bluuebunny/crossref_metadata_2025_split huggingface dataset:
Starter Fertilizer and Planting Date Effects on Corn Rotated with Cotton
Authors: Mascagni Henry J. , Boquet Donald J. 
Published: July 2010

AbstractCorn (Zea mays L.) has become an important crop used in rotation with cotton (Gossypium hirsutum L.) in the mid‐South region of the USA, but there has been little research on cultural practices for corn in this cropping system. The objective of this study was to determine if starter fertilizer has beneficial effects on corn growth and grain yield at different planting dates. Starter fertilizer and planting date effects were evaluated for corn in field experiments on a Commerce silt loam (fine‐silty, mixed, nonacid, thermic Aeric Fluvaquent) for 3 yr (1991 through 1993). Six hybrids were evaluated with two starter fertilizer treatments at four planting dates. Starter treatments were (i) ammonium polyphosphate (11‐37‐0 N‐P‐K) applied in‐furrow and (ii) a control with no starter fertilizer. Planting dates were mid‐March, early April, mid‐April and late April or early May. Yield response to planting date was not consistent across years; in two of three years, however, planting later than early April decreased yield. The starter fertilizer increased grain yield in two of the three years. Yield response to starter fertilizer was not consistent across years, hybrids, or planting dates. The planting date × starter interaction for yield was significant in two of three years and the hybrid × starter interaction for yield was significant in one of three years. Starter fertilizer increased early‐season plant height by 2 to 36% and increased grain yield across planting dates from 0.5 to 1.4 Mg ha−1 in 1991 and 0.4 to 1.0 Mg ha−1 in 1993. There was no yield response to starter in 1992. Application of starter fertilizer, averaged across hybrids and years, reduced harvest grain moisture 5% and days to silking by 3 to 5 d. In this mid‐South study, in‐furrow N‐P starter fertilizer increased early‐season corn plant height and grain yield and decreased the number of days to silking of corn rotated with cotton.
Genotypic Interactions with Potassium and Nitrogen in Cotton of Varied Maturity
Authors: Pettigrew William T. , Heitholt James J. , Meredith William R. 
Published: July 2010

AbstractThe development of late‐season K deficiency symptoms in cotton (Gossypium hirsutum L.) fields has become more frequent in the Mid‐South and Far West U.S. production regions. In this study, the objectives were to determine how yield and quality of lint produced by cotton genotypes of varying maturities are affected by different rates of soil applied K and N fertilization. Eight cotton genotypes representing a range of maturities and regional adaptations were studied in Mississippi in 1991 and 1992. All plots received a preplan! application of 112 kg ha−1 N and half the plots also received a 38 kg ha−1 sidedress application of N. Within each N treatment, half the plots received 112 kg ha−1 K surface applied and preplant incorporated, with the remaining plots receiving 0 kg ha−1 K. Averaged across years and N treatments, the K deficiency associated with the 0 K treatment reduced lint yield (9%), boll mass (7%), lint percentage (1%), and seed mass (4%). Varying the N fertilization did not benefit these parameters. The high N treatment reduced lint yield 3% (P = 0.07) and lint percentage 1% (P = 0.06) when coupled with the 0 K treatment. All genotypes suffered yield reductions caused by the K deficiency, except for ‘HS 26’, which was not adapted for production in the Mississippi Delta. Potassium deficiency produced reductions in fiber elongation (3%), 50% span length (1%), uniformity ratio (1%), micronaire (10%), fiber maturity (5%), and perimeter (1%) in all genotypes. Nitrogen application above the 112 kg ha− rate did not increase the lint yield under the growing conditions of our study. The data indicate that genotype was not of importance when dealing with K fertility. The deficiency itself, however, must be dealt with to avoid significant reductions in the yield and quality of fiber produced.
Modeling Preemergent Maize Shoot Growth: II. High Temperature Stress Conditions
Authors: Weaich Karl , Bristow Keith L. , Cass Alfred 
Published: July 2010

