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- Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research (12)
- Department of Agronomy and Horticulture: Faculty Publications (9)
- Nebraska Agricultural Experiment Station: Historical Circulars (4)
- Historical Research Bulletins of the Nebraska Agricultural Experiment Station (3)
Articles 1 - 28 of 28
Full-Text Articles in Agronomy and Crop Sciences
Optimizing Crop Productivity And Fertility Practices In Intermediate Wheatgrass, Roberta Bianchin Rebesquini
Optimizing Crop Productivity And Fertility Practices In Intermediate Wheatgrass, Roberta Bianchin Rebesquini
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The intensive management associated with many annual crops often includes recurring tillage, fertilization, and pesticide applications, which contribute to environmental concerns such as water pollution and soil erosion. Intermediate wheatgrass (Thinopyrum intermedium), recognized under the trade name Kernza®, is a perennial grass that can be managed to produce grain and biomass while providing desired environmental benefits such as soil conservation and nutrient cycling. There has been limited research on best management practices and crop productivity for this alternative dual-use crop in Nebraska. A field experiment was conducted beginning in 2021 to assess nitrogen (N), phosphorus (P), and potassium (K) management …
Evaluating Drill Interseeded Cover Crop Establishment And Nitrogen Impact In Irrigated Corn, Victor De Sousa Ferreira
Evaluating Drill Interseeded Cover Crop Establishment And Nitrogen Impact In Irrigated Corn, Victor De Sousa Ferreira
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The adoption of cover crops as a strategy to improve soil health and cropping systems sustainability is on the rise in the United States. PRE herbicides with soil residual activity are widely applied in corn production systems to prevent early season weed development, crop-weed competition, and yield loss. When preemergence herbicides are applied in the field, the active ingredients remain in the soil rhizosphere for a period of time, killing weed seedlings as they emerge. However, PRE herbicides can also impact the establishment of interseeded cover crops. Greenhouse bioassay was conducted to evaluate the preemergence herbicide carry-over potential to interseeded …
Plasticity Of Sorghum Biomass And Inflorescence Traits In Response To Nitrogen Application, Kyle M. Linders
Plasticity Of Sorghum Biomass And Inflorescence Traits In Response To Nitrogen Application, Kyle M. Linders
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Nitrogen is an essential nutrient required for growth and development in plants. Insufficient nitrogen availability can reduce vegetative growth and grain yield. However, nitrogen is a costly input for farmers, is energy intensive to manufacture, and runoff of excess nitrogen fertilizer impacts water quality. Compared to its close relative, maize, sorghum has much greater resilience to nitrogen and water deficit, and heat stress, allowing sorghum to be grown with fewer inputs and on marginal land. Variation in total biomass accumulation and grain yield between sorghum accessions, as well as between nitrogen conditions, can be largely explained by differences in vegetative …
Nitrification Inhibitor, Nitrogen Source, And Herbicide Effects On Soil Nitrogen Transformations And Corn Yield, William Neels
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 …
Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan Mcpherson
Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan 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 …
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
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
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 …
Benchmarking Impact Of Nitrogen Inputs On Grain Yield And Environmental Performance Of Producer Fields In The Western Us Corn Belt, Fatima A.M. Tenorio, Eileen L. Mclellan, Alison J. Eagle, Kenneth G. Cassman, Daryl Andersen, Marie Krausnick, Russell Oaklund, John Thorburn, Patricio Grassini
Benchmarking Impact Of Nitrogen Inputs On Grain Yield And Environmental Performance Of Producer Fields In The Western Us Corn Belt, Fatima A.M. Tenorio, Eileen L. Mclellan, Alison J. Eagle, Kenneth G. Cassman, Daryl Andersen, Marie Krausnick, Russell Oaklund, John Thorburn, Patricio Grassini
