Horticulture Commons^™

Genetic Architecture Of Common Bunt Resistance In Winter Wheat Using Genome-Wide Association Study, Amira M. I. Mourad, Ahmed Sallam, Vikas Belamkar, Ezzat Mahdy, Bahy Bakheit, Atif Abo El-Wafaa, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Background: Common bunt (caused by Tilletia caries and T. foetida) has been considered as a major disease in wheat (Triticum aestivum) following rust (Puccinia spp.) in the Near East and is economically important in the Great Plains, USA. Despite the fact that it can be easily controlled using seed treatment with fungicides, fungicides often cannot or may not be used in organic and low-input fields. Planting common bunt resistant genotypes is an alternative.

Results: To identify resistance genes for Nebraska common bunt race, the global set of differential lines were inoculated. Nine differential lines carrying nine …

Root And Shoot Contribution To Carbon And Nitrogen Inputs In The Topsoil Layer In No-Tillage Crop Systems Under Subtropical Conditions, Marciel Redin, Sylvie Recous, Celso Aita, Bruno Chaves, Ismael Cristiano Pfeifer, Leonardo Mendes Bastos, Getulio Elias Pilecco, Sandro Jose Giacomini

Department of Agronomy and Horticulture: Faculty Publications

Recycling of carbon (C) and nitrogen (N) from plants into soils is decisive for maintaining soil organic matter and soil fertility. Therefore, we quantified plant biomass and C and N in the shoots and roots from the topsoil layer for a wide range of annual crops grown under subtropical conditions. We grew 26 species, 13 main crops, and 13 cover crops, in the field in standard sowing arrangements. Root biomass was recovered from the 0.00-0.20 m soil layer at flowering, and shoot biomass was measured at flowering for all crops and at maturity only for the main crops. Root dry …

Improving Fertilizer Recommendations For Nepalese Farmers With The Help Of Soil-Testing Mobile Van, Sunil Pandey, Netra Prasad Bhatta, Prakash Paudel, Rajan Pariyar, Kiran Hari Maskey, Janardan Khadka, Tuk Bahadur Thapa, Balaram Rijal, Dinesh Panday

Department of Agronomy and Horticulture: Faculty Publications

Smallholder farmers dominate agriculture in Nepal. These farmers have poor knowledge about agriculture and lack of support for soil management and integrated plant-nutrient systems. Focusing on the importance and need for soil-fertility management, a soil-testing mobile van program has recently been introduced in Nepal by Soil Management Directorate, Hariharbhawan. With the introduction of the mobile lab, famers can get their soil tested for nutrient deficiencies and fertilizer requirements at their doorsteps. Using mobile lab, spatial distributions of chemical properties, including pH, organic matter (OM), total nitrogen (N), available phosphorus (as P₂O₅), and available potassium (as K …

Genotype Imputation In Winter Wheat Using First-Generation Haplotype Map Snps Improves Genome-Wide Association Mapping And Genomic Prediction Of Traits, Moses Nyine, Shichen Wang, Kian Kiani, Katherine Jordan, Shuyu Liu, Patrick Byrne, Scott Haley, Stephen Baenziger, Shiaoman Chao, Robert Bowden, Eduard Akhunov

Department of Agronomy and Horticulture: Faculty Publications

Genome-wide single nucleotide polymorphism (SNP) variation allows for the capture of haplotype structure in populations and prediction of unobserved genotypes based on inferred regions of identity-by-descent (IBD). Here we have used a first-generation wheat haplotype map created by targeted re-sequencing of low-copy genomic regions in the reference panel of 62 lines to impute marker genotypes in a diverse panel of winter wheat cultivars from the U.S. Great Plains. The IBD segments between the reference population and winter wheat cultivars were identified based on SNP genotyped using the 90K iSelect wheat array and genotyping by sequencing (GBS). A genome-wide association study …

Genome-Wide Association Study Reveals Novel Genomic Regions Associated With 10 Grain Minerals In Synthetic Hexaploid Wheat, Madhav Bhatta, P. Stephen Baenziger, Brian M. Waters, Rachana Poudel, Vikas Belamkar, Jesse Poland, Alexey Morgounov

