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Full-Text Articles in Agronomy and Crop Sciences

Compatibility Of Stylosanthes Hamata And Stylosanthes Capitata In Mixed Pastures In The Subhumid Zone Of Nigeria, G Tarawali, M Peters Jun 2024

Compatibility Of Stylosanthes Hamata And Stylosanthes Capitata In Mixed Pastures In The Subhumid Zone Of Nigeria, G Tarawali, M Peters

IGC Proceedings (1997-2023)

The forage productivity of sole plots of Stylosanthes capitata and Stylosanthes hamata in comparison with various proportional mixtures of the two legumes and their effect on soil properties and subsequent maize yield were studied in subhumid Nigeria. Dry matter (DM) yields in the mixtures were higher than in the sole stands, with the mixtures of S. hamata and S. capitata reaching 11959 to 14822 kg/ha over a three year period. Total nitrogen and/or organic carbon concentrations in the soil following the three years of legume were higher in the mixtures than in the sole stands, and this resulted in higher …


Long Term Benefits Of Diversified Forage-Oriented Cropping Systems As Compared To Rotations Based Mainly On Cereals Or Maize, E Meister, V Mediavilla, P Weisskopf Jun 2024

Long Term Benefits Of Diversified Forage-Oriented Cropping Systems As Compared To Rotations Based Mainly On Cereals Or Maize, E Meister, V Mediavilla, P Weisskopf

IGC Proceedings (1997-2023)

The aim of this study is to assess the long term effects of a forageoriented, versus a maize- and a cereal-oriented crop rotation on the yield potential and soil fertility, as well as the weed, disease and pest development. We report the results after four cropping cycles using silage maize (Zea mays L.) in 1994 and winter wheat (Triticum aestivum L.) in 1995 as reference crops for all three rotations. Two years of a grass-clover mixture in a five-year rotation showed positive effects with respect to most soil and plant parameters.


Multiple Uses Of Tropical Forage Legumes For Sustainable Farming In The Moist Savannas Of Africa, L Muhr, S A. Tarawali, M Peters, U Merkel, R Schultze-Kraft, D Berner Jun 2024

Multiple Uses Of Tropical Forage Legumes For Sustainable Farming In The Moist Savannas Of Africa, L Muhr, S A. Tarawali, M Peters, U Merkel, R Schultze-Kraft, D Berner

IGC Proceedings (1997-2023)

Ensuring that farming in the moist savannas of Africa is maintained, despite increasing population pressure and agricultural demands, necessitates the sustainable integration of crop and livestock enterprises; a role that forage legumes can fulfill. The potential of eleven herbaceous and two shrubby species of forage legumes in an improved fallow or ley-farming system to provide dry season fodder and beneficial effects to a subsequent cereal crop were investigated. Fodder dry matter yields were highest for Stylosanthes guianensis (9.9 t/ha), Centrosema pubescens, and Aeschynomene histrix. Maize yield following S. guianensis was 138% higher than after natural fallow. Similar increases were …


The Beneficial Effects Of Short-Term Rotation Systems Of Winter Forage Crops With Maize On Dry Farming Land Of Southwestern China, S R. Zhou, U Simon, K Mao Jun 2024

The Beneficial Effects Of Short-Term Rotation Systems Of Winter Forage Crops With Maize On Dry Farming Land Of Southwestern China, S R. Zhou, U Simon, K Mao

IGC Proceedings (1997-2023)

The objective of this study was to sift out the suitable and better short-term rotation systems of winter forage mixture with maize on dry farming land for the local farmers in Southwestern China. Four species of legume, Italian ryegrass and maize were used to organize six treatments for this experiment. The result showed that the three rotation systems of Astragalus sinicus (80%) + Lolium multiflorum (20%) ’ Zea mays, Medicago hisida (70%) + Lolium multiflorum (30%) ’ Zea mays and Vicia villosa (75%) + Lolium multiflorum (25%) ’ zea mays obtained good forage values (TDOM 4.06-4.36 t/ ha, CP 1.10-1.58 …


Life Cycle Greenhouse Gas Emissions In Maize No-Till Agroecosystems In Southern Brazil Based On A Long-Term Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimelio Bayer Jan 2024

Life Cycle Greenhouse Gas Emissions In Maize No-Till Agroecosystems In Southern Brazil Based On A Long-Term Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimelio Bayer

