bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Soil Water Tension on the Emergence and Growth of Cotton Seedlings1
Authors: Jensen R. D. 
Published: July 2010

AbstractA laboratory study was conducted to determine the effects of soil water tension on the rate and percentage of emergence and the vigor of cotton (Gossypium hirsutum L.) seedlings in a soil environment. Pressure plate apparatus was used to bring the soil to the tensions desired. One hundred seeds were planted equal distance apart in a silt loam soil at a depth of 2.5 cm in a 30‐cm‐diameter enameled pan. The soil was compressed around the seeds to a bulk density of about 1.1 g/cm3. The pan was enclosed in a transparent plastic bag and placed in a constant temperature chamber at 25 C. The number, height, and a description of the appearance of the seedlings which had emerged were recorded daily for 4 weeks.Total emergence was not affected by changes in soil water tension between 1/3 bar and 3 bars. Emergence at 4 bars tension was significantly less than at lower tensions. The number of seedlings which emerged decreased slowly as the tension increased from 4 to 7.5 bars. A sharp decrease was observed in the emergence at a tension of 8 bars. No emergence occurred at tensions greater than 12 bars. The time required for emergence and the growth rate of seedlings was not significantly affected by changes in tension from 1/3 to 1 bar. The rate of emergence and the growth rate progressively decreased as tension increased from 2 to 4 bars. Thereafter, as tension increased, time requird for emergence increased rapidly and rate of growth simultaneously decreased sharply.
Influence of Nitrogen Nutrition and Suckering Practice on Content and Distribution of Certain Mineral Elements in Burley Tobacco1
Authors: Sims J. L. , Atkinson W. O. 
Published: July 2010

AbstractNicotiana tabacum L. cv. ‘Burley 21’ was grown in the field at Lexington, Ky., to determine the influence of N nutrition and suckering practices on concentration and distribution of principal mineral elements in different plant parts. Generally, total plant contents of K, Ca, Mg, and Mn all increased as the N fertilizer rate was increased from 112 to 224 kg N/ha, but increasing the rate to 448 kg N/ha provided no further increases in uptake with exception of Mn. The Mn content was nearly doubled by increasing the rate of N from 224 to 448 kg/ha. As an average of all treatments, total uptake of P, K, Ca, Mg, and Mn was 12, 211, 152, 26, and 0.8 kg/ha, respectively.Practices to control suckers (axillary buds) and tops (seed heads), as well as the harvest date, influenced both total uptake and distribution of mineral elements among plant parts. Total uptake decreased with increasing degree of sucker control and was least for plants treated with maleic hydrazide. Data for harvest date indicated that considerable redistribution of elements occurred among plant parts between harvest dates. Elements generally considered to have the greatest mobility in plants, e.g., P, K, and to a lesser extent Mg, were present in relatively high amounts in tops and suckers and in relatively low amounts in leaves. The reverse was true for Ca and Mn.
Growth and Water Potential of Root Crops as Influenced by Salinity and Relative Humidity1
Authors: Hoffman G. J. , Rawlins S. L. 
Published: July 2010

AbstractThe interaction of relative humidity and salinity on garden beet, onion, and radish was studied in sunlit climate chambers at temperatures cycling daily between 26 and 10 C. Average daytime relative humidity (RH) was controlled at 45 and 90%. The root medium of each crop was maintained at four different osmotic potentials, the range depending on the crop's salt tolerance.With a nonsaline root medium, increasing RH from 45 to 90% increased the yield of beet by 50% and radish by 15%, but did not enhance the yield of onion. In saline root media, high RH significantly raised the salinity level at which the yield was reduced to 50% of the nonsaline yield for onion and radish, but did not affect this level for beet.Linear relationships between leaf water (ΨL) and osmotic (πL) potentials and the osmotic potential of the root medium (πS) were found for all three crops. Except low values of πS (high salinity), ΨL and πL were lower at 45% RH than at 90% RH. Leaf turgor potential was not affected by salinity in beet and onion but was reduced in radish.The relationship between crop yield and ΨL was linear. The difference in ΨL for plants between full yield and almost no yield was only 13 bars for beet, 6 bars for radish, and 4 bars for onion.
Response of Corn to Residual and Applied Zinc as ZnSO4 and Zn‐EDTA in Field Investigations1
Authors: Schnappinger M. G. , Martens D. C. , Hawkins G. W. , Amos D. F. , McCart G. D. 
Published: July 2010