Department of Agronomy and Horticulture: Faculty Publications

Synthetic hexaploid wheat (SHW; Triticum durum L. x Aegilops tauschii Coss.) is a means of introducing novel genes/genomic regions into bread wheat (T. aestivum L.) and a potential genetic resource for improving grain mineral concentrations. We quantified 10 grain minerals (Ca, Cd, Cu, Co, Fe, Li, Mg, Mn, Ni, and Zn) using an inductively coupled mass spectrometer in 123 SHWs for a genome-wide association study (GWAS). A GWAS with 35,648 single nucleotide polymorphism (SNP) markers identified 92 marker-trait associations (MTAs), of which 60 were novel and 40 were within genes, and the genes underlying 20 MTAs had annotations suggesting …

Stolon Development And Cultural Production Practices Of Winter-Grown Strawberries, Donna M. Morrison, Erin Blankenship, Paul Read, Ellen Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

The four experiments described here are part of a 5-year program focused on determining whether day-neutral and short-day strawberries would be suitable for commercial offseason/ winter (temperate climate) production in greenhouses. All research was performed using container-grown plants fertigated through a capillary mat production system with heat supplied under the benches. The first experiment focused on stolon development. The second experiment investigated the influence of stolon removal on berry production and included the removal of flowers for the first three weeks. The third and fourth experiments were conducted as a comparison of university research (experiment 3) versus a commercial operation …

Wildland Fire Science Literacy: Education, Creation, And Application, Devan Allen Mcgranahan, Carissa L. Wonkka

Department of Agronomy and Horticulture: Faculty Publications

Wildland fire science literacy is the capacity for wildland fire professionals to understand and communicate three aspects of wildland fire: (1) the fundamentals of fuels and fire behavior, (2) the concept of fire as an ecological regime, and (3) multiple human dimensions of wildland fire and the socio-ecological elements of fire regimes. Critical to wildland fire science literacy is a robust body of research on wildland fire. Here, we describe how practitioners, researchers, and other professionals can study, create, and apply robust wildland fire science. We begin with learning and suggest that the conventional fire ecology canon include detail on …

An Exome-Seq Based Tool For Mapping And Selection Of Candidate Genes In Maize Deletion Mutants, Shangang Jia, Kyla Morton, Chi Zhang, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Despite the large number of genomic and transcriptomic resources in maize, there is still much to learn about the function of genes in developmental and biochemical processes. Some maize mutants that were generated by gamma-irradiation showed clear segregation for the kernel phenotypes in B73 X Mo17 F2 ears. To better understand the functional genomics of kernel development, we developed a mapping and gene identification pipeline, bulked segregant exome sequencing (BSEx-seq), to map mutants with kernel phenotypes including opaque endosperm and reduced kernel size. BSEx-seq generates and compares the sequence of the exon fraction from mutant and normal plant F2 DNA …

Genetic Architecture Of Soybean Yield And Agronomic Traits, Brian W. Diers, Jim Specht, Katy Martin Rainey, Perry Cregan, Qijian Song, Vishnu Ramasubramanian, George Graef, Randall L. Nelson, William Schapaugh, Dechun Wang, Grover Shannon, Leah Mchale, Stella K. Kantartzi, Alencar Xavier, Rouf Mian, Robert M. Stupar, Jean-Michel Michno, Yong-Qiang Charles An, Wolfgang Goettel, Russell Ward, Carolyn Fox, Alexander E. Lipka, David Hyten, Troy Cary, William D. Beavis

Department of Agronomy and Horticulture: Faculty Publications

Soybean is the world’s leading source of vegetable protein and demand for its seed continues to grow. Breeders have successfully increased soybean yield, but the genetic architecture of yield and key agronomic traits is poorly understood. We developed a 40-mating soybean nested association mapping (NAM) population of 5,600 inbred lines that were characterized by single nucleotide polymorphism (SNP) markers and six agronomic traits in field trials in 22 environments. Analysis of the yield, agronomic, and SNP data revealed 23 significant marker-trait associations for yield, 19 for maturity, 15 for plant height, 17 for plant lodging, and 29 for seed mass. …

Influence Of Harvest Date On Seed Yield And Quality In Forage Kochia, Cody F. Creech, Blair L. Waldron, Corey V. Ransom, Dale R. Zobell, Joseph Earl Creech

