Agricultural Science Commons^™

Using Multi-Spectral Imagery To Evaluate Corn Grown Under Nitrogen And Drought Stressed Conditions, Shannon L. Osborne, James S. Schepers, Mike R. Schlemmer

Department of Agronomy and Horticulture: Faculty Publications

The in-season estimation of crop stresses which have the potential of adversely affecting crop yield and/or quality could allow producers to make in-season management decisions to correct for the particular stress. A field study was conducted to evaluate the use of multispectral imagery for estimating corn (Zea mays L.) grain yield, in-season biomass and nitrogen (N) concentration under varying N and drought stresses. The experiment was a split-plot design with three replications using a factorial arrangement of treatments. Three irrigation (whole-plot) treatments included dry land, irrigation based on 0.5, and full evapotranspiration (ET). Sub-plot treatments included five N …

Expression Of A Putative Flavonoid 3'-Hydroxylase In Sorghum Mesocotyls Synthesizing 3-Deoxyanthocyanidin Phytoalexins, Jayanand Boddu, Catherine Svabek, Rajandeep Sekhon, Amanda Gevens, Ralph L. Nicholson, A. Daniel Jones, Jeffrey F. Pedersen, David L. Gustine, Surinder Chopra

Department of Agronomy and Horticulture: Faculty Publications

In sorghum, ingress of Cochliobolus heterostrophus stimulates the synthesis of 3-deoxyanthocyanidins that act as phytoalexins. Apigeninidin and luteolinidin are two major phytoalexins induced in the first 24 h after infection. In an attempt to understand genetic regulation of the biosynthesis of sorghum phytoalexins, we isolated a differentially expressed partial cDNA. Characterization and comparison showed that this cDNA sequence corresponds to a putative flavonoid 3’-hydroxylase. Full length sequence characterization allowed us to establish that the sorghum putative f3’h cDNA encodes a peptide of 517 amino acids that has domains conserved among cytochrome P450 proteins functioning in …

Field Evaluation Of Herbicides On Vegetables, Small Fruit, And Ornamental Crops 2003, Ronald E. Talbert, Brian V. Ottis, Mayank S. Malik, Andrew T. Ellis

Arkansas Agricultural Experiment Station Research Series

Herbicide evaluation studies on vegetables, small fruit, and ornamental crops were conducted in 2003 at the Arkansas Agricultural Experiment Station in Fayetteville, Ark., and the Vegetable Substation near Kibler, Ark., in an effort to evaluate new herbicides, herbicide mixtures, and their application timings for weed control efficacy and crop tolerance. Results of these studies, in part, provide useful information to producers, fellow researchers, the Crop Protection Industry, and the IR-4 Minor Crop Pest Management Program in the development of potential new herbicide uses in vegetable, fruit, and ornamental production.

Detection Of Moniliformin In Maize Using Capillary Zone Electrophoresis, C. M. Maragos

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

Moniliformin is a mycotoxin produced by certain fungi pathogenic to maize. It is capable of causing disease in domestic animals, possibly through inhibition of pyruvate dehydrogenase. Testing for MON commonly involves extraction of maize, isolation of moniliformin using solid-phase extraction columns and detection with high-performance liquid chromatography (HPLC) or gas chromatography. A capillary zone electrophoresisdiode array detection (CZE-DAD) method for determination of moniliformin in maize is reported. The extraction and isolation procedures are similar to those of a commonly used HPLC method, while the detection step requires only 10 min. Sixty-three samples of maize were tested by an established HPLC …

Levels And Changes Of Soil Phosphorus In Subtropical Beef Cattle Pastures, Gilbert C. Sigua, Mary J. Williams, Samuel W. Coleman

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

Long-term pasture management is believed to change soil chemical properties, but little is known about whether pasture management, such as fertilizer application, grazing, or haying can initiate such change in sandy and well-drained subtropical beef pastures. The objective of this study was to investigate the long term effect of pasture management (grazing+haying, GZ+HY) on soil phosphorus (P) dynamics (levels and changes) in subtropical beef cattle pastures with bahiagrass (BG, Paspalum notatum) and rhizoma peanut (RP, Arachis glabrata) with (WP) or without (WNP) P fertilization in Brooksville, FL from 1988 to 2000. Soil P dynamics in Subtropical Agricultural Research …

