bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cumulative Effects of Cutting Management on Forage Yields and Tiller Densities of Tall Fescue and Orchardgrass1
Authors: Hart Richard H. , Carlson G. E. , McCloud D. E. 
Published: July 2010

AbstractWhen tall fescue (Festuca arundinacea Schreb.) and orchardgrass (Dactylis glomerata L.) were cut each week after the first harvest, forage yields before flowering increased when first harvest was delayed and decreased as stubble height increased. Neither stubble height nor time of first harvest affected yields after flowering in the 1st harvest year. In the 2nd and 3rd years, yields after flowering decreased as stubble height increased. In the 3rd year they also decreased when the first harvest was delayed, so much that total forage yields were similar for all dates of first harvest, even though preflowering yields differed. The decrease in post‐flowering yield was associated with a decrease in stand density. Although increased stubble height decreased total forage yields, it increased yields of forage plus stubble, indicating higher total dry‐matter production. However, production was still higher when the grasses were cut closely every month instead of every week. This treatment gave the maximum forage production, because less of the total production was left as stubble.
Rooting of Poa annua L., Poa pratensis L., and Agrostis palustris Huds. at Three Soil Bulk Densities1
Authors: Wilkinson James F. , Duff D. Thomas 
Published: July 2010

AbstractPoa annua L. is usually considered an inherently shallow‐rooted grass. A growth‐chamber study was designed to compare the rooting of P. annua, P. pratensis L., and A. palustris Huds. at bulk densities of 1.1, 1.25, and 1.4. Treatments included P. annua and P. pratensis cut at 3.8 cm, and P. annua and A. palustris cut at 1.3 cm. Root samples were taken at four depths, 8 and 12 weeks after germination. Root weight was determined by weight loss after ashing the samples.Root weight decreased with depth, but increased with bulk density. Although root weight increased after 12 weeks, there was no significant difference between dates. When grown at the same bulk density, the root growth of all grasses was statistically the same at any given depth.
Effect of Transplanting and Plastic Cover on Growth of Sugar Beets1
Authors: Dillon M. A. , McCaslin B. D. , Schmehl W. R. 
Published: July 2010

AbstractTwo field experiments were conducted to determine the effect of transplanting and plastic cover on the seasonal growth and yield of sugar beets (Beta vulgaris L.). Both transplanting and plastic cover increased leaf areas in June and early July and increased final root yields. Earlier planting also increased early leaf areas and final root yields. The results showed that treatments increasing leaf area in June and early July increased final root yields, but differences in leaf area that occurred in August or later were not associated with differences in yields. Transplanting or plastic cover increased recoverable sucrose production as much as 44 to 48% over the conventionally planted sugar beets in 1968 and 26 to 27% in 1969. The advantages of these practices were greater for April than for May plantings.
Effects of Increasing Amounts of Organic Residues on Continuous Corn: I. Yields and Soil Physical Properties1
Authors: Morachan Y. B. , Moldenhauer W. C. , Larson W. E. 
Published: July 2010

AbstractWhen well‐fertilized corn (Zea mays L.) monocultures with large amounts of residues returned to the soil became common, the question was asked as to whether soil tilth and corn yields could be maintained at satisfactory levels in Corn Belt soils. To answer this question corn growth and soil physical properties were determined in a field experiment in which different types (alfalfa (Medicago sativa L.), cornstalks, sawdust, oatstraw (Avena sativa L.) and bromegrass (Bromus inermis Leyss)) and amounts (from 0 to 16 tons/ha/yr) of plant residues were added to Marshall silty clay loam (Typic Hapludoll) for 13 consecutive years. The soil was cropped to corn and large amounts of N were added. For approximately the first 9 years grain yields were lower from the check and sawdust treatments than from all others. During the last 4 years grain yields declined sharply with rate of addition of cornstalk residues and slightly from additions of alfalfa. It is suggested that the yield decline in the cornstalk treatments was due to a lowering of pH and an Al‐induced Ca deficiency in the plant. An alternative explanation is that the cation balance was upset as evidenced by K/Ca and K/Ca + Mg ratios in the plant.The C content of the soil was progressively increased, as was the wet aggregate stability and water retention with rate of addition of organic material. Energy of aggregate rupture, energy to initial runoff, erosion, and infiltration were not significantly influenced. It was not visually evident that significant changes occurred in soil tilth because of treatment differences.Marshall soils are well aggregated, have favorable physical and chemical properties, and although erosive, physical problems are not usually observable in the field. Corn grain yields averaged near 7,000 kg/ha (112 bu/acre) in the later years of the experiment, again suggesting that the physical properties of the soil on all treatments were favorable.
Changes in the Concentration of Nitrogenous Fractions in Alfalfa Herbage with Advance in Maturity1
Authors: Lee Chin‐tian , Smith Dale 
Published: July 2010

