bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonionic Surfactant‐soil Interaction Effects on Barley Growth1
Authors: Valoras N. , Letey J. , Osborn J. 
Published: July 2010

AbstractResearch was conducted to integrate previously reported independent observations on surfactant adsorption, microbial degradation, uptake, and translocation, and on surfactant effects on plant growth in solution and soil cultures. Adsorption isotherms were measured for two nonionic surfactants and three soil materials. The shape of the adsorption isotherm was dependent upon both surfactant and soil properties. Barley (Hordeum vulgare L.) plants were grown in solution culture containing various concentrations of surfactant and in soil wet with surfactant solutions. Application of surfactant solution to soil reduced its toxicity to plants because of surfactant adsorption by the soil. The adsorption isotherm was used to calculate concentration of surfactant remaining in solution after application to soil. The effect of surfactant on plant growth was approximately the same in solution and soil cultures when the results were compared on the basis of solution concentration in the soil following adsorption. Less than 1% of the surfactant applied to soil was taken up and translocated in the barley plants. The difference between amount of a 14C‐labeled soil penetrant (an alkyl polyoxyethylene ether) applied and recovered in the soil and plant at the end of the experiment agreed with expected microbial degradation rates previously measured.
Sloughing Guard for Sequential Depth Soil Sampling1
Authors: Smith D. T. , Fickle J. S. , Abernathy J. 
Published: July 2010

AbstractAfter field application of pesticides, soil may be sampled at several depths to ascertain persistance and movement in the profile. A simple, inexpensive device was designed to facilitate manual sampling and preserve sample integrity for sandy or loose surface soil. When samples are obtained from several depths, the guard prevents loose soil on the surface from sloughing into the hole and contaminating samples from subsequent depths.
Response of Soybeans in Maturity Groups V, VI, VII, and VIII to End‐trimming1
Authors: Boerma H. R. , Marchant W. H. , Parker M. B. 
Published: July 2010

AbstractAccurate field plot technique is an important factor in soybean [Glycine max (L.) Merr.], cultivar and strain seed yield evaluation. Information on end effects in seed yield trials of soybeans grown in the southern region of the US is not available. The purposes of the present study were to determine the importance of these effects and the measures required to control them.Three soybean cultivars each in maturity groups V, VI, VII, and VIII were end‐trimmed by removing 0.46 m from both ends of the harvest rows of plots at the early vegetative, beginning flowering, physiological maturity, and harvest maturity growth stages. Seed yield was determined on consecutive 0.3‐m sections from each end of the harvest rows and a 0.6‐m section from the middle of each row. The data indicated that removing 0.76 m from the end of plots at physiological maturity or a later stage should eliminate yield inflations.In other tests 5, 4, 7, and 8 cultivars or strains in maturity groups V through VIII, respectively, were planted on 7 May and 20 June and the seed yield determined by both including and excluding the outermost 0.61 m from both ends of the 6.1‐m harvest rows. Significant changes in rank and in differences among genotypes were obtained with and without elimination of end effects. These differences existed both among and within maturity groups. Plant height affected yield inflation more than maturity date.
Yield Potential in a Dwarf Spring Wheat and the Effect of Carbon Dioxide Fertilization1
Authors: Fischer R. A. , Aguilar M. I. 
Published: July 2010