Department of Agronomy and Horticulture: Faculty Publications

Forage kochia (Bassia prostrata) is used for rangeland reclamation and livestock and wildlife forage, but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies virescens and grisea. Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most accessions. Cultivar Snowstorm and breeding line Sahsel, both subsp. grisea, had the greatest 100-seed weights in November, 155 …

Maize And Soybean Root Front Velocity And Maximum Depth In Iowa, Usa, Raziel A. Ordóñez, Michael J. Castellano, J. L. Hatfield, M. J. Helmers, Mark A. Licht, Matt Liebman, Ranae Dietzel, Rafael Martinez-Feria, Javed Iqbal, Laila A. Puntel, S. Carolina Córdova, Kaitlin Togliatti, Emily E. Wright, Sotirios V. Archontoulis

Department of Agronomy and Horticulture: Faculty Publications

Quantitative measurements of root traits can improve our understanding of how crops respond to soil and weather conditions, but such data are rare. Our objective was to quantify maximum root depth and root front velocity (RFV) for maize (Zea mays) and soybean (Glycine max) crops across a range of growing conditions in the Midwest USA. Two sets of root measurements were taken every 10–15 days: in the crop row (in-row) and between two crop rows (center-row) across six Iowa sites having different management practices such as planting dates and drainage systems, totaling 20 replicated experimental treatments. …

Sequences Involved In Plant Yield And Methods Of Using, Harkamal Walia, Dante Placido, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Nucleic acid sequences involved in plant yield are provided, as are methods of using such nucleic acid sequences .

Identification Of Quantitative Trait Loci Conferring Resistance To Tan Spot In A Biparental Population Derived From Two Nebraska Hard Red Winter Wheat Cultivars, Gayan K. Kariyawasam, Waseem Hussain, Amanda Easterly, Mary Guttieri, Vikas Belamkar, Jesse Poland, Jorge Venegas, Stephen Baenziger, Francois Marais, Jack B. Rasmussen, Zhaohui Liu

Department of Agronomy and Horticulture: Faculty Publications

Tan spot, caused by Pyrenophora triticirepentis (Ptr), is a destructive foliar disease in all types of cultivated wheat worldwide. Genetics of tan spot resistance in wheat is complex, involving insensitivity to fungal-produced necrotrophic effectors (NEs), major resistance genes, and quantitative trait loci (QTL) conferring race-nonspecific and race-specific resistance. The Nebraska hard red winter wheat (HRWW) cultivar ‘Wesley’ is insensitive to Ptr ToxA and highly resistant to multiple Ptr races, but the genetics of resistance in this cultivar is unknown. In this study, we used a recombinant inbred line (RIL) population derived from a cross between Wesley and another …

Improving An Active-Optical Reflectance Sensor Algorithm Using Soil And Weather Information, G. M. Bean, N. R. Kitchen, J. J. Camberato, R. B. Ferguson, F. G. Fernandez, D. W. Franzen, C. A. M. Laboski, E. D. Nafziger, J. E. Sawyer, P. C. Scharf, J. Schepers, J. S. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Active-optical reflectance sensors (AORS) use light reflectance characteristics from a crop canopy as an indicator of the plant’s N health. However, studies have shown AORS algorithms used in conjunction with measured reflectance characteristics for corn (Zea mays L.) N fertilizer rate recommendations are not consistently accurate. Our objective was to determine if soil and weather information could be utilized with an AORS algorithm developed at the University of Missouri (ALG_MU) to improve in-season (~V9 corn development stage) N fertilizer recommendations. Nitrogen response trials were conducted across eight states over three growing seasons, totaling 49 sites with soils …

Active-Optical Reflectance Sensing Corn Algorithms Evaluated Over The United States Midwest Corn Belt, G. M. Bean, N. R. Kitchen, J. J. Camberato, R. B. Ferguson, F. G. Fernandez, D. W. Franzen, C. A. M. Laboski, E. D. Nafziger, J. E. Sawyer, P. C. Scharf, J. Schepers, J. S. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Uncertainty exists with corn (Zea mays L.) N management due to year-to-year variation in crop N need, soil N supply, and N loss from leaching, volatilization, and denitrification. Activeoptical reflectance sensing (AORS) has proven effective in some fields for generating N fertilizer recommendations that improve N use efficiency, but locally derived (e.g., within a US state) AORS algorithms have not been tested simultaneously across a broad region. The objective of this research was to evaluate locally developed AORS algorithms across the US Midwest Corn Belt region for making in-season corn N recommendations. Forty-nine N response trials were conducted across …