Department of Agronomy and Horticulture: Faculty Publications
Benchmarking crop yields against nitrogen (N) input levels can help provide opportunities to improve N ferti-lizer efficiency and reduce N losses on maize in the US Corn Belt by identifying fields most likely to benefit from improved N management practices. Here, we evaluated a large producer database that includes field-level data on yield and applied N inputs from 9280 irrigated and rainfed fields over a 7-year period (2009–2015) in Nebraska (USA). A spatial framework, based on technology extrapolation domains, was used to cluster each field into spatial units with similar climate and soil type that represent 1.3 million ha of …
Transforming Unmanned Aerial Vehicle (Uav) And Multispectral Sensor Into A Practical Decision Support System For Precision Nitrogen Management In Corn, Laura J. Thompson, Laila A. Puntel
Transforming Unmanned Aerial Vehicle (Uav) And Multispectral Sensor Into A Practical Decision Support System For Precision Nitrogen Management In Corn, Laura J. Thompson, Laila A. Puntel
Department of Agronomy and Horticulture: Faculty Publications
Determining the optimal nitrogen (N) rate in corn remains a critical issue, mainly due to unaccounted spatial (e.g., soil properties) and temporal (e.g., weather) variability. Unmanned aerial vehicles (UAVs) equipped with multispectral sensors may provide opportunities to improve N management by the timely informing of spatially variable, in-season N applications. Here, we developed a practical decision support system (DSS) to translate spatial field characteristics and normalized difference red edge (NDRE) values into an in-season N application recommendation. On-farm strip-trials were established at three sites over two years to compare farmer’s traditional N management to a split-application N management guided by …
Insufficient Nitrogen Supply From Symbiotic Fixation Reduces Seasonal Crop Growth And Nitrogen Mobilization To Seed In Highly Productive Soybean Crops, Nicolas Cafaro La Menza, Juan Pablo Monzon, John L. Lindquist, Timothy J. Arkebauer, Johannes M.H. Knops, Murray Unkovich, James E. Specht, Patricio Grassini
Insufficient Nitrogen Supply From Symbiotic Fixation Reduces Seasonal Crop Growth And Nitrogen Mobilization To Seed In Highly Productive Soybean Crops, Nicolas Cafaro La Menza, Juan Pablo Monzon, John L. Lindquist, Timothy J. Arkebauer, Johannes M.H. Knops, Murray Unkovich, James E. Specht, Patricio Grassini
Department of Agronomy and Horticulture: Faculty Publications
Nitrogen (N) supply can limit the yields of soybean [Glycine max (L.) Merr.] in highly productive environments. To explore the physiological mechanisms underlying this limitation, seasonal changes in N dynamics, aboveground dry matter (ADM) accumula- tion, leaf area index (LAI) and fraction of absorbed radiation (fAPAR) were compared in crops relying only on biological N2 fixation and available soil N (zero-N treatment) versus crops receiving N fertilizer (full-N treatment). Experiments were conducted in seven high-yield environments without water limitation, where crops received optimal management. In the zero-N treatment, biological N2 fixation was not sufficient to meet the N demand of …
Effects Of Different Water And Nitrogen Regimens On Yield Of Winter Wheat Produced In Nebraska, Joseph Emory Davis
Effects Of Different Water And Nitrogen Regimens On Yield Of Winter Wheat Produced In Nebraska, Joseph Emory Davis
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Wheat is the 3rd most prominent crop in the USA and approximately 50% is exported annually. Nebraska wheat production is 11th in the country, and it plays a major role in the state's agricultural economy, especially in western NE. Generally, wheat is grown under dryland conditions and the region grows much more wheat on unirrigated land than it does on irrigated. However, deficit irrigation has shown great value in producing high yielding wheat with much less water than needed for other crops. Finding new ways to leverage irrigation in wheat production may help address the need to produce food …
Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio
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 …
Understanding Nitrogen Limitation In Soybean, Nicolas Cafaro La Menza
Understanding Nitrogen Limitation In Soybean, Nicolas Cafaro La Menza