AbstractLittle information is available in which changes in the concentrations of total, protein, nonprotein, ammonium, nitrate:, free α‐amino, asparagine, and glutamine N in alfalfa (Medicago sativa L.) herbage have been measured at successive growth stages in the same investigation. In the current study, concentrations (% dry weight) of these N fractions were analyzed for the leaflets, stems, and total herbage of ‘Vernal’ alfalfa sampled when the spring growth in 1966 was 25‐, 41‐, and 53‐cm tall, and at first, 25%, and 75% flower.All N fractions decreased in percentage in the leaflets, stems, and total herbage with advance in maturity. Percentages of total N, protein N, and non‐protein N were higher in the leaflets than stems at all stages of growth, while percentages of ammonium N and glutamine N were similar in leaflets and stems. In contrast, percentages of nitrate N, free a‐amino N, and asparagine N were higher in the stems than leaflets. Percentage decreases in the concentration of N f.ractions in the total herbage from the youngest (25‐cm tall) to the oldest (75% flower) stage ranged from a low of 50% for protein N to a high of 75% for nitrate N.
Dispersion and Deposition of Corn Pollen from Experimental Sources1
Authors: Raynor Gilbert S. , Ogden Eugene C. , Hayes Janet V. 
Published: July 2010

AbstractThe atmospheric dispersion and subsequent deposition of corn (Zea mays L.) pollen emitted from plants in two 18‐m diameter plots were studied in 39 tests at Brookhaven National Laboratory to compare the spread of this large pollen to that of smaller pollens studied previously. Concentrations were measured by wind‐impaction samplers mounted at four heights (0.5 to 4.6 m) and at five distances from the source on 20‐degree radii. Deposition was measured by greased microscope slides on the ground.Data were analyzed in terms of current meteorological dispersion theory. Normalized centerline concentrations, crosswind integrated concentrations, plume widths and heights, and mass flux are presented as functions of distance and compared to similar data from ragweed (Ambrosia) and timothy (Phleum pratense) sources of comparable size. Normalized centerline and crosswind integrated deposition and velocity of deposition are also presented as functions of distance and are compared to ragweed and timothy pollen data. The study shows that corn pollen is not transported as far by the wind as smaller pollens, does not disperse as widely in either the horizontal or the vertical direction and settles to earth more quickly, much of it within the source itself.The dispersion of corn pollen is influenced by its large size and rapid settling rate. At 60 m from the source in the downwind direction, concentrations average about 1% of those at 1 m. Width of the pollen plume at 60 m is less than that of smaller pollens under similar conditions. The rate of settling opposes the rate of upward dispersion so that the height of the pollen plume does not increase continuously with downwind distance. At 60 m from the source concentrations integrated in the crosswind direction average from 3 to 6% of those at 1 m. The total amount of pollen remaining airborne at 60 m is 5% of that at 1 m.Total deposition within the source plot is greater than that outside. Deposition per unit area at 60 m downwind is only 0.2% of that near the source. Crosswind integrated deposition at 60 m varies from 0.5 to 0.8% of that at 1 m. The velocity of deposition at 32 m from the source averages about 33 cm/sec.
Improved Reciprocal Grafting Technique for Soybeans (Glycine max L.)1
Authors: Bezdicek D. F. , Magee B. H. , Schillinger J. A. 
Published: July 2010

AbstractA technique for reciprocal root‐scion grafting of soybeans is described using plastic straws and small rubber bands in place of pressure tape commonly employed. The technique described is simpler and faster than the pressure‐tape method of grafting; success of greater than 90% was obtained in our experiments.
Laboratory and in vitro Evaluation of Inbred and F2 Populations of Brown Midrib Mutants of Zea mays L.1
Authors: Lechtenberg V. L. , Muller L. D. , Bauman L. F. , Rhykerd C. L. , Barnes R. F. 
Published: July 2010