AbstractField investigations were conducted to evaluate the response of corn (Zea mays L.) to residual Zn in Litz silt loam and to determine the level of Zn required to correct Zn deficiency in corn on Westmoreland silty clay loam. Corn yields were increased on the Litz soil in 1969, where 7 and 14 kg Zn/ha as broadcast ZnSO4, and 4.4 kg Zn/ha as broadcast Zn‐EDTA were applied in 1968. A lower level of broadcast Zn‐EDTA of 2.2 kg Zn/ha was inadequate to increase yield. The residual Zn from application of 14 kg Zn/ha as ZnSO4 increased yield to a greater extent than residual Zn from application of 4.4 kg Zn/ha as Zn‐EDTA. Residual Zn from application of 7 kg Zn/ha as ZnSO4 was intermediate between these treatments in increasing yield. More than 13.6 kg Zn/ha as broadcast ZnSO4 was required to correct Zn deficiency of corn on a Westmoreland silty clay loam.
Yield Probabilities for Cotton and Grain Sorghum Grown Under Dryland Conditions on the Texas High Plains1
Authors: Bilbro J. D. 
Published: July 2010

AbstractYield probabilities were calculated for cotton (Gossypium hirsutum L.) and grain sorghum [Sorghum bicolor (L.) Moench] grown continuously and in rotations under dryland conditions on the Texas High Plains. The probabilities were calculated using the gamma function technique on data from three rotations (or cropping systems) of a 36‐year dryland study conducted at Lubbock, Texas during the period 1914‐1949. Differences in yields between rotations were also tested for statistical significance.The mean lint yield of the continuous‐cotton cropping system was 19 kg/ha greater than that of the cotton in the cotton and grain sorghum rotation, but this difference was not statistically significant. Also, the shape parameter estimates (“g” values) for these two rotations were the same. Therefore, calculated yield probabilities for them were essentially equal. Yields of dryland cotton should exceed 150, 250, 400, and 600 kg/ha approximately 30, 50, 25, and 10% of the time, respectively.The mean yield of grain sorghum grown in rotation with cotton was significantly higher than that from the continuous‐grain sorghum cropping system. Also, the “g” value obtained from the rotation was slightly higher than that obtained from the continuous‐grain sorghum cropping system. Therefore, the grain sorghum yield for a given probability level will be higher in rotations with cotton than from a continuous cropping system. A dryland, continuous‐grain sorghum cropping system should produce yields exceeding 750, 1,200, 2,000, and 2,750 kg/ha approximately 70, 50, 25, and 10% of the time, respectively. Slightly higher, yields can be expected when grain sorghum is grown m alternate years with cotton. Also, l0 to 20% higher dryland yields can be expected if hybrids are substituted for open‐pollinated varieties.
Yield Response of Pangolagrass Grown on Tiwiwid Fine Sand to Mg and Fritted Micronutrients1
Authors: Chesney H. A. D. 
Published: July 2010

AbstractWith the recent availability of 30,000 ha of Tiwiwid fine sand (Type Quartzipsamment), a highly leached, excessively permeable, coarse‐textured soil of poor natural fertility, it was necessary to evaluate the potential of this marginal soil for sustained agricultural production.The effect of Mg and Fritted micronutrients (FTE 503)—singly and in combination—on the dry matter yield of pangolagrass (Digitaria decumbens Stent) was studied over an 18‐month period by means of a 32 factorial experiment. The variables of Mg and FTE 503 were 0, 88, and 176 kg/ha/annum of MgO and FTE 503, respectively, applied in four equal increments at 12‐week intervals. Yields were measured by cutting the grass at regular intervals.Magnesiumd id not have a positive effect on yield at any harvest and actually depressed yields at some harvests. Magnesium ✕ micronutrients interaction was also non‐significant.Up to 88 kg/ha/annum of FTE 503 generally and 176 kg/ha/annum during periods of heavy rainfall increased yields at all harvests, with the effect becoming progressively greater with time. Some micronutrient deficiencies were observed on the grass that did not receive micronutrients. Over the 18‐month period FTE 503 increased total dry matter yield by 8,700 kg/ha over the control.
Missing Hills in Rice Experimental Plots1
Authors: Gomez K. A. , De Datta S. K. 
Published: July 2010

