bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Relative Humidity and Associated Anion on the Absorption of Mn and Zn by Soybean Leaves1
Authors: Rossi N. , Beauchamp E. G. 
Published: July 2010

AbstractThe influence of the relative humidity (RH) and either CI‐ or SO4= as the accompanying anion on Mn and Zn uptake by soybean (Glycine max L. cv ‘Altona’) leaf blades were studied in a growth chamber experiment over a 7‐day period. The quantities of Mn and Zn washed off with water, adsorbed, absorbed, and translocated (by difference) were determined 0.5, 3, and 7 hours and 1, 3, 5, and 7 days after application.The portion of the applied Mn or Zn absorbed by the leaf blades was small. However, the adsorbed quantities of both cations differed with the associated anion, relative humidity, and time of sampling.The rate of absorption of either Mn or Zn was most rapid during the first 24 hours of the 7‐day period. The quantities of Mn and Zn in the leaf blades were larger at 70% RH than at 25% RH. Absorption of both Mn and Zn was greater with the chloride rather than the sulfate salt. The apparent translocation of Zn out of the leaf blades was greater with the sulfate rather than the chloride salt. The apparent translocation of Mn out of the leaf blades was greater with the chloride salt. However, a smaller portion of the absorbed Mn or Zn was translocated out of the leaf with the chloride rather than the sulfate salt. It appeared that salt hygroscopicity had little influence on either Mn or Zn adsorption since there was no interaction between relative humidity and the accompanying anion.
A Visual Irrigation Guide for Maize (Zea mays L.)
Authors: Downey Lloyd A. 
Published: July 2010

AbstractA guide for timing irrigation of maize to minimise water stress was developed. The guide utilized visual estimates of leaf relative water content (RWC) — taking a value of 90% as a critical lower limit. Known relationships between soil matric potential and vapour pressure deficit were used to define the critical RWC in a variable environment. In a semi‐arid situation a simple measurement of temperature could replace the more complicated measurement of vapour pressure deficit. Hence need for irrigation could be ascertained from a graph, using a visual estimate of RWC and a measurement of air temperature. Elsewhere, vapour pressure deficit would have to be used instead of air temperature.
Influence of a Root Crop on Physical Properties of a Medium‐Textured Soil1
Authors: Gerard C. J. , Mehta H. C. 
Published: July 2010

AbstractStudies to evaluate the influences of stage of growth of a root crop and two plant densities on certain physical properties of a medium‐textured soil were conducted. Dynamic changes with time, depth, and plant population occurred on selected physical properties of medium‐textured soils being cropped to fall radishes. After 2 months, radish roots compacted and decreased the permeability of the top 15 cm of soil but had little influence at the 15‐ to 30‐cm depth. However, after 4 months the enlarged radish roots decreased the compactness and increased the permeability of the top 15 cm of soil but compacted the soil at the 15‐ to 30‐cm depth. Field measurements of soil strength described the zone of compaction by radish roots. Compaction by double row radishes was significantly greater than by single‐row radishes.
Influence of Harvesting Method on Rotenoid Yields from Tepbrosia vogelii Hook F.1
Authors: Gaskins M. H. , Stone E. G. 
Published: July 2010

AbstractThe leaves of Tephrosia vogelii, a potential commercial source of rotenoids for insecticides and piscicides, were harvested by two methods: by stripping all leaflets from mature plants at one time, and by clipping the entire plant tops two or more times. The repeated clipping procedure gave higher rotenoid yields. New top growth developed when the plants were first clipped at 45, 60 or 75 cm above ground level. After the second harvest, growth was slow and erratic. The clipping heights of 60 and 75 cm gave best yields with three of four breeding lines tested.The harvested material contained 20 to 30% stems when the clipping procedure was used. These were not woody, and were judged suitable for extraction by any process adapted to leaves alone.
Comparison of Fall, Winter, or Spring N‐P‐K Fertilizer Applications for Corn and Cotton1
Authors: Boswell Fred C. 
Published: July 2010

