Life Sciences Commons^™

Greenhouse Gas Emissions And Soil Indicators Four Years After Manure And Compost Applications, Daniel Ginting, Anabayan Kessavalou, Bahman Eghball, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Understanding how carbon, nitrogen, and key soil attributes affect gas emissions from soil is crucial for alleviating their undesirable residual effects that can linger for years after termination of manure and compost applications. This study was conducted to evaluate the emission of soil CO₂, N₂O, and CH₄ and soil C and N indicators four years after manure and compost application had stopped. Experimental plots were treated with annual synthetic N fertilizer (FRT), annual and biennial manure (MN1 and MN2, respectively), and compost (CP1 and CP2, respectively) from 1992 to 1995 based on removal of 151 …

Forage Yield And Economic Losses Associated With The Brown-Midrib Trait In Sudangrass, M. D. Casler, Jeffrey F. Pedersen, D. J. Undersander

Department of Agronomy and Horticulture: Faculty Publications

Brown-midrib genes increase digestibility due to reduced lignification in sudangrass, Sorghum bicolor subsp. drummondii (Nees ex Steud.) de Wet & Harlan. Brown-midrib lines are known to be low in forage yield potential, but this reduction in forage yield has not been previously quantified. The objectives of this study were to quantify the increase in forage quality and decrease in forage yield and to provide an economic assessment of this dichotomy. Piper and Greenleaf (normal leaves) were compared with their brown-midrib counterparts and four highly selected brown-midrib (FG) lines at two locations for 2 yr. Brown-midrib lines averaged 9.0% lower in …

A Century Of American Viticulture, Paul Read, Sanjun Gu

Department of Agronomy and Horticulture: Faculty Publications

To review the work reported on a crop that "comes to us out of the abyss of antiquity" (Winker, 1965) is a Herculean task impossible to accomplish within the scope of this review. Therefore, to honor the first century of the American Society for Horticultural Science (ASHS), this review will focus on selected viticulture literature published from 1903 to 2002. Of necessity, some topics will be omitted or only briefly treated.

The culture of grapevines (Vitis spp.) apparently began in the Transcaucasus region, principally between the Black and Caspian seas, where the classical wine and table grape Vitis vinifera …

Agriculture -Related Science And Technology Priorities For Poverty Reduction And Sustainable Development In Developing Countries To 2020, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Alleviation of poverty in developing countries depends on four factors: (1) supportive political, social, and economic environments that foster investments in infrastructure, enterprises, markets, and natural resource conservation, (2) sustainable development and income growth, (3) a continued decline in population growth rates such that the human population ultimately stabilizes at about 9-10 billion people by 2050, (4) access to affordable and nutritious food supply. Of these, the CGIAR system of research centers have a comparable advantage in contributing to sustainable development and income growth by ensuring adequate food production in systems that conserve natural resources and protect environmental quality. To …

Variability And Relationships Among 12-Hour Ivdmd, Starch, Oil, Protein, And Physical Characteristics Of 16 Sorghum Conversion Lines, Jeffrey F. Pedersen, Kenneth D. Kofoid

Department of Agronomy and Horticulture: Faculty Publications

A factor frequently identified as a key to understanding sorghum [Sorghum bicolor (L.) Moench] feed value to ruminant animals is rate of starch digestion. Recent research in corn (Zea mays L.) has established a strong ability to predict rumen starch degradation from grain physical and chemical parameters. It was therefore important to determine whether similar relationships could be established in sorghum. The objectives of this study were to determine: 1) range of variation for 12-hour in vitro dry matter disappearance (IVDMD), chemical, and physical grain quality parameters among 16 sorghum conversion lines; and 2) to establish the strength …

A Major Qtl For Common Bacterial Blight Resistance Derives From The Common Bean Great Northern Landrace Cultivar Montana No. 5, Phillip N. Miklas, Dermot Coyne, Kenneth F. Grafton, Nedim Mutlu, Jim Reiser, Dale Lindgren, Shree Singh

