bluuebunny/crossref_metadata_2025_split huggingface dataset:
Portland Cement as a Soil Amendent for Corn and Soybeans1
Authors: Stivers R. K. , Swartzendruber D. , Nyquist W. E. 
Published: July 2010

AbstractIn the corn belt there are many areas of imperfectly drained soils, often adjacent to well‐drained soils in the same fields. Tile drainage of these imperfectly drained soils helps remove excess water within the profile. Slow movement of water into and through the Ap horizon of these soils is thought to contribute to reduced crop yields in wet years. Since application of Portland cement (the binding material in concrete) to soil in a laboratory experiment increased water‐stable soil aggregate size as well as hydraulic conductivity of a soil, it was assumed that cement would act similarly in the field and increased crop yields, particularly under wet conditions.Two experiments were conducted to determine whether the application of portland cement (the binding material in concrete) would increase crop yields or change selected chemical and physical properties of soil. The first experiment was on two silt loam soils—a fine silty, mixed mesic Typic Hapludalf (Russell) and a fine silty mixed mesic Aquiac Arqiudall (Raub) in 1970. Cement was incorporated at 0, 560, 1,120, 2,240, and 4,480 kg/ha in a randomized complete block design with four replications per soil. At the end of the 1970 cropping year each plot was split, and the same rates were again applied on one of the two subunits. Corn (Zea mays L.) was grown in 1970 and 1971, and soybeans (Glycine max L. Merr.) in 1972 and 1973. The second experiment was on two other silt loam soils, a fine illitic mesic Typic Hapludalf (Morley) and a fine illitic mesic, Aerie Ochraqualf (Blount), at a different location. Cement was incorporated in 1971, at 0, 3,920, and 19,600 kg/ ha, each rate with 0 and 122 kg/ha of P, with three replications per soil. Corn was grown in 1971 and 1972, and soybeans in 1973. Corn yield increased H.9%, mean weight diameter (MWD) of water‐stable soil aggregates increased 54.5%, and soil pH increased 24.6%, with the 19,600 kg/ha rate on Blount soil in 1971. Multiple regression analyses for that soil showed an influence of cement on corn yield not accounted for by MWD and/ or pH, either singly or together. There were no other crop‐yield increases related to cement application, but there were increases in Ca and decreases in z concentration in corn or soybean leaves in selected years. In summary, crop yield increases occurred in one out of six applications of cement and were not economical when they did occur.
Uptake and Losses of 15N Applied to Annual Grass and Clover in Lysimeters1
Authors: Jones M. B. , Delwiche C. C. , Williams W. A. 
Published: July 2010

AbstractThe California annual grasslands comprise about one‐third of the state, and they play a large role in the hydrology of most watersheds in central and northern California. Apparent recovery of applied N has been low, and a large percentage has been unaccounted for in N balance studies. The present experiment was done with 15N to determine the fate of applied N, especially that leached and that volatilized (by difference).Ammonium sulfate labeled with 15N ammonium chloride was applied to pure stands of soft chess (Bromus mollis L.) and subclover (Trilolium subterraneum L.) growing in lysimeters in a climate with mild, rainy winters and hot, dry summers. Uptake and leaching of N were measured on single and repeated applications for 3 years (mean annual rainfall 1,100 mm). After 3 years of annual fertilization in February (100 kg N/ha) 59% of N applied to grass was removed in forage, 24% remained in the soil and roots, 3% leached, and 14% was not detected (presumed gaseous loss); for clover 49% was removed in the forage, 33% remained in the soil and roots, 9% leached, and 9% was not accounted for. October fertilization at the same rate produced in both species about the same total growth, markedly decreased plant uptake, increased soil‐plus‐root retention, increased leaching, and reduced unaccounted for N from fertilizer. An October application of 500 kg N/ha resulted in greater gaseous losses of N, and more was lost from clover than grass.Conclusions: There was modest leaching loss but essentially no gaseous loss from moderate rates of N applied to grass in October; there was almost negligible leaching loss but modest gaseous loss from moderate rates of N applied to grass in February; recovery of fertilizer by clover was poor; and a single large application (500 kg N/ha) resulted in a substantial leaching and gaseous losses under both grass and clover.
Use of Hardwood Bark Mulch for Highway Slope Stabilization1
Authors: Osborne D. J. , Gilbert W. B. 
Published: July 2010

