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Full-Text Articles in Agronomy and Crop Sciences

Large-Scale Dryland Cropping Systems, A. Schlegel, L. Haag, A. Burnett Jan 2020

Large-Scale Dryland Cropping Systems, A. Schlegel, L. Haag, A. Burnett

Kansas Agricultural Experiment Station Research Reports

This study was conducted from 2008–2019 at the Kansas State University Southwest Research- Extension Center near Tribune, KS. The purpose of the study was to identify whether more intensive cropping systems can enhance and stabilize production in rainfed cropping systems to optimize economic crop production, more efficiently capture and utilize scarce precipitation, and maintain or enhance soil resources and environmental quality. The crop rotations evaluated were continuous grain sorghum (SS), wheat-fallow (WF), wheat-corn-fallow (WCF), wheat-sorghum-fallow (WSF), wheat-corn-sorghum-fallow (WCSF), and wheat-sorghum-corn-fallow (WSCF). All rotations were grown using no-tillage practices except for WF, which was grown using reduced-tillage. The efficiency of precipitation …


Southwest Research-Extension Center Field Day 2020 Jan 2020

Southwest Research-Extension Center Field Day 2020

Kansas Agricultural Experiment Station Research Reports

Report of agricultural research from southwest Kansas, published 2020.


2018–2019 Precipitation Data, Mary Knapp Jan 2020

2018–2019 Precipitation Data, Mary Knapp

Kansas Agricultural Experiment Station Research Reports

Precipitation data for Kansas Agricultural Experiment Stations and fields, 2018-2019.


Long-Term Effect Of Tillage Practices And Nitrogen Fertilization On Corn Yield, Carlos A. Bonini Pires, Marcos M. Sarto, James S. Lin, William G. Davis, Charles Rice Jan 2020

Long-Term Effect Of Tillage Practices And Nitrogen Fertilization On Corn Yield, Carlos A. Bonini Pires, Marcos M. Sarto, James S. Lin, William G. Davis, Charles Rice

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to investigate the effect of different tillage systems and nitrogen (N) fertilizers on corn yield. Higher corn yields (207 bu/a and 203 bu/a) were found under no-tillage + high (150 lb N/a) manure application, and tillage + super high manure (750 lb N/a), respectively. The trend observed for the different nitrogen fertilizers between tillage systems was the same. However, a greater corn yield was observed under no-till in comparison to tilled conditions for both high fertilizer and high manure. No-till improves soil water infiltration, aggregation, nutrient cycling, and may increase crop yield. On other …


Occasional Tillage And Nitrogen Application Effects On Winter Wheat And Grain Sorghum Yield, Augustine K. Obour, John D. Holman, Alan J. Schlegel Jan 2020

Occasional Tillage And Nitrogen Application Effects On Winter Wheat And Grain Sorghum Yield, Augustine K. Obour, John D. Holman, Alan J. Schlegel

Kansas Agricultural Experiment Station Research Reports

Occasional tillage ahead of winter wheat planting could alleviate herbicide-resistant weeds, redistribute soil acidification, and improve seedbed at wheat planting. The objec­tive of this study was to determine occasional tillage and nitrogen (N) fertilizer ap­plication effects on winter wheat, and grain sorghum yields and soil quality in a wheat-sorghum-fallow cropping system. Treatments were three tillage practices: 1) continuous no-tillage (NT); 2) continuous reduced-tillage (RT); and 3) single tillage operation every 3 years (June-July) ahead of winter wheat planting [occasional tillage (OT)]. The sub-plot treatments were assigned to four N fertilizer rates (0, 40, 80, and 120 lb/a of N). Results …


Response To Mixing Wheat Seed With Fertilizer In The Drill At Planting, C. Weber, D. A. Ruiz Diaz Jan 2020

Response To Mixing Wheat Seed With Fertilizer In The Drill At Planting, C. Weber, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

Mixing dry phosphorus (P) fertilizer with winter wheat seed is common in Kansas to provide a starter fertilizer benefit to the crop. This study was designed to evaluate the effects of dry P sources, rates, and times fertilizer mixed with wheat seed, effects on early growth and overall productivity and yield of the crop. Two winter wheat studies were conducted in the 2018–2019 wheat growing season at Manhattan (site 1) and Topeka (site 2) Kansas. The previous crop for site 1 was soybean and corn at site 2. The winter wheat was no-till drilled at 70 lb/a and mixed with …