AbstractCarbon dioxide fertilization provides a way of increasing crop photosynthesis and can be used to indicate when and to what extent crop photosynthesis limits grain yield and its components. A CO2 fertilization experiment was conducted using a dwarf spring wheat (Triticum aestivum L. ‘Yecora 70’) in each of three winter cropping cycles (1970‐73) in northwest Mexico. The wheat was grown in the field under irrigation and optimal agronomy. Small areas of crop (1 to 2 m2) were enclosed in transparent chambers ventilated with air enriched to approximately 750 ppm CO2; chambers ventilated with normal air and unenclosed areas of crop acted as controls. Fertilization was carried out in separate plots during each of four 1‐ month periods covering the crop cycle.Fertilization with CO2 increased crop dry matter production. Grain yield was either unaffected or increased by up to 23% by extra CO2. Biggest yield increases came generally from CO2, in the 2nd and 3rd months and were associated with more spikes/m2 and grains/spikelet, hence more grains/m2. During the 4th month or grain filling period, kernel weight and grain yield were significantly increased in 1972, but clearly not in 1973. Results indicate greatest yield limitation by crop photosynthesis in the 2 months preceding grain filling, when grains/m2 is determined. They are discussed in relation to adjacent shading experiments with the same cultivar, to other CO2 fertilization studies with wheat and other crops, and to possible avenues for increasing yield potential.
Impact of Residual Mineral N in Soil on Grain Protein Yields of Winter Wheat and Corn1
Authors: Olson R. A. , Frank K. D. , Deibert E. J. , Dreier A. F. , Sander D. H. , Johnson V. A. 
Published: July 2010

AbstractFertilizer N has become a major cost input in the production of winter wheat (Triticum aestivum L.) and corn (Zea mays L.) with uncertainties remaining as to rates required for effecting optimum grain and protein yields without environmental pollution implications. For this reason investigations were conducted with the two crops to determine optimum rate of fertilizer N for grain and protein yields with varied levels of residual mineral N in the rooting profile of soil to 180 cm depth at planting. Fertilizer rates employed for wheat in 118 farmers' fields ranged from 0 to 67 kg N/ha by 22.5 kg increments broadcast in the spring and for corn in 17 farmers' fields from 0 to 225 kg/ha by 45 kg increments sidedressed at 30 to 45 cm growth stage.Residual mineral N was found to exert major influence on grain protein percentage and protein yield of both crops within nominal rates of N fertilizer application. The magnitude of residuals varies with the soil environment and amount of prior fertilizer use on the soil. The data reveal that grain yield response of wheat to applied N is unlikely when soil residual mineral N exceeds 120 kg/ha and for irrigated corn around 240 kg/ha at the yield levels of approximately 25 to 30 quintals/ha of wheat and 85 to 90 quintals of corn obtained in these experiments. Maximum protein yield for wheat required an additional 50 to 60 kg N/ha and for corn 60 kg, economics of which can be ascertained only with knowledge of the unit nutritional value of the produce in relation to the unit cost of N applied.
Performance of Five Warm‐season Perennial Grasses Grown in Southern Mississippi
Authors: Brown W. E. , Spiers J. M. , Thurman C. W. 
Published: July 2010

AbstractIncreased interest in summer forage production in southern Mississippi prompted this study, comparing the performance of five perennial grasses. Plots of ‘Coastal,’‘Alicia,’ ‘Coastcross‐1,’ and Common bermudagrass (Cynodon dactylon L. Pers.) plus ‘Pensacola’ bahiagrass (Paspalum notatum Flugge) were harvested monthly during the 1973 growing season and at 2 and 4‐week intervals during 1974. Parameters measured were dry matter yield, digestible dry matter, and crude protein. Results show Alicia and Coastcross‐1 bermudagrass exhibited vigorous 1st‐year growth, but performance decreased during the 2nd year, especially of Alicia. Common also decreased in forage production in the 2nd year. Coastal maintained approximately the same level of growth both years, and bahiagrass increased in total yield during the second growing season.
Foam Application of Growth Retardants to Turfgrasses1
Authors: Aagesen G. J. , Elkins D. M. 
Published: July 2010

