bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Soil pH on Element Concentration and Uptake by Maize: II. Cu, B, Mn, Mo, Al, and Fe1
Authors: Lutz J. A. , Genter C. F. , Hawkins G. W. 
Published: July 2010

AbstractAn understanding of liming, fertilization, plant nutrition, and soil‐plant relationships requires a knowledge of the variability of element accumulation within the plant. The availability of micronutrients is related to soil pH. Except for Mo, the availability of micronutrients is believed to increase with increased acidity. Since many of the soils in the southeastern U. S. are acid, particularly the subsoil, additional information is needed on the growth, concentration, and uptake of elements by maize (Zea mays L.) as affected by soil pH.Selected maize inbreds and single crosses were grown in the greenhouse on Greendale silt loam that had been adjusted to pH levels of 3.9, 5.1, and 6.1 with appropriate amounts of pulverized dolomitic limestone. Adequate plant nutrients were applied. Maize was harvested 36 days after planting; dried; and later analyzed for Cu, B, Zn, Mn, Mo, Al, and Fe.Entries differed significantly in concentration of each analyzed element at one or more pH levels, thus showing differential absorption of specific elements at various pH levels. Soil pH had a highly significant effect on the concentration of all elements studied except Fe. The entry × pH interactions were significant only for B and Al concentrations.Entries differed in the uptake of all elements studied. Uptake of all elements except B was affected by pH, and entry × pH interactions were significant for each of the elements considered.
Soil Management Factors and Growth of Zea mays L. on Topsoil and Exposed Subsoil1
Authors: Batchelder A. R. , Jones J. N. 
Published: July 2010

AbstractExposed subsoils frequently are infertile and have low available water storage capacities. Corn (Zea mays L.) was grown for 4 years on a Groseclose clay loam surface soil and exposed clay subsoil to study the effects of selected management practices on subsoil productivity and the available water storage in exposed subsoils. Half of the exposed subsoil plots were covered with straw mulch, and half of all plots were irrigated. Lime was added the first 2 years and fertilizer was added each year to alleviate the growth‐limiting effects of low pH and low fertility.The treatments were reflected in surface water runoff from the 10 to 12% slopes, in soil water tension relation. ships, in plant growth, and in grain yields. Mulching reduced the surface water runoff, resulting in greater net water input. The soil water tensions to a depth of 45 on were generally lower under the straw mulch without irrigation than with either of the topsoil treatments.Top growth and grain yields generally increased on the subsoil treatments each year, and in the 4th year yields from the irrigated subsoil without mulch and both the irrigated and nonirrigated subsoil with mulch were equivalent to those of the irrigated topsoil, and significantly greater than those of topsoil without irrigation. In the last 2 years, when soil tests indicated that the low pH and low fertility had been mitigated, relative yields were markedly affected by the number of days during which the soil water tension at the 45‐cm depth exceeded 700 mb.
Effect of Planting Date on Sunflower Yield, Oil, and Plant Characteristics1
Authors: Johnson B. J. , Jellum M. D. 
Published: July 2010

AbstractPlanting date studies were conducted on sunflowers (Helianthus annuus L.) from 1969 through 1971 at Experiment, Ga. to evaluate the optimum time of planting on seed yield, oil percentage, oil composition, and other plant characteristics. Seeds of ‘Peredovik’ and ‘Krasnodarets’ varieties were planted at each date ranging from March 11 to July, 22.Highest seed yields and oil percentage of seeds were produced when sunflowers were planted from mid‐March through April. Fatty acid composition of seed oil varied considerably among planting dates within years as well as among similar planting dates between years. Other sunflower characteristics were not greatly affected except at the June or July plantings.
Phosphorus and Nitrate‐Nitrogen Immobilization by Wheat Straw1
Authors: Black A. L. , Reitz L. L. 
Published: July 2010

