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Arkansas Soybean Performance Tests 2022, J. F. Carlin, R. B. Mulloy, R. D. Bond
Arkansas Soybean Performance Tests 2022, J. F. Carlin, R. B. Mulloy, R. D. Bond
Arkansas Agricultural Experiment Station Research Series
Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture’s Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/ or marketing seed within the state, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.
Climate And Agronomy, Not Genetics, Underpin Recent Maize Yield Gains In Favorable Environments, Gonzalo Rizzo, Juan Pablo Monzon, Fatima Amor Tenorio, Réka Howard, Kenneth G. Cassman, Patricio Grassini
Climate And Agronomy, Not Genetics, Underpin Recent Maize Yield Gains In Favorable Environments, Gonzalo Rizzo, Juan Pablo Monzon, Fatima Amor Tenorio, Réka Howard, Kenneth G. Cassman, Patricio Grassini
Department of Agronomy and Horticulture: Faculty Publications
Quantitative understanding of factors driving yield increases of major food crops is essential for effective prioritization of research and development. Yet previous estimates had limitations in distinguishing among contributing factors such as changing climate and new agronomic and genetic technologies. Here, we distinguished the separate contribution of these factors to yield advance using an extensive database collected from the largest irrigated maize-production domain in the world located in Nebraska (United States) during the 2005-to-2018 period. We found that 48% of the yield gain was associated with a decadal climate trend, 39% with agronomic improvements, and, by difference, only 13% with …
A Systematic Review Of Durum Wheat: Enhancing Production Systems By Exploring Genotype, Environment, And Management (G × E × M) Synergies, Brian L. Beres, Elham Rahmani, John M. Clarke, Patricio Grassini, Curtis J. Pozniak, Cameron Guy Robinson Geddes, Kenton D. Porker, William E. May, Joel Ransom
A Systematic Review Of Durum Wheat: Enhancing Production Systems By Exploring Genotype, Environment, And Management (G × E × M) Synergies, Brian L. Beres, Elham Rahmani, John M. Clarke, Patricio Grassini, Curtis J. Pozniak, Cameron Guy Robinson Geddes, Kenton D. Porker, William E. May, Joel Ransom
Department of Agronomy and Horticulture: Faculty Publications
According to the UN-FAO, agricultural production must increase by 50% by 2050 to meet global demand for food. This goal can be accomplished, in part, by the development of improved cultivars coupled with modern best management practices. Overall, wheat production on farms will have to increase significantly to meet future demand, and in the face of a changing climate that poses risk to even current rates of production. Durum wheat [Triticum turgidum L. ssp. durum (Desf.)] is used largely for pasta, couscous and bulgur production. Durum producers face a range of factors spanning abiotic (frost damage, drought, and sprouting) and …
Winter Grazing Management, Stephen K. Barnhart, James R. Russell, Douglas L. Karlen, Michael J. Tidman
Winter Grazing Management, Stephen K. Barnhart, James R. Russell, Douglas L. Karlen, Michael J. Tidman
Douglas L Karlen
Why winter grazing? Beef cow herd and sheep flock records show that winter feeding costs are livestock producers' single largest production expense. Managing through winter weather while keeping feeding costs low is an essential part of maintaining a profitable operation. Iowa's climate generally allows forage growth only during a 7-to-8 month period. Extending the grazing of this forage--even an extra 3 or 4 weeks in late autumn and winter--is an economical way to maintain or increase livestock profitability. Some producers extend the grazing season by using stockpiled forage, whereas others use crop residue, and many combine the use of stockpiled …
Why Manage Phosphorus?, John E. Sawyer, Antonio P. Mallarino
Why Manage Phosphorus?, John E. Sawyer, Antonio P. Mallarino
John E. Sawyer
There are 17 nutrients that are essential for plant growth and production. An insufficient supply of one or more can have an adverse effect on plant growth, maturity, and yield. Phosphorus (P)--one of three key macronutrients (nitrogen and potassium are the other two)--is present in every living plant and animal cell, and is vital in plants for harvesting the sun's energy for growth and reproduction. This requirement is the same whether the plant is growing on soil or in water (such as algae); hence, the concern regarding P levels in surface water and the accelerated aquatic plant growth associated with …
Yellow Corn, Wet Soils, And Nitrogen Loss (Part 3), John E. Sawyer
Yellow Corn, Wet Soils, And Nitrogen Loss (Part 3), John E. Sawyer
John E. Sawyer
Earlier I provided observations in two articles (June 19 and June 26, 2008) on corn growth and response to nitrogen (N) applied in an anhydrous ammonia study being conducted at the ISU research farm between Ames and Boone. Following are some final observations (July 7, 2008).