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Meeting soybean demand on existing cropland area for a global population of 9.7 billion people by the year 2050 requires narrowing the existing gap between average producer yield and yield potential. Soybean relies on two sources on nitrogen (N): biological N2 fixation and indigenous soil N supply. As soybean yield continues to increase, it seems critical to know if there is a yield level at which potential contribution of indigenous nitrogen sources and fixation becomes insufficient to meet crop N requirements for high yields, while still maintaining or increasing protein and oil concentration. This study evaluated N limitation across 29 …
Effects Of Nitrogen And Phosphorus Fertilizer And Topsoil Amendment On Native Plant Cover In Roadside Revegetation Projects, Heidi L. Hillhouse, Walter H. Schacht, Jonathan M. Soper, Carol E. Wienhold
Effects Of Nitrogen And Phosphorus Fertilizer And Topsoil Amendment On Native Plant Cover In Roadside Revegetation Projects, Heidi L. Hillhouse, Walter H. Schacht, Jonathan M. Soper, Carol E. Wienhold
Department of Agronomy and Horticulture: Faculty Publications
Establishing vegetation on roadsides following construction can be challenging, especially for relatively slow growing native species. Topsoil is generally removed during construction, and the surface soil following construction (“cut-slope soils”) is often compacted and low in nutrients, providing poor growing conditions for vegetation. Nebraska Department of Transportation (NDOT) protocols have historically called for nitrogen (N) and phosphorus (P) fertilization when planting roadside vegetation following construction, but these recommendations were developed for cool-season grass plantings and most current plantings use slower-establishing, native warmseason grasses that may benefit less than expected from current planting protocols. We evaluated the effects of nitrogen and …
Grain Sorghum Leaf Reflectance And Nitrogen Status, Akwasi A. Abunyewa, Richard B. Ferguson, Charles S. Wortmann, Stephen C. Mason
Grain Sorghum Leaf Reflectance And Nitrogen Status, Akwasi A. Abunyewa, Richard B. Ferguson, Charles S. Wortmann, Stephen C. Mason
Department of Agronomy and Horticulture: Faculty Publications
Nitrogen deficiency is a common but readily managed constraint to grain yield. A quick and nondestructive detection of crop N status using remote sensing could be a means to increased N use efficiency. Research was conducted in a greenhouse in 2006 at the University of Nebraska-Lincoln to establish the relationship of spectral reflectance with N status in leaves of grain sorghum, to develop indices for interpretation of the results and to predict chlorophyll content. Nitrogen stress decreased chlorophyll meter reading and leaf N content, but increased leaf and canopy reflectance. The SPAD values were significantly increased by both water and …
Nutrients In The Nexus, Eric A. Davidson, Rachel L. Nifong, Richard B. Ferguson, Cheryl Palm, Deanna L. Osmond, Jill S. Baron
Nutrients In The Nexus, Eric A. Davidson, Rachel L. Nifong, Richard B. Ferguson, Cheryl Palm, Deanna L. Osmond, Jill S. Baron
Department of Agronomy and Horticulture: Faculty Publications
Synthetic nitrogen (N) fertilizer has enabled modern agriculture to greatly improve human nutrition during the twentieth century, but it has also created unintended human health and environmental pollution challenges for the twentyfirst century. Averaged globally, about half of the fertilizer-N applied to farms is removed with the crops, while the other half remains in the soil or is lost from farmers’ fields, resulting in water and air pollution. As human population continues to grow and food security improves in the developing world, the dual development goals of producing more nutritious food with low pollution will require both technological and socioeconomic …
Nitrogen And Water Effects On Canopy Sensor Measurements For Site-Specific Management Of Crops, Nicholas C. Ward
Nitrogen And Water Effects On Canopy Sensor Measurements For Site-Specific Management Of Crops, Nicholas C. Ward