Department of Agronomy and Horticulture: Faculty Publications

Knowledge of the evolutionary origin and sources of pest resistance genes will facilitate gene deployment and development of crop cultivars with durable resistance. Our objective was to determine the source of common bacterial blight (CBB) resistance in the common bean Great Northern Nebraska #1 (GN#1) and GN#1 Selection 27 (GN#1 Sel 27). Several great northern cultivars including GN#1, GN#1 Sel 27, and Montana No. 5 (the female parent of the common x tepary bean interspecific population from which GN #1 and GN # 1 Sel 27 were derived) and known susceptible checks were evaluated for CBB reaction in field and …

The S-Locus And Unilateral Incompatibility, C. Nathan Hancock, Katsuhiko Kondo, Brian Beecher, Bruce Mcclure

Department of Agronomy and Horticulture: Faculty Publications

Plants have many ways to regulate the type of pollen that arrives on the stigma surface. Once there, further control mechanisms regulate compatibility. The latter controls are largely based on biochemical interactions that support compatible pollination and prevent incompatible matings. S-RNase-based selfincompatibility (SI) systems are the most phylogenetically widespread mechanisms for controlling pollination. Studies of Nicotiana establish a firm link between SI and unilateral interspecific incompatibility. Although implicated in both inter- and intraspecific compatibility, S-RNase operates through at least three distinct genetic mechanisms that differ in their dependence on non-S-RNase factors. Identification and characterization of these non-S-RNase factors is currently …

Understanding Corn Yield Potential In Different Environments, Achim R. Dobermann, Timothy J. Arkebauer, Kenneth G. Cassman, Rhae A. Drijber, John L. Lindquist, James E. Specht, Daniel T. Walters, Haishun Yang, Daniel N. Miller, Darren L. Binder, Gregory J. Teichmeier, Richard B. Ferguson, Charles S. Wortmann

Department of Agronomy and Horticulture: Faculty Publications

The UNL research program on Ecological intensification of irrigated maize-based cropping systems aims to (i) improve understanding of the yield potential of corn and soybean and how it is affected by management, (ii) develop a scientific basis for evaluating yield potential at different locations, (iii) develop practical technologies for managing intensive cropping systems at 70-80% of the yield potential, and (iv) conduct integrated assessment of productivity, profitability, input use efficiency, soil carbon sequestration, energy and carbon budgets, and trace gas emissions. Results of this work have been reported earlier (Arkebauer et al., 2001; Dobermann et al., 2002). In …

Comparison And Hybridization Of Two Approaches For Maize Simulation, Haishun Yang, Kenneth G. Cassman, Achim R. Dobermann, Daniel T. Walters, John L.. Lindquist, Timothy J. Arkebauer

Department of Agronomy and Horticulture: Faculty Publications

Two approaches dominate simulation modeling of maize growth: (1) a generic approach, represented by the family of crop models developed by Dutch scientists at the Wageningen University, e.g. SUCROS (Spitters et al, 1989), WOFOST (Diepen et al, 1989) and INTERCOM (Kropff and van Laar, 1993), and (2) a maize-specific approach, represented by CERES-Maize (Jones and Kiniry, 1986) and its derivatives such as the maize module in DSSAT, and the MSB model developed by Muchow et al. (Muchow et al, 1990). These two approaches differ in three aspects. First, maize development in generic models is driven primarily by availability of …

Growing Corn In A Computer: The Hybrid Hybrid-Maize Simulation Model And Its Application To Production Agriculture, Achim R. Dobermann, Haishun Yang

Department of Agronomy and Horticulture: Faculty Publications

Outline

Yield potential and yield gaps

To achieve yield potential of an environment

Hybrid Hybrid-Maize model

Hybrid Hybrid-Maize validation

Potential applications

EI Lincoln, NE: 2003 Yields

What determines spatial variation in corn yield potential in Nebraska?

