bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Fertilizer and Fritted Trace Element (FTE 503) Levels and Placement on Snap Beans Grown on a Tiwiwid Sand1
Authors: Saxena G. K. , Locascio S. J. 
Published: July 2010

AbstractNutritional requirements of vegetables grown on noncoastal regions of Guyana have not been established. The present study was conducted on a major soil type in these areas, a Tiwiwid sand (Typic Quartzipsamments) to evaluate the effects of fertilizer rate and placement and fritted trace element (FTE 503)4 rate on nutrient uptake, root distribution, and yield of snap beans (Phaseolus vulgaris L.). Fertilizer levels were 79‐67‐112 and 158‐67‐224 kg/ha on the area fertilized and were applied on one‐third, two‐thirds, and the full bed. FTE 503 treatments 44.8 kg/ha and no application.Snap bean yields were reduced from 1,008 kg/ha at the lower fertilizer rate to 727 kg/ha at the high rate. With the application of FTE 503 and the low fertilizer level, yields increased with an increase in the width of the fertilizer band. At the high fertilizer rate, yields were reduced with an increase in the width of the fertilizer band. Application of FTE 503 increased the average dry weight of bean plants from 0.55 to 1.07 and from 1.94 to 5.17 g/plant at the flowering and pod set stages, respectively. Yield increases due to FTE 503 applications were from 216 to 1,800 kg/ha and from 26 to 1,428 kg/ha, when fertilizer rates were 79‐67‐112 and 158‐67‐224 kg/ha, respectively. Mean root concentration in the surface 30 cm of soil were increased from 1.39 to 1.82 cm root/cc soil with an application of FTE 503. Results indicated that application of FTE 503 corrected micronutrient deficiencies and improved the availability of soil water and nutrients.
Optimum Size of Sampling Unit to Estimate Coastal Bermudagrass Yield1
Authors: Soplin H. , Gross H. D. , Rawlings J. O. 
Published: July 2010

AbstractBecause the field‐plot techniques used on ‘Coastal’ bermudagrass [Cynodon dactylon (L.) Pers.] have been empirically transferred from temperate species research, our objective was to define an optimum sampling‐unit size for this species. Optimum size of sampling unit was evaluated under six managements: three heights of available forage (avg. 3.75, 7.50, and 11.25 cm), each maintained by grazing or clipping. Three samplings were made on each treatment, corresponding to early, mid, and late‐summer harvest dates. The basic sampling unit was a 20‐cm square.Plots more nearly square and those perpendicular to the slope gave larger estimates of variance than plots that were parallel to the slope and rectangular. Variance of yield/unit area arranged over plot size‐harvesting date combinations increased with height of available forage.Three weighted coefficients of the logarithm of variance of mean yield by heights, regressed on the logarithm of plot size, were computed. Optimum size of sampling unit, regardless of treatment, was found to be not greater than 20 ✕ 20 cm for a cost function based on hand clipping. Assuming costs associated with mechanized harvest, optimum size was found to be 16, 15, or 10 units in size (respective to the three heights) with the longer dimension parallel to the slope.
Boron Source and Lime Effects on the Yield of Three Crops Grown in Peat1
Authors: Prasad M. , Byrne E. 
Published: July 2010

AbstractThe necessity of adding B in peat soils is recognized. A limited amount of information is available regarding toxic levels of B in these soils. A greenhouse experiment was therefore carried out to measure effects of three levels of lime × four levels of B (including control) × two types of B source on tomato (Lycopersicon esculentum Mill cv. Eurocross BB), cucumber (Curcumis sativus L. cv. Sporu), and sweet corn (Zea mays L. cv. Golden Cross Bantam) in a peat soil. The two sources of B were sodium tetraborate and B‐frit. The crops were grown for about 7 weeks.“Lime had a significant effect on yield of tomato, cucumber and corn, while B‐rate had a significant effect on yield of tomato and cucumber only. B‐rate had a significant effect on B‐concentration of all three crops — B‐source had a significant effect on B‐concentration of sweet corn only.”Visible toxicity symptoms were recorded with cucumber and corn at three times the normal rate of B application. The plant levels of B at which toxicity occurred were 115 and 53 ppm for cucumber and corn, respectively. Hot water soluble B up to 10 ppm failed to produce toxicity symptoms.Significant correlations between hot‐water soluble B and B concentration in plant and B‐uptake suggested that hot‐water soluble B was an effective soil test for peat soils in spite of the fact that it can overestimate the availability of B at high lime levels. The critical values of hot‐water soluble B for deficiency and toxicity are much higher than in mineral soils.
Influence of Salinity and N‐P Fertility Levels on Mineral Content and Growth of Sorghum in Sand Culture1
Authors: Patel P. M. , Wallace A. , Wallihan E. F. 
Published: July 2010