Department of Biological Systems Engineering: Papers and Publications

Brazilian agriculture is constantly questioned concerning its environmental impacts, particularly greenhouse gas (GHG) emissions. This research study used data from a 34-year field experiment to estimate the life cycle GHG emissions intensity of maize production for grain in farming systems under no-tillage (NT) and conventional tillage (CT) combined with Gramineae (oat) and legume (vetch) cover crops in southern Brazil. We applied the Feedstock Carbon Intensity Calculator for modeling the “field-to-farm gate” emissions with measured annual soil N2O and CH4 emissions data. For net CO2 emissions, increases in soil organic C (SOC) were applied as a proxy, …


Evaluation Of Sweet Grain Sorghum Silage For Dairy Cows As An Alternative To Irrigated Maize Silage, W. G. Do Nascimento, Y. Barrière, X. Charrier, Christian Huyghe, J. C. Emile Aug 2023

Evaluation Of Sweet Grain Sorghum Silage For Dairy Cows As An Alternative To Irrigated Maize Silage, W. G. Do Nascimento, Y. Barrière, X. Charrier, Christian Huyghe, J. C. Emile

IGC Proceedings (1997-2023)

Under European dairy cattle rearing conditions, whole plant maize silage is the main part of the dairy cow's diet especially during the winter season. Nevertheless maize production can be limited in some areas because summer rainfall is insufficient and so irrigation is necessary. Grain sorghum hybrids, and especially sweet sorghum types, are potentially of great interest to avoid this water consumption (Lemaire et al., 1996, Legarto, 2000). For this reason we evaluated in 2003 the benefits and limits of a sweet grain sorghum silage for dairy milk production, compared to an irrigated maize silage. We paid particularl attention to …


Effects Of Cattle Slurry, Their Solid And Liquid Fractions And Mineral N Fertilizers On Italian Ryegrass And Maize Forage Yield, H. Trindade, J. Coutinho, N. Moreira Aug 2023

Effects Of Cattle Slurry, Their Solid And Liquid Fractions And Mineral N Fertilizers On Italian Ryegrass And Maize Forage Yield, H. Trindade, J. Coutinho, N. Moreira

IGC Proceedings (1997-2023)

Solid-liquid slurry separation techniques expand possibilities to improve slurry use efficiency and to reduce its negative environmental impact. These possibilities arise from the different behaviour of the two fractions concerning the release of nutrients, namely nitrogen (N), due to different C:N ratios (≈30 for the solid fraction and ≈7 for the liquid fraction).

The aim of this work was to evaluate the effect of cattle-slurry and their solid and liquid fractions applied at sowing time of Italian ryegrass (Lolium multiflorum cv. Andrea) and forage maize on crop dry matter (DM) yield. In the NW region of Portugal these two …


Effects Of Nitrogen Fertiliser On Nitrate Leaching And Production Of Autumn-Sown Italian Ryegrass In A Double-Cropping System On A New Zealand Dairy Farm, Errol R. Thom, A. A. Judge, R. N. Jensen, M. S. Sprosen, Sterwart F. Ledgard, W. D. Catto Aug 2023

Effects Of Nitrogen Fertiliser On Nitrate Leaching And Production Of Autumn-Sown Italian Ryegrass In A Double-Cropping System On A New Zealand Dairy Farm, Errol R. Thom, A. A. Judge, R. N. Jensen, M. S. Sprosen, Sterwart F. Ledgard, W. D. Catto

IGC Proceedings (1997-2023)

On intensive dairy farms in New Zealand, winter Italian ryegrass crops are combined with summer maize silage crops in double-cropping systems. Limited data (Davies & Neilson, 1975) showed variable ryegrass yield responses to nitrogen (N) fertiliser when grown after maize. Nitrogen leaching losses were not measured in this experiment but Ledgard et al. (1988) showed that late autumn/early winter N applications are vulnerable to leaching. Different rates of N fertiliser were applied to Italian ryegrass grown after maize to assess yield responses and levels of nitrate leaching.