Simulated attainable corn yields in different regions of Nebraska

To achieve full climatic site yield potential, management requires:

Optimal management: gain in season length

Corn yield potential in 2003

Potential applications

Summary

Outlook

A Simulation Approach For Evaluating Maize Yield Potential In Different Environments, Haishun S. Yang, Achim R. Dobermann, Kenneth G. Cassman, Daniel T. Walters, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

What is yield potential?

To achieve yield potential of an environment:

Why yield potential important?

Objectives:

Nebraska (NE):

To estimate yield potential across NE requires:

How to estimate yield potential across NE?

Choice of model: Hybrid-Maize

Simulation of best yields under current practices

Current practices: best yields

Current practices: variation of best yields

To achieving full yield potential:

Optimal management: gain in season length

Optimal management: gain in yield

Optimal management: temporal (mean=14 y) variation of yields

Conclusions

Genetic And Environmental Effects On Dough Mixing Characteristics And Agronomic Performance Of Diverse Hard Red Winter Wheat Genotypes, Hikmet Budak, P. Stephen Baenziger, Robert A. Graybosch, B. S. Beecher, Kent M. Eskridge, M. J. Shipman

Department of Agronomy and Horticulture: Faculty Publications

Wheat (Triticum aestivum L.) genotypes with short mixing times usually have low mixing tolerance values, which make them more ,sensitive to over mixing in commercial bread production. In this study, we evaluated the genotypic and environmental effects on agronomic performance and end-use quality of 27 experimental genotypes (hereafter referred to as mixing tolerant genotypes) which were identified in an initial screen as having short mixing times and good mixing tolerances to 1) determine whether genotypes identified in a preliminary end-use quality screen as lines with usually long tolerances but short mixing times were due to their genotype (G), the …

Nutrition Of Floricultural Crops: How Far Have We Come?, Ellen T. Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

According to Seeley (1979), even though the Society for Horticultural Science was formed in 1903, it wasn't until the 1930s that research papers on the subject of floriculture were published in our journal. There were, however, numerous college and university bulletins about floricultural crops which included fertilizer studies (for example, Blake, 1915).

Despite the sluggish start, in the last 25 years, in the American Society of Horticultural Science's three journals (Journal of the American Society for Horticultural Science, HortScience, and HortTechnology) alone, there have been over 240 publications relating to the nutrition of floricultural crops. Journal such as …

Registration Of ‘Ne422t’ Winter Triticale, P. Stephen Baenziger, K. P. Vogel

Department of Agronomy and Horticulture: Faculty Publications

NE422T triticale (X Triticosecale Wittmack) (Reg. no CV-27, PI 629028) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS. It was jointly released in 2001 by the developing institutions. NW422T was selected from the cross ‘Trical’/‘UB-UW26’ where Trical is most likely ‘Trical 100’ (a forage triticale developed by Resource Seed Inc., a subsidiary of Goldsmith Seed Company, Gilroy, CA) and UB-UW26 is an unknown winter triticale germplasm line given to the breeding program in the 1980s.The cross was made in 1990. The F₁ generation was grown in the greenhouse in 1990-1991. The F₂ and F …

Detection Of Phosphorus And Nitrogen Deficiencies In Corn Using Spectral Radiance Measurements, S.L. Osbourne, James S. Schepers, D. Francis, Michael R. Schlemmer

Department of Agronomy and Horticulture: Faculty Publications

Applications of remote sensing in crop production are becoming increasingly popular due in part to an increased concern with pollution of surface and ground waters due to over-fertilization of agricultural lands and the need to compensate for spatial variability in a field. Past research in this area has focused primarily on N stress in crops. Other stresses and the interactions have not been fully evaluated. A field experiment was conducted to determine wavelengths and/or combinations of wavelengths that are indicative of P and N deficiency and also the interaction between these in corn (Zea mays L.). The field experiment …

Understanding And Managing Corn Yield Potential, Achim R. Dobermann, Timothy J. Arkebauer, Kenneth G. Cassman, J Lindquist, James E. Specht, Daniel T. Walters, Haishun Yang

