Agricultural Science Commons^™

Open Field Host Selection And Behavior By Tamarisk Beetles (Diorhabda Spp.) (Coleoptera: Chrysomelidae) In Biological Control Of Exotic Saltcedars (Tamarix Spp.) And Risks To Non-Target Athel (T. Aphylla) And Native Frankenia Spp., Patrick J. Moran, C. Jack Deloach, Tom L. Dudley, Joaquin Sanabria

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Biological control of invasive saltcedars (Tamarix spp.) in the western U.S. by exotic tamarisk leaf beetles, Diorhabda spp., first released in 2001 after 15 years of development, has been successful. In Texas, beetles from Crete, Greece were first released in 2004 and are providing control. However, adults alight, feed and oviposit on athel (Tamarix aphylla), an evergreen tree used for shade and as a windbreak in the southwestern U.S. and México, and occasionally feed on native Frankenia spp. plants. The ability of tamarisk beetles to establish on these potential field hosts was investigated in the field. In …

Efficacy And Safety Of Catnip (Nepeta Cataria) As A Novel Filth Fly Repellent, J. J. Zhu, X.-P. Zeng, D. Berkebile, H.-J. Du, Y. Tong, K. Qian

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Catnip (Nepeta cataria) is known for its pseudo-narcotic effects on cats. Recently, it has been reported as an effective mosquito repellent against several Aedes and Culex species, both topically and spatially. Our laboratory bioassays showed that catnip essential oil (at a dosage of 20 mg) resulted in average repellency rates of 96% against stable flies, Stomoxys calcitrans (L.) and 79% against houseflies, Musca domestica (L.), respectively. This finding suggested that the application of repellent could be used as part of filth fly management. Further evaluations of catnip oil toxicity were conducted to provide a broad-spectrum safety profile of …

Physiological And Environmental Regulation Of Interannual Variability In Co2 Exchange On Rangelands In The Western United States, H. Wayne Polley, William Emmerich, James A. Bradford, Phillip L. Sims, Douglas H. Johnson, Nicanor Z. Saliendra, Tony Svejcar, Raymond Angell, Albert B. Frank, Rebecca L. Phillips, Keirith A. Snyder, Jack A. Morgan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

For most ecosystems, net ecosystem exchange of CO₂ (NEE) varies within and among years in response to environmental change.We analyzed measurements of CO₂ exchange from eight native rangeland ecosystems in the western United States (58 site-years of data) in order to determine the contributions of photosynthetic and respiratory (physiological) components of CO₂ exchange to environmentally caused variation in NEE. Rangelands included Great Plains grasslands, desert shrubland, desert grasslands, and sagebrush steppe.

Pollen Contamination Of Boll Weevil Traps, Gretchen D. Jones, Shoil M. Greenberg

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The boll weevil, Anthonomus grandis Boheman, has been the most devastating insect pest of cotton, Gossypium hirsutum L., in the southern United States of America (USA). Although thought to feed only on cotton, the list of non-cotton alternative food sources increases yearly. Many of these taxa are thought to be contaminates and not food sources. The purpose of this research was to examine the possibility that weevils become contaminated with pollen while sitting in the trap. Between January and April, boll weevil traps were placed near Brownsville and Weslaco (a substitute location) and in Santa Ana Wildlife Refuge, Texas. Pollen …

Diet Ph, And Viscosity Affect Development And Survival Of Screwworm Larvae (Diptera: Calliphoridae), M. F. Chaudhury, Steven R. Skoda

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The effects of dietary pH and viscosity on larval development of the New World screwworm, Cochliomyia hominivorax (Coquerel) (Diptera: Calliphoridae), were studied in the laboratory using a gel-based and a cellulose fiber-based media. The mean initial pH of the standard gelled diet was lower (6.5 ± 0.3) than that of the standard cellulose fiber-based diet (6.8 ± 0.6). As larval development progressed, these values decreased to below 6.0 possibly due to the accumulation of acidic metabolic waste. Diets formulated with higher initial pH (7.5) produced a slightly larger and greater number of pupae compared with those for untreated standard diets. …

Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren

Department of Agronomy and Horticulture: Faculty Publications

Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …

Bulked Segregant Analysis Using The Goldengate Assay To Locate The Rpp3 Locus That Confers Resistance To Soybean Rust In Soybean, D. L. Hyten, James R. Smith, Reid D. Frederick, Mark L. Tucker, Qijian Song, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Few resistance loci to soybean rust (SBR), caused by Phakopsora pachyrhizi Syd., have been genetically mapped and linked to molecular markers that can be used for marker assisted selection. New technologies are available for single nucleotide polymorphism (SNP) genotyping that can be used to rapidly map traits controlled by single loci such as resistance to SBR. Our objective was to demonstrate that the highthroughput SNP genotyping method known as the GoldenGate assay can be used to perform bulked segregant analysis (BSA) to fi nd candidate regions to facilitate effi cient mapping of a dominant resistant locus to SBR designated Rpp3 …

Mapping And Confirmation Of A New Allele At Rpp1 From Soybean Pi 594538a Conferring Rb Lesion–Type Resistance To Soybean Rust, Nanda Chakraborty, Joe Curley, Reid D. Frederick, D. L. Hyten, Randall L. Nelson, Glen L. Hartman, Brian W. Diers

Department of Agronomy and Horticulture: Faculty Publications

Soybean rust, caused by Phakopsora pachyrhizi (H. Sydow & Sydow), is a destructive soybean [Glycine max (L.) Merr.] disease and identification of new resistance genes is essential for effective rust management. Our research objectives were to map and confirm the location of resistance gene(s) in PI 594538A using a population of 98 F_3:4 lines from across between PI 594538A (reddish-brown [RB] lesions) and the susceptible cultivar Loda (tan [TAN] lesions). The lines were inoculated with the P. pachyrhizi isolate ZM01-1 from Zimbabwe. The RB resistance in PI 594538A mapped on linkage group G as a single dominant gene. …

Agroecology As A Science, A Movement And A Practice: A Review, A. Wezel, S. Bellon, T. Doré, Charles A. Francis, D. Vallod, C. David

Department of Agronomy and Horticulture: Faculty Publications

Agroecology involves various approaches to solve actual challenges of agricultural production. Though agroecology initially dealt primarily with crop production and protection aspects, in recent decades new dimensions such as environmental, social, economic, ethical and development issues are becoming relevant. Today, the term ‘agroecology’ means either a scientific discipline, agricultural practice, or political or social movement. Here we study the different meanings of agroecology. For that we analyse the historical development of agroecology. We present examples from USA, Brazil, Germany, and France. We study and discuss the evolution of different meanings agroecology. The use of the term agroecology can be traced …

Detection And Validation Of Single Feature Polymorphisms Using Rna Expression Data From A Rice Genome Array, Sung-Hyun Kim, Prasanna R. Bhat, Xinping Cui, Harkamal Walia, Jin Xu, Steve Wanamaker, Abdelbagi M. Ismail, Clyde Wilson, Timothy J. Close

Department of Agronomy and Horticulture: Faculty Publications

Background: A large number of genetic variations have been identified in rice. Such variations must in many cases control phenotypic differences in abiotic stress tolerance and other traits. A single feature polymorphism (SFP) is an oligonucleotide array-based polymorphism which can be used for identification of SNPs or insertion/deletions (INDELs) for high throughput genotyping and high density mapping. Here we applied SFP markers to a lingering question about the source of salt tolerance in a particular rice recombinant inbred line (RIL) derived from a salt tolerant and salt sensitive parent. Results: Expression data obtained by hybridizing RNA to an oligonucleotide array …

Antibiotic Use In Animal Production: Environmental Concerns, Teshome H. Regassa, Richard K. Koelsch, Charles S. Wortmann, Richard F. Randle, Akwasi A. Abunyewa

Department of Agronomy and Horticulture: Faculty Publications

Introduction

Antibiotic1 use in animal production has led to improved feed use efficiency and increased growth rates. In turn, these resulted in reduced food production costs and reduced excrement of manure nutrients which may cause pollution problems.