Dynamics Of Post-Flowering Nitrogen Uptake And Nitrogen Recovery Efficiency Using 15n Isotope Labeling In Corn, J. A. Fernandez, J. B. Nippert, I. A. Ciampitti Jan 2020

Dynamics Of Post-Flowering Nitrogen Uptake And Nitrogen Recovery Efficiency Using 15n Isotope Labeling In Corn, J. A. Fernandez, J. B. Nippert, I. A. Ciampitti

Kansas Agricultural Experiment Station Research Reports

In corn (Zea maysL.), breeding and selection for grain yield over time has been accom­panied by a simultaneous increase in plant nitrogen (N) uptake. The understanding of plant N dynamics has attracted attention due to the environmental concerns related to N losses coming from fertilization. This research study was implemented to 1) describe N uptake and allocation dynamics, and 2) quantify fertilizer recovery efficiency across late-N strategies. Two field experiments (one under irrigation and one rainfed) were conducted at the Ashland Bottoms Research Farm, KS, during 2017. Three hybrids with different year of release and three N scenarios …


Tiller Contributions To Low-Density Corn Biomass And Yield, R. Veenstra, C. Messina, L. Haag, P. V. Vara Prasad, I. A. Ciampitti Jan 2020

Tiller Contributions To Low-Density Corn Biomass And Yield, R. Veenstra, C. Messina, L. Haag, P. V. Vara Prasad, I. A. Ciampitti

Kansas Agricultural Experiment Station Research Reports

Tillers (commonly termed “suckers”) have lower overall yield contributions in corn (Zea maysL.) than in other Poaceae species. Current research evaluating the value of tillers in corn is scarce, particularly under water-limited conditions. This study aims to quantify relationships between tiller, main plant, and full (considering both tiller and main plant fractions) plant aboveground biomass and yields of corn under low plant density scenarios. Experiments were conducted in the 2019 growing season at three sites across Kansas (Garden City, Goodland, and Manhattan) evaluating two tiller-prone corn hybrids common in this region (P0805AM and P0657AM) at two plant densities …


Corn Yield Response To Nitrogen In North-Central Kansas, A. A. Correndo, I. A. Ciampitti Jan 2020

Corn Yield Response To Nitrogen In North-Central Kansas, A. A. Correndo, I. A. Ciampitti

Kansas Agricultural Experiment Station Research Reports

The aim of this study was to evaluate the response of corn (Zea maysL.) grain yield to nitrogen (N) fertilizer. During the 2019 cropping season, an N rate experiment in corn was established in Scandia, KS, evaluating five N fertilizer rates as UAN (28-0-0) under both dryland and irrigated conditions. Average yields ranged from 138 to 236 bu/a under rainfed and from 153 to 249 bu/a for irrigated conditions. Under both dryland and irrigated conditions, maximum yields were achieved with an N rate of about 161 lb/a. Total N supply was calculated as N at planting plus fertilizer …


Efficacy Of Late-Season Herbicide Programs For Controlling Palmer Amaranth In Postharvest Wheat Stubble, R. Liu, V. Kumar, N. Aquilina, T. Lambert Jan 2020

Efficacy Of Late-Season Herbicide Programs For Controlling Palmer Amaranth In Postharvest Wheat Stubble, R. Liu, V. Kumar, N. Aquilina, T. Lambert

Kansas Agricultural Experiment Station Research Reports

Late-season control of Palmer amaranth in wheat stubble is a challenge for Kansas producers. The objective of this study was to determine the effectiveness of POST herbicide programs (with multiple modes of actions) for late-season control of Palmer amaranth in postharvest wheat stubble. The study was conducted at the Kansas State University Agricultural Research Center in Hays, KS, in 2019. The study site had a natural seedbank of Palmer amaranth that emerged immediately after wheat harvest. All selected herbicide programs were tested 3 weeks after wheat harvest, when Palmer amaranth plants had attained a height of 2 to 2.5 feet …


Response Of Kansas Feral Rye Populations To Aggressor Herbicide And Management In Coaxium Wheat Production System, V. Kumar, R. Liu, T. Lambert Jan 2020

Response Of Kansas Feral Rye Populations To Aggressor Herbicide And Management In Coaxium Wheat Production System, V. Kumar, R. Liu, T. Lambert

