Shah, J. L. Miller

IGC Proceedings (1977-2023)

Wet weather on heavy soils reduces oxygen availability in the root zone and reduces forage yields. Mechanical aeration can improve forage yield in these soil conditions. Research has shown that under certain conditions, mechanical aeration can increase yield by improving drainage and aeration (Davies et al., 1989); aeration can also increase depression, storage and infiltration thus reducing surface runoff and improving nutrient distribution in the root zone. Aeration on sloping, fertilised grassland can provide environmental (Douglas et al., 1995) and agronomic benefits. The objectives of this study were to evaluate the runoff water quality and agronomic impacts of …

Assessment Of Nitrogen Nutrition Status Of Grasses Under Water Deficit And Recovery, V. G. Dugo, Jean-Louis Durand, F. Gastal

IGC Proceedings (1977-2023)

Grasslands are rarely irrigated. They are therefore systematically submitted to more or less severe water deficits: as well as mineral deficiencies, water scarcity often also results in a reduction of nitrogen (N) status. Although identified some time ago, qualitatively, the interaction with N still remains difficult to take into account in quantitative analyses of crop physiology under water deficits. This paper illustrates how the nitrogen (N) status of the crop changes under water deficits. A N nutrition index (INN) was defined as the ratio of the actual N concentration of forage with the theoretical N concentration under optimal conditions, the …

Nitrogen Mineralisation In Situ And In Controlled Environment, F. Pálmason

IGC Proceedings (1977-2023)

Net mineralisation may be underestimated by in situ soil core methods for at least two reasons: (1) absence of plant N uptake in the soil cores, causing higher immobilisation than in intact soil. Schimel & Bennet (2004) thus concluded that plants compete effectively with microbes, as strongly indicated by cases, where net mineralisation was lower than plant uptake. (2) Gaseous losses of N₂O in closed cylinders can lead to underestimation especially during long incubation periods, Abril et al. (2001) and Vor & Brumme (2002).

The Role Of Grass Tussocks In Maintaining Soil Condition In North East Australia, B. K. Northup, J. R. Brown

IGC Proceedings (1977-2023)

Soils of the grazing lands of north eastern Australia are inherently nutrient-poor. Heterogeneously distributed plants are important to the conservation of the limited amounts of nutrients, through storage in plant tissues or in soil sinks close to plants (Ludwig et al., 1997). Loss of perennial vegetation through disturbance reduces conservation of these resources, to the detriment of feedback mechanisms, and ultimately causes loss of soil condition. Large areas of north east Australia have been degraded, or threatened by degradation, through combinations of variability in precipitation and heavy grazing (Gardener et al., 1990). This study examined the inter-related responses …

Field Experiments To Help Optimise Nitrogen Fixation By Legumes On Organic Farms, A. Joynes, D. J. Hatch, A. Stone, S. Cuttle, G. Goodlass

IGC Proceedings (1977-2023)

During an organic rotation, the aim is to increase the nitrogen (N) content of the soil (and hence build up soil fertility) by recycling crop residues, applying manures/composts and from N fixed by legumes. IGER, with ADAS, Duchy College Cornwall and Abacus Organic Associates are developing improved guidance for organic farmers in the use of fertility-building crops. The main questions are: how to maximise N fixation and how to make the most efficient use of the fixed N? Available soil mineral N, which is generally thought to reduce N fixation, will be increased by manure applications, cutting/mulching and grazing. We …

The Effect Of Forage Legumes On Mineral Nitrogen Content In Soil, M. Isolahti, A. Huuskonen, M. Tuori, Oiva Nissinen, R. Nevalainen

IGC Proceedings (1977-2023)

The cultivation of forage legumes is often suggested as a possibility to improve nitrogen (N) utilisation in farming. However, previous studies have indicated examples in which the cultivation of legumes such as white clover has led to accumulation of large amounts of N in soil (Adams & Pattison, 1985). In this study the potential risks of N leaching were estimated by determining amount of mineral N in the soil.

Cycling Of N And P In Grass-Alone (Brachiaria) And Mixed Grass/Legume (Brachiaria/ Desmodium Ovalifolium) Grazed Pastures In The Atlantic Forest Region Of Brazil, R. M. Boddey, R. Tarré, R. Macedo, C. De P. Rezende, J. M. Pereira, B. J. R. Alves, S. Urquiaga

IGC Proceedings (1977-2023)

There are estimated to be > 80 M ha of Brachiaria pastures in the tropical regions of Brazil. When continuously grazed with only modest fertiliser inputs (and no N) these pastures can maintain reasonable cattle weight gains (> 200 kg LWG/ha per year). However, without fertiliser and when overgrazed, LWGs fall rapidly to low levels. Recent studies have shown that N and P deficiency are the most important factors limiting productivity. The objective of this study was to study fluxes of N and P in the pasture system in order to understand resilience to poor management and minimum nutrient requirements to …

