Agronomy and Crop Sciences Commons^™

Defining The Potassium Nutritional Requirements And Distribution Among Plant Parts Of Representative Soybean Cultivars From Different Maturity Groups, Md. Rasel Parvej

Graduate Theses and Dissertations

The potassium (K) requirement of soybean [Glycine max (L.) Merr.] was investigated to determine whether cultivar sensitivity to K deficiency was affected by growth habit (determinate or indeterminate) and how cultivars from each growth habit accumulate and distribute K among plant structures. We also diagnosed K deficiency across reproductive growth stages (R2-6) using trifoliolate leaf- and petiole-K concentrations and at harvest (R8) using seed-K concentration. Soybean responded similarly to K deficiency in terms of yield, selected yield components, and seed-K concentration, regardless of growth habit. The yield loss from K deficiency was greatest on the middle to upper nodes of …

The Effects Of Foliar Nutrient Applications On Split, Yield, And Internal Fruit Quality Of 'Wonderful' Pomegranate (Punica Granatum L.), John Matthew Chater

Master's Theses

Fruit split is the most important physiological disorder in pomegranate production, causing devastating crop losses worldwide. Foliar nutrient applications have been used experimentally to mitigate pomegranate fruit split but none have been conducted using the industry standard cultivar, Wonderful, and little is known about the effects of foliar nutrient applications on pomegranate. Additionally, investigations into putative health benefits of pomegranate fruit have increased interest in its production but limited evidence exists regarding effects of agricultural practices such as foliar fertilizer applications on internal fruit quality. ‘Wonderful’ pomegranate trees at 2 commercial orchards were treated with foliar applications of ZnSO_{4 …}

Arkansas Soybean Performance Tests 2015, R. D. Bond, J. A. Still, D. G. Dombek

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.

Validation Of Soil-Test-Based Phosphorus And Potassium Fertilizer Recommendations For Rice And Soybean, Matthew Scott Fryer

Graduate Theses and Dissertations

The science of soil-testing for nutrient management and fertilizer recommendations is widely accepted among scientists and agronomists. Although this science is unsurpassed in predicting soil nutrient availability, soil-test interpretations are seldom validated. Major research objectives for irrigated soybean [Glycine max (L.) Merr.] and direct-seeded, delayed-flood rice (Oryza sativa L.) were to: i) validate the accuracy of Mehlich-3 soil-test P (STP) and K (STK) interpretations and ii) published critical tissue-P and -K interpretations in predicting the yield response to fertilizer at different significance levels (p≤0.05 to 0.25), iii) examine how seed nutrient concentrations are influenced by fertilization and crop response to …

Soybean Planting And Risk-Return Tradeoffs In The Mid-Southern United States, Weston Weeks

Graduate Theses and Dissertations

This thesis is comprised of two studies on the effects of soybean (Glycine max (L.) Merr.) planting date (PD) and maturity group (MG) selection on producer expected returns. Having to replant soybean after early-season planting because of poor stand establishment is costly for producers. Replanting costs have increased in the last ten years as seed and other input costs for soybean have increased. Using five years of field trial results from two locations in Arkansas, the yield response to early and late season plant population density has been estimated to determine yield and future revenue potential for the purpose of …

Distribution Of Herbicide-Resistant Shattercane And Johnsongrass Populations In Sorghum Production Areas Of Nebraska And Northern Kansas, Rodrigo Werle, Amit J. Jhala, Melinda K. Yerka, J. Anita Dille, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Overreliance on acetolactate synthase (ALS)-inhibiting herbicides for weed control during the 1990s resulted in selection of ALS-resistant shattercane [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud.) de Wet ex Davidse] biotypes in Nebraska. The objective of this study was to assess the baseline presence of ALS-resistance in 190 shattercane and 59 johnsongrass [Sorghum halepense (L.) Pers.] populations collected across northern Kansas, northwestern Missouri, and southern Nebraska in 2013. In 2014, a preliminary field experiment was conducted to evaluate the presence of herbicide resistance in the aforementioned populations. Treatments consisted of four herbicides (clethodim {2-[1-[[(E)-3-chloroprop-2-enoxy]amino] propylidene]-5-(2-ethylsulfanylpropyl)cyclohexane-1,3-dione}, glyphosate [N-(phosphonomethyl) …