On the other hand, antibiotic use leads to antibiotic resistance and a possible reduction in effectiveness of treatment options for both animals and humans. This publication addresses these issues.

Disease-causing microorganisms2, including bacteria,are the most diverse and numerous organisms on earth. Diverse in their habitat, environmental adaptation, and mechanisms of reproduction, they have short generations with high multiplication rates. Such characteristics help develop …

Determination By Hplc Fluorescence Analysis Of The Natural Enantiomers Of Sex Pheromones In The New World Screwworm Fly, Cochliomyia Hominivorax, K. Akasaka, D. A. Carlson, T. Ohtaka, H. Ohrui, K. Mori, D. R. Berkebile

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Bioassays of six racemic synthesized candidate sex pheromone compounds against male New World screwworm Cochliomyia hominivorax (Coquerel) flies showed that the most potent bioactivity was found with 6-acetoxy-19-methylnonacosane and 7-acetoxy-15-methylnonacosane compared with four other isomeric acetoxy nonacosanes and a larger aliphatic ketone. As all these methyl-branched compounds have two asymmetric carbons and four possible enantiomers, characterization of the natural enantiomers was essential. All four enantiomers for the two most bioactive isomers of the natural sex pheromone were synthesized for bioassay. Hydrolysis and derivatization of these enantiomers with different fluorescent reagents was followed by columnswitched high-performance liquid chromatography. The use of …

Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Fuels Production, John L. Kovar, Douglas Karlen

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The short- and long-term effects on soil nutrient cycling, physical properties, and biological activity of striving for higher grain yields and removing crop residues for bio-fuels production must be understood to provide more quantitative crop and soil management guidelines. This study focuses on potassium (K) and sulfur (S) requirements of corn (Zea mays L.) grown for bioenergy feedstock production. Our objectives for 2008 were to: i) evaluate the performance of several S fertilizers, including liquid ammonium thiosulfate (12-0-0-26S), as S sources for corn grown in Iowa, and ii) establish a comprehensive tillage, nutrient management, crop residue removal, and cover …

Genotypic Variability In Mineral Composition Of Switchgrass, H. M. El-Nashaar, G. Banowetz, S.M. Griffith, M. D. Casler, Kenneth P. Vogel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Switchgrass (Panicum virgatum L.) is a warm season perennial grass with great potential as an energy crop in the USA. It is widely adapted to many regions of the country, produces large amounts of biomass, serves as a useful forage grass, and provides ecosystem services that benefit soil and water quality and wildlife. Biological and thermochemical technologies are being developed to convert herbaceous biomass, including switchgrass, to energy. The objective of this research was to determine the effect of genotype and production environment on the concentration of minerals that affect the suitability of switchgrass for thermochemical conversion and to …

Comparison Of Passive And Active Canopy Sensors For The Estimation Of Vine Biomass Production, Stamatis Stamatiadis, Dimitris Taskos, Eleftheria Tsadila, Calliopi Christofides, Christos Tsadilas, James S. Schepers

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Recent advances in optical designs and electronic circuits have allowed the transition from passive to active proximal sensors. Instead of relying on the reflectance of natural sunlight, the active sensors measure the reflectance of modulated light from the crop and so they can operate under all lighting conditions. This study compared the potential of active and passive canopy sensors for predicting biomass production in 25–32 randomly selected positions of a Merlot vineyard. Both sensors provided estimates of the normalized difference vegetation index (NDVI) from a nadir view of the canopy at veraison that were good predictors of pruning weight. Although …