Lignocellulosic-Based Bioenergy And Water Quality Parameters: A Review, Bharat Sharma Acharya, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

High rates of crop residue removal as biofuel feedstocks could increase losses of nonpoint source pollutants, negatively affecting water quality. An alternative to residue removal can be growing dedicated bioenergy crops such as warm season grasses (WSGs) and short-rotation woody crops (SRWCs). Yet, our understanding of the implications of growing dedicated bioenergy crops on water quality is limited. Thus, we (i) synthesized and compared the impacts of crop residue removal, WSGs, and SRWCs on water quality parameters (i.e., sediment and nutrient runoff, and nutrient leaching) and (ii) identified research gaps for growing dedicated energy crops. Literature indicates that residue removal …

Hops On A Quarter-Acre, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

This publication presents information on how to develop a quarter-acre hop yard, suitably sized to explore the unique production methods associated with this specialty crop. Emerging growers with an interest in growing hop should gain knowledge about its unique plant growth and development, culture, common pests and diseases, and harvest handling. Using information in this publication, growers should be able to experiment with hop production and harvesting so that they can develop a measured vision for future production of this crop.

Epigenomic Plasticity Of Arabidopsis Msh1 Mutants Under Prolonged Cold Stress, Sunil Kumar Kenchanmane Raju, Mon-Ray Shao, Yashitola Wamboldt, Sally A. Mackenzie

Department of Agronomy and Horticulture: Faculty Publications

Dynamic transcriptional and epigenetic changes enable rapid adaptive benefit to environmental fluctuations. However, the underlying mechanisms and the extent to which this occurs are not well known. MutS Homolog 1 (MSH1) mutants cause heritable developmental phenotypes accompanied by modulation of defense, phytohormone, stress‐response, and circadian rhythm genes, as well as heritable changes in DNA methylation patterns. Consistent with gene expression changes, msh1 mutants display enhanced tolerance for abiotic stress including drought and salt stress, while showing increased susceptibility to freezing temperatures. Despite changes in defense and biotic stress‐response genes, msh1 mutants showed increasing susceptibility to the bacterial pathogen Pseudomonas syringae. …

Can Bangladesh Produce Enough Cereals To Meet Future Demand?, J. Timsina, J. Wolf, N. Guilpart, L G. J. Van Bussel, P. Grassini, J. Van Wart, A. Hossain, H. Rashid, S. Islam, M. K. Van Ittersum

Department of Agronomy and Horticulture: Faculty Publications

Bangladesh faces huge challenges in achieving food security due to its high population, diet changes, and limited room for expanding cropland and cropping intensity. The objective of this study is to assess the degree to which Bangladesh can be self-sufficient in terms of domestic maize, rice and wheat production by the years 2030 and 2050 by closing the existing gap (Yg) between yield potential (Yp) and actual farm yield (Ya), accounting for possible changes in cropland area. Yield potential and yield gaps were calculated for the three crops using well-validated crop models and site-specific weather,management and soil data, and upscaled …

Parallel Altitudinal Clines Reveal Trends In Adaptive Evolution Of Genome Size In Zea Mays, Paul Bilinski, Patrice S. Albert, Jeremy J. Berg, James A. Birchler, Mark N. Grote, Anne Lorant, Juvenal Quezada, Kelly Swarts, Jinliang Yang, Jeffrey Ross-Ibarra

Department of Agronomy and Horticulture: Faculty Publications

While the vast majority of genome size variation in plants is due to differences in repetitive sequence, we know little about how selection acts on repeat content in natural populations. Here we investigate parallel changes in intraspecific genome size and repeat content of domesticated maize (Zea mays) landraces and their wild relative teosinte across altitudinal gradients in Mesoamerica and South America. We combine genotyping, low coverage whole-genome sequence data, and flow cytometry to test for evidence of selection on genome size and individual repeat abundance. We find that population structure alone cannot explain the observed variation, implying that …