bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relation of Light Reflectance of Six Barley Lines with Chlorophyll Assays and Optical Film Densities1
Authors: Cardenas R. , Gausman H. W. 
Published: July 2010

AbstractLight reflectance (R) and chlorophyll (chl) were measured on leaves of three pairs of isolines of barley (Hordeum vulgare L. [H. sativum, Pers.]) to learn if differences in chl concentration among the lines could be photographically detected for remote sensing purposes. Photographs of the plants were taken with Kodak Ektachrome MS Aerographic 2448 (conventional color [CC]) and Kodak Aerochrome Infrared 2443 (CIR) films.Clorophyll concentrations of the six barley lines were negatively correlated (r −0.87, p = 0.05) with spectrophotometrically measured light reflectance R at the green peak of the 550‐nm wavelength. Golden Liberty had the lowest total chl and the highest R. Liberty and Betzes had the second and third highest chl concentrations (6.70 and 5.65 mg, respectively) and had the lowest R of all lines. Golden Liberty and Betzes had a lower concentration of chl b relative to chl a than the other lines.Optical count readings made with a densitometer on CC and CIR transparencies were positively correlated with chl concentrations (p = 0.05, 0.88, 0.87, 0.94, and 0.94 for CC film + no filter, CC film + green filter, CIR film + no filter, and CIR film + green filter, respectively).Discrimination among barley lines was better on CIR than on CC films. With CIR film, highest readings (97.0, no filter and 98.7, green filter) were obtained with Compana, and lowest readings (47.1, no filter and 46.6, green filter) were obtained with golden Liberty.
Nitrate Accumulation in Table Beets and Spinach as Affected by Nitrogen, Phosphorus, and Potassium Nutrition and Light Intensity1
Authors: Cantliffe D. J. 
Published: July 2010

AbstractThe objective of this research was to determine the effects of varying levels of N, P, and K fertilizer and light intensity on nitrate accumulation in species grown for human consumption. In greenhouse experiments, table beets (Beta vulgaris L.) and spinach (Spinacia oleracea L.) were grown in fine sandy loam soil at three levels of N, P, and K fertilizer in a 33 factorial design. Plants were grown under two light intensities, 1.08 ✕ 104 lux or 3.23 ✕ 104 lux. Nitrate, total N, P, and K were determined on freeze dried table beet leaf blades and roots and on spinach leaves.Fertilizer N had the greatest influence on NO3 accumulation in all three tissues studied. Varying the rate of fertilizer P had no effect on NO3 accumulation. Plants of both species grown with the highest rate of K and under the lower light intensity accumulated significantly more NO3‐N than other plants receiving less K. Table beet leaf blades contained three times more NO3 than roots. Lowering the light intensity from 3.23 to 1.08 ✕ 104 resulted in a significant increase in NO3‐N in all tissues tested.Total N concentration increased in all tissues with an addition of N fertilizer or by a reduction in light intensity. In spinach, total N was lower in plants receiving K fertilizer. P and K were lower in beet and spinach leaves that received N fertilizer. Light intensity had no influence on P concentration, while all tissues grown at 1.08 ✕ 104 lux contained more K than tissue grown at 3.23 ✕ 104 lux.Any factor which increased the total N concentration of the tissue resulted in a corresponding increment in the NO3 concentration.
A Photoelectric Seed Counter1
Authors: Fisher H. D. , Brown M. J. 
Published: July 2010

AbstractSmall scale yield studies, germination tests, controlled plantings, and packaging often require the counting of large numbers of seeds. The system described in this paper uses a photosensitive detector and a vacuum pickup to count individual seeds and gives a direct digital readout. The count rate is limited only by how quickly the seeds can be fed through the counting tube without clogging it or having them touch each other. This greatly speeds seed counting, eliminates operator error, and reduces operator fatigue.With the addition of a relatively simple predetermining circuit, a fixed number of seeds may be counted and a control function can be exercised. This capability is immediately applicable to packaging or repetitious batching of seeds. Zero error for any given number of seeds is attainable if the seeds are fed through the count tube carefully because of the completely digital nature of the circuit.
Corn root‐Configuration Response to Soil Temperature and Matric Suction1
Authors: Allmaras R. R. , Nelson W. W. 
Published: July 2010