AbstractChemical growth retardants have been used on a limited scale to reduce mowing maintenance of turfgrasses. In recent years foam materials have served as carriers for pesticides and most recently for growth retardants. A foam carrier for retardants could offer the possible advantages of serving as an effective marker during application, reducing spray drift, and increasing growth retardant effectiveness. Four field studies were conducted in 1973 and 1974 at Carbondale, Ill. to compare foam application of growth retardants to conventional spray‐application on established turfgrasses. Three chemical growth retardants were tested on a ‘Park,’ Newport,' and ‘Delta’ blend of Kentucky bluegrass (Poa pratensis L.) and a pure stand of ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.) with three commercially available foaming agents.Growth retardant treatments resulted in lower grass height and decreased dry matter yields. In general, N‐phosphono methylamino‐diacetic acid (MON‐820) gave the best results with 3‐trifluromethyl‐sulfonamido‐p‐acetotoluidide (Sustar) intermediate and diethanolamine salt of 6‐hydroxy‐3‐(2H)‐pyridazinone (maleic hydrazide) least effective. Considerable losses in green color occurred with retardant treatments that gave the best growth retardation. The foam materials Fomex and Foamspray used as growth retardant carriers were equally effective as retardants applied by conventional spray methods. Thermofoam was not effective as a growth retardant carrier.Growth retardants in foam carriers proved effective in reducing growth of turfgrasses. These findings show that foam application of retardants to roadbank vegetation merits investigation. Feasibility studies should also be conducted on the possibility of marketing a selected growth retardant with foam in an aerosol spray can or garden hose attachment as a home lawn care product.
Anhydrous Ammonia Applications During Fallow for Winter Wheat Production1
Authors: Smika D. E. , Grabouski P. H. 
Published: July 2010

AbstractAnhydrous ammonia (NH3) was applied at the rate of 67 kg/ha on 20 July and 8 September the summer after harvest and 15 May, 30 May, 15 June, 30 June, 15 July, 30 July, and 15 August the following summer during two 14‐month fallow periods on Aridic Haplustoll and Torripsamment soils. The study was conducted to determine the ammonia application date during the 14‐month fallow period which produced the soil water‐soil NO3‐N distribution in the soil resulting in the maximum protein levels and grain yields of winter wheat (Triticum aestivum L.). Soil NO3‐N and soil water contents were determined to a 180 cm depth on each application date and at wheat seeding (15 September). In the Aridic Haplustoll soil, NH3 had to be applied in the summer after harvest (over 1 year before wheat seeding) for maximum NO3‐N accumulation in the soil between 60 and 120 cm which produced the highest protein grain (14.5%) and the highest yield (3,269 kg/ha). In the Torripsamment, NH3 applications between 15 May and 30 June the year of wheat planting produced highest protein grain (13.4%) and highest grain yields (2,688 kg/ha). However the optimum NH3 application date to produce the desired NO3‐N accumulation in the 60 to 120 or 150 cm soil depths in the Torripsamment was not determined in this study.
Xanthophyll Levels in Turfgrass Clippings1
Authors: Turgeon A. J. , Lester Gene 
Published: July 2010

AbstractXanthophylls include various plant pigments that are important in poultry diets for skin and yolk coloration. The recent use of turfgrass clippings as a source of xanthophyll for inclusion in poultry feed is a significant development since there are vast acreages of turf that could supply considerable amounts of clippings from routine mowing. The purpose of this study was to determine the xanthophyll levels in clippings from various turfgrass species and cultivars, and the effects of increasing nitrogen (N) fertilization on the xanthophyll concentration in the leaves.Clippings from 20 cultivars of Kentucky bluegrass (Poa pratensis L.), 4 of perennial ryegrass (Lolium perenne L.) and ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreb.) were analyzed for noneproxide xanthophyll (lutein). Levels ranges from 72 to 358 mg lutein per kg of clipping fresh weight depending upon species and cultivar. Increasing N fertilization resulted in significant but small lutein increases in Kentucky bluegrass clippings.
Downy Brome Control in Dryland Winter Wheat with Stubble‐mulch Fallow and Seeding Management1
Authors: Massee T. W. 
Published: July 2010