Department of Agronomy and Horticulture: Faculty Publications

Rainfed and irrigated systems in which corn is grown either in rotation with soybean or as a continuous monocrop are the predominant cropping systems in North America. About 30 million ha of corn are harvested annually for grain in the USA, of which eleven states in the Corn Belt produce more than 210 million tons or 35% of the global corn supply (Dobermann and Cassman, 2002). During the past 35 years, average corn yields have increased linearly at a rate of 1.7 bu/acre per year (109 kg ha^-1 per year, Fig. 1). Average corn yields now approach 140 bu/acre …

Soil Properties As Influenced By Phosphorus- And Nitrogen-Based Manure And Compost Applications, Bahman Eghball

Department of Agronomy and Horticulture: Faculty Publications

Manure or compost application based on N needs of corn (Zea mays L. ) may result in soil accumulation of P, N, and other ions, since the manure or compost N/P ratio is usually smaller than the corn N/P uptake ratio. This study was conducted from 1992 to 1996 to evaluate the effects of annual or biennial application of N- and P-based composted and noncomposted beef cattle (Bos taurus ) feed- lot manure on soil properties. Fertilized and unfertilized checks were also included. Soil surface (0–15 cm) pH significantly increased with N-based manure (MN) or compost application (CN), …

Characterization Of Fro1, A Pea Ferric-Chelate Reductase Involved In Root Iron Acquisition, Brian M. Waters, Dale G. Blevins, David J. Eide

Department of Agronomy and Horticulture: Faculty Publications

To acquire iron, many plant species reduce soil Fe(III) to Fe(II) by Fe(III)-chelate reductases embedded in the plasma membrane of root epidermal cells. The reduced product is then taken up by Fe(II) transporter proteins. These activities are induced under Fe deficiency. We describe here the FRO₁ gene from pea (Pisum sativum), which encodes an Fe(III)-chelate reductase. Consistent with this proposed role, FRO₁ shows similarity to other oxidoreductase proteins, and expression of FRO₁ in yeast conferred increased Fe(III)-chelate reductase activity. Furthermore, FRO₁ mRNA levels in plants correlated with Fe(III)-chelate reductase activity. Sites of FRO_{1 …}

Accumulation Of Microbial Biomass Within Particulate Organic Matter Of Aging Golf Greens, Mine Kerek, Rhae A. Drijber, William L. Powers, Robert C. Shearman, Roch E. Gaussoin, Anne Streich

Department of Agronomy and Horticulture: Faculty Publications

Microbial biomass (MB) is a key variable controlling soil organic matter dynamics in soil. Currently, there is little information on the amount and significance of MB in highly managed golf greens. Our objective was to determine the amount and distribution of MB within soil structural components of golf greens and its relationship to the location of organic substrates. During 1996, 47 greens were sampled from 12 golf courses within Nebraska (USA). Microbial biomass, determined as extractable lipid phosphate on field-moist soils, increased linearly with age of green (Y = 19.39 + 3.54x; r² = 0.87, P = 0.001). In …

Agroecosystems, Nitrogen-Use Efficiency, And Nitrogen Management, Kenneth G. Cassman, Achim R. Dobermann, Daniel T. Walters

Department of Agronomy and Horticulture: Faculty Publications

The global challenge of meeting increased food demand and protecting environmental quality will be won or lost in cropping systems that produce maize, rice, and wheat. Achieving synchrony between N supply and crop demand without excess or deficiency is the key to optimizing trade-offs amongst yield, profit, and environmental protection in both large-scale systems in developed countries and small-scale systems in developing countries. Setting the research agenda and developing effective policies to meet this challenge requires quantitative understanding of current levels of N-use efficiency and losses in these systems, the biophysical controls on these factors, and the economic returns from …

Seasonal Dynamics Of Prairie Sandreed Rhizome Development, Patrick E. Reece, Jennifer S. Nixon, Lowell E. Moser, Steven S. Waller