AbstractField studies compared yields between plow‐down and sidedress N and fall, winter, and spring applied P‐K for corn (Zea mays L.) on Piedmont soil and corn and cotton (Gossypium hirsutum L.) on Coastal Plains acid soils. There were no significant yield differences for the Piedmont soil. For the Coastal Plain soil over a 3‐year period, winter‐ and spring‐applied P and K were superior to fall applications and sidedress N was better than plow‐down N for corn production. Similar N responses were obtained for cotton. However, there was no difference between the fall‐ and winter‐applied P and K, but the spring application yielded significantly (P—.01) more lint cotton than the fall or winter treatments.
Productivity and Quality Response of Five Spring Wheat Genotypes, Triticum aestivum L., to Nitrogen Fertilizer1
Authors: McNeal F. H. , Berg M. A. , Brown P. L. , McGuire C. F. 
Published: July 2010

AbstractFive spring wheat (Triticum aestivum L.) varieties were fertilized with five N treatments in 1969 and two N treatments in 1970 near Belgrade, Mont. The varieties were chosen to represent short, medium, and tall height levels, and each was evaluated for agronomic and quality response.Grain yields of normal ‘Centana’ and medium Centana were similar, even though medium Centana was 25% shorter and the straw yield was 17% less. There was no variety‐by‐fertilizer interaction for yield, indicating that the short and medium height types did not respond any better to N fertilizer than the standard height types. Short Centana had significantly less of its protein translocated from plant to grain than tall or medium Centana. Gain protein percentages decreased as the grainstraw ratio increased, suggesting that the amount of top growth is important in extracting nutrients from the soil.Nitrogen fertilizer significantly increased grain protein percentages, and there was a corresponding increase in loaf volume and grain and texture scores. Baking absorption and mixing time decreased slightly with increasing amounts of N.Water use was similar for the five varieties and increased with increasing rates of N.
Selection of Soils for Pastures Using Common Chemical Measures1
Authors: Beeson Kenneth C. , Goytendia Alejandro , Gomez Guillermo G. 
Published: July 2010

AbstractNutritional data on pasture quality have been correlated with chemical data on related soils to provide criteria for selecting forested or other nonagricultural sites potentially capable of producing pasture of adequate quality for grazing animals in eastern Peru.With the selection of crude protein as being of first importance, a minimum level of 3% organic matter in a soil identified two‐thirds of the soils investigated that produced pastures containing a concentration of 8% or more crude protein in the moisture‐fee forage. Application of the additional criterion for adequate P in the forage, 0.02% of soil N, identified 80% of the soils producing adequate protein.Regression coefficients for concentrations of plant constituents — P, Co, Cu, Mn, Ca — and crude protein on soil measures, pH, total N, organic matter, exchange capacity, and exchangeable Ca are presented.
Cultivar Differences among Calcium‐deficient Kentucky Bluegrass Seedlings1
Authors: Nittler L. W. , Kenny T. J. 
Published: July 2010

AbstractSince many improved Kentucky bluegrass (Poa pratensis L.) cultivars are available for turf purposes, it is important to develop methods of distinguishing among cultivars to insure correctness of labeling of seed in this respect. To detect differences in the seedling stage plants were grown in sand and were supplied either with a complete nutrient solution or with solutions lacking various essential elements. Cultivars differed greatly when plants were grown without calcium. Of 23 cultivars tested, most seedlings of five cultivars were green and healthy after 4 weeks without Ca. Most plants of nine cultivars were very chlorotic, and plants of the other nine were intermediate or were mixtures of healthy and chlorotic plants. Leaf blade tips of many Ca‐deficient plants became red, and cultivars differed in percentage of plants showing this characteristic.Previous research has shown cultivars to differ in development of anthocyanin in lower leaf sheaths. This pigment was increased by moderate Ca deficiency. Our results indicate that growing seedlings without Ca is a useful technique in cultivar identification.
A Preliminary Investigation of Water‐Soluble Inhibitors in Atriplex Polycarpa Using the Fungus Trichoderma Viride1
Authors: Askham Leonard R. , Cornelius Donald R. 
Published: July 2010

AbstractThe leafy material from Atriplex polycarpa contains 1.15% saponin. Comparative inhibition of Trichoderma viride mycelium indicated that saponin from A. polycarpa was either much more potent than commercially available saponin from the bark of Quillaja, or that other water‐soluble inhibitors were also present. Distilled water, dripping through A. polycarpa plants to simulate rain, also removed inhibitory substances from A. polycarpa.
Recording Water Use by Means of Digital Equipment1
Authors: Payne Leland F. , Schreiber H. A. 
Published: July 2010