AbstractWith stubble‐mulch tillage systems, relatively large quantities of wheat straw with low N and P concentrations are being incorporated near seeding time in inherently P‐deficient soils of the northern Great Plains. This study was conducted to determine what additional adjustments in fertilizer applications might be necessary to compensate for the amount of N and P immobilized by known quantities of incorporated wheat straw under defined soil fertility levels.Wheat straw was incubated with four soils—Tally loamy sand, Dooley sandy loam, Williams clay loam, and Cherry silty clay. Straw was added at rates up to 10,000 ppm; and P, up to 260 ppm. The experiment was a randomized complete factorial design with three replications for soils, P rates, and straw rates. NaHCO3‐soluble P and nitrates were determined after seven alternate wet and dry incubation periods during a 60‐day period.Soluble P increased progressively as rate of P applied increased. Soluble P decreased progressively (P=.05) as straw rates increased. In all four soils, straw incorporation caused a much larger proportional decrease of soluble P at low than at high levels of applied P. The soil by straw treatment interaction was not significant (P=.05), indicating that incorporated straw rates had the same effect on soluble P in all soils. Soil nitrate mineralization was not significantly influenced (P=.05) by P rates even though the soils were P deficient. Nitrate levels decreased significantly as straw increased.
A Miniature Gravity‐Fed Thermocouple Psychrometer1
Authors: Mitchell S. T. , Kimball B. A. , Ehrler W. L. 
Published: July 2010

AbstractA miniature gravity‐fed thermocouple psychrometer was constructed and tested over a wide range of humidities and flow rates. The unit gave accurate wet bulb depression in 6‐mm flow tubes through an acrylic plastic block with a minimum flow rate of only 0.06 m/sec at 35% RH, and of only 0.09 m/sec at 11% RH.The psychrometer also agreed exactly with a standard psychrcmeter (Assmann type) in open air without forced ventilation or radiation shielding.
Effects of Nitrogen on Leaf Area Index, Leaf Area Duration, Net Assimilation Rate, and Yield of Wheat1
Authors: Khalifa M. A. 
Published: July 2010

AbstractThe low returns from nitrogen fertilization in central and eastern Sudan stimulated an investigation into the response of grain yields of irrigated wheat (Triticum aestivum L. em. Thell.) to two sources of nitrogen (ammonium sulfate and urea), two methods (broadcasting and sidedressing), and several times of application. Grain yields were unaffected by either source of nitrogen or by method of application. Application of the fertilizer at different stages of growth showed that the addition of fertilizer in the early phases of growth of the crop (at sowing or tillering) gave the greatest response. The response to application at ear emergence was much less. Splitting the nitrogen amount with half given at sowing and half at tillering or ear emergence had no extra merit, and a second application given early in the growing season had more effect on yields than a later one at ear emergence. Growth analysis indicated that the variation in grain yield was mainly a reflection of the effect of the treatments on the leaf area duration (LAD) after ear emergence. Early nitrogen application effectively increased LAD by increasing the leaf area index (LAI) toward the time of ear emergence, while late nitrogen had very little effect on LAI and consequently on LAD after ear emergence.
Broadcast or Banded Atrazine + Propachlor with Tillage Variables in Grain Sorghum1
Authors: Moomaw R. S. , Robison L. R. 
Published: July 2010

AbstractApplication of a herbicide to the least possible soil surface area consistent with adequate weed control in a given crop production system may be desirable because costs are reduced and less chemical is added to the environment. Data have not been available to indicate the minimum herbicide band width that could be used in combination with mechanical tillage in grain sorghum [Sorghum bicolor (L.) Moench] production. The herbicide mixture 2‐chloro‐4(ethylamino)‐6‐(isopropylamino)‐s‐triazine (atrazine) + 2‐chloro‐N‐isopropylacetanilide (propachlor) was applied preemergence broadcast and in herbicide band widths of 18, 36, and 53‐cm to grain sorghum. All herbicide treatments were applied as 1.1 kg atrazine + 2.7 kg propachlor per treated hectare. One row‐middle cultivation and one rotary hoeing were also imposed on the herbicide treatments as variables. The 18‐cm band of atrazine + propachlor with supplementary row‐middle cultivation was as effective in controlling weed growth and maintaining grain yield as were wider herbicide bands or a broadcast treatment. Broadcast herbicidetreated sorghum without cultivation yielded as well as the handweeded treatment both years of the experiment. Cultivation reduced average weed growth 73%. Cultivator effectiveness on an 18‐cm herbicide band equalled that measured on wider herbicide bands. Rotary hoeing significantly reduced weed growth and increased average grain yields 10% on herbicide‐treated plots. The average ratio of weed dry weight to reduction in grain sorghum yield was 1.3 to 1.
Evaluation of Herbicides for Use in Zero and Minimized Tilled Corn and Sorghum1
Authors: Robison L. R. , Wittmuss H. D. 
Published: July 2010