AbstractMany studies have indicated the utility of mulching of bare roadbanks to enhance cover production and reduce runoff and erosion. The objective of this study was to determine the suitability of shredded hardwood bark as a replacement for the conventional straw‐asphalt mulch. Bark mulch was used for seeding tall fescue (Festuca arundinacea L.) during “off season” summer months; in addition, plots were mulched with bark in the summer and left unseeded until fall when they were hydroseeded with tall fescue and fertilizer. Field plot tests were conducted in each physiographic province of the state on Porters loam (fine‐loamy, mixed, mesic Humic Hapludults), Cecil and Mayodan sandy loam (clayey, kaolinitic, thermic Typic Hapludults), and Norfolk sandy loam (fine‐loamy, siliceous, thermic Typic Paleudults). Plots were prepared with conventional tillage equipment to meet state specifications. Shredded hardwood bark mulch was applied with a modified mulch blower at 66 m3/ha. Stand density of tall fescue tillers per square decimeter was evaluated by quadrat counts. Results indicate that in general, the more favorable the environment for tall fescue production, the better the stand density with any one treatment. Under cool temperature and frequent rainfall, no differences were noted. These experiments demonstrated that highway slopes may be mulched with shredded hardwood bark and left unseeded until optimum fall seeding date with adequate erosion control, obviating the need for recultivation currently used to establish permanent cover after a “temporary seeding” during the summer.
Residual Effects of N Fertilization on Dryland Spring Wheat in the Northern Plains. II. Fate of Fertilizer N1
Authors: Alessi J. , Power J. F. 
Published: July 2010

AbstractResidual effects of fertilizer application on the fate of fertilizer N applied to crops in semiarid regions are largely unknown. Objectives of this study were to provide information on the recovery of fertilizer N during the fertilization and residual periods and to develop an N balance sheet for a continuous spring wheat (Triticum aestivum L.) cropping system.Ammonium nitrate was applied to spring wheat at 0 to 540 kg N/ha rate either (i) all in 1 year, (ii) one‐third in each of 3 years, or (iii) one‐sixth in each of 6 years to evaluate the availability and fate of fertilizer N in a dryland cropping system. Only grain was removed during harvest, and straw was plowed under each spring. Grain N uptake accounted for 31 to 46% of the total fertilizer N applied at 270 and 540 kg N/ha rate for various timing frequency. Fertilizer N uptake in straw and root biomass at the end of the experiment averaged 5 and 26 kg/ha, respectively. Movement of NO3‐N below the 90‐ cm depth (leaching) was detected for the 270 kg N/ha treatment, whether this total amount was applied all in 1 year, or 90 kg N/ha was applied in each for 3 years. However, with an annual application of 45 kg N/ha for 6 continuous years very little leaching of NO3‐N occurred. The amount of fertilizer N that moved beyond the root zone was greater at 540 than at 270 kg N/ha. Leaching of fertilizer N below 90 cm accounted for 4 to 37% of the total fertilizer applied, with greatest leaching occurring For the 1‐year treatment and least for the 6‐year treatment. Loss of N by runoff was negligible. The percent fertilizer N accounted for [(total fertilizer accountable ÷ total fertilizer applied) × 100] averaged 62, 64, and 66 for 1, 3, and 6‐year treatments, respectively. Unaccounted for fertilizer N possibly consisted of that portion of fertilizer N immobilized in soil organic fractions resistant to decomposition and that lost by volatilization. Results showed that if the N rate is adequate for maximum crop production, fertilizer efficiency is greatest when N is applied annually rather than at higher rates less frequently.
Comparative Toxicity of Nitrapyrin and 6‐Chloropicolinic Acid to Radish and Cucumber under Different N Nutrition Regimes1
Authors: Sander Diane J. , Barker A. V. 
Published: July 2010