AbstractPlant growth is characteristically depressed at certain levels of salt concentrations yet it sometimes responds to fertilizers even though growth depression can be expected to reduce nutrient requirements and even though fertilizer application increases salinity to some degree. This study was designed to examine tension zones involving interactions between nutrient supply (N and P) and salt concentrations.Grain sorghum (Sorghum bicolor (L.) Moench) was chosen for this study because it is commonly grown in regions of irrigated agriculture where soil salinity is often a problem. Plants were grown to maturity in automatically operated sand culture equipment at two levels each of N and P, each subjected to added Ca‐Na chloride salinity levels of zero, medium (EC = 10 mmho/cm) and high (EC = 20 mmho/cm).Vegetative growth was depressed to about 50% of control at both medium and high salinity, while grain production was depressed to about 35% at medium salinity and to almost none at high salinity. Chemical composition of leaves, in addition to familiar dilution effects and ion competition, revealed increased accumulation of Ca, Na, and CI related to high level of P supply, at high salinity only. When sorghum was grown at salinity levels that permitted reasonable grain production, maintenance of optimum soil fertility was important. However, the required level of nutrient supply was lower in saline than in nonsaline soils because of reduced growth. A critical balance between optimum nutrition and increased salinity from applied fertilizers was also involved.
Relationship of Alfalfa Cultivar Yields to Specific Leaf Weight, Plant Density, and Chemical Composition1
Authors: Porter T. K. , Reynolds J. H. 
Published: July 2010

AbstractThe objective of this study was to determine the relationship of dry matter yield to various plant parameters in 11 alfalfa (Medicago sativa L.) cultivars that represented a wide range of winterhardiness. The parameters measured were specific leaf weight (SLW), plant density, and concentrations of protein‐N, P, K, Ca, and Mg in the forage. Suggestions and reports have been made in the literature that plant parameters such as specific leaf weight and K concentration in the forage are positively correlated with yield of alfalfa. Previous research reports have not contained correlations of all our parameters with dry matter yield from broadcast‐seeded field plots. The cultivars were broadcast‐seeded in 2.1 ✕ 7.6 in plots on a Humic Hapludult soil and harvested five times at approximately 1/10 bloom during the next year.Dry matter yield of cultivars was positively correlated with plant density but not correlated with SLW or with concentration in the forage of any of the following elements: protein‐N, P, K, Ca, Mg. When averaged over all cultivars, the SLW generally was higher on the sampling dates preceded by higher mean air temperatures. When averaged over all harvests, the range in concentration of each element was not large. Apparently correlations previously reported between SLW of alfalfa and net photosynthetic rate on a unit leaf area basis did not extend to yield on a unit land area basis in broadcast‐seeded field plots. Individual elemental concentration of protein‐N, P, K, Ca, or Mg, when sampled at 1/10 bloom harvest, was not a good parameter for evaluating the immediate dry matter production of the alfalfa cultivars.
Influence of Seed Size, Planting Depth, and Companion Crop on Emergence and Vigor of Seedlings in Sweetclover1
Authors: Haskins F. A. , Gorz H. J. 
Published: July 2010

