bluuebunny/crossref_metadata_2025_split huggingface dataset:
Yield of Dryland Grain Sorghum as Affected by Antitranspirant, Nitrogen, and Contributing Micro‐watershed1
Authors: Fuehring H. D. 
Published: July 2010

AbstractIn the semi‐arid Great Plains yields of grain sorghum [Sorghum bicolor (L.) Moench] are almost always limited by lack of rainfall or soil moisture during some part of the growing season. The purpose of this study was to determine if minimal land shaping practices in combination with antitranspirant application would increase yield levels of dryland grain sorghum.Variables were width of watershed, width of growing bed, applied N, and foliarly applied antitranspirant combined in a central composite experimental design. Use of contoured, compacted bare micro‐watersheds increased grain sorghum yields of adjacent growing beds considerably even in two relatively wet years. However, yields of the entire area (growing bed plus watershed) decreased. Atrazine (2‐chloro‐ethylamino‐6‐isopropylamino‐s‐triazine) as an antitranspirant at 0.2 to 0.3 kg/ha effectively increased sorghum grain yields under conditions of solid planting and adequate nitrogen. The antitranspirant‐nitrogen interaction was especially positive under conditions of moisture stress.Since most grain sorghum is grown under conditions where moisture stress is likely, further work on the use of antitranspirants is warranted in order to establish the conditions of response.
Critical Level of Mg in Western Nigerian Soils as Estimated under Greenhouse Conditions1
Authors: Lombin L. G. , Fayemi A. A. A. 
Published: July 2010

AbstractWidespread Mg deficiencies have not been reported in western Nigeria. But with continuous intensive cultivation, heavier fertilization especially with K, and the introduction of high yielding, responsive crop varieties Mg deficiency is likely to become a serious problem in the near future. Knowledge of the critical available Mg levels can be useful in conjunction with routine soil analysis data to monitor the onset of these deficiencies.There is no previously published work on Nigerian soils that estimated the available Mg level below which response to Mg fertilization can be expected. The objective of this investigation therefore was to approximate this critical level under greenhouse conditions.Twenty‐three Nigerian soils collected from various ecological zones and soil types were cropped to maize (Zea mays L.) in the greenhouse with and without Mg application. The maize tops were cut after 35 days, dried, weighed, milled, and analyzed for Mg. Using the dry matter weights relative yields were worked out for all the soils and the new Cate‐Nelson (6) statistical procedure used to estimate the critical level. This procedure involved a step‐wise splitting of the data into two groups using successive tentative critical levels to determine the level which maximized the overall predictive ability (R2) with the means of the two groups serving as the predictor values. An approximate critical level of 0.28 to 0.35 meq/100 g was obtained by this technique.Tests on individual plot yields showed that 0.28 meg/100 g neutral N NH4OAc, extractable Mg was low enough for statistically signficant response to Mg application. All soils (except no. 10) that had less than 5% saturation of CEC responded to Mg application; those with more than 7% Mg saturation did not respond to Mg.Mg deficiency symptoms were associated with soil Mg level of 0.17 meq/100 g or lower prior to planting and with plant Mg content of less than 0.1%. Although the critical level of available Mg approximated in this study (0.28 to 0.35 meq/100 g) is much lower than the average available Mg content (1.2 to 1.5 meq/100 g) of western Nigerian soils. Caution is nonetheless needed in evaluating the findings of the present study as greenhouse results may not necessarily reflect the true situations in the field.
Cultivar Blends in Safflower1
Authors: Abel George H. 
Published: July 2010

AbstractCultivar blends of safflower (Carthamus tinctorius L.) were evaluated to determine if there were any favorable competitive interactions for yield of seed or oil.In a 50:50 blend of ‘Gila’ and ‘12417’ there was an average over‐compensation of 3.6% for seed yield and 3.9% for oil yield. For a 50:50 blend of ‘Dart’ and ‘1415430’ there was undercompensation for both seed and oil yield in the 1 year of testing. Generally, seed and oil yield of the blends did not exceed that of the better cultivar planted alone.
Yield and Composition of Soybean Seed as Affected by N and S Fertilization1
Authors: Ham G. E. , Liener I. E. , Evans S. D. , Frazier R. D. , Nelson W. W. 
Published: July 2010