AbstractA device made of digital components is described that automatically (i) senses a discrete loss of water in individual hydroponic cultures; (ii) stores this information as identifying numbers in an 8 2‐digit word memory; and (iii) displays this information on an electric typewriter at 1‐minute intervals.As many as 16 readings a day can be obtained in a greenhouse, if the ratio of leaf area to water surface area is high enough. This equipment, then, gives a sensitive measurement of water use related to climatic, genetic, or physiologic treatments.
Influence of Mulch on Postharvest Soil Temperatures and Subsequent Regrowth of Alfalfa (Medicago sativa L.)1
Authors: Evenson P. D. , Rumbaugh M. D. 
Published: July 2010

AbstractA study was initiated to evaluate the influence of postharvest soil temperatures on alfalfa (Medicago sativa L.) regrowth. Wheat (Triticum aestivum L.) straw was applied to alfalfa in a variety trial following the second 1968 harvest to reduce soil temperature. Yield increases of mulched plots over unmulched plots were smallest on first harvests (<7%) and largest (43% in 1969 and 1970) on third harvests. Annual yield increases were 11% in 1969 and 17% in 1970. Straw mulch increased plant height, delayed maturity, and increased soil moisture, but did not affect alfalfa stands. Soil temperatures were as much as 9 C lower in mulched as compared to unmulched plots. Largest yield increases from mulching occurred when temperature differentials between the control and mulched plots were the greatest. Apparently, high soil temperatures are a major factor in controlling alfalfa yields.
Herbicides vs Oat Companion Crops for Alfalfa Establishment1
Authors: Schmid A. R. , Behrens R. 
Published: July 2010

AbstractHerbicides are effective for use in establishing alfalfa (Medicago sativa L.) without the use of a companion crop. The objective of the study was to assess the economic feasibility of the herbicide method as compared to the companion crop method and to determine some of its advantages and disadvantages.Productivity of ‘Vernal’ alfalfa established with or without a companion crop was determined at four locations in Minnesota. Oats (Avena sativa L.), harvested for either hay or grain, was used as the companion crop. Four herbicide treatments (EPTC, EPTC + 2,4‐DB, trifluralin, and benefin) were used for weed control when the alfalfa was grown alone. The EPTC soil incorporated treatment plus a postemergence treatment of 2,4‐DB on the alfalfa at the 3 to 4 trifoliolate‐leaf stage was the most effective treatment for controlling weeds.With prices of $27.56/MT for alfalfa hay, $4.20/100 kg for oat grain, and $16.54/MT for oat straw, the net return (excluding costs common to all methods) favored alfalfa establishment with oats harvested for grain and straw.During the establishment year the oat hay companion crop yielded 5.17 metric tons (12% moisture)/ha, while alfalfa grown alone yielded 4.03 metric tons/ha. Oat grains averaged 2,205 kg/ha, and straw yields averaged 5.46 metric tons/ha. Stand counts of alfalfa in the fall of the seeding )year were generally higher for alfalfa grown without a companion crop, but this did not affect the following year's yield.With prices of $27.56/MT for alfalfa hay, $4.20/100 kg for oat grain, and $16.54/MT for oat straw, the net return (excluding costs common to all methods) favored alfalfa establishment with oats harvested for grain and straw.
Nitrate‐N Levels of Perennial Grasses as Affected by Time and Level of Nitrogen Application1
Authors: Ryan M. , Wedin W. F. , Bryan W. B. 
Published: July 2010

AbstractIncreased interest in perennial forage grasses has been further augmented by their versatility in use and by moderating prices of commercial N. Relatively little information is available, however, on nitrate levels in the grasses managed and fertilized to maximizef forage production in the fall. In this study, timing and levels of N applications to orchardgrass(Dactylis glomerata L.), smooth brome (Bromus inermis Leyss.), tall fescue (Festuca arundinacea L.), and reed canarygrass (Phalaris arundinacea L.) were varied. Split or bulk applications of N, ranging from 0 to 540 kg/ha, were made in April, June, and late July. Nitrate ‐N (NO3‐N) percentages greater than 0.15% were considered as potentially “unsafe.” Such percentages were observed in some instances after applications of 135 kg/ha of N in April or June and 540 kg/ha in late July. Results of analyses showed that orchardgrass and tall rescue were significantly higher in percent NO3‐N than either smooth brome or reed canarygrass. Tall fescue tended to be high in percent NO3‐N the fall. Thus, as with sudangrass (Sorghum vulgare sudanense) and orchardgrass, tall rescue may be a forage potentially unsafe under certain conditions of N fertilization.
Yield and N Accumulation of Meadow Forage Fertilized at Advancing Maturity with N1
Authors: Rumburg C. B. 
Published: July 2010