AbstractNitrapyrin, 2‐chloro‐6‐(trichloromethyl)pyridine, is a nitrification inhibitor used to maintain fertilizer N in the ammonium form in order to reduce leaching and denitrification losses of N from soil. Nitrapyrin and its metabolite, 6‐chloropicolinic acid, are phytotoxic, and ammonium injury to plants is frequently greater when nitrapyrin is added to the soil. The objectives of this study were to investigate the phytotoxicity of nitrapyrin and 6‐ chloropicolinic acid under different N nutrition regimes (15 meq/liter of NO3‐N. NH4‐N, or NH4‐N with pH buffering to 7 with CaCO3) and to see if either compound affected the phytotoxicity of ammonium ions. Radish (Raphanus sativus L. ‘Cherry Belle’), and cucumber (Cumumis sativus L. ‘SMR‐18’), were grown in sand culture in a greenhouse. Plant nutrients and the inhibitors (10 ppm) were supplied in solution, and CaCO3 was mixed with the sand. Radishes were uninjured by nitrapyrin or 6‐chloropicolinic acid. Ammonium‐N (15 meq NH4‐N/liter) nutrition produced toxicity symptoms in radish and decreased root yields. Buffering of pH partially corrected the ammonium toxicity to roots and fully corrected it for shoots. Nitrapyrin and 6‐chloropicolinic acid restricted cucumber growth. Visible symptoms of nitrapyrin toxicity appeared as constricted zones on the stem base and as white areas on petioles of first true leaves. Toxicity of 6‐chloropicolinic acid appeared as curling on younger leaves and marginal burn on older ones. Cucumber growth was restricted by ammonium‐N nutrition. Buffering of pH corrected the toxicity of ammonium‐N and picolinic acid but not that of nitrapyrin.
A Mechanized Washing System for Generating Soil‐Less Sod1
Authors: Turgeon A. J. , Berns Frank , Warren Ben 
Published: July 2010

AbstractWashed, soil‐less sod was developed to provide lightweight planting material that does not impose a foreign soil layer on the growing medium at the transplant site. The purpose of this study was to determine the feasibility of a mechanized sod washing technique. A sod‐washing apparatus consisting of motorized conveyors, high‐pressure water jets, rubber scrapers, and spring‐biased rollers is described. Strips of ‘A‐20’ Kentucky bluegrass (Poa protensis L.) and ‘Toronto’ creeping bentgrass (Agrostis palustris Huds.) sod were machine washed prior to measuring sod strength. The ‘Toronto’ sod began shredding apart after the first washing, but the ‘A‐20’ sod maintained adequate strength after four washings. The loss of sod strength in 'A‐20' from washing was attributed to the addition of moisture to the sod, and not to the removal of soil.
Check‐Wire System for Plot Planters1
Authors: Clark R. C. , Fehr W. R. , Freed J. C. 
Published: July 2010

AbstractA check‐wire system was developed to eliminate the need for marking the beginning and end of plots for planting. Use of the system can save several hours in planting a field. The system was designed for planters that are tripped by hand and is a modification of the system used with planters tripped electronically.Components of the system include a check‐wire and a commercial check‐head assembly. The check‐head, modified by adding a hammer and bell, can be mounted on the tractor or the planter. As the planter passes through the field, a bolt on the check‐wire trips a fork on the check‐head assembly. The hammer on the fork strikes the bell to signal the operator that the planter should be tripped to plant the next plot. Procedures for using the check‐wire system are described.
Manganese Availability of Calcareous Soils of Lebanon1
Authors: Khan M. I. A. , Ryan J. 
Published: July 2010

AbstractMajor agricultural areas of Lebanon were surveyed to determine Mn availability of soils and Mn content of crops grown on these soils. All soils sampled were calcareous and contained variable amounts of organic matter. Though a large number of crop species were sampled, no Mn deficiency symptoms were apparent, while Mn contents, which varied with the crop, were considered adequate by accepted criteria. A relatively small percentage of the soils extracted with NH4OAC, NH4H2PO4, and MgCl2 were considered deficient while none were deficient according to criteria for the DTPA extract. All availability indices showed Mn to increase with O.M. content but decrease with CaCO3 content. Availability was lowest in the drier Beka's Valley where O.M. was low and CaCO3 high. Inclusion of pH and CaCO3 in multiple regression analysis generally improved prediction of Mn uptake for all tests.
Utilization of Labelled Urea and Ammonium Sulfate by Lowland Rice1
Authors: Reddy K. R. , Patrick W. H. 
Published: July 2010