Department of Agronomy and Horticulture: Faculty Publications

Multiple generations of rhizome-connected tillers stabilize soils and produce measurable amounts of herbage on sandy rangeland throughout the world. However, little is known about the dynamics of rhizome development in these clonal plant species. Seasonal relationships between foliar characteristics and rhizomes of prairie sandreed [Calamovilfa longifolia (Hook) Scribn.] were examined on sands range sites at 30-day intervals from May through September 1989 and 1990 at the University of Nebraska, Panhandle Experimental Range near Scottsbluff. Quadrats were excavated each year from two, 5 x 5 Latin Square macroplots in each of 2 grazing histories, long-term rest or current-year deferment. Under …

Biosolids As Nitrogen Source For Irrigated Maize And Rainfed Sorghum, Darren L. Binder, Achim Dobermann, Donald H. Sander, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

We quantified effects of anaerobically digested sewage sludge (bio- solids) on yield, N use efficiency, and soil NO3 over a period of 4 yr. Field experiments with five biosolids rates and six N rates were conducted at two sites on a silty clay loam soil: one with irrigated maize (Zea mays L.) and another site with rainfed sorghum (Sorghum bicolor L.). Biosolids rates for achieving maximum yields in the year of application were 62 Mg ha^-1 (441 kg organic N ha^-1) on irrigated maize and 36 Mg ha^-1 (257 kg organic N ha^{-1 …}

Use Of Spectral Radiance To Estimate In-Season Biomass And Grain Yield In Nitrogen- And Water-Stressed Corn, S.L. Osborne, James S. Schepers, D.D. Francis, Michael R. Schlemmer

Department of Agronomy and Horticulture: Faculty Publications

Current technologies for measuring plant water status are limited, while recently remote sensing techniques for estimating N status have increased with limited research on the interaction between the two stresses. Because plant water status methods are time-consuming and require numerous observations to characterize a field, managers could benefit from remote sensing techniques to assist in irrigation and N management decisions. A 2-yr experiment was initiated to determine specific wavelengths and/or combinations of wavelengths indicative of water stress and N deficiencies, and to evaluate these wavelengths for estimating in-season biomass and corn (Zea mays L.) grain yield. The experiment was …

Corn Yield Potential And Optimal Soil Productivity In Irrigated Corn/Soybean Systems, Achim R. Dobermann, Timothy J. Arkebauer, Kenneth G. Cassman, Rhae A. Drijber, J. Lindquist, S. Madhaven, John P. Markwell, Lenis Alton Nelson, James E. Specht, Daniel T. Walters, Haishun Yang, Brigid Amos, Darren L. Binder, C. Murphy, Gregory J. Teichmeier

Department of Agronomy and Horticulture: Faculty Publications

In 1999, an interdisciplinary research team at the University of Nebraska established a field experiment to (1) quantify and understand the yield potential of corn and soybean under irrigated conditions, (2) identify efficient crop management practices to achieve yields that approach potential levels, and (3) determine the energy use efficiency, global warming and soil C-sequestration potential of intensively managed corn systems. The experiment compares systems that represent different levels of management intensity expressed as combinations of crop rotation (continuous corn, corn-soybean), plant density (low, medium, high) and nutrient management (recommended best management vs. intensive management). Detailed measurements include soil nutrient …

Crop Sequence And Nitrogen Fertilization Effects On Soil Properties In The Western Corn Belt, M. A. Liebig, Gary E. Varvel, John W. Doran, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Understanding long-term management effects on soil properties is necessary to determine the relative sustainability of cropping systems. Soil physical, chemical, and biological properties were measured in a long-term cropping system study in the Western Corn Belt. Properties were evaluated after 16 yr in four crop sequences [continuous corn (Zea mays L.) (CC), corn–soybean [Glycine max. (L.)] (C–SB), corn–oat (Avena sativa L.) + clover (80% sweet clover [Melilotus officinalis L.] and 20% red clover [Trifolium pratense L.])–grain sorghum [(Sorghum bicolor (L.) Moench)–soybean (C–OCL–SG– SB), and corn–soybean-grain sorghum–oat + clover (C–SB–SG– OCL)] each at three …