Aquaporins Are Observed In The Duct Epithelia Of The Epididymal Region Of The Large White Turkey, L. Zaniboni, V. Akuffo, M. R. Bakst

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

The cellular and molecular mechanisms regulating the reuptake of the testicular fluid supporting sperm exiting the testes in the bird are not known. The presence of aquaporins, proteins involved in transmembrane water transport, was investigated. Observations were limited to the ductuli efferentes, collecting ducts, and ductus epididymis. Interestingly all of these ducts were positive for aquaporins-2, -3, and -9 but not aquaporin- 7. When positive, aquaporin was observed localized over the whole cell or the apical plasma membrane of the nonciliated cells and the apical plasma membrane and cilia of the ciliated cells. This study is the first to clearly …

Plasma Clearance And Tissue Distribution Of Radiolabeled Leptin In The Chicken, John P. Mcmurtry, Christopher M. Ashwell, Donna M. Brocht, Thomas J. Caperna

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

Leptin is an adipose and liver tissue-derived secreted protein in chickens that has been implicated in the regulation of food intake and whole-body energy balance. In this study, the metabolic clearance and tissue uptake of leptin were examined in the chicken (Gallus gallus). Four-week-old broiler males were infused with ¹²⁵I-labeled mouse leptin. Chromatography of radiolabeled leptin in plasma produced two peaks, one at 16 kDa (free leptin) and a free iodine peak. No leptin binding protein in blood was detected. Leptin was cleared with a half-life estimate of 23 min. In order to investigate the tissue distribution …

Influence Of Different Cotton Fruit Sizes On Boll Weevil (Coleoptera: Curculionidae) Oviposition And Survival To Adulthoods., S. M. Greenberg, T. W. Sappington, M. Sétamou, R. J. Coleman

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

Understanding the critical host plant factors that determine oviposition behavior and survival of boll weevil, Anthonomus grandis grandis Boheman, on cotton, Gossypium hirsutum L., is important for developing successful pest management strategies. However, published information is both conflicting and limited regarding how different cotton fruit sizes affect boll weevil oviposition choices and subsequent larval survival to adulthood. Consequently, we used a standard based on fruit size diameter to evaluate boll weevil feeding and oviposition punctures, and survival to adulthood on 10 different cotton fruit sizes: squares of diameter 1.5-2.0 (pinhead), 3.0-3.5 (matchhead), 5-6, 7-8, or 9-10 mm; candle; and bolls …

Boll Weevil (Coleoptera: Curculionidae) Survival Through The Seed Cotton Cleaning Process In The Cotton Gin, Thomas W. Sappington, Alan D. Brashears, Megha N. Parajulee, Stanley C. Carroll, Mark D. Arnold, Roy V. Baker

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

There is concern that gins located in boll weevil, Anthonomus grandis grandis Boheman, eradication zones may become points of reintroduction when they process cotton grown in a neighboring infested area. We estimated boll weevil survival through two typical machine sequences used in commercial cotton gins to clean and dry the seed cotton in advance of the gin stand, as well as separately through two incline cylinder cleaners or one or two tower dryers operating at different temperatures. Large numbers of laboratory-reared adult boll weevils were marked with fluorescent powder, fed into the test system, and recovered with the assistance of …

Boll Weevil (Coleoptera: Curculionidae) Survival Through Cotton Gin Trash Fans, Thomas W. Sappington, Alan D. Brashears, Megha N. Parajulee, Stanley C. Carroll, Mark D. Arnold, Roy V. Baker