Wait Until Soil Temps Drop Before Applying Anhydrous Ammonia, John E. Sawyer, Barbara Stewart, William Ehm
Wait Until Soil Temps Drop Before Applying Anhydrous Ammonia, John E. Sawyer, Barbara Stewart, William Ehm
John E. Sawyer
With the early harvest, Iowa’s conservation leaders are encouraging farmers to wait until soil temperatures lower before applying anhydrous ammonia (NH3) this fall. Anhydrous ammonia applied before daily soil temperatures remain below 50 degrees Fahrenheit and continue trending lower can result in the nitrogen loss that can impact crop development and have negative environmental impacts, such as enhanced leaching into groundwater and streams once converted to nitrate.
Wet Conditions And Change In Soil Profile Nitrate, John E. Sawyer
Wet Conditions And Change In Soil Profile Nitrate, John E. Sawyer
John E. Sawyer
I wrote an ICM News article February 21, 2013, that provided a summary of fall soil profile nitrate sampling results following the 2012 corn harvest. As I cautioned in that and other articles, the amount of nitrate-N that might remain for a 2013 corn crop depends on springtime rainfall. Unfortunately, much of Iowa has received considerable precipitation since soils thawed, especially the eastern two-thirds of Iowa. The two maps of the Midwest region show the total precipitation and deviation from normal since March 7, 2013. Tile lines are flowing again, and nitrate in the profile will move with percolating water. …
Uan And Preemergence Herbicide Applications On Emerged Corn, Michael D. Owen, John E. Sawyer, Robert G. Hartzler
Uan And Preemergence Herbicide Applications On Emerged Corn, Michael D. Owen, John E. Sawyer, Robert G. Hartzler
John E. Sawyer
Planting the Iowa 2007 corn crop is somewhat behind recent years, and in efforts to stay ahead of the game, many fields will be planted before being treated with nitrogen (N) and/or herbicides. Corn in some of these fields will emerge before applications of these materials are made, raising concerns over the safety of postemergence applications of urea-ammonium nitrate (UAN) solution, with or without herbicides.
Soybean Top Dieback Shows Up In Iowa Again, Xiao-Bing Yang, John E. Sawyer
Soybean Top Dieback Shows Up In Iowa Again, Xiao-Bing Yang, John E. Sawyer
John E. Sawyer
Extension field agronomists report the occurrence of soybean top dieback in northeastern Iowa soybean fields this week. Soybean top dieback symptoms have shown up occasionally since it was first reported by Jim Fawcett and Jerry Long in Cedar County a few years ago. Last year it was also found in eastern and central Iowa.
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project is designed to study the N fertilization needs in continuous corn (C-C) and corn rotated with soybeans (C-S) as influenced by location and climate. Multiple rates of fertilizer N are spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow the determination of N requirements for each rotation practice, differences that exist between the two rotations, and responses to applied N across different soils and climatic conditions. It will also allow for the evaluation of tools used to adjust …
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (SC) as influenced by location and climate. Multiple rates of fertilizer N were spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow the determination of N requirements for each rotation practice, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project is designed to study the N fertilization needs in continuous corn (C-C) and corn rotated with soybean (C-S) as influenced by location and climate. Multiple rates of fertilizer N are spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will help determine N requirements for each rotation practice, differences that exist between the two rotations, responses to applied N across different soils and different climatic conditions. It will also allow for the evaluation of tools used to adjust N application.