Soil temperature and water variables imposed on the roots of corn (Zea mays L.) in field plots influenced root development. Responses were measured in separate portions of the root system where adventitious roots initiate and subsequent root elongation and branching occurs. These portions of the corn root system are separated far enough to permit specific field management for each portion. Temperature and water variables were produced by combinations of straw‐mulch strips and interrow tillage.Initiation of adventitious roots in the 0‐ to 10‐cm soil depth was dominantly influenced by soil temperature in the row.In soil depths below 10 cm, a functional relation between root configuration and the interrow‐minus‐row soil temperature, and matric suction described the elongation and branching responses subsequent to root initiation. In the year of lower soil temperature and higher moisture (measurements were made in two growing seasons), higher interrow temperatures stimulated branching and elongation, but in the year of higher soil temperature and moderate moisture conditions, responses to temperature were negligible. Higher interrow moisture stimulated branching and elongation in both years as long as the average matric suction was greater than about 85 mb.These explicit descriptions of corn‐root‐configuration response show the importance of soil temperature management in the row and water management in the interrow. This approach permits more extensive use of the row‐interrow concept for design of minimum tillage and residue management systems.
Response on One Winter Wheat and Two Spring Oat Varieties to Foliar Applications of 2‐Chloroethyl Phosphonic Acid (Ethrel)1
Authors: Brown C. M. , Earley E. B. 
Published: July 2010

AbstractEthrel (2‐chloroethyl phosphonic acid) has significant effects on growth and development of corn (Zea mays L.) and soybeans (Glycine max (L.) Merrill) and has been suggested as a potential male gametocide for the production of hybrid wheat. The purpose of this study was to further elucidate the response of winter wheat (Triticum aestivum L. em Thell.) and spring oats (Avena sativa L.) to foliar applications of Ethrel.Ethrel was foliarly sprayed on the winter wheat variety ‘Knox 62’ at 0.28, 0.56, 1.12, and 2.24 kg/ha when plants were in the late tillering, early boot, late boot, and heading stages. The magnitude of effects was closely related to rate and stage of application. Rates of 0.28 or 0.56 kg/ha applied at early and late boot stages of development effectively reduced height and lodging and in several cases accounted for significant increases in yield. Higher rates (1.12 or 2.24 kg/ha) reduced height and lodging but usually decreased yields when applied at the boot stages of growth. The 1.12 and 2.24 kg rates applied at heading stage did not decrease yield but were less effective in reducing height and lodging. Higher yields in the Ethrel‐treated plots were generally associated with somewhat heavier seeds.Although we did not bag spikes or observe pollen from treated plants, the excellent seedset we obtained indicated that either the Ethrel treatments did not cause significant male sterility, or if they did, it was completely obscured by cross fertilization. Clearly female fertility was not impaired to any great extent by the Ethrel treatments.Our results with the same rates and stages of application for two oat varieties suggested that Ethrel has little potential for use on spring oats. Beneficial effects, such as reduced height and lodging, were accompanied by reduced yields. Even the lowest rate of application (0.28 kg/ha) applied at the late boot stage of growth caused a 40% reduction in grain yield. Reduced yields were accompanied by severe blasting of florets. Although the applications made at heading stage did not reduce yields, they were not very effective in reducing height or lodging.
Compatibility of Five Herbicides with a Suspension Fertilizer1
Authors: Meyer L. J. , Murphy L. S. , Russ O. G. 
Published: July 2010

AbstractThe chemical compatibility of five different herbicides (a thiocarbamate, an amide, a thiocarbamate‐triazine mix, a urea‐triazine mix, and an aniline) with a suspension fertilizer (containing 15% N, 6.5% P, and 12.5% K) was studied. Effectiveness of combined materials, applied after being stored in contact for various periods of time, was compared with that of materials applied separately. Nutrient composition (N, P, K), nutrient uptake, and dry matter yields of plants grown in a growth chamber were used to evaluate fertilizer effectiveness. Herbicide phytoxicity was evaluated by visual and pictorial comparisons. Physical compatibility of all mixtures used was determined to ascertain whether the mixtures would mix satisfactorily for field application.All combined materials were both physically and chemically compatible and all herbicides were as effective when applied in combination with the fertifizer as when applied separately. All herbicides studied can be mixed with the suspension fertifizer prior to application and remain effective during the growing season, but agitation is required during storage.
Indexes of Sulfur Deficiency in Alfalfa. I. Extractable Soil SO4‐S1
Authors: Westermann D. T. 
Published: July 2010

