bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimates of Optimum Plot Size and Shape from Uniformity Data in Burley Tobacco (Nicotiana tabacum L.)1
Authors: Gupton C. L. 
Published: July 2010

AbstractTo obtain estimates of optimum plot size and shape for burley tobacco (Nicotiana tabacum L.), we conducted uniformity trials during 1969 and 1970 at Greeneville, Tennessee, and during 1970 at Spring Hill, Tennessee. Each trial consisted of 3,000 plants which were subdivided into 600 basic units of 5 plants each. Data from each basic unit were recorded for yield of cured leaf, number of days to flower, number of harvestable leaves, plant height, and the length and width of the fifth leaf from the top of the plant.Hatheway's “convenient plot size” and Smith's soil heterogeneity index methods were used to estimate optimum plot size. The results from Hatheway's method suggest that the greatest precision would be gained by minimizing the number of plants per plot and maximizing the number of replications in the experiment. Because 25 to 30 plants are required for visual evaluation of burley tobacco, it appears that a convenient plot size for yield and quality trials is 30 plants with the number of replications adjusted to the desired difference to be detected or the maximum number permitted by space and cost of production. We found that most other agronomic characters may be measured with acceptable precision on 10 to 20 plants per plot. For percent total alkaloids, precision is expected to increase rapidly with either an increased number of plants per plot or replications in the experiment. The optimum size of plot for yield computed by Smith's minimum cost procedure ranged from 9 to 179 plants. These results do not appear as useful as those from Hatheway's method.Our data suggest that one‐row plots may be slightly better than two‐row plots. Taking into consideration the optimum number of plants per plot and shape, we concluded that single‐row plots containing 30 plants each are most desirable for yield and quality trials. Smaller one‐row plots with increased replication may be more efficient for obtaining genetic information relative to specific characters.
Establishment of Nine Forage Legumes in the Central Great Plains1
Authors: Townsend C. E. , McGinnies W. J. 
Published: July 2010

AbstractSpecies used in range seedings must be relatively easy to establish in diverse environments. This study evaluated the ability of nine legumes to emerge and to become established from three depths of planting at five locations in the Central Great Plains. The nine species (Medicago sativa L., Onobrychis viciaefolia Scop., Vicia tenuifolia Roth., Coronilla varia L., A. stragalus cicer L., A, falcatus Lam., A. galegiformis L., A. striatus Nutt., and an unidentified Astragalus sp.) were seeded in the spring at 1.3‐, 2.5‐, and 3.8.cm depths. Seedling emergence counts were taken in early summer and stand ratings were made in late summer. Seedling emergence was best from the 1.3‐cm depth at all locations except one where the soil was very sandy and the best emergence was from the 2.5‐cm depth.In general, V. tenuifolia, M. sativa, A. falcatus, and O. viciaefolia gave better seedling emergence than the other five species over all depths of planting at all locations. Although V. tenuifolia gave the best average emergence, it is probably not adapted to the sandy soils of the region, because by late summer most plants had died at the two locations with sandy soil. Emergence of A. cicer was relatively poor, but because of its rhizomatous characteristic, the stand of A. cicer was fair to good at the 1.3‐ and 2.5‐cm depths at most locations by late summer. The small‐seeded entries, A. striatus and Astragalus sp., were very sensitive to depth of planting. Seedling emergence of A. striatus was poor at most depths and locations. Emergence of Astragalus sp., however, was fair to excellent at most locations at the 1.3‐cm depth. Emergence of the large‐seeded species, A. galegiformis and C. varia, was poor at all locations.
A Versatile Small Plot Forage Harvester1
Authors: Smith R. R. 
Published: July 2010

AbstractA versatile, small plot forage harvester developed at the University of Wisconsin is composed of basic, commercially available items such that the power unit (a standard garden tractor) can be used for other maintenance chores. The unit can be assembled and disassembled rapidly (10 min) and has hastened forage harvesting operation.
Influence of Seed Orientation on Bean Seedling Emergence1
Authors: Bowers S. A. , Hayden C. W. 
Published: July 2010