AbstractSoybeans (Glycine max (L.) Merr.) obtain nitrogen from soil and from symbiotic fixation when nodulated with effective strains of rhizobia. These two sources of N may need to be supplemented with fertilizer N for maximum seed yields. The objectives of the present study were to determine the effects of N and sulfur fertilization on soybean seed yield and other seed properties (protein, oil, amino acid, fatty acid, and S composition).Chippewa 64 and a nodulating‐nonnodulating (nodnonnod) pair of isolines of Chippewa background were examined at three field locations over 2 years for yield response to different forms of fertilizer N (224 kg/ha) and to fertilizer S (224 kg/ha). Three readily available fertilizers (ammonium nitrate, urea, and urea + sulfur) and two slow release fertilizer (S‐coated urea and ureaformaldehyde) were mixed in the top 20 cm of soil before planting. The soils were Nicollet silty clay loam (Aquic Hapludoll), McIntosh silt loam (Aeric Calciaquoll) and Webster clay loam (Typic Haplaquoll).Response to N fertilizer was greater with the nonnod isoline than with the other two lines. Nitrogen fertilization increased seed yield, weight per seed, seed protein percentage, and kg protein/ha. Plant height and lodging were either increased or unaffected, depending upon locations and/or year. Seed oil percentage decreased following N fertilization. However, total oil production usually increased due to larger yields. All sources of fertilizer decreased N2 fixation, plant nodule weight, nodule number, and weight per nodule.Amino acids increased uniformly with protein increases but fatty acid composition was unchanged.Sulfur fertilizer increased seed yield in one case and decreased seed yield in two cases depending on location and year. Total S percentage of the seed and S‐containing amino acids of the seed were not increased with S additions.Increases in seed yield and/or seed protein percentage in the nodulating lines suggest N2 fixation failed to supply amounts of N essential for maximum seed yield and/or protein percentage. With the recent concern for energy, N2 fixation must be increased to provide the N needed for maximum seed yields of soybeans rather than relying on fertilizer N.
Factors Affecting the Development of Flue‐cured Tobacco Grown in Artificial Environments. V. Effects of Humidity and Nitrogen Nutrition1
Authors: Raper C. David , Smith W. Tony 
Published: July 2010

AbstractControlled environment rooms (CERs) were used to investigate effects of relative humidity on physical and chemical properties of mature, flue‐cured tobacco (Nicotiana tabacum L.) leaves. The relative humidities in separate CERs were monitored with a dewpoint hygrometer and maintained at 90% (high) or 65% (low) relative humidity. Plants were moved between the two CERs to evaluate effects of diurnal and seasonal variations in relative humidity. The apparent effects of humidity on leaf size and shape were dependent on age of the plants. For plants grown in continuous high humidity, leaf sizes were greater at lower and middle stalk positions, but were less at upper stalk positions, than for plants grown in continuous low humidity. The reduction of areas of upper leaves by high humidity was a residual response to the humidity during the initial 3 to 5 weeks after transplanting. Initial periods of high humidity, whether followed by low or high humidity, also resulted in abnormally elongated upper leaves. Furthermore, variations in total plant leaf areas which resulted from diurnal variations in humidity were highly correlated with total nitrogen content in leaf tissues. These results suggest that suppression of nitrogen uptake by high humidity during a critical period of leaf formation was directly involved. Humidity during later stages of growth apparently has effects on the chemical balance within tobacco plants unassociated with nitrogen accumulation. High humidity during the light period tended to increase both starch and alkaloid composition of leaves.
Degradation of Alachlor by Rhizoctonia solani1
Authors: Smith A. E. , Phillips D. V. 
Published: July 2010

AbstractThe direct effects of herbicides on fungi are reported to include: inhibition, stimulation, or no effect as determinated by growth, sporulation, spore germination, and pathogenicity. Also, certain fungi have been found to rapidly degrade herbicides present in the ecosystem. Research was conducted to determine the influence of 2‐chloro‐2′,2′‐diethyl‐N‐(methoxymethyl)acetanilide (alachlor) on the growth and development of Rhizoctonia solani Kuehn, and to quantify the rate of alachlor degradation by R. solani in nutrient media containing differing concentrations of sucrose. Alachlor did not influence sugar utilization or growth of R. solani. Fungal growth and degree of alachlor degradation were proportional to the amount of sugar in the media. Apparently R. solani does not utilize alachlor as a sole carbon source and degradation of this herbicide is dependent on the presence of some other source of carbon.
Relationship of Exchangeable Acidity to Yield and Chemical Composition of Alfalfa1
Authors: Janghorbani M. , Roberts S. , Jackson T. L. 
Published: July 2010