Increase In Forage Maize Production By Bacterial Fertilisers, D. Egamberdiyeva, G. Hoflich Aug 2023

Increase In Forage Maize Production By Bacterial Fertilisers, D. Egamberdiyeva, G. Hoflich

IGC Proceedings (1997-2023)

Farmers in many countries value green material generated from maize as a high quality forage. Its inclusion in dairy cow diets can improve forage intake, increase animal performance and has the potential to reduce production costs (Phipps, 1994). Restrictions on the use of chemical fertilisers and a renewed interest in organic sustainable farming systems in general, has restored attention to crop rotations The increase of maize production using bacterial fertilisers also gives alternative ways to reduce chemical fertilisers in forage production. Increased uptake of nutrients such as N, P, and K and crop yield was reported with rhizobacteria (Lazarovits & …


The Effects Of Offering Grass Or Maize Silages To In-Lamb Ewes On Body Weight And Condition Changes, Colostrum Yield And Quality, T. F. Crosby, P. J. Quinn, J. J. Callan, P. Reilly, B. Flynn, D. Cunningham, T. Massey Jun 2023

The Effects Of Offering Grass Or Maize Silages To In-Lamb Ewes On Body Weight And Condition Changes, Colostrum Yield And Quality, T. F. Crosby, P. J. Quinn, J. J. Callan, P. Reilly, B. Flynn, D. Cunningham, T. Massey

IGC Proceedings (1997-2023)

Hay and more recently grass silage (GS) have been the traditional feeds for sheep in Ireland over the winter period. Alternatives such as maize silage (MS) are becoming increasingly important as winter forage sources especially for cattle. This study sought to evaluate grass silage and maize silage when offered to pregnant ewes.


Factors Affecting Bag Silo Densities And Losses, R. E. Muck, B. J. Holmes Jun 2023

Factors Affecting Bag Silo Densities And Losses, R. E. Muck, B. J. Holmes

IGC Proceedings (1997-2023)

Bag silos (polyethylene tubes, 30 to 90 m length, 2.4 to 3.7 m diameter, 0.22 mm thick) are used on approximately one-third of the dairy farms in the U.S.A. for making silage, and the level of adoption is increasing rapidly. Unfortunately, almost no research data have been published on these types of silos. Our objective was to measure densities and losses in bag silos at three farms, looking for causes of variation in both.


Effect Of A New Microbial Strain As An Inoculant On The Quality Of Maize Silage, J. G. Kim, J. S. Ham, E. S. Chung, S. Seo, J. K. Lee Jun 2023

Effect Of A New Microbial Strain As An Inoculant On The Quality Of Maize Silage, J. G. Kim, J. S. Ham, E. S. Chung, S. Seo, J. K. Lee

IGC Proceedings (1997-2023)

Lactic acid bacteria play a key role in making silage from forage, and lactic acid bacteria selected from good silage could be expected to be suitable inocula for making good silage. Thus, the purpose of this study was to examine the such novel lactic acid bacteria for making high quality maize silage.


Options For Improved Biomass Production In Feeding Systems For Dairying In High Rainfall Environments In New Zealand, John M. De Ruiter, D. R. Wilson, S. Maley, S. M. Henton Jun 2023

Options For Improved Biomass Production In Feeding Systems For Dairying In High Rainfall Environments In New Zealand, John M. De Ruiter, D. R. Wilson, S. Maley, S. M. Henton

IGC Proceedings (1997-2023)

New Zealand dairy production has expanded into marginal climates and soil types on the premise of excellent profitability and efficient utilisation of forage. Annual pasture production in the cool West Coast of the South Island (rainfall 2042-2933 mm) is15,000 kg. Increased farm production and feeding of high quality biomass, from imported feed or supplementary feed crops grown on- farm, are needed to improve milk solid output. Small plot trials with spring and early summer-sown brassicas, cereals and maize were the focus for development of systems to maximise and manage the seasonal feed supply. The effect of sowing time, fertiliser timing …


Ensiling Characteristics And Nutritive Value Of Browse/Maize Forage Mixtures, F. B. Bareeba, H. Kato, Elly N. Sabiiti Jun 2023

Ensiling Characteristics And Nutritive Value Of Browse/Maize Forage Mixtures, F. B. Bareeba, H. Kato, Elly N. Sabiiti

IGC Proceedings (1997-2023)

The practice of growing fodder tree and shrubs is being advocated for and adopted in smallholder dairy production systems. In Uganda, Calliandra calothyrsus, Gliricidia sepium, and Leucaena leucocephala have been identified and recommended as the most suitable species (Sabiiti, 2001). However tree foliage contains toxic compounds (Lowry, 1990), which may be alleviated by ensiling. The objective of the experiment was to study the ensiling characteristics of browse/ maize forage mixtures and their nutritive value when fed to lactating dairy cows.