AbstractAdequate weed control has been one of the principal problems associated with developing minimized tillage systems. Recent herbicide releases appear promising for solving the weed control problem. We evaluated ten different preemergence herbicide treatments and one postemergence treatment for 3 years for weed control in till‐planted corn (Zea mays L.) and sorghum (Sorghum bicolor, L. Moench). All herbicide treatments were compared on plots that were either disked or nondisked to see if reduction of plant residues improved weed control. All herbicide treatments reduced weed populations and resulted in increased yields compared to the cultivated check. Plots that were disked as opposed to those nondisked were significantly lower in weed yields for 2 years, but were significantly better in crop yields only 1 year.Most of the herbicides gave excellent weed control even though residues of the previous year's crop averaged 5,218 kg/ha and covered 73% of the ground.
Effect of Supplemental Water on Barley and Corn Production in a Subhumid Region1
Authors: Power J. F. , Bond J. J. , Sellner W. A. , Olson H. M. 
Published: July 2010

AbstractA 3‐year field experiment was conducted on a loam soil in eastern North Dakota to determine the effect of supplemental water, added in various quantities and at different times, on malting barley (Hordeum vulgare, L.) and corn (Zea mays, L.) silage production. Irrigation consisted of (a) none; (b) after previous harvest only (to fill 120‐cm profile); (c) 6 cm applied per irrigation as needed during growing season; (d) after previous harvest plus 6 cm at anthesis; (e) after previous harvest plus 6 cm applied as needed during the growing season; and (f) after previous harvest plus 9 to 12 cm applied as needed during the growing season. Water added after harvest was not reflected in soil water content by seeding time the following spring or in increased crop yields, indicating that fall irrigation was of little value. A linear regression (r = 0.89) existed between total water use and both barley grain and corn silage production, with no distinct differences between the six water treatments evident. These results suggest that stored soil water, growing season precipitation, and added irrigation water are all equally effective in enhancing crop production, and within the range studied, one can be substituted for the other. The results also suggest that such factors as amount of water added per event and frequency or timing of events may be of less importance in subhumid than in more arid climates.
Manganese Nutrition of Cotton Under Two Boron Levels I. Growth and Development
Authors: Ohki Kenneth 
Published: July 2010

AbstractUpland cotton (Gossypium hirsutum L.) plants were grown in nutrient solution under greenhouse conditions to study manganese × boron interaction on cotton growth and development. A 2 × II factorial experiment included added B at 35 and 500 /ig B/I with eleven Mn rates from O to 4000 μg added Mn/1.The appearance of visible Mn deficiency symptoms preceded growth reduction indicating that growth rate processes are inhibited prior to visible deficiency manifestations. With very low Mn levels, only Mn deficiency symptoms existed at both B levels. As Mn levels increased slightly under low B, both B and Mn deficiency symptoms were simultaneously present, and at higher Mn levels where Mn supply was not limiting, only B deficiency symptoms occurred. Plant growth indicated by top weight was correlated with Mn and B deficiency symptoms.Manganese and B deficiencies retarded internodal growth without adversely influencing nodal development. Both Mn and B deficiencies reduced square development. The node of first fruiting branch was not affected by either B or Mn rates indicating no response to crop earliness.
Preplant Application of Herbicides for Weed Control in Grain Sorghum1
Authors: Wiese Allen F. , Chenault E. Wayne , Hollingsworth Dale 
Published: July 2010

