Agricultural Science Commons^™

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 …

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.

Effects Of Agroforestry On Pest, Disease And Weed Control: A Meta-Analysis, Lorena Pumariño, Gudeta Weldesemayat Sileshi, Sofia Gripenberg, Riikka Kaartinen, Edmundo Barrios, Mary Nyawira Muchane, Charles Midega, Mattias Jonsson

All Peer-Reviewed Publications

Agroforestry practices may influence pest incidence and abundance both through increased top-down regulation by natural enemies and via bottom-up factors such as moderation of microclimate, soil nutrients and water content. We conducted a meta-analysis of the effects of agroforestry on the abundance of invertebrate pests, weeds, natural enemies and plant damage due to pests and diseases. We also tested whether effects of agroforestry were dependent on crop type (annual or perennial), type of pest association (above or belowground) and weed type (parasitic Striga weeds or non-parasitic weeds).Agroforestry practices resulted in lower abundances of both parasitic and non-parasitic weeds, and in …

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 Sitokinin Dan Paklobutrazol Terhadap Pertumbuhan Dan Hasil Benih Kentang (Solanum Tuberosum L.) G2 Kultivar Granola Dengan Sistem Nutrient Film Technique, M. Ibrahim, Anne Nuraini, Dedi Widayat

Jurnal Kultivasi

Percobaan ini dilakukan untuk mengetahui pengaruh sitokinin dan paklobutrazol terhadap pertumbuhan dan hasil benih kentang (Solanum tuberosum L.) G2 kultivar Granola dengan menggunakan sistem Nutrient Film Technique. Percobaan dilakukan di rumah plastik CV. Alam Pasundan, Cibiru, Bandung dari bulan April sampai dengan Agustus 2014 dengan ketinggian lokasi penelitian ± 700 m dpl. Rancangan perco-baan yang digunakan adalah Rancangan Acak Kelompok dengan enambelas perlakuan dan masing-masing terdiri dari tiga ulangan. Perlakuan yang digunakan adalah: A (kontrol), B (25 ppm sitokinin), C (50 ppm sitokinin), D (75 ppm sitokinin), E (50 ppm paklobutrazol), F (100 ppm paklobutrazol), G (150 ppm paklobutrazol), H …

Skrining Fitokimia Cangkang Dan Kulit Batang Tanaman Jengkol Asal Ciamis Jawa Barat Sebagai Inisiasi Obat Diabetes Mellitus Berbahan Alam, Yudithia Maxiselly, Ade Ismail, Santi Rosniawaty, Intan Ratna Dewi Anjarsari

Jurnal Kultivasi

Pengembangan obat bahan alam semakin meningkat karena mempertimbangkan pola masyarakat yang kini lebih memilih hidup back to nature.Jengkol merupakan salah satu tanaman yang memiliki potensi sebagai obat bahan alam. Kandungan jengkol yang bermanfaat yaitu asam amino, vitamin, mineral, juga zat lain seperti saponin, flavonoid, dan tannin sangat dibutuhkan manusia. Potensi jengkol lainnya adalah mampu menurunkan kadar gula dalam darah sehingga dapat mencegah penyakit Diabetes Mellitus (DM). Bagian jengkol yang diteliti memiliki zat antidiabetes adalah kulit batang, cangkang buah dan bijinya. Penelitian ini bertujuan melihat kandungan fitokimia pada cangkang dan kuit batang jengkol asal Ciamis Jawa Baratyang telah berhasil dikoleksi oleh …

Dampak Perubahan Iklim Pada Produksi Apel Di Batu Malang Impacts Of Climate Change On Production Of Apple In Batu Malang, Ruminta

Jurnal Kultivasi

Perubahan iklim telah menjadi isu penting yang mengakibatkan kenaikan suhu global, perubahan pola curah hujan, kenaikan muka air laut, dan peningkatan frekwensi dan intensitas cuaca ekstrim. Perubahan iklim mempunyai pengaruh signifikan pada bidang pertanian, karena pertanian mempunyai ketergantungan yang kuat terhadap unsur iklim. Terkait dengan hal itu telah dilakukan penelitian dampak perubahan iklim terhadap produksi tanaman apel di wilayah Batu Malang Jawa Timur. Penelitian bertujuan untuk mengetahui dampak perubahan unsur iklim yaitu temperatur dan curah hujan terhadap produksi apel dan mengidentifikasi usaha adaptasi yang harus dilakukan oleh para petani. Hasil penelitian menunjukkan bahwa wilayah Batu Malang telah mengalami perubahan iklim. …