Comparative Metabolism Of Benzo(A)Pyrene By Ovarian Microsomes Of Various Species, Deacqunita L. Harris, Ashley C. Huderson, Mohammad S. Niaz, J. Joe Ford, Anthony E. Archibong, Aramandla Ramesh

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Knowledge of the ability of the female reproductive system to metabolize polycyclic aromatic hydrocarbons (PAHs) is critical to the diagnosis and management of female infertility and for risk assessment purposes. The PAHs are a family of widespread pollutants that are released into the environment from automobile exhausts, cigarette smoke, burning of refuse, industrial emissions, and hazardous waste sites. In exposed animals, PAHs become activated to reactive metabolites that interfere with target organ function and as a consequence cause toxicity. The extent of susceptibility to PAH exposure may depend on the ability of animals to metabolize these chemicals. The present study …

Tests Of Concepts For Streamflow Sampler Design, John A. Replogle

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Total-load sampling has been a perpetual problem in sediment monitoring. Usually a combination of bed-load sampling devices, suspended load suction samplers, and some kind of flume, for total flow rate, is used. Total-load, sediment-sampler-design concepts that can perform all three of these functions are proposed. The resulting designs would require installation at sites that can provide a step-overfall height about equal to the maximum channel flow depth. The concepts are simple, but appear to have been overlooked or ignored for the past many decades, and are based on a moving conveyor belt that is long and wide, with many slots, …

Protocol For Indicator Scoring In The Soil Management Assessment Framework (Smaf), Brian J. Wienhold, D. L. Karlen, S.S. Andrews, D. E. Stott

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Assessment tools are needed to evaluate agronomic management effects on critical soil functions such as carbon sequestration, nutrient cycling and water partitioning. These tools need to be flexible in terms of selection of soil functions to be assessed and indicators to be measured to ensure that assessments are appropriate for the management goals. The soil management assessment framework (SMAF) is being developed to meet this need. The SMAF uses soil physical, chemical and biological indicator data to assess management effects on soil function using a three-step process for (1) indicator selection, (2) indicator interpretation and (3) integration into an index. …

Morphology Of The Turkey Vagina With And Without An Egg Mass In The Uterus, M. R. Bakst, V. Akuffo

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In this study we examined the gross anatomy of the uterus and vagina in turkeys in egg production. With no uterine egg mass, removal of the tunica serosa that enclosed the uterus revealed deep periodic in-folding of the muscularis transversely circumscribing the sac-like segment. When the connective tissue embracing the neutral buffered formalin fixed vagina was completely teased free, the exposed tubular segment was shaped as a counter-clockwise spiral or as a series of angular, random bends. The uterovaginal junction was flush with the uterine mucosa or projected slightly into the uterine lumen. With a uterine egg mass, the deep …

Red Angus Osteopetrosis Sequence Information, Tim Smith

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The recessive genetic defect of osteopetrosis (marble bone disease) in Red Angus cattle has been defined by a mutation in the bovine SLC4A2 gene located on Bos Taurus chromosome 4. The mutation was discovered in a joint effort by the Red Angus Association of America (RAAA), University of Illinois, University of Nebraska-Lincoln, University of Wyoming, and the Agricultural Research Service of the United States Department of Agriculture (USDA-ARS). The information is available for public use without restriction, taking into account the disclaimers and caveats described below.