AbstractThese experiments were conducted to compare the efficiency of utilization of N applied early in the spring with that applied at increasingly later stages of herbage maturation and to determine if the N concentration of mature herbage could be increased by delayed applications of N fertilizer. Herbage growth and N accumulation were measured at regular intervals from meadows unfertilized and fertilized with N at increasingly later stages of herbage maturation. Nitrogen increased herbage production, but yields declined as the date of application was delayed. Yields from plots fertilized in June or July were lower by about 10 and 23%, respectively, than yields from plots fertilized in mid‐May. Nitrogen was rapidly accumulated in herbage soon after application, but the maximum accumulated concentrations decreased from more than 3 to less than 2% as the date of fertilization was delayed from May until July.
Oxidant Injury to Shade Tobacco Cultivars Developed in Connecticut for Weather Fleck Resistance1
Authors: Menser H. A. , Hodges G. H. 
Published: July 2010

AbstractThirteen tobacco (Nicotiana tabacum) cultivars developed by the cigar industry for resistance to weather fleck in Connecticut were tested at Beltsville, Md. for their responses to air pollutants. We sought information concerning the degree of fleck resistance among the new cultivars under conditions of high oxidant stress. Most of the improved cultivars showed significantly more resistance to ozone than ‘AST‐C’ (Bel‐C), a cultivar no longer grown because of its susceptibility to weather fleck. Two‐hour fumigations at 10 pphm ozone inflicted less than 10% injury on commercial cultivars. The same dosage injured about 20% of the leaf surfaces of Bel‐C. The increase in leaf injury to the commercial cultivars was more pronounced between ozone rates of 15 and 20 pphm, compared to 10 and 15 pphm. Ozone used at 20 and 25 pphm produced about 25% injury on the two most resistant selections, ‘GC 18’ and ‘CCC‐L.’ The same rates destroyed 60 to 70% of the leaves of Bel‐C. Weather fleck evaluations in the field disclosed that photochemical oxidants injured less than 3% of the leaf area of three commercial cultivars, but damaged 55% of the leaf surfaces of Bel‐C. The most leaf injury to an improved cultivar was 25%. Improved cultivars displayed less than 20% fleck damage in the first and second harvest primings, compared to 75% damage in the same two primings of Bel‐C. Results clearly demonstrate the success achieved in controlling weather fleck by using plant breeding methods.
Germination and Establishment of Salsola in Relation to Seedbed Environment. I. Temperature, Afterripening, and Moisture Relations of Salsola Seeds as Determined by Laboratory Studies1
Authors: Young James A. , Evans Raymond A. 
Published: July 2010

AbstractOur purposes were to investigate the germination characteristics of Russian thistle (Salsola kali var. tenuifolia Tausch.) and to identify the characteristics that control the periodicity of germination for this species. Germination tests were conducted at constant and alternating temperatures from —9 to 30 C and at various moisture potentials. Seeds for testing were collected at intervals from maturity until the following spring. Seeds of Russian thistle have temperature‐dependent afterripening requirements that depress germination at high and low temperatures soon after maturity. There are several distinct steps in the phenological development of the germination of Russian thistle seeds. The rate of development is extremely rapid at high temperatures. When afterripening requirements are satisfied in March and April germination will occur with subzero C nighttune temperatures and 2 C daytime temperatures. Germination was very low on the surface of a media held at —0.1 bars matric potential if the atmosphere around the seeds has a moderate to high moisture stress. Afterripening requirements are the major, but not the only factor, governing the periodicity of germination of Russian thistle seeds.
Some Factors Affecting Asymbiotic Nitrogen Fixation in Soils as Measured by 15N Enrichment1
Authors: Fehr P. I. , Pang P. C. , Hedlin R. A. , Cho C. M. 
Published: July 2010