AbstractObservation from an unrelated field bean experiment indicated that certain seed orientations might reduce emergence. Consequently, studies were initiated to determine if orientation variations occur in planting and if these variations influence emergence.Orientation of bean seeds, dropped into both “V” and flat‐bottom furrows, were classified and tabulated. In “V” furrows almost all orientations were possible; 36% assumed the “lay‐flat” orientation. In the flat‐bottom furrow 85% of the beans were in the “lay‐flat” position. The influence of 11 different seed orientations on emergence was evaluated in greenhouse studies. With crusted soils seeds planted “hypocotyl end down” produced significantly less emerged seedlings (1% level) and a lower emergence rate. Orientation effects were observed to a lesser degree in noncrusted soils.The adverse influence of “hypocotyl end down” orientations was attributed to seed rotation within the soil. For controlled plantings the “lay‐flat” orientation is recommended due to both its high frequency of occurrence and high emergence.
A Reliable and Inexpensive Soil Frost Gage1
Authors: Wilen B. O. , MacConnell W. P. , Michelson L. F. 
Published: July 2010

AbstractResearchers have been interested in indirect methods of measuring soil frost penetration because direct methods require laborious digging that destroys the study area. Several indirect soil frost measuring techniques have been developed in the past. The use of commercially produced gypsum electrical resistance blocks has been established as one reliable technique. The research presented in this note will demonstrate that fabricated gypsum blocks are very accurate and durable enough to last several years in soil frost surveys in very acid soils.
Soxlet Glassware Technique for Nutrient Culture Studies1
Authors: Heilman M. D. , Anderson W. B. 
Published: July 2010

AbstractStandard Soxlet extraction glassware was used as plant containers for nutrient culture experiments. The thimble reservoir served as the root chamber. Fresh nutrient solution was continuously exchanged in the root growth chamber by a self‐pumping technique utilizing air injected into the bulk solution for lifting the newly aerated solution to the root growth chamber.
A Computerized Personal Bibliographic Reference System1
Authors: Strand R. H. , Fribourg H. A. 
Published: July 2010

AbstractA computer program for the creation and maintenance of an indexed personal bibliographic reference file is described. It is capable of providing an alphanumeric listing of all entries in a reference file, an alphabetic listing of all sources referenced, an alphabetic listing of all authors present, and an alphabetic index of all meaningful words (key words). In addition to the printed index for key word search, the system, which does not require sophisticated computer expertise, provides simple means for organizing, adding, or retrieving references. After the initial computer file creation, minimal computer access is required for updating the file.
Rate and Time of Nitrogen Application on Blueboy Wheat (Triticum aestivum L.)1
Authors: Clapp J. G. 
Published: July 2010

AbstractThe semi‐dwarf, stiff‐strawed soft winter wheat variety ‘Bineboy’ (Triticum aestivum L.) was released in 1965 by the North Carolina State University Agricultural Experiment Station. Presumably, its greater straw strength would allow producers to use higher rates of nitrogen without as much risk of lodging. Information was needed, however, on the nitrogen requirements of this new type of wheat and the most beneficial time for these applications.Field experiments were conducted on two soil types (Davidson clay loam and Lynchburg fine sandy loam) for 2 years to determine the response of Bluehoy wheat to nitrogen rates of 56, 112, 168, and 224 kg/ha applied at seeding in October or partly in October at seeding (56 kg/ha) and partly in February as topdressing rates of 56, 112, and 168 kg/ha.Applying all the nitrogen at seeding on the Davidson clay loam was just as effective for high grain yields and high test weight as the split applications. The 112 kg/ha applied in October (seeding) on this soil type was sufficient for maximum yields.Grain yields were lower on the Lynchburg fine sandy loam soil for October applications than for February applications at nitrogen rates of 112 and 168 kg/ha. No difference in yield was obtained for the two dates at the highest rate of nitrogen (224 kg/ha).Test weights were significantly lower both years when the nitrogen was applied in February on the Lynchburg fine sandy loam as compared to the same total rate applied at seeding. A similar trend was also found for the February nitrogen applications on the Davidson clay loam.This study shows that Blueboy wheat producers can apply all of the nitrogen fertilizer to clay loams and fine sandy loam soils at the time of seeding rather than splitting the application into a small amount at seeding followed by a topdressing in February. A higher level of nitrogen fertilization will be required, however, to offset possible losses from leaching on soils with a sandy surface texture. On these soils producers must weigh the cost of using a higher nitrogen rate at seeding against the possibility of producing a lower‐quality wheat and the cost of an extra trip over the field in February when fields may be wet.
Utilization of Pelleted Phosphorus by Flax, Wheat, Rape, and Buckwheat from a Calcareous Soil1
Authors: Strong W. M. , Soper R. J. 
Published: July 2010