AbstractThe purpose of this research was to determine the effect of brown midrib mutants on the lignin percentage and in vitro dry matter disappearance (IVDMD) of corn (Zea mays L.) stover. F2 populations of corn carrying the brown midrib mutants bm1, bm2, and bm3, were grown under field conditions and harvested at 35 and 55 days post‐silking. Plants harvested at 35 days post‐silking were separated into several parts. Samples were analyzed for structural composition and in vitro dry matter disappearance using detergent solution and rumen fermentation techniques, respectively. Stover, harvested 55 days postsilking, contained 8.15, 8.07, 4.96, and 8.81% acid detergent lignin for genotypes bm1, bm2, bm3, and F2 normal, respectively. The IVDMD percentages were 49.3, 47.6, 56.3, and 46.2, respectively. At 35 days post‐silking, the lignin content was lower and the IVDMD higher in bm3 than in the other genotypes for all plant parts except the kernel. The structural composition and IVDMD of normal corn was similar to that of a commercial hybrid included in the study.Mutant inbred lines (Tr background) of bm1, bm3, bm2, bm3, and bm4 were also evaluated. Mutants bm3 and bm1bm3 were lowest in lignin and highest in IVDMD. In both the inbred and F2 populations, structural components other than acid detergent lignin did not differ appreciable among the genotypes.Since lignin limits the digestion and utilization of fibrous feeds by ruminant animals, the possible use of brown midrib mutants for improving the nutritional quality of corn stover and silage appears promising. Mutant bm3 appears to have the most potential for this purpose.
Cotton Growth Response and B Distribution from Foliar Application of B
Authors: Anderson O. E. , Ohki Kenneth 
Published: July 2010

AbstractFoliar application of B has been frequently used to ameliorate B deficiency in cotton (Gossypium hirsutum L.) in the field. This study was initiated to provide information on B distribution pattern and growth responses from foliar application under greenhouse conditions.Boron was applied to cotton foliage in the greenhouse at three application dates by paint or spray application at the 5 to 7‐leaf, early square, and early boll stages. Plants were harvested between 6 and 72 days after application. Growth responses and B content of tissues were related to applied B.Within application periods, foliar applied B had no effect on top growth, root development, reproductive tissue, plant height, and node number. Boron content of treated leaf blades, sampled at the first harvest after application, showed B levels greater than controls. As indicated by B analysis of petiole and young tips, no evidence of B retranslocation in the main stem tissues was apparent.
Yield of Flue‐Cured Tobacco and Levels of Soil Oxygen in Lysimeters with Different Water Table Depths1
Authors: Campbell R. B. , Seaborn G. T. 
Published: July 2010

AbstractFlue‐cured tobacco (Nicotiana tabacum L.) was grown in lysimeters with static water. table levels at, 30, 45, 60, and 90 cm below the soil surface to more clearly define the level at which a favorable balance between soil aeration and water supply is attained. The oxygen and CO2 content of the soil air was determined periodically at various depths. Water‐table treatment effects were evaluated in terms of root and shoot growth, yield, and quality of tobacco.Dry leaf yields for the 90‐, 60‐, and 45‐cm water‐table treatments were all significantly (P≥0.05) greater than that for the 30‐cm treatment. Yields for the 60‐ and 90‐ cm water‐table levels were larger, but not significantly (P≥0.05) larger than the 45‐cm treatment. The yield difference between the 60‐ and 90‐cm treatments was not significant (P≥0.05). Roots of tobacco recovered from soil above the 60‐ and 90‐cm water tables weighed only 10% more than roots recovered from soil above the 30‐ cm water table. Average CO2 and O2 gradients in the soil above the water table were nearly equal but of opposite sign. Soil environmental conditions imposed by the 60‐cm water‐table treatment of this study provided the most favorable balance between aeration and water supply for tobacco.
Effect of Fertilizer Nitrogen, Phosphorus, and Potassium on Yield and Nutrient Content of Lee Soybeans1
Authors: Bhangoo M. S. , Albritton D. J. 
Published: July 2010