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

There is concern that cotton gins may serve as loci for reintroduction of boll weevils, Anthonomus grandis grandis Boheman, to eradicated or suppressed zones when processing weevil infested cotton from neighboring zones. Previous work has shown that virtually all weevils entering the gin in the seed cotton will be removed before they reach the gin stand. Those not killed by the seed cotton cleaning machinery will be shunted alive into the trash fraction, which passes through a centrifugal trash fan before exiting the gin. The objective of this study was to determine survival potential of boll weevils passed through a …

Registration Of Nineteen Waxy Spring Wheats, Robert A. Graybosch, E.J. Souza, W.A. Berzonsky, P. Stephen Baenziger, D.J. Mcvey, O.K. Chung

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

Nineteen spring waxy (amylose-free) wheat (Triticum aestivum L.) germplasm lines (Reg. no. GP-748 to GP-766, PI 619354–619357, 619359–619363, 619365–619369, 619371–619375) were developed and released by the ARS, USDA, and the Nebraska Agricultural Experiment Station in cooperation with the Agricultural Experiment Stations of North Dakota and Idaho in September 2002. Waxy wheats carry three non-functional (null) alleles (Wx-A1b, Wx-B1b, and Wx-D1b) at the genetic loci encoding the enzyme granule-bound starch synthase (GBSS, EC 2.4.1.21) (Nakamura et al., 1995). GBSS also is known as the “waxy” protein. Waxy wheats produce endospermstarch that is nearly devoid of amylose. Such starch …

Tillage And Cropping Effects On Soil Quality Indicators In The Northern Great Plains, Mark A. Liebig, D. L. Tanaka, Brian J. Wienhold

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

The extreme climate of the northern Great Plains of North America requires cropping systems to possess a resilient soil resource in order to be sustainable. This paper summarizes the interactive effects of tillage, crop sequence, and cropping intensity on soil quality indicators for two long-term cropping system experiments in the northern Great Plains. The experiments, located in central North Dakota, were established in 1984 and 1993 on a Wilton silt loam (FAO: Calcic Siltic Chernozem; USDA1: fine-silty, mixed, superactive frigid Pachic Haplustoll). Soil physical, chemical, and biological properties considered as indicators of soil quality were evaluated in spring 2001 in …

Geographic And Voltinism Differentiation Among North American Ostrinia Nubilalis (European Corn Borer) Mitochondrial Cytochrome C Oxidase Haplotypes, Brad S. Coates, Douglas V. Sumerford, Richard L. Hellmich

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

DNA sequence of European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), mitochondrial cytochrome c oxidase I (cox1) and II (cox2) genes were characterized and used for population genetic analysis. Twenty-six point mutations were identified from a 2,156 bp DNA sequence alignment. The frequency of polymorphic cox1 DdeI and HaeIII, and cox2 Sau3AI and MspI restriction sites were determined from 1,414 individuals by polymerase chain reaction restriction fragment length polymorphism. Ten haplotypes were observed. A single haplotype was present among 90% of individuals examined, and a HaeIII haplotype was not present in …

Habitat Manipulation Of The Apple Orchard Floor To Increase Ground-Dwelling Predators And Predation Of Cydia Pomonella (L.) (Lepidoptera: Tortricidae), Clarissa R. Mathews, Dale G. Bottrell, M. W. Brown

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

Augmenting generalist predator populations in new apple (Malus domestica Bork) plantings could potentially aid in the establishment of balanced orchard ecosystems that are less susceptible to pest outbreaks. Habitat can be an important factor in retaining predators in a system and can affect predator efficiency. We investigated the potential of increasing a complex of generalist ground-dwelling predators and enhancing biological control in a young 'Golden Delicious' apple orchard through ground habitat manipulation. We modified the orchard floor with four comparative habitat treatments: (1) detritus-rich compost mulch layer, (2) detritus-free synthetic mulch layer, (3) herbicide-treated vegetation thatch, and (4) bare …

Multiple Virus Infections In The Honey Bee And Genome Divergence Of Honey Bee Viruses, Yanping Chen, Yanping Zhao, John Hammond, Hei-Ti Hsu, Jay Evans, Mark Feldlaufea