AbstractAt the time these studies were initiated, there was no effective, safe method of applying herbicides prior to planting sorghum (Sorghum bicolor (L.) Moench). Over a 4‐year period, preplant application of herbicides at various times before planting and methods of herbicide incorporation were evaluated for control of pigweed (Amaranthus spp.) and barnyardgrass (Echinochloa crusgalli:(L.) Beauv). Effective preplant herbicides on clay loam soil were terbutryn (2‐(tert‐butylamino)‐4‐(ethylamino)‐6‐(methylthio)‐s‐triazine), propazine (2‐chloro‐4,6‐bis(isopropylamino)‐s‐triazine), and mixtures of propazine with either norea (3‐hexahydro‐4,7‐methanoindan‐5‐yl)‐l,l‐dimethylurea) or linuron (3‐(3,4‐dichlorophenyl)‐l‐methoxy‐l‐methylurea). In order to prevent crop injury and obtain weed control equal to or better than that obtained with preemergence application, the herbicides had to be applied to beds and incorporated with a rolling cultivator within 2 weeks prior to planting. Incorporation with a tandem disk before bedding resulted in crop injury.
Portable Reflectance Meter for Estimating Chlorophyll Concentrations in Leaves1
Authors: Wallihan E. F. 
Published: July 2010

AbstractThe need to measure changes of chlorophyll concentration in citrus leaves required a nondestructive method of analysis applicable to field use. Light reflectance in the wavelength region of 600 nm had been shown to be useful for this purpose but existing reflectance meters were too bulky for field use and generally required line power. The instrument described here is battery operated, compact, and measures light reflectance in a band of wavelengths from 610 nm to 700 nm from four miniature incandescent lamps. Arrangement of the light unit on a spring clamp permits readings in the field on several leaves per minute.Calibration against measured chlorophyll concentrations yields a log log curve revealing maximum sensitivity at low chlorophyll concentrations. Tests on leaves from iron‐deficient orange trees showed the coefficient of variability to be in the vicinity of ± 15%. By reading 20 replicate leaves, sampling errors were compensated sufficiently to give precision of about ± 3%.Major limitations observed were (1) interference from red pigments in young leaves and (2) variable readings from mottled leaves, depending on position of the sensor on the leaf.
Effect of a Killed Sod Mulch on Nitrate Movement and Corn Yield1
Authors: Thomas G. W. , Blevins R. L. , Phillips R. E. , McMahon R. L. 
Published: July 2010

AbstractCorn (Zea mays L.) was planted in a Maury silt loam soil under conventional tillage and in a chemically‐killed bluegrass (Poa pratensis L.) sod in 1970 and 1971 in order to determine the behavior of nitrate and the yield of corn under both cultural systems. Nitrate under both cultural treatments was sampled before and after June rainfall periods in both years. A large fraction of the nitrate was lost from the top 90 cm of soil under the killed‐sod plots, whereas, no nitrate was lost from the conventionally‐tilled plots. The loss of nitrate under the killed sod was attributed to two factors: 1) lower evaporation from the mulched soil; and 2) deep penetration of water and nitrate through larger pores in the wetter, mulched soil.Corn yields where nitrogen was applied tended to be higher on the killed‐sod plots in a dry year (1970) and about the same in a wet year (1971). However, the no nitrogen treatment on the mulched plots had a much lower yield than did the conventionally‐tilled no nitrogen treatment in the wet year of 1971. The results suggest that higher nitrogen rates may be required when corn is grown in a killed sod mulch as compared to conventionally‐tilled corn.
Comparative Lime Effects on Continuous No‐Tillage and Conventionally Tilled Corn1
Authors: Moschler W. W. , Martens D. C. , Rich C. I. , Shear G. M. 
Published: July 2010

AbstractBecause the absence of tillage precludes the mixing of lime with soil when no‐tillage corn (Zea mays L.) is grown, an experiment was conducted to determine if surface application would be effective. Information on the subject is not presently available but is needed to guide growers in neutralizing soil acidity caused by high rates of nitrogen applied to corn.Field studies over an 8‐year period compared continuous no‐tillage corn with surface‐applied lime to continuous conventionally tilled corn with lime incorporated into the soil. Comparisons of the two tillage methods were also made without lime to determine the degree of response to lime. Lime increased corn yield more than twice as much in no‐tillage culture as in conventional tillage. Lime was essential for highest yields with both tillage methods but the yield increase due to surface applied lime in no‐tillage culture averaged 31.3%, compared to a 13.5% yield increase due to incorporated, lime in conventional tillage culture.Associated with the larger yield increase from lime in the no‐tillage culture were 1) a higher pH in the 0 to 10‐cm soil layer (averaging 6.4 in no‐tillage compared to 6.0 in conventional tillage) in the eighth year; and 2) larger increase in exchangeable Ca and a reduction in exchangeable AI in the 0 to 10‐cm layer. The pH and exchangeable Ca and AI in the 10 to 20‐cm soil layers from tilled and nontilled soil were almost identical. A highly significant correlation was found between maturity of the corn and yield increase due to lime. Thus, it appears probable that the principal mechanism for the yield reduction caused by the lack of lime was reduced growth. This was especially apparent in early growth stages but was partially overcome later. It was more noticeable in no‐tillage corn than in conventionally tilled corn. At harvest, the increase in dry matter content of no‐tillage corn ears which was caused by lime was larger than that in conventionally tilled corn.Water use efficiency for the increased corn grain yield due to lime in no‐tillage was calculated to be almost three times that in conventional tillage.
Nutritive Value of Pensacola Bahiagrass Stolons1
Authors: Rodriguez M. , Blue W. G. , Moore J. E. 
Published: July 2010