Irish Dairy Farming: Effects Of Introducing A Maize Component On Grassland Management Over The Next 50 Years, A. J. Brereton, N. M. Holden Feb 2023

Irish Dairy Farming: Effects Of Introducing A Maize Component On Grassland Management Over The Next 50 Years, A. J. Brereton, N. M. Holden

IGC Proceedings (1997-2023)

Typical management of Irish dairy units is based on a low-cost spring-calving strategy with 90% of annual feed derived from grass grown on the farm. Almost 70% of feed is from grazed grass managed by rotational grazing, the remainder is conserved forage and concentrates. The objectives of the work were to examine how the management system has to be modified when part of the dairy unit land is allocated to maize silage instead of grass silage production, and to examine how climate change over the next 50 years will impact on grass and maize management within the production system.


The Feeding Value Of Conserved Whole-Crop Wheat And Forage Maize Relative To Grass Silage And Ad-Libitum Concentrates For Beef Cattle, K. Walsh, P. O'Kiely, F. O'Mara Feb 2023

The Feeding Value Of Conserved Whole-Crop Wheat And Forage Maize Relative To Grass Silage And Ad-Libitum Concentrates For Beef Cattle, K. Walsh, P. O'Kiely, F. O'Mara

IGC Proceedings (1997-2023)

Grass is the predominant forage ensiled in Ireland. However, the relatively modest yields achieved in a single harvest allied to variability in digestibility and ensilability (and thus in intake and animal performance response) and the likelihood of effluent production create disadvantages for grass silage compared to the potential of some alternative forage crops. Thus, alternative forages are worthy of consideration on many farms. The objectives of this study were to quantify the relative intake, digestibility and performance of beef cattle offered grass silage, forage maize silage and whole-crop wheat (fermented or urea-treated), rank these relative to cattle offered an ad …


Yield And Composition Of Forage Maize: Interaction Of Harvest Date, Cultivar And Plastic Mulch, E. M. Little, P. O'Kiely, J. C. Crowley, G. P. Keane Feb 2023

Yield And Composition Of Forage Maize: Interaction Of Harvest Date, Cultivar And Plastic Mulch, E. M. Little, P. O'Kiely, J. C. Crowley, G. P. Keane

IGC Proceedings (1997-2023)

Forage maize is established as a crop with the potential to consistently supply high yields of quality forage on some Irish farms. Despite its success, considerable variability in crop yield, quality and maturity at harvest can exist from year to year. These reflect differing prevailing weather conditions, particularly temperature during May to September. The use of plastic mulch has increased the likelihood of achieving higher yields of high quality crops and has permitted maize production to extend into areas once considered unsuitable for the crop. In this experiment two cultivars of differing maturity were grown with or without plastic mulch …


Fermentation Characteristics Of Maize/Sesbania Bi-Crop Silage, M. Kondo, J. Yanagisawa, K. Kita, H. Yokota Feb 2023

Fermentation Characteristics Of Maize/Sesbania Bi-Crop Silage, M. Kondo, J. Yanagisawa, K. Kita, H. Yokota

IGC Proceedings (1997-2023)

Maize is one of the main forages for dairy production and is a suitable material for silage making because of high fermentable carbohydrates, high counts of lactic acid bacteria (LAB) and low buffering capacity (BC) (Nishino et al. 2003; McDonald et al. 1991). Whole crop maize silage is high in energy but low in crude protein (CP). On the other hand, legumes are high in CP but difficult to conserve because of their low water soluble carbohydrates (WSC) and high BC. It might be possible that maize/legume bi-crop silage compensate for their negative points. Sesbania is a legume originated …


An Evaluation Of The Inclusion Of Alternative Forages With Grass Silage-Based Diets On Carcass Composition And Meat Quality Of Beef Cattle Offered Two Contrasting Grass Silages, T. W. J. Keady, F. O. Lively, D. J. Kilpatrick, B. W. Moss Feb 2023

An Evaluation Of The Inclusion Of Alternative Forages With Grass Silage-Based Diets On Carcass Composition And Meat Quality Of Beef Cattle Offered Two Contrasting Grass Silages, T. W. J. Keady, F. O. Lively, D. J. Kilpatrick, B. W. Moss

IGC Proceedings (1997-2023)

Recent studies have shown that the inclusion of some alternative forages with grass silage-based diets can increase animal performance of beef cattle. The aim of the present study was to evaluate the effects of including either maize or whole crop wheat (WCW) silages with grass silage-based diets on meat quality of beef cattle offered two levels of concentrate.