Pertumbuhan Dan Perkembangan Tunas Nilam Var. Lhoukseumawe Dari Jenis Eksplan Dengan Sitokinin Yang Berbeda Secara In Vitro, Erni Suminar, Intan Ratna Dewi Anjarsari, Anne Nuraini, Hapizhah

Jurnal Kultivasi

Tujuan dari penelitian ini adalah untuk mendapatan metode perbanyakan tanaman nilam melalui teknik in vitro dengan meng-gunakan jenis eksplan serta jenis dan konsentrasi sitokinin yang berbeda. Percobaan dilaksanakan di Laboratorium Teknologi Benih Fakultas Pertanian Universitas Padjadjaran dari bulan Maret sampai dengan Juni 2012. Rancangan percobaan menggunakan Rancangan Acak Lengkap pola faktorial yang terdiri dua faktor dan tiga kali ulangan. Faktor pertama adalah tipe eksplan (mata tunas, pucuk, dan daun). Faktor kedua adalah tipe dan konsentrasi sitokinin (0 mg L-1, 0,5 mgL-1 BAP, 1,0 mgL-1 BAP0,5 mgL-1 zeatin, and 1,0 mgL-1 zeatin). Hasil percobaan menunjukkan bahwa eksplan pucuk dengan penggunaan 0.5 …

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 …

Adding Genetically Distant Individuals To Training Populations Reduces Genomic Prediction Accuracy In Barley, Aaron Lorenz, Kevin P. Smith

Department of Agronomy and Horticulture: Faculty Publications

One of the most important factors affecting genomic prediction accuracy appears to be training population (TP) composition. The objective of this study was to evaluate the effect of genomic relationship on genomic prediction accuracy and determine if adding increasingly unrelated individuals to a TP can reduce prediction accuracy. To accomplish this, a population of barley (Hordeum vulgare L.) lines from the University of Minnesota (lines denoted as MN) and North Dakota State University (lines denoted as ND) breeding programs were used for model training. Predictions were validated using two independent sets of progenies derived from MN  MN crosses …

Switchgrass Germplasm Resources, Michael D. Casler, Kenneth P. Vogel, Melanie Harrison

Department of Agronomy and Horticulture: Faculty Publications

Switchgrass (Panicum virgatum L.) is an important native grass and dominant member of the tallgrass prairie ecosystem. It is used for conservation, restoration, livestock feed production, and bioenergy feedstock production. The purpose of this review is to describe the biological and geographical basis for switchgrass germplasm diversity and to provide a resource for scientists and outreach personnel to find switchgrass germplasm to meet their needs. Upland and lowland ecotypes represent the most important polymorphism in switchgrass, with distinct but overlapping geographic distributions. Variation in ploidy exists within both ecotypes, with 2n = 4x = 36 the dominant ploidy …

Community Seed Banks: Origins, Evolution, And Prospects, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

As a survey of contemporary community-level seed banks, this is an excellent compilation and instructive guide. The first section provides an overview of how seed banks originated, their varied goals and activities, several contrasting forms of management, and how they organize and perform to meet these goals. An intriguing claim in the book is that the concept of “seed banks is only some three decades old,” while in fact the practice of saving, preserving, and exchanging seed within a community is probably as old as human communities themselves.