Kansas Agricultural Experiment Station Research Reports

Feral rye (Secale cerealeL.), also commonly known as cereal or volunteer rye, is a trou­blesome winter annual grass weed species in wheat producing regions of the United States, including Kansas. Lack of effective herbicide options complicates the selective control of feral rye in winter wheat. The main objectives of this research were (1) to determine the response of 10 feral rye populations collected from central Kansas wheat fields to Aggressor herbicide in dose-response assays, and (2) to evaluate the effective­ness of Aggressor herbicide for feral rye control in CoAXium winter wheat in Kansas. Dose-response assays indicated that all …


Saline Experimental Range Dormant Season Wildfire: Short-Term Effect On Forage Production And Plant Composition, Keith R. Harmoney Jan 2020

Saline Experimental Range Dormant Season Wildfire: Short-Term Effect On Forage Production And Plant Composition, Keith R. Harmoney

Kansas Agricultural Experiment Station Research Reports

Rangeland wildfires in the southern plains may occur any time of year, but the low hu­midity, increasing temperatures, and dry and abundant fuel load of late winter and early spring can result in greater wildfire occurrence and severity. Fires that occur before the growing season remove standing residual vegetation and greatly reduce litter cover, so the soil surface may be left bare for several weeks or months before the onset of new pas­ture growth. Exposure of plant buds to cold temperatures during dormancy, soil water evaporation, and soil crusting from the force of falling precipitation and puddling may lead to …


Using Modified Intensive Early Stocking For Cow/Calf Production, Keith R. Harmoney, John R. Jaeger Jan 2020

Using Modified Intensive Early Stocking For Cow/Calf Production, Keith R. Harmoney, John R. Jaeger

Kansas Agricultural Experiment Station Research Reports

Intensive early stocking (IES) was introduced nearly a half century ago in eastern Kan­sas and has since been adopted as a major management tool to increase animal produc­tion, efficiency of production, and economic return on tallgrass rangelands. These in­creases have come almost exclusively by using IES with young stocker animals. Intensive early stocking and its gains have been proven effective repeatedly in published research. A similar modified IES (MIES) system has increased production efficiency of stocker animals on western Kansas rangelands. Perennial grassland acres for cattle produc­tion, as well as cattle numbers, are declining. Using management practices that mimic the …


Timing Of Side-Dress Applications Of Nitrogen For Corn In Conventional And No-Till Systems, D. W. Sweeney, D. Ruiz Diaz Jan 2020

Timing Of Side-Dress Applications Of Nitrogen For Corn In Conventional And No-Till Systems, D. W. Sweeney, D. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

Corn yield and yield components were affected by tillage and nitrogen (N) side-dress application options in 2019. Average corn yields were 15% greater with conventional tillage than with no-till. Yields were improved by either splitting N rate between pre-plant and side-dress at the V10 growth stage or adding additional side-dress N as compared with applying 150 lb/a pre-plant.


Evaluation Of Planting Technologies In Winter Canola, M. A. Secchi, Y. Wright, C. Foster, M. J. Stamm, I. A. Ciampitti Jan 2020

Evaluation Of Planting Technologies In Winter Canola, M. A. Secchi, Y. Wright, C. Foster, M. J. Stamm, I. A. Ciampitti

Kansas Agricultural Experiment Station Research Reports

Winter canola (Brassica napusL.) stand establishment and winter survival are two of the most important limitations to canola production faced by farmers. We hypothesize that planting canola with a system that provides accurate in-row spacing will positively impact crop establishment, survivability, and reduce seed input costs. A planting system that provides a homogenous spatial and temporal distribution of canola plants will also positively affect yield. The objective of this study was to investigate the impact of three metering systems with different opener and seed delivery systems on stand establish­ment, spatial distribution, and yield at three seeding densities and …


Physiological Changes Across Historical Sorghum Hybrids Released During The Last Six Decades, P. A. Demarco, L. Mayor, S. Tamagno, J. A. Fernandez, P. V. Vara Prasad, J. L. Rotundo, C. D. Messina, I. A. Ciampitti Jan 2020

Physiological Changes Across Historical Sorghum Hybrids Released During The Last Six Decades, P. A. Demarco, L. Mayor, S. Tamagno, J. A. Fernandez, P. V. Vara Prasad, J. L. Rotundo, C. D. Messina, I. A. Ciampitti