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Water and nitrogen (N) are undoubtedly the two largest agricultural inputs globally. Coupled with advances in site-specific management technology their integration into production agriculture will allow for the most efficient use these crop input resources. Active canopy sensors offer the ability to measure biophysical plant traits rapidly and make assessments about plant status. Specifically, optical sensor measurements of light reflectance assess plant N status allowing for in-season and on-the-go N recommendations and applications; while infrared thermometers (IRT) measurement of canopy temperature can be used a tool for irrigation management. To evaluate how these technologies work among different plant stress environments …
Remote Estimation Of Nitrogen And Chlorophyll Contents In Maize At Leaf And Canopy Levels, Michael Schlemmer, Anatoly A. Gitelson, James S. Schepers, Richard B. Ferguson, Y. Peng, J. Shanahan, Donald Rundquist
Remote Estimation Of Nitrogen And Chlorophyll Contents In Maize At Leaf And Canopy Levels, Michael Schlemmer, Anatoly A. Gitelson, James S. Schepers, Richard B. Ferguson, Y. Peng, J. Shanahan, Donald Rundquist
Department of Agronomy and Horticulture: Faculty Publications
Leaf and canopy nitrogen (N) status relates strongly to leaf and canopy chlorophyll (Chl) content. Remote sensing is a tool that has the potential to assess N content at leaf, plant, field, regional and global scales. In this study, remote sensing techniques were applied to estimate N and Chl contents of irrigated maize (Zea mays L.) fertilized at five N rates. Leaf N and Chl contents were determined using the red-edge chlorophyll index with R2 of 0.74 and 0.94, respectively. Results showed that at the canopy level, Chl and N contents can be accurately retrieved using green and red-edge Chl …
High Yield Soybean Management: Planting Practices, Nutrient Supply, And Growth Modification, Evan Sonderegger
High Yield Soybean Management: Planting Practices, Nutrient Supply, And Growth Modification, Evan Sonderegger
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Growers are constantly seeking ways to improve yield in soybean [Glycine max (L.) Merr.]. There has been much interest in the use of selected alternative practices to maximize soybean yield. These practices include planting soybean at higher than recommended seeding rates, planting soybean in narrow rows, breaking apical dominance to induce branching, application of strobilurin fungicides prophylactically to minimize disease and extend the seed filling period, the use of N fertilizer both in furrow and foliar applied, and the use of seed treatments to promote early stand establishment and health. Field studies were conducted at the University of Nebraska …
A Review Of Cover Crops For Eastern Nebraska, Tyler Williams
A Review Of Cover Crops For Eastern Nebraska, Tyler Williams
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The focus of this project is two fold, first to provide a short literature review of cover crops (CC) and then discuss the results from a field experiment that was designed to evaluate the nitrogen contribution from cover crop mixes to the subsequent corn crop. The literature review will focus on the aspects of CC that are related to the field of study. Cover crops, as defined by the United States Department of Agriculture (USDA) are crops that are agronomically sound and grown for the purpose of erosion control or other objectives related to conservation or soil improvement. Cover crops …
An Integrated Crop- And Soil-Based Strategy For Variable-Rate Nitrogen Management In Corn, Darrin F. Roberts
An Integrated Crop- And Soil-Based Strategy For Variable-Rate Nitrogen Management In Corn, Darrin F. Roberts
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Nitrogen (N) management in cereal crops has been the subject of considerable research and debate for several decades. Historic N management practices have contributed to low nitrogen use efficiency (NUE). Low NUE can be caused by such things as poor synchronization between soil N supply and crop demand, uniform application rates of fertilizer N to spatially variable landscapes, and failure to account for temporally variable influences on soil N supply and crop N need. Active canopy reflectance sensors and management zones (MZ) have been studied separately as possible plant- and soil-based N management tools to increase NUE. Recently, some have …
Influence Of Fertilizer Nitrogen And Sulfur On Production Of Malting Barley, G. W. Rehm, R. S. Moomaw
Influence Of Fertilizer Nitrogen And Sulfur On Production Of Malting Barley, G. W. Rehm, R. S. Moomaw