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker, John Lundvall
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker, John Lundvall
John E. Sawyer
This project is designed to study the N fertilization needs of continuous corn (C-C) and corn rotated with soybeans (C-S) as influenced by location and climate. Multiple rates of fertilizer N are spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will help determine N requirements for each rotational practice, differences that exist between the two rotations, and responses to applied N across different soils and different climatic conditions. It will also allow for the evaluation of tools used to adjust N …
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (SC) as influenced by location and climate. Multiple rates of fertilizer N were spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow the determination of N requirements for each rotation, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (SC) as influenced by location and climate. Multiple rates of fertilizer N were spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow the determination of N requirements for each rotation, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (SC) as influenced by location and climate. Multiple rates of fertilizer N are spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow the determination of N requirements for each rotation, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
Seasonal And Rotational Influences On Corn Nitrogen Requirements, John E. Sawyer, Daniel W. Barker
John E. Sawyer
This project was designed to study the N fertilization needs in continuous corn (CC) and corn rotated with soybean (SC) as influenced by location and climate. Multiple rates of fertilizer N are spring applied, with the intent to measure yield response to N within each rotation on a yearly basis for multiple years at multiple sites across Iowa. This will allow the determination of N requirements for each rotation practice, differences that exist between the two rotations, responses to applied N across different soils and climatic conditions, and evaluation of tools used to adjust N application.
Phosphorus And Potassium In Silage Harvest Of Drought-Damaged Corn, John E. Sawyer, Antonio P. Mallarino
Phosphorus And Potassium In Silage Harvest Of Drought-Damaged Corn, John E. Sawyer, Antonio P. Mallarino
John E. Sawyer
The dry conditions this summer are resulting in quite variable corn growth and production potential. Some livestock producers are beginning harvest of corn damaged by drought conditions for silage. Corn silage harvest results in more phosphorus (P) and potassium (K) removal than grain alone because almost the entire plant is harvested. The increased amount removed with silage differs for P and K because the relative amount of P and K is different in corn vegetative parts than in grain. For P there can be approximately four times greater amount of P per ton of dry matter in grain than vegetative …
Nitrogen Loss: How Does It Happen?, John E. Sawyer
Nitrogen Loss: How Does It Happen?, John E. Sawyer
John E. Sawyer
For the period April 1 through May 6, 2007, much of Iowa received more than 5 inches of rainfall (May 6, 2007 AWIS Inc. report). The Northwest, North-Central, and East-Central districts averaged slightly less than 5 inches, and the West-Central and Southwest districts more than 9 inches. With the large rainfall and flooding conditions, many producers are wondering about nitrogen (N) losses. While this period certainly has an influence on N in the soil, excessively wet conditions later in the spring are especially important for N losses. Early to mid-June will be a critical period to assess crop growth and …
Agronomic Options For Profitable Rice-Based Farming System In Northern Australia, Siva Sivapalan
Agronomic Options For Profitable Rice-Based Farming System In Northern Australia, Siva Sivapalan
Books & book chapters
Minimum air temperatures less than 15°C had biggest impact on varietal performance. Cold damage during the months of June and July warrants selection of varieties with cold tolerance for this environment, especially for the aerobic rice system. Ponded water has 4-8°C advantage over the air temperature, thus providing some protection against such cold damage. This has resulted in higher yields under flooded system. Planting dates, varying from late-February to late-May, were found to play a crucial role for plants to escape the low temperature damage at critical growth stages. Among the varieties tested, selected tropical varieties yielded higher than the …
The Illinois Soil Nitrogen Test: Should It Be Used In Iowa?, John E. Sawyer, Mohammod Ali Tabatabai
The Illinois Soil Nitrogen Test: Should It Be Used In Iowa?, John E. Sawyer, Mohammod Ali Tabatabai
John E. Sawyer
The test was developed several years ago at the University of Illinois by researchers in the Department of Natural Resources and Environmental Sciences. It is a laboratory procedure designed to measure N liberated from soil heated for 5 hours with dilute alkali solution (sodium hydroxide). The test does not measure nitrate, but does measure exchangeable ammonium and a fraction of soil organic N.