Kansas Agricultural Experiment Station Research Reports

For the last decades, sorghum (Sorghum bicolorL. Moench) improvement in the United States (US) has been related to targeted modifications in genotype, environ­ment, and management (G × E × M) combinations. Retrospective studies are relevant to document changes in the phenotype associated to breeding process and to explore alternatives to improve yield and its physiological associated traits. This study aims to characterize yield changes over time for hybrids with different year of release. Field trials were conducted during 2018 and 2019 growing seasons in eight environments/site-years across the states of Kansas and Texas including 20 grain sorghum hybrids …


An Efficient Stocking Strategy For Grazing Replacement Heifers, Keith R. Harmoney, John R. Jaeger Jan 2020

An Efficient Stocking Strategy For Grazing Replacement Heifers, Keith R. Harmoney, John R. Jaeger

Kansas Agricultural Experiment Station Research Reports

Even though Kansas native rangelands often have steep slopes or shallow soils not con­ducive to many other uses other than livestock grazing, native rangeland and perennial grassland acres in Kansas have been declining. Cropland acreage over this same time frame has increased, and rangelands have also become more fragmented by small ranch­ettes and urbanization. Producers may be looking to increase production efficiency on a shrinking forage land base. The use of intensive early stocking (IES) is one of the most efficient stocking strategies to produce beef on rangeland acres. The IES strategy has been widely used in eastern Kansas and …


Long-Term Cover Crop Management Effects On Soil Health In Semiarid Dryland Cropping Systems, L. M. Simon, A. K. Obour, J. D. Holman, K. L. Roozeboom Jan 2020

Long-Term Cover Crop Management Effects On Soil Health In Semiarid Dryland Cropping Systems, L. M. Simon, A. K. Obour, J. D. Holman, K. L. Roozeboom

Kansas Agricultural Experiment Station Research Reports

Growing cover crops (CC) in semiarid drylands may provide benefits to soil health. This study examined long-term CC management effects in a no-till winter wheat-grain sorghum-fallow cropping system in southwest Kansas. Objectives were to assess the impacts of CCs on 1) soil organic carbon (SOC) and nitrogen (N) stocks, 2) soil susceptibility to erosion, as well as to 3) quantify the effects of haying cover crops as annual forages. Treatments were spring-planted and included peas for grain as well as one-, three-, and six-species CC mixtures of oats, triticale, peas, buckwheat, turnips, and radishes compared with conventional chemical-fallow. Half of …


Kansas Fertilizer Research 2020, D. A. Ruiz Diaz Jan 2020

Kansas Fertilizer Research 2020, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

A summary of research conducted in 2018-2020 on fertilizer use and management practices for crops in Kansas. Published in 2020 from the Kansas State University Agricultural Experiment Station and Cooperative Extension Servicehttps://www.ag.k-state.edu/.


Water Use And Productivity Of Teff, A Dairy Quality Forage Crop, J. M. Davidson, R. M. Aiken, D. H. Min, G. J. Kluitenberg Jan 2020

Water Use And Productivity Of Teff, A Dairy Quality Forage Crop, J. M. Davidson, R. M. Aiken, D. H. Min, G. J. Kluitenberg

Kansas Agricultural Experiment Station Research Reports

Teff grass can be a competitive summer annual forage in Kansas. Teff grass is a rapidly growing, high quality forage that could be a good option for producers in water-limited areas with a short growing season. The cultivar ‘Excalibur’ exhibited superior biomass (4280 lb/a) and crop water productivity (610 lb/a-in.), among teff cultivars. This study also indicated that biomass productivity and crop water productivity of sorghum sudangrass (696 lb/a-in.) tended to be greater than that of forage pearl millet (528 lb/a-in.). Further research into teff grass should focus on integration of teff into irrigation management systems with restricted water supply.