AbstractUrea and ammonium sulfate are the most common fertilizer N sources used to topdress rice (Oryza saliva L.). The high cost of N fertilizer and the possible environmental impact of excess N make it important to obtain good utilization of the fertilizer applied to the crop. The objective of the present investigation was to compare labelled ammonium sulfate and urea in their effect on yield and N utilization in field microplots on Crowley silt loam (typic albaqualf). Nitrogen was applied as an early season topdressing or as a midseason topdressing and the grain and straw yield and recovery of labelled and native N in the grain straw, and soil were measured.No significant differences in grain and straw yields were observed for the two sources and two times of N application. Ammonium sulfate and urea did not differ significantly in N utilization by the crop. For both sources the recovery of labelled N in the soil‐plant system was highest (34 to 55 kg N/ha) in the plots receiving midseason topdressing as compared to the plots receiving early season topdressing (30 to 38 kg N/ha). More native soil N was taken up by the plants during 1976 as compared to the 1975 season.
Selection for Drought Avoidance in Sorghum Using Aerial Infrared Photography1
Authors: Blum A. , Schertz K. F. , Toler R. W. , Welch R. I. , Rosenow D. T. , Johnson J. W. , Clark L. E. 
Published: July 2010

AbstractIn previous research, genetic variation in sorghum(Sorghum bicolor L. Moench) drought avoidance (maintenance of relatively high leaf water potential under conditions of soil moisture stress) was revealed. Practical screening for drought avoidance requires a fast field method. The response of near infrared reflectance from plant leaves to leaf water status stimulated the development of such a method, based on infrared photographic imagery of water‐stressed sorghum breeding nurseries.Aerial infrared photography was performed from several altitudes over water‐stressed and non‐stressed sorghum nurseries at Lubbock, Halfway, and Chillicothe, Texas. Noontime leaf water potentials, as a measure of drought avoidance, were determined in selected strains at each nursery. Total leaf chlorophyll content of the respective strains was determined at Lubbock and Chillicothe. Strain canopy color densities in the resulting infrared color transparencies were analyzed by three methods: l) Scanning densitometry; 2) measurement of integrated light transmittance by manual photometry; 3) visual rating of color density.Over all locations, the best correlations between canopy color density and leaf water potential across strains were obtained with the photometric method. The poorest correlations were obtained with scanning densitometry. For all methods of color density measurement, the correlations with leaf water potential across strains were the best at Halfway. At this location, plant canopies were dense, ground cover was almost complete, and film exposure and development were optimal. Leaf chloroFhyll content in the various strains was not correlated with canopy color density, although one strain presented a consistent exception. The method and some guidelines for its utilization are discussed.
Improved Technique for Marking and Sampling Band‐Applied Fertilizers and Pesticides1
Authors: Hendrickson L. L. , Keeney D. R. , Lesczynski D. B. , Walsh L. M. 
Published: July 2010

AbstractOne of the most difficult problems in field studies of the fate of band‐applied fertilizers and pesticides is obtaining a valid sample of the application zone. During the course of investigations to estimate the rate of nitrification and the recovery of N from banded fertilizers treated with a nitrification inhibitor, improved techniques for marking and sampling the band were developed. The band was marked by applying prilled elemental S at the point of fertilizer release. With this approach the band was easily detected many months after fertilizer application. The sampler was constructed of stainless steel and was 15 ✕ 15 ✕ 40 cm long. It was inserted into the soil above the previously located band and then removed and disassembled, and the soil subsectioned for a vertical profile of constituents in the band. The expanded dimensions of the sampler reduced sample variability, yet still allowed sufficient sampling efficiency to obtain adequate replication. These techniques provided more accurate estimates of nitrification and recovery of applied N and should find application in monitoring other fertilizers or pesticides on easily penetrated soils devoid of rocks.
Sugarbeet Genotype, N, and Soil Moisture Availability Interactions in Components of Beet Yield and Quality1
Authors: James D. W. , Doney D. L. , Theurer J. C. , Hurst R. L. 
Published: July 2010