AbstractHigh soil temperatures are a significant constraint to crop establishment. Exposure of preemergent maize (Zea mays L.) to temperatures in excess of 40°C stops shoot elongation and may also damage the seedling, reducing subsequent shoot growth in the physiological temperature range (9 to 40°C). At present, there is little quantitative understanding of the effects of high temperature stress on preemergent maize shoot growth. Consequently, existing maize emergence or preemergent maize shoot growth models are restricted to the physiological temperature range. The work described in this paper quantified the effect of supramaximum temperatures (temperatures greater than 40°C) on maize shoot growth, and in particular on its component parts, the coleoptile and first internode. The major impact of supramaximum temperatures on shoot growth was due to a severe reduction in the first internode growth rate, which was correlated with the maximum temperature reached during the day. We also found that, under diurnally varying temperature conditions, coleoptile growth ceased only at 45°C, rather than at 40°C as found previously in constant temperature experiments. Inhibition of shoot growth due to high temperature damage was alleviated when seedlings were grown in the physiological temperature range for 33 h. Based on these findings, a model was developed that can predict shoot growth of seedlings exposed to supramaximum temperatures. The model successfully predicted shoot growth of seedlings exposed to supramaximum temperatures as a part of the diurnal cycle. The model was unable, however, to predict seedling recovery from high temperature damage.
Simulating Alamo Switchgrass with the ALMANAC Model
Authors: Kiniry James R. , Sanderson Matt A. , Williams Jimmy R. , Tischler Charles R. , Hussey Mark A. , Ocumpaugh William R. , Read James C. , Van Esbroeck George , Reed Roderick L. 
Published: July 2010

AbstractA model for forage yield with adequate details for leaf area, biomass, nutrients, and hydrology would be valuable for making management decisions. The objectives of this study were to develop Alamo switchgrass (Panicum virgatum L.) parameters for the Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model and demonstrate its accuracy across a wide range of environments. Derived plant parameters included potential leaf area index (LAI), potential biomass growth per unit intercepted light, optimum nutrient concentrations, and growth responses to temperature. The model's simulated yields accounted for 79% of the variability in measured yields for one‐cut and two‐cut harvest systems from six diverse sites in Texas in 1993 and 1994. Simulated yields for three locations differed in sensitivity to potential LAI, heat units to maturity, radiation use efficiency (RUE), and soil depth. The ALMANAC model shows promise as a management tool for this important forage and bioenergy crop.
Measuring Soil Water Content in the Laboratory and Field with Dual‐Probe Heat‐Capacity Sensors
Authors: Tarara Julie M. , Ham Jay M. 
Published: July 2010

AbstractDual‐probe heat‐capacity sensors were constructed and tested in laboratory and field conditions to determine their application for measuring volumetric soil water content (θv). The dual‐probe technique uses a transient heat pulse and a temperature sensor to determine the volumetric heat capacity of the soil (pcp), which can be subsequently converted to θv for a nonswelling soil if bulk density is known. In 1994, 24 dual‐probes were simultaneously tested using a multiplexed data acquisition system. In the laboratory, probes were calibrated to the known heat capacity of water. Following calibration, the probes correctly estimated pcp of glass beads and water‐saturated glass beads to within 2.2 and 0.2% of their calculated values, respectively. Gravimetric and dual‐probe estimates of θv were compared using the Tempe pressure cell technique to desorb soil columns. The two methods agreed to within 0.03 m3 m−3 and 0.04 m3 m−3 in two soil types, over a range of θv from 0.45 m3 m−3 to 0.10 m3 m−3; estimates of the change in θv (Δθv) between desorption steps agreed to within 0.01 m3 m−3. In the field, beneath bare soil, estimates of θv among three dual‐probes installed at the same depth agreed, on average, to within 0.02 m3 m−3. The probes detected Δθv within 30 min during the 21‐d field trial. Dual‐probe and gamma‐attenuation measurements of θv agreed to within 0.05 m3 m−3. In 1995, probe design was improved to produce more robust, reliable instruments. Sixteen probes were installed 10 cm beneath a drip‐irrigated row crop. A consistent difference in θv of ≈0.10 m3 m−3 between mulch‐covered and bare soil beds was detected during the 25‐d trial. The dual‐probe heat‐pulse technique for measuring θv has direct applicability in agronomic and horticultural production, where small‐scale, automated measurements of θv are needed.
Yield Accumulation in Irrigated Sugarcane: II. Utilization of Intercepted Radiation
Authors: Muchow Russell C. , Evensen Carl I. , Osgood Robert V. , Robertson Michael J. 
Published: July 2010