AbstractSulfur deficiencies occur on many of the undeveloped agricultural soils found in the mountain valleys of the western United States; however, the majority of the S soil‐test correlation studies have been conducted on leached and weathered soils. Identification of S deficiency on alfalfa (Medicago sativa L.) growing in three mountain valleys permitted the collection of S soil‐test correlation data for these undeveloped soils. This paper reports the relationships found between extractable soil SO4‐S levels and the response of alfalfa to S fertilization.Soil samples were taken from 13 experimental sites before active plant growth commenced in the spring in 30‐cm depth increments to 92 cm. Soil SO4‐S was extracted by water, 0.1 M LiCl, and 0.032 M KH2PO4 and measured by the methylene‐blue reduction method. Significant correlations were obtained between the SO4‐S extracted by all three extractants from the 0‐ to 30‐cm soil layers and relative forage yields and total S uptake by the first harvest of alfalfa at early bloom. Critical soil SO4‐S levels of 3.0, 3.0, and 4.0 ppm in this soil layer were found when extracted by water, LiCl, and KH2PO4, respectively. Inclusion of KH2PO4‐extractable SO4‐S to 92 cm did not improve the curvilinear regression relationships, nor did inclusion of percent soil organic matter. Increasing the soil:extractant ratio from 1:2 to 1:3 did not significantly change the amount of SO4‐S extracted by the KH2PO4 solution. The 0.1 M LiCl solution is recommended for extracting SO4‐S from soils with relatively small amounts of absorbed SO4‐S.
Effect of Lime, Sulfur, and Molybdenum on N2 Fixation and Yield of Dark Red Kidney Beans1
Authors: Janssen K. A. , Vitosh M. L. 
Published: July 2010

AbstractSymbiotic nitrogen fixation by the Rhizobium‐legume association of fieldbeans does not provide sufficient nitrogen for optimum yield under Michigan growing conditions. Consequently, an average of 44.8 kg/ha (40 lbs/A) of supplemental nitrogen is applied to these legume crops each year. This results in a sizeable investment for the growers and also increases the potential for N loss by leaching and runoff.The purpose of this study was to determine whether lime, S, and/or Mo might be limiting N2 fixation and bean yield of dark red kidney beans (Phaseolus vulgaris L.) in the field. Two acid sandy soils 40.2 km (25 miles) apart, N‐S direction, suspected of being deficient in S and Mo, were selected for this study. Lime rates (0, 2,800, and 5,600 kg/ha), S rates (0 and 45 kg/ha), and Mo rates (0 and .07 kg/ha) were compared in a factorial design. Symbiotic nitrogen fixation was measured by the acetylene reduction assay. Soil samples were collected and bean yields were recorded.Sulfur increased nitrogen fixation (acetylene reduction activity) nearly 60%. The lime and Mo treatments had little influence on nodule activity. The average yield of beans was increased 10% by the 2,800 kg/ha lime rate and 26% by the 5,600 kg/ha lime rate. The Mo seed treatment reduced yield 7%. Yield response to S was 26% at the zero lime rate, 12% at the 2,800 kg/ha lime rate, and 10% at the 5,600 kg/ha lime rate. Soil test results showed that lime increased the amount of available S in the soil.These data suggest that lime and S are limiting bean yield on certain acid sandy soils in Michigan. It also appears that where soils are S deficient symbiotic nitrogen fixation is being restricted.
Soil and Plant Factors Influencing Accumulation of Dry Matter in Burley Tobacco Growing in Soil Made Acid by Fertilizer1
Authors: Sims J. L. , Atkinson W. O. 
Published: July 2010

