Biological Engineering Commons^™

Development Of Deficit Irrigation Strategies For Corn Using A Yield Ratio Model, Derek M. Heeren, Todd P. Trooien, Hal D. Werner, Norman L. Klocke

Biological Systems Engineering: Papers and Publications

Competition for water is increasing while a growing world population requires more food production. It is critical to develop and implement efficient deficit irrigation strategies and to predict the impacts of deficit irrigation on yield. South Dakota State University (SDSU) Management Software, which simulates evapotranspiration and soil water contents, was originally designed as an on-farm decision support system capable of fully automating center pivot irrigation. A simple yield model was developed for the software in order to extend its use for evaluating deficit irrigation strategies. Yield ratio (i.e., actual yield/potential yield) was predicted based on a normalized transpiration ratio (i.e., …

Corn Seed Spacing Uniformity As Affected By Seed Tube Condition, Michael F. Kocher, John M. Coleman, John A. Smith, Stephen D. Kachman

Biological Systems Engineering: Papers and Publications

Variation in corn seed spacing from a John Deere MaxEmerge^TM Plus Vacumeter planter was evaluated on the University of Nebraska Planter Test Stand in a laboratory setting for two seed tube conditions (new or worn) with two examples of corn seed shape (round or flat). Seed spacing uniformity was measured using three seed spacing uniformity parameters: Coefficient of Precision (CP3), ISO Multiples index, and ISO Miss index.

Differences were detected in all three seed spacing uniformity parameters due to the seed tube condition. The new seed tubes had better seed spacing uniformity than the worn seed tubes, within each …

Plant Sterol And Policosanol Characterization Of Hexane Extracts From Grain Sorghum, Corn, And Their Ddgs, Caolina Leguizamón, Curtis L. Weller, Vicki L. Schlegel, Timothy P. Carr

Biological Systems Engineering: Papers and Publications

Plant sterols (PS) and policosanols (PC) have been attributed with plasma cholesterol-lowering properties in humans. Hexane extracts from grain sorghum, corn and their distillers dried grain with solubles (DDGS), an important co-product of ethanol production, contain these health promoting compounds, which could be used to develop health promoting dietary products. However, limited information is currently available regarding optimal methods of extraction and their influence on plant sterol or PC levels and compositions. Therefore, the objective of this study was to quantify lipids, particularly PS and PC extracted from grain sorghum and its DDGS using reflux and Soxtec methods. Corn and …

Field Slope Effects On Uniformity Of Corn Seed Spacing For Three Precision Planter Metering Systems, Corey L. Searle, Michael F. Kocher, John A. Smith, Erin E. Blankenship

Biological Systems Engineering: Papers and Publications

The effects of field slope on planter seed spacing uniformity were evaluated for three different seed metering units (cell plate, finger pick‐up, and flat plate) operating with medium round corn seed in a laboratory using the University of Nebraska planter test stand with an opto‐electronic seed spacing sensor system. The metering units included a John Deere MaxEmerge™ Plus VacuMeter row unit with the standard cell corn plate, a John Deere MaxEmerge™ Plus VacuMeter row unit with the flat plate, and a John Deere MaxEmerge™ Plus row unit with the finger pick‐up metering system. Planter seed spacing uniformity was measured using …

Leaching And Sorption Of Nitrogen And Phosphorus By Crop Residue, J. D. Cermak, John E. Gilley, Bahman Eghball, B. J. Weinhold

Biological Systems Engineering: Papers and Publications

Overland flow from cropland areas often contains nutrients and residue materials can either contribute to runoff nutrient load through leaching or remove nutrients by sorption. Measurements were made of leaching and sorption of nitrogen and phosphorus from corn (Zea mays L.), soybean (Glycine max (L.) Merr.) and winter wheat (Triticum aestivum L. cv. Pastiche) residues placed in solutions containing inorganic nutrients. Variables used were type of residue material, nutrient constituent, solution concentration, and residue / solution contact time. For a given residue material and nutrient constituent, four different solution concentrations were used (PO₄ -P: 0 to …

Drying Rate Constants For Yellow Dent Corn As Affected By Fatty Acid Ester Treatments, Curtis L. Weller, J. M. Bunn

Biological Systems Engineering: Papers and Publications

Ethyl oleate and ethyl stearate solutions at various concentrations were used to treat corn samples prior to drying.

Mechanical And Barrier Properties Of Edible Corn And Wheat Protein Films, T. P. Aydt, Curtis Weller, R. F. Testin

Biological Systems Engineering: Papers and Publications

Published methods for production of homogeneous edible films from com and wheat proteins were adapted. Barrier and mechanical properties of the edible films were evaluated with procedures commonly used on polymeric films. Mechanical property data included thickness, elongation, tensile strength, tear strength, and burst strength measurements. Barrier property data included water vapor, oxygen, and carbon dioxide gas transmission rate measurements. Homogeneous com and wheat protein films were found to have low tensile strengths, far less than cellophane. Com films were brittle while wheat films were elastic in comparison to cellophane. All three types of film had low permeabilities for dry …