Comparison Of Different Maize Hybrids Cultivated And Fermented With Or Without Sorghum, Sz. Orosz, Z. Bellus, Zs. Kelemen, E. Zerényi, J. Helembai Feb 2023

Comparison Of Different Maize Hybrids Cultivated And Fermented With Or Without Sorghum, Sz. Orosz, Z. Bellus, Zs. Kelemen, E. Zerényi, J. Helembai

IGC Proceedings (1997-2023)

In Hungary our key forage crop is silage maize, however, the joint growing of maize and sorghum is increasingly important in arid regions. The reason is, that sorghum varieties tolerate well the various ecological stresses (drought). The joint growing of maize and sorghum varieties has several advantages and disadvantageous in respect of yields, safety of production, fermentability of the crop and nutrient content of the silage. The basis of realising the complementary qualities of the two crops and of the successful joint growing and preservation is the suitable pairing of hybrid varieties.


Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio Dec 2019

Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio

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

A nitrogen (N) balance, calculated as the difference between N inputs and grain-N removal, provides an estimate of the potential N losses. We used N balance with other N-related metrics (partial factor productivity for N inputs, and yield-scaled N balance), to benchmark maize yields in relation with N input use in the US Corn Belt. We first used experimental data on grain-N concentration (GNC) to assess variation in this parameter due to biophysical and management factors. Subsequently, we used N balance and N-related metrics to benchmark yields in relation with N inputs in irrigated and rainfed fields in Nebraska using …


Extreme‐Phenotype Genome‐Wide Association Study (Xp‐Gwas): A Method For Identifying Trait‐Associated Variants By Sequencing Pools Of Individuals Selected From A Diversity Panel, Jinliang Yang, Haiying Jiang, Cheng-Ting Yeh, Jianming Yu, Jeffrey A. Jeddeloh, Dan Nettleton, Patrick S. Schnable Jun 2019

Extreme‐Phenotype Genome‐Wide Association Study (Xp‐Gwas): A Method For Identifying Trait‐Associated Variants By Sequencing Pools Of Individuals Selected From A Diversity Panel, Jinliang Yang, Haiying Jiang, Cheng-Ting Yeh, Jianming Yu, Jeffrey A. Jeddeloh, Dan Nettleton, Patrick S. Schnable

Dan Nettleton

Although approaches for performing genome‐wide association studies (GWAS) are well developed, conventional GWAS requires high‐density genotyping of large numbers of individuals from a diversity panel. Here we report a method for performing GWAS that does not require genotyping of large numbers of individuals. Instead XP‐GWAS (extreme‐phenotype GWAS) relies on genotyping pools of individuals from a diversity panel that have extreme phenotypes. This analysis measures allele frequencies in the extreme pools, enabling discovery of associations between genetic variants and traits of interest. This method was evaluated in maize (Zea mays) using the well‐characterized kernel row number trait, which was …


Extensive Tissue-Specific Transcriptomic Plasticity In Maize Primary Roots Upon Water Deficit, Nina Opitz, Caroline Marcon, Anja Paschold, Waqas Ahmed Malik, Andrew Lithio, Ronny Brandt, Hans-Peter Piepho, Dan Nettleton, Frank Hochholdinger Jun 2019

Extensive Tissue-Specific Transcriptomic Plasticity In Maize Primary Roots Upon Water Deficit, Nina Opitz, Caroline Marcon, Anja Paschold, Waqas Ahmed Malik, Andrew Lithio, Ronny Brandt, Hans-Peter Piepho, Dan Nettleton, Frank Hochholdinger