AbstractReaction zone root development and P absorption efficiency of roots of flax (Linum usitatissimum L. ‘Redwood’), wheat (Trlticum vulgate L. ‘Manitou’), rape (Brassica napus L. ‘Tanka’), and buckwheat (Fagopyrum esculentum Moench) have been contrasted in order to explain the large variability among them in utilizing P from pellets of KH2PO2 and K2HPO4 in a pot experiment. A large proportion of plant P was extracted from the pelleted applications by rape (40.8 to 57.6%) and buckwheat (33.1 to 55.5%). It is suggested that applied P utilization by rape was enhanced by e~tensive proliferation of its root system detected around points of application of fertilizer pellets. It is suggested for buckwheat, on the other hand, that its utilization of applied P was aided by the high efficiency of its root in absorbing P from high concentrations as indicated in absorption studies using excised roots. Relative to rape or buckwheat a much smaller proportion of plant P was extracted by flax (3.8 to 8.1%) and wheat (12.5 to 19.7%) from P applications. The poorer utilization of applied P by these two crops is considered due to the inability of their root systems to either proliferate extensively or to absorb P efficiently from high P concentrations.It is reasoned that the greater P availability from a 40‐mg P application as KH2PO4 than from a 20‐mg P application as K2HPO4 was due to the higher water‐soluble P level in the reaction zone of the former application, with the two applications spread through the same soil volume. A given P application as K2HPO4 spread through a larger volume of calcareous soil than the same rate of P as KH2PO4. The water‐soluble P level, however, was lower in reaction zones of the former carrier. Thus, the effect of reaction zone size and of its watersoluble P level on the availability of P from KH2PO4, and K2HPO4 pellets offset one another, resulting in a similar availability of the two carriers to the four crops tested.
Effects of Subsurface Asphalt Layers on Corn and Tomato Root Systems1
Authors: Saxena G. K. , Hammond L. C. , Robertson W. K. 
Published: July 2010

AbstractIn recent years several reports have indicated an improved crop production on droughty sands treated with a subsurface asphalt layer at depths of about 60 cm. Root growth in these modified soil profiles has not been investigated. This study was initiated to determine the nature and reason of any influence of a subsurface asphalt layer on root growth and distribution in the soil profile.Observations of root distributions of sweet corn (Zea mays L. var. ‘Rugosa’) and tomato (Lycopersicon esculentum Mill. var. ‘Commune’) were made in freshly dug pits. Root sections in and out of the asphalt layer were photographed and examined microscopically for morphological effects. The “line‐intercept” method was used to obtain quantitative measurements of root concentration (cm root/cc soil) of field corn (Zea mays L).Tomato roots in the asphalt layer were larger in diameter and showed damage to cells in the cortex. Rooting of all crops was less extensive in soil below the asphalt layer than in soil at the same depth without the asphalt. Concentration of corn roots in the top 60 cm of soil averaged 1.6, 1.7, 2.0, and 2.2 cm/cc for the following respective treatments: control, control with irrigation, asphalt layer, and asphalt layer with irrigation. This compensation effect would limit any reduction in value of the root‐resistant asphalt layer to situations of low rainfall without irrigation.
Factors Affecting the Development of Flue‐Cured Tobacco Grown in Artificial Environments: IV. Effects of Carbon Dioxide Depletion and Light Intensity1
Authors: Raper C. David , Downs R. J. 
Published: July 2010