Cation Exchange Resins As Indicator Of In-Season Potassium Supply For Soybean In Kansas, D. A. Charbonnier, M. J. Coelho, D. A. Ruiz Diaz Jan 2020

Cation Exchange Resins As Indicator Of In-Season Potassium Supply For Soybean In Kansas, D. A. Charbonnier, M. J. Coelho, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

The use of ion-exchange resins to measure soil nutrient availability has potential applications for fertilizer recommendations. The objective of this study was to evaluate the relationship between potassium (K) adsorption by cation exchange resins (CER) and K uptake by soybean in field conditions. The study was conducted at two locations in Kansas during 2019. Two treatments were selected to evaluate the CER. Treatments included a check (0 lb K2O/a) and a high K rate with 150 lb K2O/a applied pre-plant and incorporated. The Plant Root Simulator (PRS, Western Ag Innovations, Saskatchewan, Canada) was used as an …


Including Legumes In Bermudagrass Pastures, J. L. Moyer, L. W. Lomas Jan 2020

Including Legumes In Bermudagrass Pastures, J. L. Moyer, L. W. Lomas

Kansas Agricultural Experiment Station Research Reports

Bermudagrass is a productive forage species when intensively managed. However, it has periods of dormancy and requires proper management to maintain forage quality. Legumes in a bermudagrass sward could improve forage quality and reduce fertilizer usage; however, legumes are difficult to establish and maintain with the competitive grass. Clovers can maintain survival once established in bermudagrass sod, and may be productive enough to substitute for some N fertilization. This study was designed to compare dry cow performance on a bermudagrass pasture system that included ladino and crimson clovers (Legume) vs. bermudagrass alone (Nitrogen). Use of legumes in wheat-bermudagrass pastures did …


Wheat Grain Yield And Protein Concentration Response To Nitrogen And Sulfur Rates, Brent R. Jaenisch, Tara Wilson, Nathan O. Nelson, Mary Guttieri, Romulo P. Lollato Jan 2020

Wheat Grain Yield And Protein Concentration Response To Nitrogen And Sulfur Rates, Brent R. Jaenisch, Tara Wilson, Nathan O. Nelson, Mary Guttieri, Romulo P. Lollato

Kansas Agricultural Experiment Station Research Reports

Winter wheat is often double-cropped after soybeans in no-tillage systems. The soybean crop removes large quantities of sulfur (S), which might cause S deficiency for the following wheat crop. Our objective was to evaluate the responses of three wheat varieties to three nitrogen (N) and four S fertilizer rates representing a range of N:S ratios. The experiment was conducted near Ashland Bottoms and Hutchinson, KS. Treatments were arranged as a complete factorial structure with a split-split-plot design. Variety was the whole-plot, N was the sub-plot, and S was the sub-sub plot. Nitrogen rates were 50, 100, and 150% of the …


Relationships Between The Haney H3a And Conventional Soil Tests For Phosphorus And Potassium In Kansas Soils, E. B. Rutter, D. A. Ruiz Diaz Jan 2020

Relationships Between The Haney H3a And Conventional Soil Tests For Phosphorus And Potassium In Kansas Soils, E. B. Rutter, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

The Haney H3A soil test procedure has gained popularity in recent years for soil health evaluation and has been used in some circles to adjust fertilizer management practices. However, data relating this test to current soil tests, relative crop yield, or total nutrient uptake are nonexistent in Kansas soils. The objective of this study is to evaluate the correlation between H3A soil test phosphorus (P) and potassium (K) with soil tests currently used in Kansas (e.g. Mehlich-3). Soils from a nitrogen response study were extracted using both Mehlich-3 and H3A (version 4) soil test procedures. Mehlich-3 and Haney extractable P …


Roundup 2020: Agricultural Research Center - Hays Jan 2020

Roundup 2020: Agricultural Research Center - Hays

Kansas Agricultural Experiment Station Research Reports

Roundup is the major beef cattle education and outreach event sponsored by the Agricultural Research Center - Hays. The 2020 program is the 106th staging of Roundup. The purpose is to communicate timely, applicable research information to producers and extension personnel.


Dual Use Of Cover Crops For Forage Production And Soil Health In Dryland Crop Production, A. K. Obour, J. D. Holman, L. M. Simon, S. K. Johnson Jan 2020

Dual Use Of Cover Crops For Forage Production And Soil Health In Dryland Crop Production, A. K. Obour, J. D. Holman, L. M. Simon, S. K. Johnson

Kansas Agricultural Experiment Station Research Reports

Integrating a cover crop (CC) into dryland crop production in the semiarid central Great Plains (CGP) can provide several ecosystem benefits. However, CC adoption is slow and not widely popular in the CGP because CCs utilize water that other­wise would be available for the subsequent cash crop. Grazing or haying CCs can provide economic benefits to offset revenue loss associated with decreased crop yields when CCs are grown ahead of a cash crop. Objectives of the current research were to 1) determine forage production of CC mixtures, and 2) evaluate the impacts of removing CCs for forage on subsequent crop …