Uji Kemampuan Bakteri Diazotrof Asal Perakaran Bawang Merah Dalam Mendukung Pertumbuhan Dan Hasil Tanaman Bawang Merah, Ananda Rahmalia Yuniarti, Eny Rokhminarsih, Purwanto

Jurnal Kultivasi

Budidaya tanaman bawang merah saat ini dihadapkan pada masalah stagnasi produksi akibat aplikasi pupuk kimia secara berlebihan sehngga efisiensi pemupukan rendah. Teknologi ramah lingkungan dan efisien pupuk dengan aplikasi bioteknologi melalui aplikasi bakteri berguna seperti bakteri penambat nitrogen. Penelitian bertujuan untuk (1) mengetahui respons pertumbuhan dan hasil tanaman bawang merah terhadap bakteri diazotrof, (2) menetapkan isolat bakteri diazotrof yang paling baik untuk pertumbuhan dan hasil tanaman bawang merah. Percobaan dilaksanakan pada bulan Januari 2021 sampai April 2021. Percobaan dilaksanakan di Rumah Kassa serta Laboratorium Agronomi dan Hortikultura Fakultas Pertanian, Universitas Jenderal Soedirman. Rancangan percobaan yang digunakan yaitu Rancangan Acak Kelompok …

Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan R. Mcpherson

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

Arbuscular mycorrhizal fungi (AMF) remain a vital obligate symbiont of nearly all plants. It is well established that the symbiosis between AMF and host plant improves plant nutrient acquisition, alleviates abiotic and biotic environmental stressors, defends against plant pathogens, and contributes to overall plant fitness and productivity through modification of the soil habitat. Modifications include increased soil aggregation and stability, carbon sequestration through provision of fungal wall precursors to soil organic matter (SOM) formation, and enhanced nutrient cycling in the mycorrhizosphere. The goal of this dissertation was to assess how AMF respond to nitrogen (N) fertilization regimes in maize cropping …

Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne

Theses and Dissertations

Corn is one of American agriculture's greatest success stories, where we have witnessed incredible increases in yield potential over the last half-century. However, abiotic stress is still the primary limiting factor preventing plants from reaching their true yield potential. In addition, agriculture is not exempt from the deleterious effects of changing weather patterns and the altered climate our world will face as time progresses. Thus, increasing our understanding of how crops interact with their environment both above and below the soil will be crucial to increasing production on a global scale while maximizing profitability at a local level. Five studies …

Evaluating The Effect Of Coated Urea And Urea-Ammonium-Nitrate Solution On Cane Tonnage, Sugar Yield, And Leaf-Soil Nitrogen Content Under Louisiana Sugarcane Production System, Hector J. Mendoza Lagos

LSU Master's Theses

Nitrogen (N) is a crucial nutrient for proper plant growth and development. N deficiency results in poor tillering and thin, short internode stem production for sugarcane production, thus resulting in low cane tonnage. Therefore, proper N fertilizer management is essential for a sustainable sugarcane production system. This research was conducted at the LSU AgCenter Sugar Research Station in St. Gabriel, LA, from 2019 to 2020 at three Sites (Site 1, 2, and 3). The treatments consisted of different N rates (0, 45, 90, and 135 kg N ha^-1) and sources (urea-ammonium-nitrate solution [UAN]-32%, 30-day [Coated Urea 1], 45-day …

Grassland Productivity And Water Quality: A 21St Century Issue, David M. Nash, P. M. Haygarth

IGC Proceedings (1977-2023)

Key points

1. Irrigation and other changes to the hydrological cycle can increase soil and water salinity.

2. Primary salinisation is a natural process that affects much of Europe, Asia, Africa, the Americas and Australia. Secondary salinisation is caused by human activities such as irrigation and land clearing that mobilise salt stored in the soil.

3. The critical water contaminants exported from grasslands are nitrogen, phosphorus, potential pathogens and sediment.

4. The mechanisms responsible for diffuse pollution from grasslands and mitigation strategies are most effectively investigated using a ‘source-mobilisation-transport’ framework.