AbstractThe effects of missing hills on the performance of the surrounding plants were investigated in a series of rice (Oryza satlva L.) field experiments under several conditions. Plants immediately adjacent to a missing hill were found to have significantly more panicles and higher yield than plants surrounded by living hills. The magnitude of the increase, however, varied with variety, plant spacing, fertility level, crop season, and the number and the distribution of missing hills. The stand correction method is therefore not applicable to rice. To determine yields of plots wtih missing hills, only fully competitive plants should be harvested.
A New Approach to Phenological Research — Relationships Between Environmental Factors and Days to the Appearance of the First Leaf in Four Perennial Species1
Authors: Benacchio S. S. , Blair B. O. 
Published: July 2010

AbstractPlant‐climate‐soil relationships were studied during the years 1968 and 1969 on the basis of the phenological pattern of appearance of the first leaf in spring of four perennial species, spirea (Spirea spp L.), orchardgrass (Dactylis glomerata L.), fall aster (Aster azureus L.), and big blue stem (Andropogon gerardi L.). Plantings of these species were previously established in plots adjacent to official weather stations at all five locations in Indiana. Comparisons between the environmental factors and the appearance of the first leaf were made using two multiple regression analysis methods. First leaf appearance during the 2 years did not follow Hopkins' bioclimatic law at these locations. In a northern Indiana muck soil at Wanatah, the growing season began 6 to 10 days later in the 1969 year than on a sandy loam soil located only 250 m from that location. Appearance of the first leaf at all locations for the four species over both years was 2 or 3 weeks earlier at the southern location than on the heavier soils in central and northern Indiana. Regression analysis show that six parameters contributed to much of the R2 value, with each independently contributing to a high R2 value. The regression included those factors that would develop R2 values to .9000+. Parameters consistently contributing to this value were daylight hours and soil temperatures at 20, 5.0, and 2.5 cm (base OC bare soil).Daylight hours from the last frost to first leaf were the most consistent parameter correlated with appearance of the first leaf. Soil temperature at 20 cm was also important and contributed to increasing R2Soil differences, based on detailed physical and chemical analyses, accounted for plant response variation indirectly, especially as related to texture that influenced water‐holding capacity and subsequently temperature.This is an interesting parameter as it relates to soilplant‐climate interactions in heavy‐textured soils. The correlation for soil and air temperature relationship was linear. Degree‐day accumulation was different in the 2 years, indicating that other factors, such as the soil temperature‐moisture interaction, minutes of sunshine, net radiation, etc., may be important environmental parameters involved in initiation of plant growth in the spring as indicated by the appearance of the first leaf.
Subterranean Clover (Trifolium subterraneum L.) Yield and Nutrient Content as Influenced by Soil Molybdenum Status1
Authors: Dawson M. D. , Bhella H. S. 
Published: July 2010

AbstractExperiments were initiated to elucidate the effect of Mo application on subterranean clover with respect to yield and nutrient status and to examine an anion exchange resin as a means of assaying plant available Mo.Highly significant yield and relative total N uptake of subterranean clover (Trifolium subterraneum L.) were obtained following Mo fertilization in greenhouse studies and field trials conducted on hill soils of western Oregon. Generally greatest relative yield as well as relative total N uptake from applied Mo occurred at the lower anion exchangeable soil Mo levels. There was no significant change in plant Cu concentration following Mo fertilization. However, Mo treated soils produced clover somewhat higher in Mo concentration than untreated soils. Cu concentration in clover appeared sufficiently high relative to the Mo concentration to present little chance of nutritional disorders in ruminants.
Animal Preference and Utilization of Selected Forage Sorghums Grazed in Fall and Winter1
Authors: Rieck W. L. , Croy L. I. , Davies F. F. 
Published: July 2010

AbstractThis study was initiated to determine forage quality and animal utilization of eight forage sorghum types (Sorghum bicolor (L.) Moench.) in situ after frost. Planting date was late to insure that plants would be in the boot to bloom stage by killing frost thus providing high yields of medium to high quality forage.As winter progressed, the available forage, percent digestion, and percent utilization declined for all types. The protein content was not affected during the winter season, but the percent dry matter increased with time. ‘Sugar Drip’ was consistently higher in the amount of forage utilized, in vitro dry matter digestion, and moisture content throughout the winter. ‘Pioneer 931’ produced higher yields than any other type, but was not used as efficiently as some of the other types.The research indicated that it is feasible to graze cured forage sorghums for maintenance rations with reasonably low costs in areas where the winters permit.
A Miniature Strip Net Radiometer1
Authors: Harper Lowry A. 
Published: July 2010