Soil Organic Matter Assessments In A Long-Term Cropping System Study, Gary E. Varvel, Mark A. Liebig, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Assessing effects of cropping systems on soil organic matter (SOM) and soil carbon (C) changes are necessary to make accurate projections regarding sequestration and emission of CO₂ by agricultural soils. This process requires substantial annual management inputs and large outlays for soil sampling and analyses. Our objectives were (1) to evaluate and test an alternative method for soil organic matter determination, (2) to determine if crop rotation and N fertilizer management significantly affected soil organic matter at the beginning (1986) or after 12 yrs (1998), and (3) to determine if total soil organic matter levels have changed after 12 …

Critical Period For Weed Control: The Concept And Data Analysis, Stevan Z. Knezevic, Sean P. Evans, Erin E. Blankenship, Rene C. Van Acker, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

The critical period for weed control (CPWC) is a period in the crop growth cycle during which weeds must be controlled to prevent yield losses. Knowing the CPWC is useful in making decisions on the need for and timing of weed control and in achieving efficient herbicide use from both biological and economic perspectives. An increase in the use of herbicide-tolerant crops, especially soybean resistant to glyphosate, has stimulated interest in the concept of CPWC. Recently, several studies examined this concept in glyphosate-resistant corn and soybean across the midwestern United States. However, these studies presented various methods for data analysis …

Growth Response Of Velvetleaf To Three Postemergence Herbicides, Cheryl A. Murphy, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Knowledge of how reduction in the rate of herbicide application or rotation of their mode of action influences weed growth will provide insight into how successful these practices will be in an integrated weed management program. Field experiments were conducted in 1996 and 1997 to quantify velvetleaf growth response to three postemergence herbicides, each with a different mode of action. A monoculture of velvetleaf was treated with halosulfuron, dicamba, and flumiclorac at 0, 0.10, 0.25, 0.50, 0.75, and 1.0 X the labeled rate for weed control in corn. Percent plant mortality increased with rate of application; the greatest mortality occurred …

Combinatorial Control Of Yeast Fet4 Gene Expression By Iron, Zinc, And Oxygen, Brian M. Waters, David J. Eide

Department of Agronomy and Horticulture: Faculty Publications

Acquisition of metals such as iron, copper, and zinc by the yeast Saccharomyces cerevisiae is tightly regulated. High affinity uptake systems are induced under metal-limiting conditions to maintain an adequate supply of these essential nutrients. Low affinity uptake systems function when their substrates are in greater supply. The FET₄ gene encodes a low affinity iron and copper uptake transporter. FET₄ expression is regulated by several environmental factors. In this report, we describe the molecular mechanisms underlying this regulation. First, we found that FET₄ expression is induced in iron-limited cells by the Aft1 iron-responsive transcriptional activator. Second, FET …

Genetic Analysis Of Feed Quality And Seed Weight Of Sorghum Inbred Lines And Hybrids Using Analytical Methods And Nirs, C. Hicks, M. R. Tuinstra, Jeffrey F. Pedersen, F. E. Dowell, K. D. Kofoid

Department of Agronomy and Horticulture: Faculty Publications

Eight lines of grain sorghum and their F1 hybrids were evaluated for contents of crude protein (CP), fat (FAT), and starch (STA); protein digestibility (PD); and in vitro dry matter disappearance (IVDMD). The effect of seed weight (SW) on these traits and the potential use of near infrared reflectance spectroscopy (NIRS) to predict them also were investigated. The male lines included three normal-seeded lines (TX2737, TX435, and P954063) and two largeseeded lines (PL-1 and Eastin1). The female lines included commonU.S. seed parent lines (Wheatland, Redlan, and SA3042). The lines and their hybrids were grown under dryland conditions at Kansas State …