AbstractThe use of the isotopic 15N technique to measure asymbiotic N fixation in soils has been reported by very few workers, despite the obvious advantages of the technique in assessing the importance of this fixation in agricultural soils.The effect of glucose plus cellulose (0 and 0.5% glucose + 0.5% cellulose), glucose alone (0, 0.04, 0.2, 1.0 and 5.0% on dry soil weight basis), incubation temperature, method of soil aeration, and atmospheric composition on N fixation in soil in a closed system using 15N was investigated.Significant fixation was observed mainly when a readily available supply of energy such as glucose plus cellulose or glucose alone was added to the soil. Aerating the energy‐enriched soil by diffusion resulted in greater N fixation under an aerobic and anaerobic atmosphere than aerating by a continuous air flow in a closed system.The optimum glucose concentration was 1% at the 15 and 35 C incubation temperatures employed, while 5% glucose resulted in greater fixation at the 25 C temperature. Generally, more N was fixed at 15 and 25 C than at the 35 C incubation temperature.
54Mn Incorporation into Plants and Subsequent Metabolism by Rats1
Authors: Lassiter J. W. , Coston M. L. , Miller W. J. , Morris H. D. 
Published: July 2010

AbstractLittle information was available on metabolism by animals of Mn in chemical forms existing in plants. Incorporation of 54Mn into plants is a practical way to facilitate such studies; however, before this could be done, studies were required on factors affecting 54Mn uptake by plants. Accordingly, the influence of dose levels and dose‐date and harvest‐date on 54Mn uptake by four plant species were studied. Also, the absorption by rats of the 54Mn incorporated into plants was studied.Increasing 54Mn dose level from 0.86 to 8.6 and 86 µCi decreased uptake. Applying the dose 19 days after planting increased 54Mn uptake, as compared to applying it 12 days after. Uptake by soybeans [Glycine max (L.) Merrill] was higher than by corn (Zea mays L.), millet (Panicum sp.), or sorghum [Sorghum bicolor (L.) Moench] ✕ sudan (Sorghum vulgare sudanense), especially at the lowest dose level.Livers of weanling male rats fed 54Mn forage contained only one‐third as much 54Mn as those of rats given 54MnCl2. Similar effects were evident in kidneys and duodenum. Thus, Mn in forage was much less available to rats than Mn as the chloride illustrating the importance of chemical form of Mn on its metabolism and value to animals.
Concentrations of N and P in Young Corn Plants, as Affected by Various Growth‐limiting Factors1
Authors: Terman G. L. , Noggle J C , Engelstad O. P. 
Published: July 2010

AbstractYields and concentrations of N and P were studied in young corn (Zea mays L.) plants as a basis for correct interpretation of plant analysis results. The corn was grown on soils deficient in these nutrients in several greenhouse pot experiments comparing rate, source, and placement of N or P. Results from such pot experiments were satisfactory for establishing minimum and critical nutrient concentrations in corn if various growth‐limiting factors were properly corrected. These included age of plant, application rates of one or more deficient nutrients, and adequacy of other yield‐limiting factors, including liming and other nutrients.The minimum concentrations of total N or of P in corn forage appear to be rather constant for a given age of plant and can be more accurately estimated than critical concentrations can. The results suggest the estimation of critical values from the minimum concentrations.C‐type curves resulting from plots of dry matter yield vs nutrient concentration could be explained largely by dilution resulting from growth response to application of a second deficient nutrient.
Effect of Irrigation, Harvest Interval, and Nitrogen on the Yield and Nutrient Composition of Napiergrass (Pennisetum purpureum)1
Authors: Capiel Modesto , Ashcroft Gaylen L. 
Published: July 2010

AbstractStudies were conducted in a subhumid area of Puerto Rico to investigate the main effect and the interrelations of harvest interval, irrigation, and N fertilization on the yield and nutrient composition of napiergrass (Penniseturn purpureum). Harvest interval exerted the main effect on the dry matter yield of the forage. Nitrogen fertilization and irrigation also had highly significant effects. Irrigation interacted significantly with harvest interval to influence forage yield. The increase in yield as a result of a longer harvest interval was nearly 92% greater on irrigated than on nonirrigated plots.Nitrogen fertilization produced a highly significant increase in the protein yield of the forage. No other management treatment appreciably influenced protein yields. Significant negative correlations were obtained between yield and both N and K composition for the forage on the frequently harvested, irrigated plots. Both nutrients were at lower concentration in the forage produced in harvest periods that had high yields.