AbstractSeed size has been shown to have an important influence on the emergence and early growth of seedlings of several forage legumes, but only fragmentary information on seed size effects in sweetclover (Melilotus spp.) has been published. Therefore, a 2‐year study was conducted in which spring and fall seedings of small, medium, and large seeds of ‘Madrid’ and ‘N13’ sweetclover (Melilotus officinalis (L.) Lam.) were made at depths of 19, 38, and 57 mm. The spring seeding also included a comparison of a companion crop (oats) with no companion crop. Data on emergence score and plant height were collected for the spring seeding only; stand count and dry matter yield of tops and roots were measured for both spring and fall seedings.The companion crop had little effect on emergence score, but it reduced stand count and plant height, and was highly detrimental to dry matter yield. The performance of Madrid was poorer in all respects than that of N13, an experimental cultivar with relatively large seeds. As planting depth was increased, stand counts decreased, but the performance of plants that emerged from the greater depths was relatively good. The most striking results of increased seed size appeared to be improved emergence score and increased dry matter production.
Herbicides for Establishing Kentucky Bluegrass Turf from Plugs1
Authors: Solon E. G. , Turgeon A. J. 
Published: July 2010

AbstractThe use of herbicides for controlling weeds while establishing turf from seed has been limited by the intolerance of seedling turfgrass plants to many herbicides. However, the introduction of vegetative techniques tor establishing Kentucky bluegrass has presented new possibilites for successfully using herbicides in conjunction with turfgrass establishment. The purpose of this study was to determine whether the use of preemergence herbicides is feasible while establishing Kentucky bluegrass from plugs.Greenhouse studies were undertaken to evaluate the effects of preemergence herbicides on the growth of single‐plant cultures of ‘A‐20’ Kentucky bluegrass (Poa pratensis L.), All herbicides inhibited some aspect of growth as determined by measurements of roots, shoots, density, and rhizomes. In the field, however, only benefin (N‐butyl‐N‐ethyl‐ a,a,a‐trifluoro‐2,6‐dinitro‐p‐toluidine) and bensulide [O‐O‐diisopropyl phosphorodithioate S‐ester with N‐(2‐mercaptoethyl)benzene sulfonamide] reduced the lateral growth of ‘A‐20’ plugs while calcium arsenate and DCPA (dimethyl tetrachloroterephthalate) did not inhibit establishment of the turf compared to untreated plots. Where annual bluegrass (Poa annua L.) was seeded in conjunction with plugging the fastest Kentucky bluegrass establishment and best weed control were in plots treated with oxadiazon [2‐tert‐butyl‐4‐(2,4‐dichloro‐5‐isopropoxyphenyl)‐ Δ2‐l,3,4‐oxadiazolin‐5‐one]. Postemergence applications of endothall [7‐oxabicyclo(2,2,l)heptane‐2,4‐dicarboxylic acid] did not control annual weeds and reduced the amount of ‘A‐20’ in some plots due to its injurious effects on the plugs.
Accuracy of Lysimetric, Energy Balance, and Stability‐corrected Aerodynamic Methods of Estimating Above‐canopy Flux of CO21
Authors: Verma S. B. , Rosenberg N. J. 
Published: July 2010

AbstractMeasurement of carbon dioxide exchange is necessary to indicate rates of photosynthesis in the field. Methods which are accurate over short periods of 15 min to 1 hour can indicate the influence of changing weather conditions on crop photosynthetic activity. Three micrometeorological methods—the lysimetric, energy balance, and stability‐corrected aerodynamic—can be used for field determination of the flux of CO2 to a crop surface. The objective of this paper is to present a detailed comparison of the performances of the three methods. Measurements were made in an oat field at Mead, Neb. Results obtained with the three methods were in good agreement, both on a short‐period and on a daily basis. The calculated CO2 flux agreed reasonably well with estimates from other oat‐photosynthesis studies. Midday CO2 flux rates ranged from about 2 to 3 ✕ 10−7 g cm−2 sec−1. The three micrometerological methods were subjected to detailed error analysis to evaluate the relative influence of errors in measurement of the constituent input parameters used to calculate the flux of carbon dioxide, namely water vapor flux and gradients of vapor pressure and CO2 concentration in the lysimetric method; net radiation, soil heat flux and gradients of vapor pressure, air temperature and CO2 concentration in the energy balance method; and gradients of windspeed, air temperature and CO2 concentration in the stability‐corrected aerodynamic method.
Potential Distributions in the Soil‐Root System1
Authors: Molz Fred J. 
Published: July 2010