AbstractA field experiment was conducted to elucidate factors influencing dry matter accumulation in tobacco (Nicotiana tabacum L. cv. ‘Burley 21’) growing in soil whose acidity was increased by fertilizer. Relatively large amounts of commercial fertilizers commonly are added to soil in burley tobacco production and knowledge of the effects of such additions on dry matter accumulation may lead to increased yields of cured leaf and improved usability of cigarette smoke. Samples of soil and plant material were obtained at varying dates during the growing season and were chemically analyzed. Varying soil pH levels were obtained from applications of N as ammonium nitrate at rates of 0, 90, 180, and 360 kg N/ha.The addition of N fertilizer to Maury silt loam soil with an initial pH of 6.2 significantly increased exchangeable Mn and decreased soil pH, exchangeable Ca, and concentrations of available MoO4−2 and H2PO4−. Exchangeable Mg and K were little affected by N fertilizer at any sampling date. Much of the decrease in exchangeable Ca may be attributed to leaching with NO3− by excessive rainfall early in the season. Evidence indicated some delay of nitrification of NH4+ in plots fertilized at the 360 kg N rate.Nitrogen fertilization of tobacco increased concentrations of Mn in leaves, but levels were not judged to be excessive for normal growth. A tendency existed for concentrations of Ca and Mg to be decreased by N at 40 days after transplanting and concentrations were near deficiency levels for Ca at this date, although exchangeable soil Ca levels exceeded 1500 ppm. In contrast, at 77 days and at harvest, N fertilizer significantly increased plant concentrations of Ca and Mg. Molybdenum concentrations in leaves from high N plots were only 20 to 50% of those in plots unfertilized with N. Concentrations of MoO4−2 in leaves from fertilized plots were near deficiency levels for most of the growing season. The data suggested interaction of MoO4−2 and Mn, and of Mn with Ca and Mg within the plant.Correlation and regression analyses revealed significant relationships of soil measurements near transplanting and dry matter at 40 days and of plant constituents and dry matter at all dates. Results indicated the depression of dry weight by N fertilizer noted previously during early growth was the direct or indirect result of fertilizer‐induced soil acidity.
Cation‐Anion Balance of Field‐Grown Crops. II. Effect of P and K Fertilization and Soil pH1
Authors: Banwart W. L. , Pierre W. H. 
Published: July 2010

AbstractPlant species differ in their cation‐anion balance, but the organic anion content (C‐A), excess‐base (EB), and EB/N ratio of a given plant species may vary considerably when grown under different environmental conditions. Nitrogen fertilizers, for example, increase the organic anion content of certain crop plants and alter their effect on soil acidity by reducing the EB/N ratio. The primary objective of this study was to determine the effect of a wide range in amounts of P and K fertilizers and of soil pH on the cation‐anion balance of several crop species grown under field conditions.Leaf and plant samples of corn (Zea mays L.) and plant samples of alfalfa (Medicago sativa L.) and oats (Avena sativa L.) were taken for analysis from plots of several field experiments that had received a wide range in amounts of P and K or of ground limestone.In general, phosphorus and potassium fertilizers decreased the C‐A and EB contents of corn leaves, oats, and alfalfa. The effect of P and K additions in reducing C‐A and EB seemed less where they had the least effect in increasing crop yields; and in some experiments, K additions had little or no effect on C‐A, EB, or yield. Limestone additions on two soils, resulting in pH changes from below 6.0 to above 7.6, increased C‐A and EB of corn leaves slightly in one experiment, but had no significant influence on C‐A, EB, or yield in the other.Potassium fertilizers lowered the EB/N ratio of corn leaves. However, K and P fertilizers and limestone additions resulted in only very slight changes in the EB/N ratio of corn, oats, and alfalfa plants; and no change in EB/N was observed in several of the comparisons. Thus, on the basis of their effect on the EB/N ratio of the crops harvested, P and K fertilizers and soil pH should not alter the plant effect on the base status of soils.
Crop Recovery and Nitrification of Fall and Spring Applied Anhydrous Ammonia1
Authors: Chalk P. M. , Keeney D. R. , Walsh L. M. 
Published: July 2010