Canola: A Modern Crop For A Modern Era, Kenneth J. Roché

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska-Lincoln Doctor of Plant Health program is a professional doctorate program with a comprehensive approach to plants and agriculture. The program emphasizes a broad interdisciplinary education across all plant-related disciplines, practical learning, research, and experience through internships. For my final required internship, I worked as a senior agricultural research intern with Research Designed for Agriculture (RD4AG) in Montana. RD4AG is a contract research organization based in Yuma, AZ with over thirty-years of experience. During my three month internship at RD4AG in Montana, a large portion of my responsibilities centered on managing regulated canola trials that were undertaken …

Soybean Irrigation Initiation Timing Using Evapotranspiration And Soil Moisture Sensor Cues, Justin Chlapecka

Student Theses and Dissertations

Expanded use of irrigation management tools is needed to improve water use efficiency in eastern Arkansas soybean (Glycine max) production. Irrigation initiation timing was studied on a furrow irrigated, sandy loam commercial field in Mississippi County. A major objective was to develop, validate, and expand use of irrigation timing cues, incorporating local weather station data, atmometers, and soil moisture measurements. Four timing treatments were evaluated: early, recommended, late, and rainfed, and the crop and pest response to each. With above average rainfall in 2014 and 2015, results showed little variation of soybean yield. Yield monitor data indicated penalties only within …

Genetic Control Of Morphometric Diversity In The Maize Shoot Apical Meristem, Samuel Leiboff, Xianran Li, Heng-Cheng Hu, Natalie Todt, Jinliang Yang, Xiao Li, Xiaoqing Yu, Gary J. Muehlbauer, Marja C.P. Timmermans, Jianming Yu, Patrick S. Schnable, Michael J. Scanlon

Department of Agronomy and Horticulture: Faculty Publications

The maize shoot apical meristem (SAM) comprises a small pool of stem cells that generate all above-ground organs. Although mutational studies have identified genetic networks regulating SAM function, little is known about SAM morphological variation in natural populations. Here we report the use of high-throughput image processing to capture rich SAM size variation within a diverse maize inbred panel. We demonstrate correlations between seedling SAM size and agronomically important adult traits such as flowering time, stem size and leaf node number. Combining SAM phenotypes with 1.2 million single nucleotide polymorphisms (SNPs) via genome-wide association study reveals unexpected SAM morphology candidate …

Residue Harvest Effects On Irrigated, No-Till Corn Yield And Nitrogen Response, Charles S. Wortmann, Charles A. Shapiro, Marty R. Schmer

Department of Agronomy and Horticulture: Faculty Publications

Crop residue harvest occurs on about 40% of Nebraska’s 3,700,000 ha of corn (Zea mays L.) land, primarily for feeding of beef cattle. Immobilization of applied N is expected to be less with residue harvest due to reduced microbial activity for digestion of high C/N ratio organic material. Residue reduction may affect subsequent crop yield and response to applied N. Field research was conducted at three locations over 2 yr in eastern Nebraska for irrigated, no-till corn following corn to determine residue harvest effects on yield and the economically optimal nitrogen rate (EONR). Study sites had deep silt loam …

Evidence Of Field-Evolved Resistance To Bifenthrin In Western Corn Rootworm (Diabrotica Virgifera Virgifera Leconte) Populations In Western Nebraska And Kansas, Adriano E. Pereira, Haichuan Wang, Sarah N. Zukoff, Lance Meinke, B. Wade French, Blair Siegfried

Department of Entomology: Faculty Publications

Pyrethroid insecticides have been used to control larvae or adults of the western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, a key pest of field corn in the United States. In response to reports of reduced efficacy of pyrethroids in WCR management programs in southwestern areas of Nebraska and Kansas the present research was designed to establish a baseline of susceptibility to the pyrethroid insecticide, bifenthrin, using susceptible laboratory populations and to compare this baseline with susceptibility of field populations. Concentration-response bioassays were performed to estimate the baseline susceptibility. From the baseline data, a diagnostic concentration (LC99) was determined and …

Herbicides Applied At Or Shortly After Seeding Are Effective For Weed Control In Seedling Buffalograss, Luqi Li, Matthew D. Sousek, Zachary Reicher