AbstractIntercepted radiation is a major driving variable of crop production under high‐input irrigated conditions. Quantitative information on the utilization of radiation in yield accumulation allows extrapolation beyond the current season and location, and when this information is incorporated into crop growth simulation models, the effect of crop age on the productivity of different cultivars can be examined under different climatic conditions. This paper examines the differential performance of high‐yielding sugarcane (Saccharum spp. hybrids) crops in terms of the amount of short‐wave solar radiation intercepted (Si) and the efficiency of use of intercepted radiation (RUE) in biomass production. Biomass accumulation during the 12‐ to 24‐mo crop cycle was examined for two experiments conducted in Hawaii, and three experiments conducted in tropical Australia from 1991 to 1993. The analysis showed that (i) RUE was much less for growth after 12 mo than in the first 12 mo; (ii) maximum RUE of sugarcane approaches 2.0 g MJ−1; (iii) biomass accumulation beyond 12 mo was not related directly to radiation utilization; and (iv) cultivars differed in S19 but differences in RUE could not be unequivocally assessed due to the confounding effect of variable recovery of trash in biomass estimates. It is concluded that stalk death and consequent biomass loss are important factors contributing to yield variation in sugarcane crops growing for 12 to 24 mo, with a yield plateau occurring at variable crop ages during the second year of growth.
AEGIS/WIN: A Computer Program for the Application of Crop Simulation Models Across Geographic Areas
Authors: Engel Thomas , Hoogenboom Gerrit , Jones James W. , Wilkens Paul W. 
Published: July 2010

AbstractComputer‐based biological simulation models have been used to calculate the effects of different management practices and land‐use systems on agricultural production and to assess the impact of these practices on the environment. Using spatial visualization techniques to display simulation results can significantly improve the presentation and interpretation of these analyses. The objective of this study was to develop a computer program for the spatial application of crop models as well as the analysis and visualization of modeled results. The Agricultural and Environmental Geographic Information System for Windows (AEGIS/WIN) links the simulation system Decision Support System for Agrotechnology Transfer (DSSAT) v3 with the geographic mapping tool ArcView 2. The interface between the two systems was programmed using Avenue, an object‐oriented macro programming language. This interface handles automatic data and command transfers between the simulation system and the mapping tool and does not require any modifications of DSSAT v3. The main spatial input for AEGIS/WIN is a coverage in the form of a digital map of a farm, a region, or any other area. DSSAT is used to create model input files and to execute the various crop management scenarios for the selected coverage. The crop model outputs can be imported and joined with the original selected land‐use map in ArcView. The simulation results can be analyzed with AEGIS/WIN using simple statistics and bar charts. AEGIS/WIN's most important feature is the display of thematic maps of simulated crop yield, yield components, and other related agronomic and environmental variables. The system was applied to study the spatial yield variability of peanut (Arachis hypogaea L.) for a research farm in Georgia. AEGIS/WIN was shown to be an effective tool for the spatial application of crop simulation models and for the analysis and visualization of simulated outputs.
Dollar Spot Severity as Influenced by Trinexapac‐ethyl, Creeping Bentgrass Cultivar, and Nitrogen Fertility
Authors: Golembiewski Robert C. , Danneberger T. Karl 
Published: July 2010

AbstractDollar spot (Sclerotinia homoeocarpa F.T. Bennett) is a widely distributed and destructive pathogen of turfgrass in the United States. A 2‐yr field study was conducted at Columbus, OH, to determine the influence of a plant growth regulator, creeping bentgrass (Agrostis stolonifera L.) cultivars, and N fertility on dollar spot severity. ‘Crenshaw’ creeping bentgrass was seeded alone or in a 50:50 blend by weight with ‘Penncross’ creeping bentgrass. Plots were fertilized at 0, 24.4, or 48.8 kg N ha−1 per application. One‐half of each plot received trinexapac‐ethyl (TE) [4‐(cyclopropyl‐α‐hydroxymethylene)‐3,5‐dioxo‐cyclohexanecarboxylic acid methyl ester] at 0.8 L ha−1. The TE and fertilizer treatments were initiated in May 1995 and 1996 with four subsequent applications made at 30‐d intervals. Initially, the cultivar blend reduced the rate of dollar spot development compared with Crenshaw alone; however, neither the blend nor Crenshaw provided commercially acceptable dollar spot suppression throughout the study. Both TE and N fertilization significantly (P ≤ 0.05) reduced dollar spot severity over the 2‐yr period. Trinexapacethyl applied alone effectively suppressed dollar spot activity, but efficacy increased with increasing N rates. Dollar spot symptoms decreased and thatch thickness increased at elevated N levels. During this 2‐yr study, interactions between TE and N fertility resulted in a significant (P ≤ 0.05) reduction in dollar spot severity. Thus, on golf course fairways where dollar spot may be severe, incorporation of these two treatments into a turfgrass management program will enhance dollar spot suppression and reduce fungicide inputs.
Seed Maturity in Four Cool‐Season Forage Grasses
Authors: Berdahl John D. , Frank Albert B. 
Published: July 2010