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
Studies in north-central Nebraska from 1975 through 1977: 1. Evaluated the malting barley production potential of the irrigated sandy soils of the region. 2. Measured the effect of application of N and S on yield and quality of barley grown for malting purposes. 3. Investigated the ability of N analysis of barley in the vegetative stage to predict protein content of grain at harvest. Data gathered lead to the following conclusions: 1. The potential for production of malting barley on irrigated sandy soils of north-central Nebraska is limited. 2. Yields increased with the application of fertilizer N throughout the study …
Effects Of No-Tillage Fallow As Compared To Conventional Tillage In A Wheat-Fallow System, C. R. Fenster, G. A. Peterson
Effects Of No-Tillage Fallow As Compared To Conventional Tillage In A Wheat-Fallow System, C. R. Fenster, G. A. Peterson
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
The benefits of reducing tillage by use of herbicides for weed control emphasizes why research was started to study a fallow system where all tillage was replaced by herbicides. Wheat planting was then the only soil disturbing operation. Objectives of the research were to compare the effects of no-tillage (chemical), stubble-mulch and plow (bare fallow) systems of fallow on: 1. Grain yield. 2. Grain protein. 3. Residue retention. 4. Soil nitrate-nitrogen accumulation. 5. Soil water accumulations during fallow. Data presented are in the form of a progress report. These experiments will continue.
The Effect Of 2,4-D, Grazing Management And Nitrogen Fertilizer On Pasture Production, M. K. Mccarty, M. L. Cox, D. L. Linscott
The Effect Of 2,4-D, Grazing Management And Nitrogen Fertilizer On Pasture Production, M. K. Mccarty, M. L. Cox, D. L. Linscott
Historical Research Bulletins of the Nebraska Agricultural Experiment Station
Many pastures in eastern Nebraska and surrounding areas have gradually decreased in productivity. Over a long period of heavy grazing, native warm-season grasses have been largely replaced with Kentucky bluegrass, other less desirable grasses, and broadleaf weeds. A program was started in 1949 to study the effectiveness of protection from grazing in changing the botanical composition and yield of a pasture where the predominant forage was Kentucky bluegrass. Several weed control treatments were included in this experiment to determine if mowing or spraying would hasten the return of more desirable forage. After weed control and differential grazing treatments had been …
Symptoms And Control Of Zinc Deficiency In Corn, F. V. Pumphrey, F. E. Koehler
Symptoms And Control Of Zinc Deficiency In Corn, F. V. Pumphrey, F. E. Koehler
Nebraska Agricultural Experiment Station: Historical Circulars
The purpose of this publication is to describe zinc deficiency symptoms in corn and to present recommendations for applications of zinc fertilizer.
Answers To Questions About Partridge Pea, T. H. Goodding, J. C. Russel
Answers To Questions About Partridge Pea, T. H. Goodding, J. C. Russel
Nebraska Agricultural Experiment Station: Historical Circulars
The Nebraska Agricultural Experiment Station has been working with partridge pea since 1944. Seed has been distributed for tests, and several farmers are now growing it. It is primarily a plant for soil conservation and soil improvement. Its value in comparison with other legumes have not been fully established.
Fertilization And Improvement Of Native Subirrigated Meadows In Nebraska, P. Ehlers, G. Viehmeyer, R. Ramig, E. M. Brouse
Fertilization And Improvement Of Native Subirrigated Meadows In Nebraska, P. Ehlers, G. Viehmeyer, R. Ramig, E. M. Brouse
Nebraska Agricultural Experiment Station: Historical Circulars
It is the purpose of this circular to summarize the 1948-51 results of fertilizer applications upon subirrigated native meadows. It is upon these lands that the cattleman depends to a large extent for winter feed.
Microorganisms And Their Effects On Crops And Soils, T. M. Mccalla, T. H. Goodding
Microorganisms And Their Effects On Crops And Soils, T. M. Mccalla, T. H. Goodding
Nebraska Agricultural Experiment Station: Historical Circulars
Many of the cropping and tillage practices that a farmer uses are effective in crop productivity because of their influence on microbial activity.