AbstractA more complete theoretical understanding of water transport in the soil‐root system depends upon considering the combined effects of the root tissue and soil on water flow. Therefore, equations were developed to describe the steady flow of water in a cylindrical soil‐root system. The main objective was to calculate water potential distributions in the root cortex as well as in the surrounding soil. Results indicate that there will be small water potential gradients in the soil relative to those in the root, with the possible exception of very dry soil conditions. An important implication of the present study is that models designed to predict the pattern in which roots extract water from soil will have to consider the rate‐limiting aspect of the root tissue.
Zinc Accumulation and Growth of Corn Seedlings as Affected by Endosperm Removal1
Authors: Edwards J. H. , Kamprath E. J. 
Published: July 2010

AbstractPrevious work indicated that under low light intensity, seed Zn was the main source for young corn (Zea mays L.) seedlings and that uptake of Zn from an external source was minimal. Experiments were conducted under controlled conditions to determine the effects of endosperm removal on uptake and accumulation of Zn by corn seedlings under varying conditions of light intensity, P levels, and external Zn levels.Corn seedlings were grown three days at light intensities of 30,000 and 14,000 lux. The endosperm was removed from one group of seedlings and left intact on another group of seedlings. Three days later the seedlings were placed in Zn solutions of 0, 0.2, and 1.0 μM ZnSO and either 0 or 0.1 mM P. The uptake of Zn was investigated over a 144 hour uptake period. Endosperm removal did not affect Zn accumulation at the high light intensity. At the low light intensity, Zn accumulation was reduced by endosperm removal at 0.2 μM Zn, but accumulation was similar in both endosperm treatments at 1.0 μM Zn. Root growth was reduced more severely than top growth by endosperm removal at both light intensities as indicated by increasing shoot‐to‐root ratio. This effect was still apparent 216 hours after endosperm removal.Phosphorus treatments did not adversely affect Zn uptake or translocation. The maximum enhancement in Zn uptake was observed when P occurred as an external ion at low Zn concentration and minus endosperm treatment. At low light intensity Zn uptake rate was drastically reduced when P was not present as an external ion.
Soybean Root Anatomy as Influenced by Soil Bulk Density1
Authors: Baligar V. C. , Nash V. E. , Hare M. L. , Price J. A. 
Published: July 2010

AbstractThis research was conducted under controlled greenhouse conditions to investigate the effects of soil compaction on soybean (Glycine max L.) root antomy. Previous research has shown that high soil compaction reduces root efficiency in moving air, water, and nutrients into the plant.Increasing bulk density from 1.65 to 1.95 g/cm3 altered the root anatomy. In the high density soil layers a larger percentage of the root volume was occupied by cell wall material, and the transverse sections of the roots had a wavy outline with ruptured epidermal cells. The vascular cylinder became more oval with a gradual increase in both casparian thickening in the endodermis and wall thickening in the xylem vessels.
Sprinkler Application of P and Zn Fertilizers1
Authors: Hergert G. W. , Reuss J. O. 
Published: July 2010

AbstractThe rapid development of sprinkler irrigation in the Great Plains has stimulated interest in applying fertilizers in sprinkler irrigation water. Sprinkler application and conventional preplant application effects of P and Zn fertilizers on the dry matter yield, nutrient content, and grain yield of corn (Zea mays L.) were compared in 1968 and 1969. Both years preplant P treatments produced a significantly higher dry matter yield during the first 5 weeks of the growing season. No significant difference existed between P treatments after this time. In 1969 plants which received preplant P and Zn contained slightly higher concentrations of P and Zn than the plants which received sprinkler P and Zn. Grain yields were significantly increased by Zn application in 1968 but not in 1969. In 1968 on a Nunn clay loam soil (Aridic Argiustoll) the sprinkler‐applied P did not move below a 4–5 cm depth. On a Haxtun loamy sand (Pachic Argiustoll) in 1969 sprinkler‐applied P moved to a depth of approximately 18 cm. Sprinkler‐applied Zn moved to a maximum depth of 5 cm on both soils.
Soil Physical Conditions Affecting Rice Root Growth: Bulk Density and Submerged Soil Temperature Regime Effects1
Authors: Kar S. , Varade S. B. , Subramanyam T. K. , Ghildyal B. P. 
Published: July 2010