Department of Agronomy and Horticulture: Faculty Publications

Herbicides applied shortly after seeding of buffalograss [Buchloe dactyloides (Nutt.) Engelm.] can help reduce weed pressure and maximize establishment of buffalograss. This study evaluated 12 relatively recently developed herbicides for turf safety and weed control when applied at seeding or 0 or 2 weeks after emergence (WAE) of ‘Bowie’ or ‘Sundancer’ buffalograss. Primary weed species on the site were common purslane (Portulaca oleracea L.), redroot pigweed (Amaranthus retroflexus L.), and/or yellow foxtail [Setaria lutescens (Weigel ex Stuntz) F.T. Hubb.]. Regardless of cultivar, untreated checks had53% weed cover by 6 WAE, whereas most of the herbicide treatments resulted …

Synfind: Compiling Syntenic Regions Across Any Set Of Genomes On Demand, Haibao Tang, Matthew D. Bomhoff, Evan Briones, Liangsheng Zhang, James C. Schnable, Eric Lyons

Department of Agronomy and Horticulture: Faculty Publications

The identification of conserved syntenic regions enables discovery of predicted locations for orthologous and homeologous genes, evenwhennosuchgeneispresent.Thiscapabilitymeansthatsynteny-basedmethodsarefarmoreeffectivethansequencesimilaritybased methods in identifying true-negatives, a necessity forstudying gene loss and gene transposition. However, the identification of syntenicregionsrequirescomplexanalyseswhichmustberepeatedforpairwisecomparisonsbetweenanytwospecies.Therefore,as the number of published genomes increases, there is a growing demand for scalable, simple-to-use applications to perform comparative genomic analyses that cater to both gene family studies and genome-scale studies. We implemented SynFind, a web-based tool that addresses this need. Given one query genome, SynFind is capable of identifying conserved syntenic regions in any set of targetgenomes.SynFindiscapableofreportingper-geneinformation,usefulforresearchersstudyingspecificgenefamilies,aswellas genome-wide data sets of syntenic gene and predicted gene …

A Population Structure And Genome-Wide Association Analysis On The Usda Soybean Germplasm Collection, Nonoy Bandillo, Diego Jarquin, Qijian Song, Randall L. Nelson, Perry Cregan, James Specht, Aaron Lorenz

Department of Agronomy and Horticulture: Faculty Publications

Population structure analyses and genome-wide association studies (GWAS) conducted on crop germplasm collections provide valuable information on the frequency and distribution of alleles governing economically important traits. The value of these analyses is substantially enhanced when the accession numbers can be increased from ~1,000 to ~10,000 or more. In this research, we conducted the first comprehensive analysis of population structure on the collection of 14,000 soybean accessions [Glycine max (L.) Merr. and G. soja Siebold & Zucc.] using a 50KSNP chip. Accessions originating from Japan were relatively homogenous and distinct from the Korean accessions. As a whole, both Japanese and …

Arkansas Corn And Grain Sorghum Performance Tests 2015, R. D. Bond, J. A. Still, D. G. Dombek

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state, and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers.

Enhancing The Effectiveness Of Biological Control Programs Of Invasive Species By Utilizing An Integrated Pest Management Approach, Invasive Species Advisory Committee

National Invasive Species Council

Conclusion

Biological control has been shown on many occasions to be the most cost-effective invasive species management tool available. However, integrating biological control projects with the full breadth of other integrated pest management (IPM) tools, expanding post-re- lease monitoring to maximize efficacy, adaptive management, and incorporating new and innovative ecological, and genetic technologies may provide private and public land managers greater opportunities for long-term success in suppression of established invasive species.

Pengaruh Pemberian Zat Retardan Terhadap Pertumbuhan Dan Hasil Ubi Pada Dua Kultivar Kentang (Solanum Tuberosum L.) Di Dataran Medium, Sumadi, Erni Suminar, Murgayanti, Anne Nuraini