AbstractAn inexpensive miniature strip net radiometer was constructed for average net radiation measurement along a horizontal line in dense foliage such as short grasses or row crops. The sensing surface was 1.3 ✕ 40 cm and was enclosed in a polyethylene shield for protection against wind and weather. The unit was calibrated relative to a temperature‐compensated, net‐exchange radiometer, and gave a linear response.
Variation of Soluble Phenolic Compounds in Flue‐cured Tobacco Cultivars with Stalk Position1
Authors: Andersen R. A. , Tso T. C. , Chaplin J. F. 
Published: July 2010

AbstractPhenolic levels in field‐grown flue‐cured leaves of ‘Coker 139,’ ‘NC 95,’ ‘SC 58,’ and ‘LN 38’ were compared within each cultivar according to leaf positions on the stalks and among the four cultivars. Each of the cultivars showed a significant but generally nonlinear increase in levels of total phenolics (about 2‐fold for each) and sums of chlorogenic acids and rutin (2 to 9‐fold depending on cultivar) with eight ascending leaf positions on the stalk from lower to upper leaves. However, mean values of total phenolic reducing power equivalent to a chlorogenic acid standard and averaged over all stalk positions ranged from 7.17% in Coker 139 to 7.92% in NC 95; these values were not significantly different among the cultivars. Likewise, means of the sums of chlorogenic acids and rutin averaged over all leaf positions on the stalk ranged from 120% in Coker 139 to 1.59% in NC 95, and the four cultivars were not significantly different. Total soluble phenolic compounds were estimated by their bonding to insoluble polyvinylpyrrolidone at pH 3.5. Chlorogenic acid isomers and rutin were determined by electron capture gas chromatographic analysis based upon the amount of soluble caffeic acid and quercetin moieties found. Leaf phenolic compounds affect color and quality and may contribute to the tumor‐promoting weak acid fraction of tobacco (Nicotiana tabacum L.) smoke condensate. Therefore, leaves of these cultivars from different positions on the stalk will be used for cigarette manufacture to correlate the phenolic‐stalk position findings with smoke characteristics and composition.
Plant Density Effect on Grain Yield of Corn Hybrids Diverse in Leaf Orientation1
Authors: Hicks D. R. , Stucker R. E. 
Published: July 2010

AbstractCorn (Zea mays L.) yields have increased when corn plant leaves are more vertically oriented compared to normal corn leaf habit, but there is little information on yield effect of plant density changes in corn genotypes that have erect leaf orientation. This work was conducted to evaluate the grain yield response to plant density of corn hybrids diverse in leaf orientation.Eighteen corn hybrids differing in leaf orientation were grown at five densities in 1969 and 1970. Data recorded were grain yield; ear moisture; and angle, width, and length of the leaf above the ear.In both years hybrids differed significantly for yield, leaf angle, leaf width, leaf length, and length to the breakpoint of the leaf above the ear and densities differed for yield, leaf angle, leaf width, and leaf length (1969 only). Yield and leaf angle (small angle characterizes uprightness) were negatively correlated at low populations; the correlation approached 0 as plant density increased.Hybrids were grouped on the basis of leaf angles and yield response to population in 1970. When groups differed in leaf angle, the linear regression coefficients of yield on density did not differ statistically. However, there was a statistical difference between linear regression coefficients, with no difference in mean leaf angles, when hybrids were grouped by yield response to population.
Effect of Day/Night Temperature on Seedling Establishment of Nicotiana tabacum L. in Controlled Environments1
Authors: Haroon Mohammed , Long R. C. , Weybrew J. A. 
Published: July 2010

AbstractThe trend toward mechanized planting or transplanting of tobacco necessitates that seedling establishment (germination and initial growth to the first leaf stage) occur rapidly, at a uniform rate, and at high percentage. The effect of nine day/night temperature combinations on seedling establishment of flue‐cured tobacco, Nicotiana tabacum L. ‘NC 2326,’ was studied under controlled conditions. Seeds were sown and germinated in temperature‐controlled greenhouses, and daily counts were made to determine the number of seedlings whose first leaf had emerged. Little difference in total seedling establishment (percentage) or in uniformity of rate (standard deviation of the mean days‐to‐establishment) was found between the 26/26, 26/22, 22/22, and 22/18 C day/night temperature treatments. The rates of seedling establishment (mean days‐to‐establishment) between most treatments were different. Day/night temperatures of 26/22 C resulted in the best overall response with respect to total, rate, and uniformity of rate of seedling establishment.
Expectations, Variances, and Sensitivity of Net Returns from Corn Fertilization Experiments1
Authors: Ogut Cevdet , Doll John P. , Kroth Earl M. , Colyer Dale 
Published: July 2010