AbstractPlants grown in controlled‐environment rooms are usually under a CO2 stress that the so‐called “make‐up air systems” do little or nothing to alleviate. Tobacco (Nicotiana tabacum L.) rapidly depletes the CO2 from 400 ppm (v/v) ambient level to 200 ppm. This report evaluates the effects of this CO2 stress by comparison with plants grown in an atmosphere where CO2 was maintained at the ambient 400 ppm level by supplemental CO2. Light intensities of 215, 322, and 450 hlx were superimposed on both CO2 regimes. Plant development was evaluated by physical and chemical properties of mature leaves and has been compared not only among the imposed treatment conditions, but also with the development that occurs in a natural field environment.Several abnormalities of tobacco were noted under CO2 stress. These include: a low concentration of reducing sugars in the cured leaves, presumably reflective of low soluble carbohydrate accumulation in mature leaves; reduced internode elongation; and epinasty of leaves during maturation. A reduced dry matter accumulation in aerial organs, concomitant with the reduced internode growth, was recorded under the CO2 stress. Only small differences between CO2 levels occurred for dry matter accumulation in leaf tissue.Decreased light intensity increased accumulation of nitrogen and potassium by the plants independent of CO2 level. Most of this increase was attributed to actively expanding tissue, in this case to growth of secondary meristems.
Grain Sorghum Yields in One‐Row and Two‐Row Plots1
Authors: Ross W. M. 
Published: July 2010

AbstractFour combine grain sorghum hybrids, Sorghum bicolor (L.) Moench, were yield tested for 5 years in west‐central Kansas in one‐row and in two‐row plots with each hybrid as a border to determine relative reliability of data from the two plot types. Though ranks of hybrids remained the same, regardless of plot type or border, yields of individual hybrids varied from −5 to +10% in single‐row plots and from −2 to +5% in two‐row plots depending on the border rows. In addition, a strongly competitive hybrid, like RS 610 yielded more when bordered by some other hybrid, and a weakly competitive hybrid, like RS 650, yielded less. Average differences were: RS 610 (1‐row plots, 290 kg/ha), RS 610 (2‐row, 100), RS 650 (l‐row, −130), and RS 650 (2‐row, −20).Two‐row plots, and sometimes multiple rows, are deemed desirable for refined experiments and for tests in areas where growing conditions may be suboptimum. One‐row plots appear to be practical for routine programs involving high entry numbers, for increasing replications, or for testing at additional locations without enlarging total seed and land requirements.
Agronomic Investigations Using Continuous Function Experimental Designs—Nitrogen Fertilization of Sweet Corn1
Authors: Fox R. L. 
Published: July 2010

AbstractSimple experimental designs are needed for exploratory field studies and for generating data for well defined yield response curves and surfaces. A design was developed by which a variable was increased in many small increments along corn (Zea mays L.) rows. Individual plants were handled as plots. Sweet corn was grown in rows 12 m long, along which rates of N fertilization increased in 40 increments from 0 to 220 kg/ha. Replication was obtained by repeating the layout but rotating it through 180 degrees. “Border effects” along the row could be ignored because the incremental change of applied N was very small and because the N rate increased in one direction and decreased in the other. Because there are many experimental points it was possible to show that low rates of N produced a “diluting effect” on leaf N, that N deficiency symptoms disappeared and second ear develop ment began at about 140 kg N/ha, that lower corn leaves are the most sensitive indicators of the N status of corn, and that yield response to applied N was linear to 200 kg/ha of N applied. If a second factor is varied at right angles to the first, a well defined response surface can be obtained.
Growth and Chemical Composition of Crownvetch as Affected by Lime, Boron, Soil Source, and Temperature Regime1
Authors: Bennett O. L. , Mathias E. L. 
Published: July 2010

AbstractCrownvetch (Coronilla varia L.) was grown in environmental chambers at three temperature regimes using lime and boron applications separately and in combination on Gilpin shaly silt loam soil from north and south exposures. Temperature regimes were (T1) 18.3 C day — 12.8 C night; (T2) 23.9 C day — 18.3 C night; and (T3) 29.4 C day — 23.9 C night. Liming increased both root and top growth in all instances There was a significant plant growth response to temperature regime, soil from different exposures, lime, and temperature × lime interaction. Application of boron increased yields of plants grown on soil from the northern exposure but not on soil from the southern exposure. Application of boron, with or without lime, increased boron content of crownvetch, but lime applications reduced the amount of uptake. The T2 temperature regime was optimum for top growth but T1 was optimum for root growth. Soil pH ranged from 4 to 5.6 by the end of the study; growth of crownvetch did not appear to be impaired at these low pH values when lime had been applied.Liming increased Ca but reduced P, K, Mg, Mn, Zn, B, Na, and Cu concentrations of plants. Application of boron to soil increased B and Fe concentrations of plants, especially at T2 and T3. Phosphorus concentration of plants was higher at T2 and T3 than at T1; however, Fe, Al, and Mg concentrations generally decreased with increasing temperature.
Spraying Alfalfa Hay with Water Before Baling to Minimize Harvesting Losses1
Authors: Anderson M. J. , Mickelsen C. H. 
Published: July 2010