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
John E. Sawyer
Historically sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. The soil supply or combination from sources such as manure or precipitation has met crop S needs. However, soil S levels or supply will become depleted with prolonged crop removal, sulfate leaching, low precipitation deposition, and declining soil organic matter. The objective of this study was to determine the responsiveness of corn and soybean to S application (first year and residual second year) and S fertilizer material at multiple sites across Iowa soils and climatic conditions.
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
John E. Sawyer
Historically, sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. Soil supply or combination from sources such as manure or precipitation has met crop S needs. However, soil S levels or supply may become depleted with prolonged crop removal, sulfate leaching, low precipitation deposition, and declining soil organic matter. The objective of this study was to determine if corn and soybean yields would respond to S fertilizer rate and material at multiple sites across Iowa soils and climatic conditions.
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
John E. Sawyer
Historically sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. The soil supply or combination from sources such as manure or precipitation has met crop S needs. However, soil S levels or supply will become depleted with prolonged crop removal, sulfate leaching, low precipitation deposition, and declining soil organic matter. The objective of this study was to determine the responsiveness of corn and soybean to S application (first year and residual second year) and S fertilizer material at multiple sites across Iowa soils and climatic conditions.
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
John E. Sawyer
Historically sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. The soil supply or combination from sources such as manure or precipitation has met crop S needs. However, soil S levels or supply will become depleted with prolonged crop removal, sulfate leaching, low precipitation deposition, and declining soil organic matter. The objective of this study was to determine the responsiveness of corn and soybean to S application (first year and residual second year) and S fertilizer material at multiple sites across Iowa soils and climatic conditions.
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
John E. Sawyer
Historically, sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. Soil supply or combination from sources such as manure or precipitation has met crop S needs. However, soil S levels or supply may become depleted with prolonged crop removal, sulfate leaching, low precipitation deposition, and declining soil organic matter. The objective of this study was to determine if corn and soybean yields would respond to S fertilizer rate and material at multiple sites across Iowa soils and climatic conditions.
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
Sulfur Fertilizer Application To Corn And Soybean, John E. Sawyer, Daniel W. Barker
John E. Sawyer
Historically sulfur (S) application has not been recommended on Iowa soils for corn and soybean production. The soil supply or combination from sources such as manure or precipitation has met crop S needs. However, soil S levels or supply will become depleted with prolonged crop removal, sulfate leaching, low precipitation deposition, and declining soil organic matter. The objective of this study was to determine the responsiveness of corn and soybean to S application (first year and residual second year) and S fertilizer material at multiple sites across Iowa soils and climatic conditions.
Summary Of Sulfur Strip Trials Conducted In Central And Northeast Iowa Preliminary 2009 Results, John E. Sawyer, Daniel W. Barker, Brian J. Lang
Summary Of Sulfur Strip Trials Conducted In Central And Northeast Iowa Preliminary 2009 Results, John E. Sawyer, Daniel W. Barker, Brian J. Lang
John E. Sawyer
Sulfur (S) strip trials were conducted by ISU Extension field agronomists Brian Lang, George Cummins, and Mark Wuebker; Heartland Co-op; Innovative Ag; Five Star Co-op; Calcium Products, Inc; and cooperating growers.
Post-Plant Nitrogen Applications On Corn, John E. Sawyer
Post-Plant Nitrogen Applications On Corn, John E. Sawyer
John E. Sawyer
Has the wet weather interrupted planned nitrogen (N) fertilizer applications? What are the options if corn has emerged? All is not lost. In fact, in wet springs sidedress N can be an advantage because delayed application avoids potential losses and increases use by the crop.