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

Using uniplex RT-PCR we screened honey bee colonies for the presence of several bee viruses, including black queen cell virus (BQCV), deformed wing virus (DWV), Kashmir bee virus (KBV), and sacbrood virus (SBV), and described the detection of mixed virus infections in bees from these colonies. We report for the first time that individual bees can harbor four viruses simultaneously. We also developed a multiplex RT-PCR assay for the simultaneous detection of multiple bee viruses. The feasibility and specificity of the multiplex RT-PCR assay suggests that this assay is an effective tool for simultaneous examination of mixed virus infections in …

Comparison Of Production, Meat Yield, And Meat Quality Traits Of Nwac103 Line Channel Catfish, Norris Line Channel Catfish, And Female Channel Catfish × Male Blue Catfish F1 Hybrids, Brian G. Bosworth, William R. Wolters, Juan L. Silva, Roberto S. Chamul, Sinyoung Park

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

NWAC103 line channel catfish Ictalurus punctatus, Norris line channel catfish, and Norris line female channel catfish × Dycus Farm line male blue catfish I. furcatus F₁ hybrids were compared for production, meat yield, and meat quality traits. Juvenile fish from each genetic group were stocked at 12,000 fish/ha into three, 0.04-ha ponds per genetic group. Fish were fed once daily to satiation from June through October, and fed on days when afternoon water temperatures were above 17 °C from November through December. Fish were harvested, weighed, and counted in January, and 150 fish per genetic group (50 fish …

Molecular Mapping And Identification Of Soybean Fatty Acid Modifier Quantitative Trait Loci, D. L. Hyten Jr., Vincent R. Pantalone, Arnold M. Saxton, Michael E. Schmidt, Carl E. Sams

Department of Agronomy and Horticulture: Faculty Publications

Altering FA content in soybean [Glycine max (L.) Merr.] oil for improved functionality is a research goal of many soybean breeders. Several of the genes that alter palmitic, stearic, oleic, linoleic, and linolenic acids are modifier genes with small effects, causing these FA traits to act as quantitative traits. The objective of this study was to identify modifier FA quantitative trait loci (QTL) in soybean. A recombinant inbred line population was created from two prominent ancestors of currently avail-able U.S. cultivars (Essex and Williams) and grown in five environments. One hundred simple se-quence repeat markers spaced throughout the genome …

Implementation Of A Mitochondrial Mutator, Sally Mackenzie, Ricardo Vilela Abdelnoor

Department of Agronomy and Horticulture: Faculty Publications

Plant MSH1 polynucleotides and polypeptides are described. Also described are methods for the use and modulation of such MSH1 polynucleotides and polypeptides.

A Method To Detect Oxidative Stress By Monitoring Changes In The Extracellular Antioxidant Capacity In Plant Suspension Cells, C. Jacyn Baker, Norton M. Mock

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

Detection of H₂O₂ in the supernatant of plant suspension cells is often used to indicate the time and extent of the oxidative burst during interactions with either bacteria or pathogen-related elicitors. We have found that suspensions of plant cells, depending on conditions, may produce considerable levels of extracellular phenolics that can function as antioxidants and prevent or suppress the detection of H₂O₂. These compounds can be used as substrates by extracellular peroxidases to scavenge stoichiometric amounts of H₂O₂. When this occurs during plant/pathogen interactions it can mask both the …

Carbon Dioxide Dynamics During A Growing Season In Midwestern Cropping Systems, J. H. Prueger, J. L. Hatfield, T. B. Parkin, W.P. Kustas, T. C. Kaspar

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

Daily and seasonal CO₂-exchange dynamics between the boundary layer and biosphere is important to understanding Net Ecosystem Exchange of terrestrial ecosystems. Spatial and temporal variations of CO₂ fluxes across midwestern cropping systems have not been well documented. This study was designed to monitor and evaluate spatial and temporal dynamics of CO₂ exchange across a watershed region for typical production fields of corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] in the Midwest by quantifying the above-canopy, within-canopy, and soil components of C balance for this cropping system. An energy-balance approach using eddy …