AbstractThis study was undertaken to help clarify the soil acidity‐plant response relationship in western Oregon in an effort to improve the efficiency in the use of lime and fertilizer. The objective of the study was to relate the lime and P response of ‘Du Puits’ alfalfa (Medicago sativa L.) to selected measures of soil exchange acidity and exchangeable Al and Mn.Extractable acidity in soil samples from the A horizon of six representative soil series ranged from 0.3 to 8.1 meq/100 g of soil with a range of 0.2 to 7.9 meq/100 g exchangeable Al and somewhat lower amounts of Mn in the extracts.Responses of alfalfa to applied lime and P treatment combinations in greenhouse experiments were recorded for five of the six soil series studied. Maximum yield response was obtained with applications of either 4 or 8 meq of lime per 100 g of soil which largely eliminated KCl exchangeable acidity and Al at approximately pH 6.0 or higher. There was evidence of lime × P interactions on those soils that were both strongly acid and low in P with lime treatments increasing the availability of soil P. Lime application decreased tissue concentrations of Al and Mn, but increased plant Ca and P.It was concluded that the presence of exchange acidity and Al in the soils was indicative of a potential yield response to lime. The relatively large liming increments used in the study were not conducive to evaluating the precise amount of lime needed to react with a specified amount of exchange acidity or Al. The greatest benefit was derived from liming increments sufficient to neutralize the exchange acidity.
15N‐Labelled Single‐treatment Fertility Experiments1
Authors: Fried M. , Soper R. J. , Broeshart H. 
Published: July 2010

AbstractThere is only one way of measuring directly the uptake of nutrient from applied fertilizer as affected by timing, placement, fertilizer source, and environmental interactions. This is by isotope labelling of the fertilizer. The purpose of the present study is not only to demonstrate the effectiveness of this technique in field experiments, but to extend the technique to the direct measurement of these fertilizer efficiencies without interactions. A further extension permits the direct quantitative measurement of interactions.The method has been referred to as “single‐treatment fertility experiments” because all treatments, as far as the plant soil or environment are concerned, are identical. The only difference is which of the fertilizer applications within a given treatment was isotopically labelled. Thus growth, nutrient uptake, amount, and pattern in all plots is identical within normal experimental variation. The presence of the label permits the quantitative measure of treatment effects without interaction.The method has been successfully used in field experiments in various areas of the world with rice (Oryza sativa L.), maize (Zea mays L.), and wheat (Triticum aestivum L.), Problems quantitatively evaluated were: the relative effectiveness of NH4+ and NO3− as a source of N to rice at different placements; the effect of NH4+‐N in the fertilizer band on the uptake of P and of P on the uptake of NH4‐N; and the uptake of fertilizer N by corn, rice, and wheat as related to growth stage at which it was applied. Interactions can be directly and quantitatively measured by adding additional treatments.
Phosphorus Efficiency as Related to Iron Inefficiency in Sorghum
Authors: Brown J. C. , Jones W. E. 
Published: July 2010