AbstractExcessive seed shattering of perennial grasses in the Triticeae tribe results in major economic losses to seed producers. In this 4‐yr field study, heat units expressed as growing degree‐days (GDD) after anthesis were related to seed development in tetraploid crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schultes], Russian wildrye [Psathyrostachys juncea (Fisch.) Nevski], intermediate wheatgrass [Thinopyrum intermedium (Host) Barkw. & D.R. Dewey], and western wheatgrass [Pascopyrum smithii (Rydb.) A. Löve]. Seed quality at different stages of development was assessed by germination percentage and emergence of seedlings from a 5.0‐cm planting depth in a Parshall fine sandy loam soil (coarse‐loamy, mixed Pachic Haploborolls). Water concentration of the seed at maximum seed mass (dry wt. basis) ranged from 303 g kg−1 for intermediate wheatgrass to 376 g kg−1 for western wheatgrass. Seed mass was closely associated with seed vigor in all four grass species, as evidenced by correlation coefficients between seed mass and seedling emergence of 0.88** for crested wheatgrass, 0.93** for Russian wildrye, 0.92** for intermediate wheatgrass, and 0.77** for western wheatgrass. Plots sampled at the stiff‐dough stage had a water concentration of approximately 350 g kg−1 (dry wt. basis), and the seed sample was at or near maximum seed mass. Seed mass and germination would not be seriously compromised and seed yield losses from shattering would be reduced if windrowing were completed about 50 GDD or 2 to 3 calendar days before maximum seed mass is attained.
Entry ✕ Environment Interactions for Alfalfa Forage Quality
Authors: Sheaffer Craig C. , Cash Dennis , Ehlke Nancy J. , Henning Jimmy C. , Jewett Jane Grimsbo , Johnson Keith D. , Peterson Michael A. , Smith Mark , Hansen Julie L. , Viands Donald R. 
Published: July 2010

AbstractAlfalfa (Medicago sativa L.) cultivars are available that produce high‐quality forage; however, information is lacking on the consistency of cultivar forage quality over environments and the influence of stand age on quality. Our objectives were to evaluate alfalfa cultivars for consistency of forage quality over time and environments and to test the validity of sampling seeding‐year stands for forage quality. We sampled eight alfalfa entries (seven cultivars and one experimental germplasm) at bud and flower maturity stages in the seeding year (one harvest) and first production year (two harvests) in six states (Indiana, Kentucky, Minnesota, New York, Washington, and Wisconsin). ANOVA and orthogonal contrast analyses were conducted to assess entry × environment interactions for forage quality. First‐cut forage in the first production year had lower forage quality than third‐cut forage, and differences between entries were more pronounced at the first cutting. Including seeding‐year data in the ANOVA produced a complex location × entry × stand age interaction, indicating that seeding‐year data alone were insufficient to characterize alfalfa entries for forage quality. ‘Cimarron VR’, ‘Arrow’, and ‘5432’ had the greatest stability for forage quality and could serve as high, medium, and low forage‐quality checks, respectively, in forage quality testing trials. ‘WL 322 HQ’ and ‘Pacesetter’ often had high quality, but were not stable for forage quality over environments. Correlations between crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), and in vitro digestible dry matter were consistent across locations, entries, cuttings, and maturities. The high correlation between NDF and ADF (r > 0.97, P < 0.05) suggests that it may not be necessary to use both procedures to predict entry differences in forage quality.
Phosphorus and Potassium Placement Effects on Early Growth and Nutrient Uptake of No‐Till Corn and Relationships with Grain Yield
Authors: Mallarino Antonio P. , Bordoli José M. , Borges Rogerio 
Published: July 2010