AbstractTo evaluate the relative agronomic efficiency of and potential NO3, pollution by fall and spring applied anhydrous NH3, N uptake and yield response by corn, and detailed sampling of the NH3, bands were conducted. Nitrogen significantly increased grain yield and N uptake by corn (Zea mays L.) on a Plano sil (0.216% N) and a Pella loam (0.447% N) in south central Wisconsin. There were no differences between fall and spring application of N. Crop recovery of applied N depended on soil type and rate of application, and at most amounted to 40% of the N applied. Depending on rate of application, from 68 to 86% of the fall‐applied NH3, was nitrified before mid‐May. Nitrite accumulated within both fall and spring applied bands, the highest concentrations being detected in early spring within fall applied bands. Persistence of NO2 was more prolonged on a neutral than on a slightly acid soil. Accumulation of NO2 must be considered undesirable because of possible phytotoxicity and losses through biological or chemical denitrification, and fall application appears to offer a great potential for these processes to occur.
Use of Soil Sterilants to Defoliate and to Terminate Growth of Irrigated Cotton1
Authors: Gardner B. R. , Troutman J. L. 
Published: July 2010

AbstractThe conventional approach of applying harvest‐aid chemicals to leaves of luxuriantly growing cotton plants, Gossypium hirsutum L., often results in partial or top defoliation followed by secondary growth. This study was initiated to test a new concept of cotton defoliation. The application of 61 liters/ha of a 32.7% aqueous solution of sodium methyl dithiocarbamate in the irrigation water to luxuriantly growing cotton plants resulted in termination of plant growth and complete leaf defoliation. Defoliation was completed within 10 days from time of application with full size, immature bolls opening in about 20 days. There was no evidence of plant regrowth after 75 days. The cotton plants were ideally suited for mechanical harvest. Although the chemical is too expensive to be economically feasible, we suggest that luxuriantly growing cotton plants can best be defoliated by destroying the conductive tissues of the root and/or lower portion of the stem and that further testing of this concept be initiated.
Relation of Soil Water Potential to Stomatal Resistance of Soybean1
Authors: Brady R. A. , Goltz S. M. , Powers W. L. , Kanemasu E. T. 
Published: July 2010

AbstractThis research was undertaken to establish a meaningful relationship between stomatal resistance of soybeans and soil water potential. The main objectives were to establish this relationship and examine some of the factors affecting measurements of stomatal resistance of soybeans. Stomatal resistance in the soybean leaves was measured with a stomata porometer and plotted against soil water potential.A definite relationship was determined in two consecutive growing seasons between the soil water potential and stomatal resistance. Adaxial stomatal resistance increased rapidly when soil water potentials decrease to near −4 bars.It was found that stomatal resistance of upper canopy leaves were not affected by the physiological stage of growth of the whole plant. The difference in stomatal resistance of well‐irrigated and nonirrigated soybeans was distinct, and stomatal resistance showed promise in determining irrigation schedules.
Effects of Soil pH on Forage Yield, and Chemical Composition of Sorghum and Millet1
Authors: Walker Milton E. , Marchant Warren H. , Ethredge W. Jerome 
Published: July 2010

AbstractMillet [Pennisetum typhoides (Burm.) Stapf and Hubbard] yields more forage than sorghum [Sorghum bicolor (L.) Moench] does in certain areas of the Southern Coastal Plain. Yield differences are associated with low soil pH in some instances. Experiments were conducted to elucidate the relation between soil pH, forage yield, and selected chemical composition of sorghum and millet.Management practices and plant nutrient applications were applied in a manner and at a level shown by other experiments to be adequate. The forage from both crops was analyzed for N, P, K, Ca, Mg, Al, and Mn. Upon completion of the experiment, soil samples were analyzed for P, K, Ca, Mg, Al, and Mn and soil pH was measured. Millet forage yield was unrelated to the soil pH in the pH range used. Sorghum forage yield increased 2,000 kg/ha when soil pH increased from 5.2 to 5.6. The concentration of Mg in sorghum forage was found to be greater at soil pH of 5.8 and above, while the concentration of Al and Mn decreased at a soil pH ≥ 5.2. The concentration of Ca increased more at soil pH ≥ 5.8; while the concentration of Al and Mn decreased at a soil pH ≥ 5.2. The concentration of Ca increased in millet forage at a soil pH ≥ 5.2; while P and Mg content increased at a soil pH ≥ 5.8.Based on this study, it is recommended that liming acid soils in the Southern Coastal Plain to increase soil pH increases sorghum forage yields and improves the mineral nutritional quality of both sorghum and millet forage.