The causative mutation is a deletion of ~2721 bp of the SLC4A2 gene. This …

Upic: Perl Scripts To Determine The Number Of Ssr Markers To Run, R. S. Arias, Linda L. Ballard, Brian E. Scheffler

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

We introduce here the concept of Unique Pattern Informative Combinations (UPIC), a decision tool for the cost-effective design of DNA fingerprinting/genotyping experiments using simple-sequence/tandem repeat (SSR/STR) markers. After the first screening of SSR-markers tested on a subset of DNA samples, the user can apply UPIC to find marker combinations that maximize the genetic information obtained by a minimum or desirable number of markers. This allows a cost-effective planning of future experiments. We have developed Perl scripts to calculate all possible subset combinations of SSR markers, and determine based on unique patterns or alleles, which combinations can discriminate among all DNA …

Response Of Adult Mosquitoes To Light-Emitting Diodes Placed In Resting Boxes And In The Field, Michael T. Bentley, Phillip E. Kaufman, Daniel L. Kline, Jerome A. Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The response of adult mosquitoes to 4 light-emitting diode (LED) wavelengths was evaluated using diode-equipped sticky cards (DESCs) and diode-equipped resting boxes at 2 sites in north central Florida. Wavelengths evaluated were blue (470 nm), green (502 nm), red (660 nm), and infrared (IR) (860 nm). When trapping with DESCs, 15 mosquito species from 7 genera (Aedes, Anopheles, Coquillettidia, Culex, Mansonia, Psorophora, and Uranotaenia) were captured. Overall, approximately 43.8% of all mosquitoes were trapped on DESCs fitted with green LEDs. Significantly more females of Aedes infirmatus, Aedes vexans, and Culex nigripalpus were captured on DESCs fitted with blue …

Efficiency And Establishment Of Three Introduced Parasitoids Of The Mealybug Paracoccus Marginatus (Hemiptera: Pseudococcidae), Kaushalya G. Amarasekare, Catharine M. Mannion, Nancy D. Epsky

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Three introduced parasitoids Acerophagus papayae, Anagyrus loecki, and Pseudleptomastix mexicana of the mealybug Paracoccus marginatus have been released in Miami-Dade and Broward counties (Florida) in 2003. Efficiency and establishment of these previously introduced parasitoids to control P. marginatus were measured in 2005 and 2006, at three locations in Homestead (Miami-Dade). Mealybug populations were initially established on three branches (per plant) of 10 hibiscus plants inside closed-sleeve cages. The three treatments, closed, open, and no-cage environments were applied to the three established mealybug populations on each plant. The number of mealybugs and natural enemies was monitored in all treatments. …

Host Range Of Tetramesa Romana Walker (Hymenoptera: Eurytomidae), A Potential Biological Control Of Giant Reed, Arundo Donax L. In North America, John A. Goolsby, Patrick Moran

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The eurytomid wasp, Tetramesa romana Walker was evaluated as a potential biological control agent of the invasive reed grass, Arundo donax in North America. No-choice tests and timed behavioral studies were used to determine the fundamental host range of two genotypes of the wasp collected from Granada, Spain and Perpignan, France. Thirty-five species, including two genotypes of A. donax and seven ecotypes of Phragmites australis, along with closely related grasses, economic grasses and habitat associates were tested. Complete development of both T. romana genotypes was restricted to A. donax and Arundo formosana. The mean number of offspring produced …

Flight Phenology Of Male Cactoblastis Cactorum (Lepidoptera: Pyralidae) At Different Latitudes In The Southeastern United States, Stephen D. Hight, James E. Carpenter

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Long term trapping studies of the invasive moth Cactoblastis cactorum (Berg) were conducted at various latitudes from Puerto Rico to South Carolina. Three flight periods per year were identified at the 5 temperate sites studied, which covered the majority of the infested range on mainland United States. In general, the 3 flight periods across a latitudinal gradient from south Florida to central, coastal South Carolina were a spring flight during Feb-May, a summer flight during Jun-Aug, and a fall flight during Sep-Nov. At any 1 site, each flight period lasted about 2 months. In the tropical areas of the Florida …

Field Assessment Of Host Plant Specificity And Potential Effectiveness Of A Prospective Biological Control Agent, Aceria Salsolae, Of Russian Thistle, Salsola Tragus, Lincoln Smith, Massimo Cristofaro, Enrico De Lillo, Rosita Monfreda, Alessandra Paolini