Dan Nettleton

Water deficit is the most important environmental constraint severely limiting global crop growth and productivity. This study investigated early transcriptome changes in maize (Zea mays L.) primary root tissues in response to moderate water deficit conditions by RNA-Sequencing. Differential gene expression analyses revealed a high degree of plasticity of the water deficit response. The activity status of genes (active/inactive) was determined by a Bayesian hierarchical model. In total, 70% of expressed genes were constitutively active in all tissues. In contrast, <3% (50 genes) of water deficit-responsive genes (1915) were consistently regulated in all tissues, while >75% (1501 genes) were specifically regulated in a single root tissue. Water deficit-responsive genes were most numerous in the …


Mu Transposon Insertion Sites And Meiotic Recombination Events Co-Localize With Epigenetic Marks For Open Chromatin Across The Maize Genome, Sanzhen Liu, Cheng-Ting Yeh, Tieming Ji, Kai Ying, Haiyan Wu, Ho Man Tang, Yan Fu, Daniel S. Nettleton, Patrick S. Schnable Jun 2019

Mu Transposon Insertion Sites And Meiotic Recombination Events Co-Localize With Epigenetic Marks For Open Chromatin Across The Maize Genome, Sanzhen Liu, Cheng-Ting Yeh, Tieming Ji, Kai Ying, Haiyan Wu, Ho Man Tang, Yan Fu, Daniel S. Nettleton, Patrick S. Schnable

Dan Nettleton

The Mu transposon system of maize is highly active, with each of the ∼50–100 copies transposing on average once each generation. The approximately one dozen distinct Mutransposons contain highly similar ∼215 bp terminal inverted repeats (TIRs) and generate 9-bp target site duplications (TSDs) upon insertion. Using a novel genome walking strategy that uses these conserved TIRs as primer binding sites, Mu insertion sites were amplified from Mu stocks and sequenced via 454 technology. 94% of ∼965,000 reads carried Mu TIRs, demonstrating the specificity of this strategy. Among these TIRs, 21 novel Mu TIRs were discovered, revealing additional complexity of …


Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed Aug 2018

Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed

Department of Biological Systems Engineering: Papers and Publications

One perceived cost of integrating winter cover cropping in maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation systems is the potential negative impact on soil water storage available for primary crop production. The objective of this 3-year study was to evaluate the effects of winter cover crops on soil water storage and cover crop biomass production following no-till maize and soybean rotations. Locations were near Brule (west-central), Clay Center (south-central), Concord (northeast), and Mead (east-central), Nebraska, United States. Treatments included crop residue only (no cover crop) and a multi-species cover crop mix, both broadcast-seeded before …


Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani Apr 2017

Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani

Department of Geography: Dissertations, Theses, and Student Research

The gross primary production (GPP) metric is useful in determining trends in the terrestrial carbon cycle. Models that determine GPP utilizing the light use efficiency (LUE) approach in conjunction with biophysical parameters that account for local weather conditions and crop specific factors are beneficial in that they combine the accuracy of the biophysical model with the versatility of the LUE model. One such model developed using in situ data was adapted to operate with remote sensing derived leaf area index (LAI) data and gridded weather datasets. The model, known as the Light Use Efficiency GPP Model (EGM), uses a four …


Coupling Of Carbon Dioxide And Water Vapor Exchanges Of Irrigated And Rainfed Maize–Soybean Cropping Systems And Water Productivity, Andrew E. Suyker, Shashi B. Verma Jan 2010

Coupling Of Carbon Dioxide And Water Vapor Exchanges Of Irrigated And Rainfed Maize–Soybean Cropping Systems And Water Productivity, Andrew E. Suyker, Shashi B. Verma

School of Natural Resources: Faculty Publications

Continuous measurements of CO2 and water vapor exchanges made in three cropping systems (irrigated continuous maize, irrigated maize–soybean rotation, and rainfed maize–soybean rotation) in eastern Nebraska, USA during 6 years are discussed. Close coupling between seasonal distributions of gross primary production (GPP) and evapotranspiration (ET) were observed in each growing season. Mean growing season totals of GPP in irrigated maize and soybean were 1738 ± 114 and 996 ± 69 g C m−2, respectively (±standard deviation). Corresponding mean values of growing season ET totals were 545 ± 27 and 454 ± 23 mm, respectively. Irrigation affected GPP …