AbstractDry alfalfa (Medicago sativa L.) hay was sprayed with a fine mist of water before baling to determine if harvest losses could be reduced to the same level as dew‐moistened hay. Three studies were conducted. Study I compared hay that was dry, dew‐moistened, and sprayed with 1 liter of water per 4 m (1–4) of windrow. Study II compared the 1–4 rate to 1 liter of water per 2 m (1–2) of windrow. Spraying preceded baling by 5 to 10 minutes in studies I and II. Study III compared dry, dew‐moistened, and sprayed at the 1–4 rate 0, 5 and 10 minutes before baling. Strips over 150 m long were harvested with a 3.65‐m swather‐conditioner. Each swath was a replicate. There were 10, 6, and 11 replicates per study, respectively. Yields, chemical composition, and digestibility were determined. Digestibility and yields of dry matter (DM) and digestible DM were approximately 4, 1, and 6% higher for the sprayed hay than for the dry hay in study I. Yield of sprayed hay and dew‐moistened hay were comparable. Yields were slightly higher for the 1–2 spraying rate than for the 1‐4 rate but the differences were not significant. In study III yields were not as high for sprayed hay as for dew‐moistened hay. The 0 and 5 minute spray treatments had higher yields than the dry hay. We believe a higher spraying level should have been applied in study III. Spraying hay with water will reduce DM losses and increase nutritive value when dry, brittle hay is harvested.
Influence of Applied Nitrogen on the Performance of 23 Orchardgrass (Dactylis glomerata L.) Varieties1
Authors: Frank K. D. , Pesek John 
Published: July 2010

AbstractOrchardgrass (Dactylis glomerata L.) pastures and the N fertilization of these pastures are important to beef cattle production in the humid and subhumid parts of the United States. Nitrogen in excess of 200 kg/ha per year is required for economic yields. We studied the influence of two levels of N (270 and 540 kg/ha per year) on forage yield, concentration of NO3‐N, N, P, and K or 23 orchardgrass varieties from diverse areas of the world.NO3‐N, total N, percentage of P, and forage yield were affected significantly by applied N, varieties, and time after application of N. Percentage of K was influenced by varieties and time after application of N. Percentage of P in the forage tended to decline with increased N, but remained above the level considered adequate for optimum production.The late‐maturing varieties, as a group, contained higher concentrations of NO3‐N and total N, and produced less total dry matter than did medium‐ and early‐maturing varieties. Variability also existed among varieties within a maturity group, and more variability was observed at the higher rate of applied N. Concentration of NO3‐N at the high rate of N varied from 0.3 to 0.8%.Positive linear relationships were observed between NO3‐N content and total N content for the individual forage harvests.
A Cost‐Benefit Evaluation of Controlled‐Environment Research Versus Field Research1
Authors: Raper C. David 
Published: July 2010

AbstractTo evaluate the comparative costs of controlled‐environment and field research, a ledger has been formulated to consider the base expenditures—those expenses incurred in the routine operation of the field and controlled‐environment facilities—and the variable expenditures—those incurred in the acquisition of samples and the various chemical, physical, and morphological analyses dictated by the needs of a particular investigation. For a comparable experiment, the base cost of growth‐chamber space in the North Carolina State University Phytotron is more than fivefold the base cost for field‐acreage. This relatively high base cost for controlled‐environment research is offset by a greater variable cost encountered with field research.Examination of the comparative cost‐analysis reveals a strategy for substantially reducing the cost‐benefit ratio for agricultural research by judicious use of controlled‐environment research in complement to field research. This strategy is discussed.