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The eriophyid mite, Aceria salsolae de Lillo and Sobhian, is being evaluated as a prospective classical biological control agent of invasive alien tumbleweeds, including Salsola tragus, S. collina, S. paulsenii and S. australis, in North America. Previous laboratory experiments to determine the host specificity of the mite indicated that it could sometimes persist and multiply on some nontarget plants, including Bassia hyssopifolia and B. scoparia. These are both European plants whose geographic range overlaps that of the mite, but the mite has never been observed on them in the field. A field experiment was conducted in …

Differential Induction Of Redox Sensitive Extracellular Phenolic Amides In Potato, C. Jacyn Baker, Bruce D. Whitaker, Norton M. Mock, Clifford P. Rice, Daniel P. Roberts, Kenneth L. Deahl, Peter P. Ueng, Andrey A. Aver’Yanov

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This study focuses on the differential induction of extracellular phenolic amides that accumulate in potato cell suspensions during the first few hours of the interaction between these plant cells and either bacterial pathogens or pathogen-related elicitors. Using suspension cells of Solanum tuberosum we identified 4 hydroxycinnamic acid amides that accumulate in the extracellular environment. Treatment of the suspension cells with pathovars of the plant pathogens Pseudomonas syringae or Ralstonia solanacearum or with pathogen-related elicitors changed the composition of the extracellular phenolic amides within hours and the composition differed for each treatment. Some of the phenolic amides were sensitive to oxidative …

Where To Sample? Ecological Implications Of Sampling Strata In Determining Abundance And Impact Of Natural Enemies Of The Coffee Berry Borer, Hypothenemus Hampei, Juliana Jaramillo, Adenirin Chabi-Olaye, Christian Borgemeister, Charles Kamonjo, Hans-Michael Poehling, Fernando E. Vega

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Several parasitoids of African origin have been introduced to coffee producing areas of the Americas and Asia as biological control agents of the coffee berry borer (CBB) Hypothenemus hampei (Coleoptera: Curculionidae). These parasitoids have become established in the field but their effect on the CBB has been limited. A two-year field study in Western Kenya has found Prorops nasuta (Hymenoptera: Bethylidae) to be the predominant parasitoid emerging from CBB-infested coffee berries collected on coffee trees or from the ground. P. nasuta comprises more than 75% of the total natural enemies collected. The density of P. nasuta was 90% higher in …

Root Responses Along A Subambient To Elevated Co2 Gradient In A C3–C4 Grassland, Laurel J. Anderson, Justin D. Derners, H. Wayne Polley, Wendy S. Gordon, David M. Eissenstat, Robert B. Jackson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Atmospheric CO₂ (C_a) concentration has increased significantly during the last 20 000 years, and is projected to double this century. Despite the importance of belowground processes in the global carbon cycle, community-level and single species root responses to rising C_a are not well understood. We measured net community root biomass over 3 years using ingrowth cores in a natural C₃–C₄ grassland exposed to a gradient of C_a from preglacial to future levels (230–550 µmol mol^-1).

Nitrogen And Phosphorus Accumulation In Pasture Soil From Repeated Poultry Litter Application, Zhongqi He, C. Wayne Honeycutt, Irenus A. Tazisong, Zachary N. Senwo, Donglin Zhang

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Poultry litter (PL) is a traditionally inexpensive and effective fertilizer to improve soil quality and agricultural productivity. However, over application to soil has raised concern because excess nutrients in runoff could accelerate the eutrophication of fresh water. In this work, we determined the contents of total phosphorus (P), Mehlich 3 extracted P, total nitrogen (N), ammonium (NH4)-N, and nitrate (NO₃)-N, in pasture soils receiving annual poultry litter applications of 0, 2.27, 2.27, 3.63, and 1.36 Mg/ha/ yr, respectively, for 0, 5, 10, 15, and 20 years. Samples were collected from three soil depths (0–20, 20–40, and 40–60 cm) …