AbstractMany experiments designed to provide data for estimating production response surfaces have been conducted for only one year and as a result, the findings were applicable to only one set of environmental conditions. To obtain more general results a series of experiments measuring corn (Zea mays L.) yield response to applied N and plant population were conducted at three locations for several years in northern Missouri. Expected profit functions were estimated for each experiment and the input amounts that would have maximized profits for the time period of the experiments were derived. The resulting amounts (expected optima) were 197 kg of N and 45,360 plants/ha for Grundy County, 140 kg of N and 40,488 plants for Saline County, and 135 kg of N and 34,455 plants in Boone County. These amounts were lower than many of the annual optima. Furthermore, expected profits over the experimental periods were relatively insensitive to departures from the annual optima. Additional analyses determined input rates that (i) minimized the cost or (ii) minimized the variance of a fixed expected profit level for the period. Expected profits from many of the annual optima could have been produced at substantially lower cost. Compared to cost minimization, variance minimization increased N and reduced stand; although N is more expensive than plant population, it “costs less” in terms of variance. Expected profits were quite sensitive to corn price and, to a lesser degree, N price; optimal inputs were much less sensitive to these same prices.
Nitrate‐N Accumulation in the Soil Profile Under Alfalfa1
Authors: Schertz David L. , Miller D. A. 
Published: July 2010

AbstractA study was conducted to determine the influence of various levels of ammonium nitrate applications of NO3‐‐N accumulations under alfalfa (Medicago sativa) and whether alfalfa has the ability to utilize excessive amounts of nitrate in the soil. Eight split applications of N totaling 0, 224, 448, and 672 kg/ha (0, 200, 400, and 600 pounds/acre) were studied at the Agronomy South Farm, Urbana, Ill. at various depths on six sampling dates. Soil was sampled at depths of O to 15, 15 to 30, 30 to 60, 60 to 90, and 90 to 105 cm or to the water table, which was never lower than 105 cm. Soil samples were dried, finely ground, and analyzed for NO3‐‐N. NO3‐‐N concentrations were greatest in March 1970 at the 30‐ to 60‐cm depth. No more than 1 ppm was found at the 90‐ to 105‐cm depth (water table) for any N treatments on Nov. 11, 1970. Highest concentrations of NO3‐‐N were found at the 15‐ to 30‐cm depth for all N treatments at the end of the growing season, Nov. 11. Although total amounts of NO3‐‐N were lower in March than in November, the highest accumulations were found at the 30‐ to 60‐cm depth in March, but at the 15‐ to 30‐cm depth in November. The only treatment on Nov. 11 that did not show a significant difference when compared to the check was the 224 kg N/ha. Alfalfa would have some value in a rotation for reducing NO3‐‐N, which may accumulate under continuous corn (Zea mays L.) after excessive N applications.
Response of Irrigated Corn to Time, Rate, and Source of Applied N on Sandy Soils1
Authors: Jung P. E. , Peterson L. A. , Schrader L. E. 
Published: July 2010

AbstractTo maximize N recovery by corn (Zea mays L.) on irrigated sandy soils, establishing the proper time for and rate of N application are essential. Three sources of N (urea, NH4,NO3, and KNO3) were applied to corn at four rates (56, 112, 168, and 224 kg/ha of N) and six times application in all combinations. ‘Wisconsin 273’ (85 R.M.) and ‘Wisconsin 433’ (95 R.M.) were grown. Response was measured as grain yield, tissue yield (aerial portion at early dent), percentage N in tissue, percentage N in grain, and N uptake The N applied during either the 5th, 6th, 7th, or 8th week after planting was the most effective as shown by increased grain and tissue yields. Nitrogen applied after the 8th week was associated with a distinct reduction in N uptake and grain and tissue yields. Generally, percentage N in the grain and tissue increased with later N applications. The responses to urea and NH4NO3 were similar and both sources were sig~fificantly better than KNO3. Nitrate reductase (NR) activity in the leaves and percentage N in grain and tissue increased with increasing rate of applied N. Yields of grain and tissue for Wisconsin 273 and Wisconsin 433 leveled off at the 112 and 168 kg/ha rates of N, respectively.