AbstractForage shortage and low forage quality during the winter season are critical in Florida during some years. Pensacola bahiagrass (Paspalum notatum Flugge) produces massive stolon‐root systems with relatively high crude protein concentrations if adequate nutrients are supplied. Preliminary in vitro digestion studies with these stolons indicated high digestibility. An experiment was initiated to study the feed value of this material and to determine the feasibility of using it during critical winter periods. Stolon evaluation was made by chemical analyses and by feeding trials with sheep to determine voluntary intake and nutrient digestibilities. Chopped stolons were mixed with chopped bahiagrass hay to give variable hay:stolon ratios. Each ration was supplemented with 10% molasses and 10% soybean meal. Dry matter and crude protein contents for all rations were approximately 86 and 12.5%, respectively. No difference was found in intake of organic matter or digestible organic matter among treatments. Cellulose digestibility decreased as the proportion of stolons in the rations was increased, but crude protein digestibility increased. Animals on all treatments averaged gains in excess of 5 kg during the 21‐day period. The chopped stolons were not readily accepted by sheep, but the addition of molasses and soybean meal markedly improved palatability. Cattle withheld from feed for 2 days consumed the stolons satisfactorily.
Protein Content and Seed Size Relationships with Seedling Vigor of Wheat Cultivars1
Authors: Ries S. K. , Everson E. H. 
Published: July 2010

AbstractThe source of wheat (Triticum aestivum L.) seed may affect crop growth and yield. Within a genotype, seed that has a higher protein content and/or is larger will produce more vigorous seedlings and sometimes higher yields.Spring and winter wheat seed collected from five cultivar trials grown at several different locations were used to determine the relative effect of genotype and environment on seed protein and seed size, and these factors were related to the dry weight of seedling shoots (vigor).Both environment and genotype affected the protein content of the seed. Regardless of genotype or environment, seedling vigor was consistently related to seed protein. Seedling vigor was also related to seed size, but when seed size was eliminated as a factor by using uniformly sized seed, the seed protein content and vigor relationships were significant.
Rooting Density and Water Extraction Patterns for Corn (Zea mays L.)1
Authors: Taylor H. M. , Klepper Betty 
Published: July 2010

AbstractBecause they occur at greater distances from the plant stem, roots deep within the profile often are considered less effective than those near the soil surface.An experiment was conducted to compare water‐absorbing efficiency, per centimeter of root, of corn (Zea mays L.) roots deep in the profile with that of roots near the soil surface. Plants were grown in a rhizotron compartment with rainfall excluded by a metal cover over the soil. Soil water content was determined with a neutron probe; rooting density, from measurements of roots on the glass viewing surface of the compartment. Leaf area was calculated by a length‐width method and plant height was measured daily. Stomatal aperture was estimated with a pressure drop promoter twice daily.With few exceptions, soil water content decreased and rooting density increased during the experiment. For the first weeks, transpiration exceeded pan evaporation, but toward the end of the experiment it was about half as much as pan evaporation. Water uptake per centimeter of root was affected most by soil hydraulic, conductivity, and at a given conductivity, it was greater at lower root densities. This effect of root density probably occurred because the roots were younger and more permeable at low root densities than at high root densities. Thus, for the conditions of these experiments, roots deep in the profile were probably more effective per centimeter of root for water uptake than shallow roots because they were younger and were in wetter soil.