AbstractFurther studies on mineral nutrition of soybeans [Glycine max (L.) Merrill] were needed for better understanding of the relationship between the nutrient contents of the grain and leaf tissue in relation to grain yield as influenced by N, P, and K fertilization.Field experiments with ‘Lee’ soybeans were conducted over a 3‐year period on a Calloway silt loam in southeast Arkansas to obtain data on the effects of various rates and combinations of N, P, and K (112 kg N/ha, 40 kg P/ha, and 75 kg K/ha) fertilizers on grain yield and on the elemental content of leaf tissue and the grain.Marked yield increases were obtained from N and K fertilizers and from various NPK combinations. Yield increases from N ranged from 10 to 15%, and from K, from 9 to 19%. Yield increases in 1967, 1968, and 1969 from NPK over the check were 32.8, 28.3, and 14.7%, respectively.Fertilizer application increased the N and K content of both the leaves and grain and depressed their Ca and Mg content. Soybean yield showed a positive correlation with the N and K and negative correlation with the Ca and Mg content of grain and leaf tissue. Elemental content of the leaf tissue declined with plant age.
Nitrogen‐supplying Power of Some Tropical Soils of Puerto Rico and Methods for its Evaluation1
Authors: Lathwell D. J. , Dubey H. D. , Fox R. H. 
Published: July 2010

AbstractAn evaluation of the N‐supplying power of 10 representative Oxisols and Ultisols of Puerto Rico was made by continuous cropping in the greenhouse. Four chemical extraction methods as well as aerobic incubation procedures were used to obtain an index of N availability in these soils. Nitrogen produced during incubation was highly correlated with N released to the crops. Nitrogen extracted by all of the chemical methods used, especially total N extracted by 0.01 M CaCl2 solution and potassium sulfate, was highly correlated with N uptake by plants. These results showed that substantial quantities of N can be removed from these soils upon cropping. It was also shown that laboratory chemical methods as well as incubation procedures provide a reliable means for evaluating the N‐supplying power of these soils.
Temperature Requirements for Seed Germination of Several Forage Legumes1
Authors: Townsend C. E. , McGinnies W. J. 
Published: July 2010

AbstractSpecies that germinate readily over a relatively wide range of temperatures should be easier to establish in the field than those with highly specific temperature requirements. This study compared the temperature requirements for seed germination of several native and introduced legume species with those of commonly used species.Seed germination of 17 legumes species was studied under dark conditions at alternating temperatures of 5 C – 20 C, 15 – 25 C, 20 – 35 C, and constant 20 C. Duration of the alternating temperatures was 12 hr. Seedling counts were taken on the 7th, 14th, 21st, and 28th days of germination.Species differed significantly in germination response to temperature. Medicago sativa L. var ‘Ladak 65,’ Onobrychis viciaefolia Scop. vat. ‘Eski,’ Oxytropis riparia Litv., an unidentified Astragalus sp., A. canadensis L., A. galegiformis L., and A. falcatus Lam. were considered to be temperature‐insensitive for total germination because there was very little difference in percentage germination within each of these species on the 28th day at the four temperature treatments. Half of these species, however, were at least moderately sensitive to temperature for rate of germination.There was considerable interaction among some species and temperatures for both total germination and rate of germination. Astragalus glycyphyllos L., A. globiceps Bge., A. dahuricus (Pall.) DC., and A. chinensis L. required relatively high temperatures (15 – 25 C or 20 – 35 C) for good germination. These temperatures, however, markedly reduced germination of Desmanthus illinoensis (Michx.) MacMill. The 20 – 35 C treatment also seriously reduced germination of Coronilla varia L. var. ‘Chemung’ and slightly reduced germinatiou of Astragalus striatus Nutt., A. flexuosus (Dougl.) G. Don, and Vicia tenuifolia Roth. In comparison to other treatments, rate of germination at constant 20 C was especially high for V. tenuifolia, D. illinoensis, and C. varia. Germination response of Astragalus cicer L. differed from other species. Rate of germination and total germination increased with increase in temperature through 15 – 25 C. At 20 – 35 C, total germination dropped substantially, but rate of germination remained high.Temperature requirements for seed germination of some species suggest why they are relatively easy or difficult to establish in the field. The species that germinated well at most temperatures but are difficult to establish are very small seeded.
Influence of Row Width and Population Density on Yield and Fiber Characteristics of Cotton1
Authors: Hawkins B. S. , Peacock H. A. 
Published: July 2010