AbstractDifferences in downy brome (Bromus tectorum L.) control had been observed under field conditions of eastern Idaho when dates of stubble‐mulch tillage, final rod weeding, and winter wheat (Triticum aestivum L.) planting were varied. This field‐plot experiment on Tetonia silt loam (Pachic Cryoboroll‐coarse, silty, mixed) tested the degree of downy brome control obtained with three initial stubble‐mulch tillage dates, two final rod weeding dates, and three winter wheat planting dates.Downy brome was best controlled with a combination of initial tilling early in the spring and a final rod weeding just before the late (15 September) wheat planting date. The early tillage killed downy brome before they produced seed. This also resulted in sufficient soil moisture retention in the seed zone for fall germination of other downy brome seeds, which were then killed by the final rod weeding just before the late wheat planting.A reduction in natural downy brome emergence was observed at later fall dates. This was confirmed in a separate field‐plot experiment (Portneuf silt loam, Xerollic Calciorthid, coarse, silty, mixed) where downy brome seed was planted at several dates, and helped explain some of the benefits of the mentioned late rod weeding and planting treatment.These procedures incorporating stubble‐mulch fallow are recommended, as normally practiced moldboard plowing creates an erosion hazard.
Modification of a Grassland Drill for Sward Interseeding1
Authors: Smith A. E. , Calvert G. V. 
Published: July 2010

AbstractThe commercially available pasture seeders have been found to be ineffective in stoney and topographically uneven swards, incapable of seeding in row spacing widths of less than 44 cm or too expensive for the average pasture renovation system. Introducing additional species into an existing sward has been recognized as beneficial for increasing forage production and quality and seasonal distribution of forage production. This publication describes a modification of a John‐Deere grassland drill. This modified pasture drill has been effective for interseeding ladino clover (Trifolium repens L. var. Ladino) into established stands of tall fescue (Festuca arundinacea Schreb) in the Piedmont area of Georgia.
Digestibility of Four Digitgrass Cultivars under Different Harvest Frequencies1
Authors: Sleper D. A. , Mott G. O. 
Published: July 2010

AbstractLack of good forage quality is one of the factors limiting animal production on digitgrass pastures. The purpose of this investigation was to examine quality differences in digitgrass. Three digitgrass cultivars and an interspecific hybrid were used to determine cultivar differences and duration of regrowth period that would provide maximum in vitro digestibility for the summer. Forage was harvested at 14, 28, and 42‐day intervals. Forage harvested every 14 days had significantly higher digestibility than that harvested at 28 and 42‐day intervals. Cultivars also differed significantly in digestibility. ‘Transvala’ (Digitaria decumbens Stent.) had the highest in vitro digestibility when harvested at 14‐day intervals (70%) whereas an experimental interspecific hybrid X50‐1 (parents were Digitaria milanjiana Strent, and Digitaria Pentzii Stent.) had the highest digestibility of all cultivars at the 28 and 42‐day regrowth intervals (68 and 61%, respectively). Within the 14‐day harvest frequency, ‘Pangola’ (Digitaria decumbens Stent.) decreased in digestibility the most and ‘Slenderstem’ (Digitaria pentzii Stent.) the least as the season progressed. Management systems and breeding objectives that allow for improved quality in digitgrass should be utilized.
Cow and Calf Performance, per Hectare Productivity, and Persistence of Crownvetch under Grazing1
Authors: Burns J. C. , Cope W. A. , Barrick E. R. 
Published: July 2010