Soil Phosphorus Fractions After Long-Term Fertilizer Placement In Different Kansas Soils, M. J. Coelho, D. A. Ruiz Diaz Jan 2020

Soil Phosphorus Fractions After Long-Term Fertilizer Placement In Different Kansas Soils, M. J. Coelho, D. A. Ruiz Diaz

Kansas Agricultural Experiment Station Research Reports

Phosphorus (P) fertilizer placement can affect the long-term dynamics and forms of P, and the overall soil P pools. These changes can vary by soil type, and affect P uptake and use efficiency by crops. The objective of this study was to evaluate the changes in the labile P fractions in three Kansas soil types under P fertilizer placements (broadcast versus deep band) after ten years of crop rotation. Three field studies were conducted at Scandia, Ottawa, and Manhattan. Three treatments were evaluated: 1) a control with no P fertilizer application and two fertilizer treatments (80 lb P2O …


Investigating The Use Of Unmanned Aerial Vehicles And High-Resolution Multispectral Imagery To Characterize Grain Sorghum Senescence Patterns, I. H. Barnhart, L. Mayor, I. A. Ciampitti Jan 2020

Investigating The Use Of Unmanned Aerial Vehicles And High-Resolution Multispectral Imagery To Characterize Grain Sorghum Senescence Patterns, I. H. Barnhart, L. Mayor, I. A. Ciampitti

Kansas Agricultural Experiment Station Research Reports

Grain sorghum is important to producers around the world. In precipitation-limited environments, sorghum is the grain of choice because it is able to produce grain yields with limited precipitation. Plant breeders place a priority on breeding for a characterized form of post-flowering drought-tolerance, known as stay-green (SG). Assessing thousands of plots for this trait can be labor intensive and time consuming, so the goal of this study was to use unmanned aircraft vehicles (UAVs) equipped with high resolution cameras to characterize and quantify senescence patterns in grain sorghum. A field experiment with 20 hybrids was planted in Manhattan, KS. The …


Response Of Dicamba/Fluroxypyr/Glyphosate-Resistant Kochia To Atrazine And Alternative Postemergence Herbicides, R. Liu, V. Kumar, R. Currie, P. W. Geier, T. Lambert, P. W. Stahlman Jan 2020

Response Of Dicamba/Fluroxypyr/Glyphosate-Resistant Kochia To Atrazine And Alternative Postemergence Herbicides, R. Liu, V. Kumar, R. Currie, P. W. Geier, T. Lambert, P. W. Stahlman

Kansas Agricultural Experiment Station Research Reports

Two kochia accessions (KS-4A and KS-4H) were previously identified from a corn field near Garden City, KS, with multiple resistance to glyphosate (Roundup PowerMax), dicamba (Clarity), and fluroxypyr (Starane Ultra). The objectives of this research were to (1) determine the response of these kochia accessions to preemer­gence (PRE) and postemergence (POST) applied atrazine (Aatrex) in dose-response assays, and (2) determine the effectiveness of alternative POST herbicides. Seeds of a known susceptible kochia accession (SUS) collected from research fields in Hays, KS, were used for comparison. Greenhouse experiments were conducted at the Kansas State University Agricultural Research Center near Hays, KS, …


Long-Term Nitrogen And Phosphorus Fertilization Of Irrigated Corn, Alan J. Schlegel, H. Dewayne Bond Jan 2020

Long-Term Nitrogen And Phosphorus Fertilization Of Irrigated Corn, Alan J. Schlegel, H. Dewayne Bond

Kansas Agricultural Experiment Station Research Reports

Long-term research shows that phosphorus (P) and nitrogen (N) fertilizer must be applied to optimize production of irrigated corn in western Kansas. In 2019, N applied alone increased yields by 71 bu/a, whereas P applied alone increased yields by 10 bu/a. Nitrogen and P applied together increased yields up to 131 bu/a, which is 10 bu/a less than the 10-year average of 141 bu/a. Application of 120 lb/a N (with highest P rate) produced 97% of maximum yield in 2019, which is slightly greater than the 10-year average. Application of 80 instead of 40 lb P2O5/a …