AbstractSorghum (Sorghum bicolor L. Moench) is often grown on alkaline soils, and the plants frequently develop symptoms of Fe deficiency. The susceptibility is dependent on the ability of the plant to respond to Fe stress. This adaptive response is genetically controlled whereby H+ ions and a reductant are released from the roots. These make Fe available for uptake by the plant. Activation is greatest in Fe‐efficient plants and least in Fe‐inefficient plants. Phosphate accumulation and Fe‐stress response oppose each other in plant use of Fe. In this study, accumulation of phosphate and Fe‐stress response were evaluated as causes of Fe chlorosis in four sorghum cultivars that differ in uptake of P and in susceptibility to Fe chlorosis. The seedlings were first grown in a light chamber on a complete nutrient solution at, pH 4.3 until the plants were large enough for use. They were then transferred to nutrient solutions with Fe, P, NH4‐N or NO3‐N as variables. The pH of the nutrient solution, reductant in nutrient solution, and uptake of Fe and P by the plant were determined. The Fe‐efficient KS5 and ‘Pioneer 846’ sorghums released more reductant from their roots, took up more Fe, and contained less P than the Fe‐inefficient “B‐line” and ‘Wheatland’ cultivars. The release of H+ ions by roots was somewhat comparable in all four sorghum lines. On Bladen soil (pH 4.3—high in Al), KS5 and Pioneer 846 took up less P than the “B‐line” and Wheatland sorghum. Phosphorus efficiency in the four cultivars is “B‐line” ≥ Wheatland > Pioneer‐846 > KS5. In addition, KS5 developed iron chlorosis, which implies that KS5 cannot utilize either P or Fe in Bladen soil. Accumulation of P and insufficient Fe‐stress response both appear to be causative factors of Fe deficiency in “B‐line” and Wheatland sorghum.
Seasonal Development of, and the Effect of Inter‐plant Competition on, Soybean Nodules1
Authors: Weil R. R. , Ohlrogge A. J. 
Published: July 2010

AbstractResearch suggests that competition for photosynthate between nodules and seeds of soybeans [Glycine max (L.) Merr.] may be responsible for the apparent decline in symbiotic nitrogen fixation during the high N requirement pod‐filling period. A study was conducted in eight highly productive commercial fields to characterize the development of nodules during the growing season and to determine the effect on nodulation of thinning to one plant/m2 at a time (end of flowering period) when the response by the reproductive sink would be limited to a small increase in seed size.The number and size of nodules increased rapidly during flowering, peaked in early pod‐filling, and declined thereafter. After flowering, the percentage of red nodulated declined while the percentage of green (inactive) nodules increased. Total nodule volume/plant and active (i.e., red) nodule volume/plant peaked in mid‐August and then dropped off rapidly.The thinned plants showed significantly more nodule volume/plant, a greater percentage of red nodules, and a lower percentage of green nodules during pod‐filling, than did the plants growing at normal population densities. During that period, the thinned plants had 2 to 5 times as much active nodule volume/plant. The thinning treatment apparently postponed the decline in the nodules for several weeks. This effect was probably due to an increased supply of photosynthate available to the nodules at the lower plant density.
Effect of Soil and Foliar‐applied Manganese on the Micronutrient Content and Yield of Soybeans1
Authors: Randall G. W. , Schulte E. E. , Corey R. B. 
Published: July 2010

AbstractManganese deficiency of soybeans (Glycine max (L.) Merr.) will undoubtedly become more prevalent as soybean acreage increases along with strong emphasis on yield maximization. Thus, field experiments were conducted on two soils (Argiaquoll and a Hapludoll) in southern Wisconsin to evaluate sources, rates, and methods of application of Mn fertilizers on soybeans. Two sources, MnSO4 and Mn‐ethylenediaminetetraacetic acid (MnEDTA), were broadcast, row or foliar‐applied at various rates to Mn‐deficient soils and/or soybeans. Micronutrient concentrations, Mn uptake, and various production parameters were measured.All rates and application methods of MnSO4 and foliar applications of Mn‐EDTA were effective in supplying Mn to the plant. Row applications of MnSO4 were somewhat more efficient than broadcast applications. Manganese applied at rates ranging from 5 to 22 kg Mn/ha as MnSO4 with the starter fertilizer in the row at planting time appeared to be most efficient soil treatments in increasing seed yields. The MnEDTA applied in the row reduced plant weight, leaf Mn, and soybean yields slightly. When Zn was not included in the starter fertilizer, leaf Zn and Cu were increased by the soil‐applied MnEDTA treatments. Leaf Fe was not affected by any of the Mn treatments.Foliar applications of Mn were most effective when applied at the early blossom or early pod set stages or in multiple applications at these stages. Single applications of 2.24 and 4.48 kg Mn/ha as MnSO4 or 0.51 kg Mn/ha as MnEDTA caused some burning of the foliage.Combined row and foliar methods of application also appeared to relieve Mn deficiency effectively. Small amounts of MnSO4 applied in the row corrected the Mn deficiency early in the season, whereas foliar applications adequately supplied Mn to the plant later in the growing season. This combination resulted in higher yields than with either row or foliar treatments applied alone.
Effect of Irrigation, Lime, and Fertility Treatments on the Yield and Chemical Composition of Soybeans1
Authors: Lutz J. A. , Jones G. D. 
Published: July 2010