AbstractCrownvetch (Coronilla varia L.) has been observed to be somewhat less sensitive to midsummer stress in the Piedmont region of the Southeastern USA than other cool season legumes and has produced good ruminant daily gains. These factors suggest that crownvetch offers potential as a grazing forage, yet quantitative data on animal responses and stand persistence are lacking.The objective of this study were to further evaluate crownvetch as a grazing forage by considering cow and calf performance from pure stands as compared with that from tall fescue (Festuea arundinacea, Schreb. cv. ‘Ky 31’) and to determine the per hectare productivity [(total digestibue nutrients (TDN)], calf gain and animal days) and the persistence of crownvetch when continuously grazed.Calf daily gains (kg/head/day) from crownvetch averaged 0.96 for the two‐year evaluation phase compared with 0.67 from tall fescue (P ≤ 0.05). Cows grazing crownvetch also averaged 0.96 kg/head/day compared to 0.31 from tall fescue (P ≤ 0.05) with consistently higher average daily cow and calf gains from crownvetch throughout the grazing season.Crownvetch yielded 3,375 and 325 kg/ha of TDN and calf gain respectively, when stocked at 2.63 (season average) cow‐calf units/ha.By the end of the fourth year (spring 1972) crownvetch stand counts in the grazed paddocks were reduced 86%, as estimated from fixed points, or 89%, as estimated from random points. Crownvetch stands in plots fenced off and harvested mechanically (not grazed) after 2 years of grazing were reduced only 59% which is considerably less than that from continuous grazing.The animal‐gain data indicated that crownvetch is a very satisfactory forage for grazing. However, agronomically, crownvetch failed at this location when continuously grazed. Stands were extremely difficult to establish and were severely weakened at the end of the second grazing season. Before crownvetch can be agronnomically reliable for grazing in much of the Piedmont region, considerable effort must be given to increasing seedling vigor thereby aiding stand establishment and to develop more persistent plants to prolong stand survival.
Prediction of Late Season Nitrate‐Nitrogen Content of Sugarbeet Petioles1
Authors: Giles J. F. , Ludwick A. E. , Reuss J. O. 
Published: July 2010

AbstractNitrate nitrogen levels in sugarbeet (Beta vulgaris L.) petioles have been used as an aid to diagnose nutritional status of the plants. The purpose of this study was to evaluate a theoretical approach to the prediction of the rate of change in NO3‐N concentration of sugarbeet petioles. Petiole samples were collected from sugarbeet N fertilizer trials conducted over a 2‐year period on cooperator farm sites in central and eastern Colorado. Results showed the NO3‐N concentration of sugarbeet petioles through the growing season decreased exponentially. The rate of change was a function of soil NO3‐N content (0‐120 cm depth) measured in the spring and the amount of N applied as preplant fertilizer. Calculation of the rate of change with this function and the measurement of one early petiole sample enables the prediction of the NO3‐N concentration during the remainder of the growing season.
A Power Parabola for an Asymmetrical Response1
Authors: Adams Carol J. , Hills F. J. 
Published: July 2010

AbstractAs plant density increases, crop yield often increases, reaches a plateau, then decreases at a different rate. It is difficult to find a simple equation that will adequately describe this situation. A FORTRAN IV program is presented which can be used to fit a parabola to such an asymmetrical response by the transformation of abscissa and ordinate values to calculated powers, i.e. Yw = a + bXz + c(Xz)2. The procedure is illustrated with the response of sugar beet (Beta vulgaris L.) root yield to plant density in field plots and resulted in a power parabola of excellent fit (R2 = 0.955).
Effect of Increasing Foliage Reflectance on the CO2 Uptake and Transpiration Resistance of a Grain Sorghum Crop1
Authors: Moreshet S. , Stanhill G. , Fuchs M. 
Published: July 2010

AbstractThe investigation reported here was designed to provide a physiological explanation for the grain yield increases which resulted from whitening of dryland sorghum crop canopy (Sorghum bicolor L. Moench ‘Hazera 726’) by a kaolin suspension spray. Two years of field measurements of labelled CO2 uptake rates, on kaolin‐coated and uncoated sorghum leaves, showed that the kaolin coating caused a 23% decrease of net photosynthesis similar to the 26% reduction of solar radiation absorption measured with a spectrophotometer immediately after the spray. The reduction in net photosynthesis persisted for several weeks and was actually larger 6 weeks after the last kaolin application.Measurements of the dynamics of light dependent CO2 uptake made on leaves of different ages with a series of neutral filters and independent measurements of green leaf area confirmed enhanced senescence of the kaolin‐coated leaves.By contrast, field measurements with a diffusion porometer demonstrated only minor reductions in the leaf surface diffusion resistance of kaolin‐coated leaves.It is concluded that, for the sorghum crop examined, the primary effect of kaolin sprays was to reduce the rate of photosynthesis, both by decreased light absorption and by enhanced senescence. Finally, a possible explanation is offered to reconcile the reduction in photosynthesis with the observed increase in the grain yield of the treated crop.