AbstractInformation is lacking on the performance of the rice plant due to variations in temperature regimes in association with other soil physical properties. This investigation, carried out under controlled greenhouse conditions, evaluated the influence of temperature and mechanical impedance of soil, as well as of their interaction, on root and shoot growth of rice (Oryza sativa L. ‘Taichung Native 1’).Four submerged soil temperature regimes (27 to 15 C, 32 to 20 C, 37 to 25 C and 42 to 30 C) thermoregulated in water baths, indicated that the maximum root and shoot growth of rice occurred at 37 to 25 C. Irrespective of the bulk density of soil, the total number of roots at the base and the dry weight and volume of the rice root system significantly increased as the submerged soil temperature regime increased from 27 to 15 C to 37 to 25 C, but decreased at 42 to 30 C.Multiple regression analysis indicated that the number of degenerated roots increased with the increase in submerged soil temperature regime, but decreased with the increase in bulk density of the lateritic sandy loam soil. The multiple correlation coefficient between these three variables was significant at 1% level (R=0.79).With increase in bulk density from low to medium, the dry weight of shoot and root, and the number of roots at the base significantly increased at 27 to 15 C and 42 to 30 C, but decreased at 37 to 25 C in all the three soil textures studied. However, when the bulk density was increased from medium to high levels, the shoot and root growth parameter decreased under all temperature regimes.
Irrigation Schedules for Sugarbeets on Medium and Coarse Textured Soils in the Northern Great Plains1
Authors: Cassel D. K. , Bauer Armand 
Published: July 2010

AbstractAn increase in the access to irrigation water in the Northern Great Plains is effecting large increases in the acreages of soils being irrigated. Much of this water is being applied to medium to coarse‐textured soils which hold a maximum of 7 to 12 cm of available water in a 152 cm deep profile. An investigation was conducted in the field to devise a system, using tensiometers, to schedule the application of irrigation water to sugarbeets growing on these soils. Tensiometers were installed at various soil depths, and irrigation water was applied with a small plot irrigator when soil moisture tension reached a predetermined level.One tensiometer located at the 45 cm depth was equally effective in scheduling as two tensiometers, one positioned at a depth of 30 and one at 61 cm. Maximum crude sugar yields of 8.4 to 8.8 metric tons/ha were obtained in 1971 and 1973, respectively. Total water use efficiency was 0.15 to 0.16 metric tons of crude sugar/ha per cm. The maximum irrigation water use efficiencies were 0.32 and 0.36 for 1971 and 1973, respectively. It is concluded that 56 to 62 cm of water, well distributed throughout the growing season, is sufficient for sugarbeet production is southeastern North Dakota in a year of normal growing season temperatures.
Diffusion and Mass Flow of Nitrate‐Nitrogen to Plant Roots1
Authors: Phillips R. E. , NaNagara T. , Zartman R. E. , Leggett J. E. 
Published: July 2010

AbstractThe transport of plant nutrient ions from the soil mass to plant root surfaces is an important phenomenon in mineral nutrition of plants. Nitrate‐nitrogen, the most important source of nitrogen of non‐leguminous plants, is soluble in soil water and is transported to plant roots by both mass flow and diffusion. It is, therefore, important to understand the relative importance of each of these two mechanisms of transport of NO3‐N to plant roots and the environmental conditions under which each is the dominant mechanism of transport.In order to predict from theory the simultaneous transport of NO3‐N to plant root, several soil and plant parameters must be known. These parameters include the volumetric soil water content, concentration of NO3‐N in soil solution, porous diffusion coefficient of NO3‐N in soil, average macroscopic velocity of soil water at plant root surface, radius of root, transpiration rate and plant root length. These soil and plant parameters must be measured in either the field or greenhouse.The validity and/or consequences of several assumptions of a previously reported steady‐state model describing simultaneous mass flow and diffusion of NO3‐N to plant root surfaces are discussed with reference to experimental measurement of plant and soil parameters. The relative importance of diffusion to mass flow of NO3‐N is large when the ratio of transpiration rate to the constant of proportionality relating flux into the plant to concentration of NO3‐N in the soil solution is less than 0.2 but is negligible when the ratio is greater than unity. The average concentration of NO3‐N of the entire soil mass rather than the concentration of NO3‐N at the outer radius of the soil cylinder associated with each root can be used in the model with little error for most situations expected to occur in the field.