5. There is a lack of coherent interaction across discipline …

Post-Termination Effects Of Cover Crop Monocultures And Mixtures On Soil Inorganic Nitrogen And Microbial Communities On Two Organic Farms In Illinois, Eleanor E. Lucadamo, Ashley A. Holmes, Samuel E. Wortman, Anthony C. Yannarell

Department of Agronomy and Horticulture: Faculty Publications

Cover crops can continue to affect agricultural systems even after they have been terminated by influencing nitrogen dynamics and by altering soil microbial communities. These post-termination effects can influence soil fertility, weed pressure, and the dynamics of potential plant pathogens in the narrow window of time between cover crop termination and cash crop emergence. We evaluated the post-termination effects of 12 different spring-sown cover crop mixtures and monocultures on soil nitrogen and microbial communities on two different organic farms in Central Illinois (on Lawson silt loam soil) and Northern Illinois (on Virgil silt loam soil). In comparison to control plots …

Post-Termination Effects Of Cover Crop Monocultures And Mixtures On Soil Inorganic Nitrogen And Microbial Communities On Two Organic Farms In Illinois, Eleanor E. Lucadamo, Ashley A. Holmes, Samuel E. Wortman, Anthony C. Yannarell

Department of Agronomy and Horticulture: Faculty Publications

Cover crops can continue to affect agricultural systems even after they have been terminated by influencing nitrogen dynamics and by altering soil microbial communities. These post-termination effects can influence soil fertility, weed pressure, and the dynamics of potential plant pathogens in the narrow window of time between cover crop termination and cash crop emergence. We evaluated the post-termination effects of 12 different spring-sown cover crop mixtures and monocultures on soil nitrogen and microbial communities on two different organic farms in Central Illinois (on Lawson silt loam soil) and Northern Illinois (on Virgil silt loam soil). In comparison to control plots …

Elevated Co2 And Extreme Climatic Events Modify Nitrogen Content And Ruminal Protein Digestion Of Temperate Grassland, V. Niderkorn, C. Picon-Cochard

IGC Proceedings (1977-2023)

This study was aimed at analyzing changes in nitrogen (N) content and in vitro protein rumen digestion of an upland grassland exposed to climate changes in controlled conditions. Monoliths of grassland were inserted in 12 macrocosms in which climatic conditions for the 2050s were simulated (i.e., +2.3°C and 33 mm less precipitation compared to the current climatic conditions). Six of them were subjected to ambient CO₂ (390 ppm) while the other six were subjected to elevated CO₂ (520 ppm). After four months, an extreme climatic event (ECE) consisting of four weeks of reducted precipitation (-50%) followed by two …

Effect Of Native Grassland Intensification Over Cattle Performance, N. Caram, F. Casalás, M. Cadenazzi, R. Zanoniani, P. Boggiano

IGC Proceedings (1977-2023)

The objective was to evaluate the effect of different levels of intensification in native grassland over cattle live weight gain (LWG), stocking rate (SR) and average daily gain (ADG) in Uruguay. The study was carried out in 7.8 ha in Paysandú, between winter 2015 and autumn 2019. Experiment was a randomized complete block design, with 4 replicates. The four treatments applied were native grassland (NG), NG overseeded with Trifolium pratense (6 kg.ha^-1) and Lotus tenuis (6 kg.ha^-1) + 40 kg.ha^-1 of P₂O₅ (NGO), NG fertilized with 60 kg.ha^-1 of N + …

Mapping Nitrogen Fixing Shrubs In Dry Unimproved Tussock Grassland, C. C. Boswell, W. L. Lowther, P. D. Espie

IGC Proceedings (1977-2023)

Global Positioning System (GPS) was used to both map the positions of individual nitrogen-fixing shrub plants and record individual plant height and breadth dimensions, within a small catchment of dry sub-humid unimproved short tussock grassland. The distributions of different species of shrubs varied with different landscape units within the catchment. The information will provide the base data for a first approximation of the role of the shrubs in the nitrogen balance of the ecosystem, which is pivotal to the sustainability of pastoral farming in the tussock grasslands.

Importance Of Haresfoot Clover (Trifolium Arvense) As A Nitrogen Fixer In Semi-Arid Grasslands Of New Zealand, C. C. Boswell, W. L. Lowther, P. R. Espie

IGC Proceedings (1977-2023)

The aim of the study was to determine the distribution of annual haresfoot clover (Trifolium arvense) in a depleted indigenous short tussock grassland catchment in the dry subhumid MacKenzie Basin, South Island, New Zealand. Haresfoot clover was present on all landscapes, and widely distributed on lower sunny aspects, suggesting that it is an important component of the nitrogen cycle in these environments even in the absence of fertiliser application. The study was conducted during an atypically moist summer when a bloom of the annual clover occurred. Nitrogen inputs will vary with landscape and spring/summer rainfall and it is …

Vegetation Changes In Southeast Australian Temperate Grasslands, D. L. Garden, T. P. Bolger

IGC Proceedings (1977-2023)

In temperate areas of southeast Australia, the combined effects of tree clearing, grazing, application of fertilizer and the introduction of exotic species have modified the original grasslands. This paper describes these changes and attempts to explain them in terms of ecological principles derived from North American grasslands. Stability of the original grasslands appears to have been due to the lack of disturbance and the slow rates of nitrogen (N) cycling within them. Increased N cycling after disturbance has allowed invasion of species better adapted to higher N status, particularly exotic annual grasses and weeds. The present composition of grasslands, in …