Jurnal Kultivasi

Tujuan dari kegiatan penelitian ini adalah untuk mendapatkan informasi mengenai kulti-var kentang dan jenis serta konsentrasi zat retardan yang dapat mendukung pertumbuhan dan perkembangan serta kuantitas dan kualitas hasil ubi bibit kentang di dataran medium. Metode penelitian yang digunakan adalah Rancangan Petak terpisah. Perlakuan terdiri dari petak utama yaitu kultivar yaitu kultivar Nadia dan Granola, dan anak petak yaitu jenis dan konsentrasi zat retardan dengan penggunaan paklobutrazol ( 0; 40; 120 mg L-1 ) atau coumarin (45; 90; 135 mg L-1). Hasil percobaan menun-jukkan bahwa jenis kultivar dan zat retardan berpengaruh terhadap pertumbuhan dan per-kembangan bibit kentang. Terjadi interaksi pada …

Pengaruh Keberadaan Gulma (Ageratum Conyzoides Dan Boreria Alata) Terhadap Pertumbuhan Dan Hasil Tiga Ukuran Varietas Kedelai (Glycine Max L. Merr) Pada Percobaan Pot Bertingkat, Abdul Karim Kilkoda, Tati Nurmala, Dedi Widayat

Jurnal Kultivasi

Percobaan dilaksanakan di rumah kaca Fakultas Pertanian Universitas Padjadjaran, Jati-nangor, Kabupaten Sumedang, Jawa Barat. Tujuan dari penelitian ini adalah untuk menguji eksudat akar yang terdapat pada gulma Ageratum conyzoides dan Borreria alata terhadap pertumbuhan dan hasil tanaman kedelai. Percobaan dilakukan mulai dari bulan Oktober 2014 sampai dengan bulan Desember 2014 dengan menggunakan rancangan acak kelompok pola faktorial. Faktor perlakuan pertama adalah jenis gulma terdiri dari 3 taraf antara lain gulma A. Conyzoides, gulma B. alata dan tanpa gulma (kontrol). Perlakuan kedua adalah ukuran benih varietas kedelai yang terdiri dari 3 taraf. Total kombinasi perlakuan adalah 9 kombinasi perlakuan, dengan 3 …

Pengaruh Dosis Herbisida Glifosat Terhadap Gulma, Pertumbuhan, Dan Hasil Tiga Kultivar Kedelai (Glycine Max (L.) Pada Sistem Tanpa Olah Tanah (Tot), Dedi Widayat, R. Ganilda Yustisiyanika

Jurnal Kultivasi

Penelitian ini bertujuan untuk mengetahui pengaruh interaksi antara dosis herbisida Glifosat dan kultivar kedelai terhadap gulma, pertum-buhan, dan hasil tanaman kedelai. Percobaan dilakukan di Kebun Percobaan Saung Meeting Ciparanje Universitas Padjadjaran Jatinangor, Kabupaten Sumedang. Rancangan percobaan yang digunakan adalah rancangan acak kelompok pola faktorial yang terdiri dari dua faktor dan diulang 3 kali. Faktor yang pertama adalah kultivar kedelai yang tediri dari tiga yaitu kultivar Tidar, Burangrang, dan Slamet. Faktor yang kedua dosis herbisida glifosat yang terdiri dari 3 taraf yaitu 1,5l/ha, 3l/ha, dan 4,5l/ha. Kombinasi perlakuan kultivar dan dosis herbisida glifosat tidak memberikan pengaruh interaksi terhadap bobot kering gulma …

Pengaruh Dosis Pupuk Fosfor Dan Pupuk Organik Cair Terhadap Pertumbuhan Dan Hasil Kacang Hijau (Vigna Radiata L.) Pada Ultisol Jatinangor, Agus Wahyudin, Tati Nurmala, R. D. Rahmawati

Jurnal Kultivasi

Percobaan ini bertujuan untuk mengetahui pengaruh dosis pupuk fosfor dan pupuk organik cair terhadap pertumbuhan dan hasil tanaman kacang hijau (Vigna radiata L.). Percobaan dilaksanakan di kebun percobaan Fakultas Pertanian Universitas Padjadjaran, Jatinangor, Jawa Barat. Rancangan percobaan yang digunakan dalam penelitian ini adalah Rancangan Acak Kelompok (RAK) dengan sembilan perlakuan dan diulang tiga kali yaitu 50 kg ha-1 pupuk fosfor + O L ha-1 pupuk organik cair, 50 kg ha-1 pupuk fosfor + 4 L ha-1 pupuk organik cair, 50 kg ha-1 pupuk fosfor + 8 L ha-1 pupuk organik cair, 75 kg ha-1 pupuk fosfor + O L ha-1 …