AbstractThe effect of soil N on sugarbeet (Beta vulgaris L.) yield and quality has been studied extensively. However, comparatively few soil water (W) studies have been made on sugarbeet. Genotype (V) ✕ (N) interactions have been reported occasionally in one or a combination of the following parameters: root yield, sucrose percent, gross sugar, and impurity index. The interactions are very inconsistent from report to report. Most studies have involved a very narrow genetic base of two to three adapted sugarbeet hybrids.This study was conducted to investigate the genotype ✕ soil N and genotype ✕ soil water interaction from a broad genetic base. A series of 20 genetically different genotypes differing in yield, sugar percent, and impurity index potential were field tested in 1974 at four N levels: 0, 84, 210, and 525 kg/ha. In 1975, eight genetically diverse genotypes were field tested at five N levels and four irrigation levels. The soil type was a coarse, loamy mixed mesic family of calcic haploxerolls. Analysis of data were for root yield, sucrose percent, gross sugar, and impurity index. Highly significant main effects due to N in 1974 and 1975 and water in 1975 were observed for all measured parameters. A significant genotype (V) ✕ N (N) interaction was obtained in 1974 for all parameters. There was an apparent genotype ✕ water interaction in 1975; however, unbiased statistical inferences could not be made because of the experimental design. These interactions indicate that genetic variation exists such that new cultivars may be developed that give high sugar production at low N levels or are not affected adversely in quality at a high N level; i.e., high yield—high sugar percent, rather than high yield—low sugar percent.
Effects of Environment and Management on Soybean Performance in the Tropics1
Authors: Whigham D. K. , Minor H. C. , Carmen S. G. 
Published: July 2010

AbstractYield potential of soybeans [Glycine max (L.) Merr.] in tropical areas is similar to that in temperate regions. Yield variability among sites indicates that exploitation of this potential under tropical conditions will require a better understanding of how environment and management influence yield. This study was undertaken to investigate the effects of several environmental and management variables on among site variability in yield and other plant characteristics of soybeans in the tropics. Results from 10 cultivars common to International Soybean Program (INTSOY) experiments at 25 sites 10 countries were used in the study. Agronomic variables, expressed as site means, were: yield, seed weight, pod number, number of days to flower, number of days from flowering to maturity, and plant height. Environmental variables measured were: altitude, latitude, daylength, maximum temperature, and minimum temperature. Management variables measured were: amounts of N, P, and K fertilizer applied and mean site nodule number, nodule dry weight, and plant population.Mean site yield was not significantly correlated with any environmental variable measured. The only management variable significantly correlated with mean site yield was nodule dry weight. However, after adjustment for the environmental effects, all management variables together accounted for 56% of the variability in yield among sites. The environmental variables measured, after adjustment for management effects, accounted for only 27% of the variation in yield. Therefore, with respect to the 25 sites studied, the environmental variables were concluded to be less important than the management variables as determinants of yield.The mean site number of days to flower was influenced more by environmental variables than by management variables. Conversely. the mean site number of days from flowering to maturity was more affected by management variables than by environmental variables. Individual variables significantly associated with days to flower were altitude, daylength, maximum temperature, and minimum temperature. Only daylength was significantly correlated with number of days from flowering to maturity.Mean site plant height was positively correlated with latitude, daylength, nodule number, and nodule dry weight, and negatively correlated with applied K fertilizer. Environmental and management effects accounted for similar percentages of among site variability in plant height. Mean site plant height and mean site seed weight were the only agronomic characteristics significantly correlated with mean site yield.The high grand mean yield for the 25 sites studied (2,034 kg/ha) suggest that with adequate management at least some of the cultivars among those tested may perform well in tropical environments. Because of the importance of management in explaining among site variation in yield, considerable effort must be made to train farmers in the proper management of soybeans when they are introduced as a new crop.
Effects of Soil Water Stress on Growth and Nutrient Accumulation in Corn1
Authors: Verasan V. , Phillips Ronald E. 
Published: July 2010

AbstractSoil water stress affects growth and accumulation of plant nutrient ions in corn (Zea mays L.); however, the functional relationship of these are not clearly understood. The objective of this study was to more clearly delineate the effect of soil water stress on growth and accumulation of nutrient ions in corn. Corn was grown in the greenhouse in 20‐liter pots containing soil from the Ap horizon of Maury silt loam (Typic Paleudalfs) under two soil moisture treatments, stressed and non‐stressed. The relationship soil water potential and cumulative evapotranspiration with nutrient accumulation and dry matter production were more significant than the relationship of soil water potential with dry matter production and nutrient accumulation. Since water stress affects turgidity, photosynthesis, respiration, cell enlargement, and other physiological processes of the plant, it was concluded that cumulative transpiration is a better integrator of the effects of these processes on plant growth than is soil water potential.