AbstractA critical need to evaluate methods to reduce production costs of Upland cotton (Gossypium hirsutum L.) to help maintain its. competitive market position, prompted experiments designed to evaluate the influence of row width and plant population on yield and fiber properties. Upland cotton was grown in 25.4‐, 50.8‐, 76.2‐, and 101.6‐cm‐spaced rows with population levels of 128,000 (low) and 256,000 (high) plants/ha at three locations in Georgia. Significant differences in yield due to test location and to row width were found, but differences in plant populations did not affect yield.Seeding with a modified grain drill produced 88% of the plants desired at the low population level and 82% at the high population level, but left much to be desired in uniformity of seed distribution, placement, and coverage.We found no difference in lint percentage and seed size except that due to location. Boll size was affected by plant population and location but not by row width. The only fiber characteristic affected by row width was fiber fineness. Earliness was influenced only by location. Significant interactions of row width × location were found for yield, number of plants, lint percentage, and fineness. The population × location interaction was significant for boll size and number of plants. The second order interaction of population × row width × location was significant for boll size. Results relative to yield were encouraging and indicated that the narrow‐row, high‐population system might provide partial solutions to some production problems.
Effect of Rates of Nitrogen on Yield, Nitrogen Use, and Winter Survival of Midland Bermudagrass [Cynodon dactylon (L.) Pers.] in Appalachia1
Authors: Mathias E. L. , Bennett O. L. , Lundberg P. E. 
Published: July 2010

AbstractThis study was conducted to determine if Midland bermudagrass [Cynodon dactylon (L.) Pers.] could be utilized in the region of Appalachia as a summer forage during the midsummer months when cool‐season grasses are relatively nonproductive. The effects of N rate on yield and longevity of Midland bermudagrass were studied for 3 years in northern West Virginia. Nitrogen at rates of 112, 224, 448, and 672 kg/ha/yr was split into three equal applications. Dry matter yields were increased with each increment of N during the 1st and the 2nd years and through the 448‐kg/ha rate in the 3rd year. Nitrogen content of the forage increased with increasing rates of N and was greater in the second harvest than in the first. Percent recovery of applied N was highest at the 224‐kg/ha rate in the 1st and the 2nd years and at the 448‐kg/ha rate in the 3rd year. Where adequate N was supplied, bermudagrass competed effectively with native grasses and thus survived three winters, even though the temperatures reached as low as −22 C. By the 3rd year annual yields were as high as 16,000 kg/ha.
Determination of Total Nitrogen in Plant Material1
Authors: Nelson D. W. , Sommers L. E. 
Published: July 2010

AbstractA simple and precise procedure for estimating total N in plant tissue is described; a modification is also described for analysis of samples containing high nitrate concentrations. Plant tissue samples are placed in pyrex Folin‐Wu tubes and digested with a salt‐catalyst‐sulfuric acid mixture by heating the tubes in an aluminum block. Samples are digested at the boiling point of the mixture for 60 min after initial clearing of the digests. Analyses of diverse plant materials, containing from 0.006 to 0.3% NO3‐N3 indicated that the proposed and standard AOAC procedures yielded essentially the same total N values. The coefficient of variation for the proposed methods varied from 0.87 to 1.10%. The tube digestion procedures described allows digestion of 60 plant samples simultaneously and thus greatly improve the efficiency of total N determinations.
Visual Quantification of Wheat Development1
Authors: Haun J. R. 
Published: July 2010

AbstractChanges in the morphology of winter and spring wheat (Triticum aestivum L. em. Thell.) were quantified in a manner to provide a continuous numerical expression of plant development during the formative growth period. The notation system makes use of the regular appearance of leaves at the growing point. Each new leaf represents a unit of development. After the flag leaf has emerged the remaining visible morphological development is divided into four additional units. The growth units are subdivided into decimal fractions beginning with the appearance of each leaf or subsequent unit and ending with the appearance of the next. The daily status or stage of plant development is designated as the total number of units plus the fractional portion of the next unit. The rate of development is determined by subtraction of the previous stage of development from the current stage. Statistical analyses were made to determine the validity of the system with respect to uniformity of designated development units. The system of observation provides a convenient and sensitive method for objectively documenting the status of development throughout the season, or for evaluating the growth response to various treatments or environmental conditions.