Organized seed banks often serve specific functions: preserving seeds, providing seed access …

Management Options For Water-Repellent Soils In Australian Dryland Agriculture, M. M. Roper, S. L. Davies, P. S. Blackwell, D. J. M. Hall, D. Bakker, R. Jongepier, P. R. Ward

Natural Resources Research Articles

Water-repellent (‘non-wetting’) soils are a major constraint to agricultural production in southern and south-west Australia, affecting >10 Mha of arable sandy soils. The major symptom is dry patches of surface soil, even after substantial rainfall, directly affecting agricultural production through uneven crop and pasture germination, and reduced nutrient availability. In addition, staggered weed germination impedes effective weed control, and delayed crop and pasture germination increases the risk of wind erosion. Water repellency is caused by waxy organic compounds derived from the breakdown of organic matter mostly of plant origin. It is more prevalent in soils with a sandy surface texture; …

The Biosynthesis Of Allelopathic Di-C-Glycosylflavones From The Roots Of Desmodium Incanum (G. Mey.) Dc, Bing Hao, John C. Caulfield, Mary L. Hamilton, John A. Pickett, Charles A.O. Midega, Zeyaur R. Khan, Junru R. Wang, Antony M. Hooper

All Peer-Reviewed Publications

The allelopathic root exudate of the drought-tolerant subsistence cereal intercrop D. incanum, protecting against the parasitic weed Striga hermonthica, comprises a number of di-C-glycosylflavones specifically containing C-glucosyl, C-galactosyl and C-arabinosyl moieties. Here we demonstrate that the biosynthesis of all compounds containing a C-glucose involves C-glucosylation of 2-hydroxynaringenin with subsequent C-galactosylation, C-glucosylation or C-arabinosylation. In addition, the crude soluble enzyme extract converts two fluorinated 2-hydroxyflavanone analogues to corresponding mono- and di-C-glycosylflavones demonstrating that some differences in C-ring substitution can be tolerated by the plant enzymes. Elucidating the biosynthesis of these C-glycosylflavones (CGFs) has the potential to open up opportunities for transferring …

Evaluating The Sequential Masking Classification Approach For Improving Crop Discrimination In The Sudanian Savanna Of West Africa, Gerald Forkuor, Christopher Conrad, Michael Thiel, Tobias Landmann, Boubacar Barry

All Peer-Reviewed Publications

Classification of remotely sensed data to reveal the spatial distribution of crop types has high potential for improving crop area estimates and supporting decision making. However, remotely sensed crop maps still demand improvements as e.g. variations in farm management practices (e.g. planting and harvesting dates), soil and other environmental factors cause overlaps in features available for classification and thus confusion in error matrices. In this study, a variant of the sequential masking classification technique was applied to multi-temporal optical and microwave remote sensing data (RapidEye, Landsat, TerraSAR-X) to improve the accuracy of crop discrimination in West Africa. This approach employs …

Farmers' Control Practices Against The Invasive Red Spider Mite, Tetranychus Evansi Baker & Pritchard In Benin, Ginette Y. Azandémè-Hounmalon, Hippolyte D. Affognon, Françoise Assogba Komlan, Manuele Tamò, Komi K.M. Fiaboe, Serge Kreiter, Thibaud Martin

All Peer-Reviewed Publications

In 2008, the invasive tomato red spider mite Tetranychus evansi (Acari: Tetranychidae), a pest of solanaceous crops, was identified for the first time as the cause of serious damage on tomato (. Solanum lycopersicum L.; Solanaceae) crops in Benin. Since then, frequent outbreaks have been observed on Solanaceae and other leafy vegetables such as purple amaranth (. Amaranthus cruentus L.; Amaranthaceae) and bitter leaf (. Vernonia amygdalina D.; Asteraceae) in all growing areas in southern Benin. The objective of this study was to evaluate the intensity of damage by this invasive pest and the impact of farmers' control practices on …

Explorations In Advancing Microalgae Productivity, Peter Neofotis

Dissertations, Theses, and Capstone Projects

This thesis is part of an effort to advance microalgae cultivation for biofuel and high value products. The first chapters describe a large scale screening effort in which novel strains that hold great promise in large outdoor cultivation systems were isolated. Among these are strains of Scenedesmus obliquus, Borodinellopsis texensis, Chlorella sorokiniana, Ankistrodesmus, Coelastrella, and a previously uncharacterized species in the Chlamydomonadales. These species are characterized in terms of their phylogenetic relationship, biomass productivity, and, for some, lipid and carotenoid profiles under growth and stress conditions. Also discussed in regards to growth metabolism and oil …