AbstractEarly plant growth and grain yield of no‐till corn (Zea mays L.) are usually lower than for conventionally tilled corn in the northern U.S. Corn Belt. Root‐zone fertilization is likely to enhance early growth and increase yields. This study evaluated the effects of P and K placement on early growth and P and K uptake of no‐till corn, and on relationships between these effects and grain yield response to placement. Ten long‐term P and K trials (5 trials each, P and K) were established in 1994 at five research centers and were evaluated for 3 yr; 11 1‐yr P‐K trials were established in farmers' fields (1994–1996). Treatments several P and K rates (0–56 kg P ha−1; 0–132 kg K ha−1) banded with the planter 5 cm beside and below the seeds and broadcast or deep‐banded at a 13‐ to 18‐cm depth before planting. Soil samples were collected before applying the treatments from the 0‐ to 7.5‐cm and 7.5‐ to 15‐cm depths. Soil‐test P (0‐15 cm) ranged from very low to very high across sites and soil‐test K ranged from optimum to very high. Banded P (deep or shallow) increased early growth and P uptake more than the broadcast placement did at most trials. Phosphorus increased yields only in very low and low testing soils, and there was no response to P placement. Banded K (deep or shallow) seldom affected early growth, but usually increased K uptake. Potassium increased yields in several soils that tested optimum or higher in soiltest K, and yields were higher when K was deep banded. Planting onto a fall‐applied coulter‐knife track without applying P or K often increased early growth and nutrient uptake, but seldom increased yields. Early growth and nutrient uptake responses to banded P did not translate into higher yields. Small but frequent yield responses to deep‐banded K were not related to increased early growth, but could be partly explained by increased K uptake. Judging potential effects of P and K placement on grain yields of no‐till corn based on effects (or lack of effect) on early growth may be misleading for soils that are not extremely deficient in these nutrients.
Banded Wetting Agent and Compaction Improve Barley Production on a Water‐Repellent Sand
Authors: Crabtree William L. , Gilkes Robert J. 
Published: July 2010

AbstractLarge areas of cropland in Western Australia exhibit severe annual water repellency. Crop establishment is frustrated by the staggered emergence of plants, despite significant amounts of rain falling prior to the desired time of seeding. Three techniques were used to investigate improvements in barley (Hordeum vulgare L.) establishment on a water‐repellent sand: (i) spraying various rates of banded (2 cm wide) wetting agent while furrow seeding with press wheels, (ii) seed placement either in a furrow or in the side of a ridge, and (iii) compaction with press wheels or a Flexi‐Coil land packer. The application of wetting agent increased seedling emergence from 110 to 170 plants m−2, dry matter production from 4.2 to 6.01 t ha−1 and grain yield from 1.96 to 2.60 t ha−1, despite more weeds occurring with increasing rate of banded wetting agent. Use of press wheels, which also resulted in a furrow sowing condition, increased seedling emergence from 72 to 101 plants m−2 and grain yield from 1.70 to 2.13 t ha−1. In the absence of heavy press wheel compaction, furrow sowing at 18‐cm row spacings with full soil disturbance had no effect on seedling emergence or grain yield. The application of wetting agent increased topsoil wetting. Increased soil wetting may have increased plant nutrient availability (from fertilizer and soil), reduced soil water evaporation, and possibly reduced water loss to subsoil on this duplex soil. The optimum degree of compaction required on water‐repellent soils is not known and needs further research.
The Dissolution of Synthetic Goethites: The Early Stage
Authors: Cornell R. M. , Posner A. M. , Quirk J. P. 
Published: July 2010

AbstractThe kinetic curve for the early stage of dissolution of synthetic goethite is linear except for a small curved region close to the origin. This curved region has been shown to be due to the very rapid dissolution of a small amount of amorphous ferric hydroxide which is associated with the goethite.The amount of amorphous ferric hydroxide is usually no more than 0.2% of the total mass of goethite. Its presence cannot be detected even by electron diffraction methods.