AbstractData are available on the effects of surface applied plant nutrients on the yield, quality, oil, and protein contents of soybean [Glycine max (L.) Merr.] seed and on the chemical composition of the soybean leaves. Very little information is available, however, on the effects of irrigation and plow sole (30.5 cm) placement of plant nutrients on these same plant characteristics.In order to determine the effects of irrigation and plow sole placement of P, K, lime, and micronutrients on the quality, yield, oil, and protein contents of soybean seeds and on the chemical composition of the leaves, a field experiment was conducted for 3 consecutive years. The experiment was located on Davidson clay loam (Rhodic Paleudults; clayey, kalonitic, thermic) at Orange, Va. Treatments included zero and 22.4 metric tons/ha lime, 336 and 672 kg/ha of EsMinel, and varying rates and ratios of P and K. The plowsole treatments were applied only when the experiment was initiated. The annual surface treatments on all plots have been 49 kg P/ha and 186 kgk/ha.Soybean seed yields were increased each year with irrigation; the average annual increase being 514 kg/ha or 22%. Yields were unaffected by P and K treatments during the first 2 years, but in the third year, yields were lower where P and K had not been applied on the plow sole. Lime and micronutrients did not significantly affect soybean seed yields.Irrigation increased the oil content each year but did not affect the protein content. Leaf P and K concentration were unaffected by irrigation but were affected by P and K applications. Leaf P concentration in 1972 and 1973 and K concentrations in 1972 were generally increased with increased rates of applied P and K respectively. Leaf Ca and Mg concentrations were increased with irrigation in 1971 but not in the other 2 years.Irrigation had no real effect on the amounts of available P, K, Ca, and Mg in the soil. The total amounts of these elements increased with increased rate of application. Applied lime did not affect the acidity below the 30‐cm depth.
Effects of Uneven Spreading of Fertilizer on Crop Yields1
Authors: Lutz J. A. , Jones G. D. , Hawkins G. W. , Hutcheson T. B. 
Published: July 2010

AbstractBulk spreading of fertilizer does not always result in a uniform distribution over the entire area. The extent to which this distribution affects crop yield is unknown and should be investigated. As a result, nine experiments were conducted over a period of several years to determine the effects of uneven distribution of fertilizer on the yield of corn (Zea mays L.), barley (Hordeum vulgare L.), soybeans (Glycine max L.), and wheat (Triticum aestivum L.). The investigations were conducted in the three physiographic areas of Virginia (i.e., mountain, piedmont, and coastal plain). Soil types varied from thich surface phase sandy loams to a clay loam. Four spread patterns commonly obtained in farming operations and a no‐fertilizer treatment were used.In 1970, corn on Frederick silt loam and Tatum silt loam responded to fertilization, but there was no significant differences among spread patterns on Lodi loam. Significant differences in yields among spread patterns on Davidson clay loam were observed. In 1971 there was an excellent barley response to fertilizer on Norfolk sandy loam, thick surface phase, and on Davidson clay loam, but no yield differences among spread patterns. Soybeans did not respond to fertilization on Davidson clay loam. Differences in corn yields among spread patterns on Nason silt loam were significant. Corn in 1972 on Groseclose silt loam and on Norfolk sandy loam, thick surface phase, did not respond to fertilization and hence there were no differences in yields among spread patterns. Differences in crop yields within spread patterns were observed on most of the soils.
Availability of Water Absorbed by Hardwood Bark Soil Amendment1
Authors: Spomer L. Art 
Published: July 2010

AbstractThis laboratory investigation determined the ‘availability’ of water absorbed by hardwood bark soil amendment. Water retention isotherms on a volumetric basis were determined on bark samples of seven different species (Fraxinus americana L., Populus deltioides Bartr., Acer rubrum L., Quercus rubra L., Platanus occidentalis L., Juglans nigra L., and Quercus alba L.) with a water pycnometer and a thermocouple psychrometer. Available water was assumed to be the volume held between 0 and −15 bars water potential. Maximum bark water content averaged about 40% of its wet volume; however, less than 25% of this water is released at water potentials between 0 and −15 bars. Hence, about three‐fourths of the water absorbed by bark is unavailable to plants.