Water Quality And The Grazing Animal, R. K. Hubbard, G. L. Newton, G. M. Hill

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

Grazing animals and pasture production can affect water quality both positively and negatively. Good management practices for forage production protect the soil surface from erosion compared with conventionally produced crops. Grazing animals and pasture production can negatively affect water quality through erosion and sediment transport into surface waters, through nutrients from urine and feces dropped by the animals and fertility practices associated with production of high-quality pasture, and through pathogens from the wastes. Erosion and sediment transport is primarily associated with high-density stocking and/ or poor forage stands. The two nutrients of primary concern relating to animal production are N …

Evaluation Of Adapted Wheat Cultivars For Tolerance To Pythium Root Rot, R. W. Higginbotham, T. C. Paulitz, K. A. Garland-Campbell, K. K. Kidwell

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

Genetic resistance in wheat (Triticum aestivum) against Pythium species would be an efficient means of control of this major root fungal pathogen, but so far no source has been identified. In addition, no long-term, sustainable options for controlling Pythium root rot are available; therefore, identifying and then incorporating genetic resistance into wheat cultivars would create an ideal method of control for this disease. The objective of this study was to examine the level of tolerance to Pythium root rot among a diverse set of wheat germ plasm collected from all major wheat production regions in the United States.

Elemental Uptake In Relation To Root Characteristics Of Tall Fescue, Glenn E. Shewmaker, Douglas A. Johnson, Henry F. Mayland, Scott A. Martin, Susie B. Hansen

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

HiMag, an accession of tall fescue (Festuca arundinacea Schreb.), was selected for high magnesium (Mg) concentration in leaves to reduce grass tetany risk to ruminants. However, the mechanism for enhanced Mg uptake in HiMag leaves has not been determined. The objective was to investigate if increased Mg uptake in HiMag could be explained by differences in elemental distribution among plant parts, root characteristics, or organic acid concentrations compared to its parental cultivars, ‘‘Kentucky 31’’ (KY31) and ‘‘Missouri 96’’ (MO96). The study was conducted on a surface-irrigated calcareous Portneuf silt loam (coarse-silty, mixed, mesic, Durinodic Xeric Haplocalcid). Vegetation and soil …

Betaine Improves Growth, But Does Not Induce Whole Body Or Hepatic Palmitate Oxidation In Swine (Sus Scrofa Domestica), Diane Wray-Cahen, Ignacio Fernández-Fígares, Erkki Virtanen, Norman C. Steele, Thomas J. Caperna

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

Dietary betaine may reduce carcass fat in growing pigs. We explored the effects of betaine on short-term growth and in vivo and in vitro fatty acid oxidation. Pigs were housed in metabolism crates and fed diets containing either 0% (control), 0.125% or 0.5% betaine at 80% of ad libitum energy intake. Fatty acid oxidation was measured during intravenous infusions of 1-¹³C-palmitate and in hepatocytes incubated in the presence or absence of betaine and carnitine. CO₂ and palmitate isotopic enrichments were determined by mass spectrometry. Pigs consuming 0.125% and 0.5% betaine for at least 9 days had growth …

Potential For Escape Of Live Boll Weevils (Coleoptera: Curculionidae) Into Cottonseed, Motes, And Cleaned Lint At The Cotton Gin, Thomas W. Sappington, Alan D. Brashears, Megha N. Parajulee, Stanley C. Carroll, Mark D. Arnold, Roy V. Baker

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

Reintroductions of the boll weevil, Anthonomus grandis grandis Boheman, into areas of the United States where it has been eradicated or suppressed are very expensive to mitigate. There is concern that a cotton gin in an eradication zone may serve as a site of boll weevil reintroductions when processing cotton harvested in a neighboring infested zone. Similarly, there is a question whether weevil-free areas can safely import gin products, such as cottonseed and baled lint, from infested areas without risking an introduction. Many countries require fumigation of imported U.S. cotton bales to protect against boll weevil introductions, costing the U.S. …

Case Study: Effects Of Delaying Implant And Programmed Rate Of Gain On Performance And Carcass Characteristics Of Yearling Beef Steers, G. Scaglia, L. W. Greene, F. T. Mccollum, N. A. Cole, T. H. Montgomery

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

Ninety-six steers (average BW = 335 ± 36 kg) were allotted in a completely randomized design with a 2 × 2 factorial arrangement of treatments. Factors were 1) implant on d 1 or no implant and 2) ad libitum access to feed on d 1 or programmed-fed for a target BW gain of 1.4 kg/d during the first 62 d of the feeding period. On d 63, all steers were implanted with Revalor-S^® (Hoechst Roussel Vet, Overland Park, KS) and provided ad libitum access to feed until harvest. From d 63 to 116, ADG and gain efficiency (g gain/kg …

Performance And Carcass Characteristics Of Feedlot Steers: Effects Of Delayed Implanting And Programmed Feeding During The Growing Period, G. Scaglia, L. W. Greene, F. T. Mccollum Iii, N. A. Cole, T. H. Montgomery

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

This experiment was conducted to determine the effect of programming the rate of gain and delaying the first implant in feedlot steers on feedlot performance and carcass characteristics. Ninety-six growing steers (269 ± 16.2 kg) were assigned to 12 pens in a completely randomized design. Treatments were implant (Synovex-S^®; 20 mg estradiol benzoate and 200 mg progesterone; Fort Dodge Animal Health, Overland Park, KS) on d 1 or no implant and programmed feeding to gain at a slow (0.68 kg/d) or fast (1.14 kg/d) rate during the growing period; these treatments were randomly assigned (n = 8) to …

Somatic Mutation-Mediated Evolution Of Herbicide Resistance In The Nonindigenous Invasive Plant Hydrilla (Hydrilla Verticillata) And Franck E. Dayan, Albrecht Michel, R. S. Arias, Brian E. Scheffler, Stephen O. Duke, Michael Netherland, Franck E. Dayan

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

Hydrilla (Hydrilla verticillata L.f. Royle) was introduced to the surface water of Florida in the 1950s and is today one of the most serious aquatic weed problems in the USA. As a result of concerns associated with the applications of pesticides to aquatic systems, fluridone is the only USEPA-approved chemical that provides systemic control of hydrilla. After a decrease in fluridone’s efficacy at controlling hydrilla, 200 Florida water bodies were sampled to determine the extent of the problem and the biological basis for the reduced efficacy. Our studies revealed that hydrilla phenotypes with two- to six-fold higher fluridone resistance …

Registration Of Three Partial Waxy Winter Wheats, Robert A. Graybosch, P. Stephen Baenziger

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

96MD7413-58 (Reg. no. GP-773, PI 617069), 96MD7413-36 (Reg. no. GP-774, PI 617070), and 96MD7110-71 (Reg. no. GP-775, PI 617071) partial waxy (reduced amylose) hard winter wheat (Triticum aestivum L.) germplasm lines were released by the ARS, USDA, and the Nebraska Agricultural Experiment Station in November 2002.

These partial waxy wheats carry non-functional (null) alleles (Wx-A1b and Wx-B1b) at two of the three hexaploid wheat Wx loci. These loci encode isoforms of the enzyme granule-bound starch synthase (GBSS, EC 2.4.1.21), also known as the “waxy” protein. Wheats with nonfunctional alleles at two loci are known as “double-nulls.” Double-null …

Putting Genes Into Genetic Coefficients, P. Stephen Baenziger, Gregory S. Mcmaster, Wallace Wilhelm, Albert Weiss

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

Plant parameters are critical inputs in crop simulation models and allow a general set of algorithms to represent features of specific cultivars. A subset of plant parameters is often referred to as "genetic coefficients". However, these genetic coefficients are developed from phenotypic observations, usually have a weak genetic basis, and are at best "genotypic" coefficients because they consider the genotype from a very integrative perspective and likely include some impact of environment on the trait or characteristic described. With increased understanding of crop genomes, we believe models can be improved by incorporating genetic coefficients that accurately describe the action of …