bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaporation from Drying Surfaces by the Combination Method
Authors: Fuchs M. , Tanner C. B. , Thurtell G. W. , Black T. A. 
Published: July 2010

AbstractThe combination formula which explicitly includes the surface temperature is used to predict the hourly evaporation from a drying bare soil. The formula is valid regardless of the water vapor saturation deficit at the surface, but the measurement of the surface temperature limits its application to surfaces having a welldefined boundary with the atmosphere. Agreement with hourly evaporation measured by lysimetry at the same site was only fair because of a thermal lag in the energy balance of the lysimeter, but very good (within 1%) for the average daily values where the effect of thermal tag is negligible. All combination formulas use an aerodynamic transfer coefficient, which must include diabatic profile corrections unless sensible heat flux density is small relative to evaporation. Eddy correlation measurementS of the sensible heat flux density into the air confirmed the transfer coefficient used. It is finally shown that the additional measurement of the water vapor pressure of the air can be used to relate the actual evaporation to a usefully defined potential evaporation.
Effects of N, P, and K and Their Interactions on the Yield and Kernel Weight of Barley in Hydroponic Culture1
Authors: MacLeod L. B. 
Published: July 2010

AbstractThe role of P and K on the utilization of N by Herta barley (Hordeum distichon L.) was studied in a greenhouse hydroponics experiment. Nitrogen was supplied at concentrations of 10, 50, 100, and 200 ppm, potassium at 10, 50, and 200 ppm and phosphorus at 25, and 100 ppm in factorial combination. Adequate concentrations of P and K were required to obtain response to increasing concentrations of N. Interaction effects of NK and NP on tillering and on yield and kernel weight of grain were highly significant. Although both P and K were essential for normal growth and development, K had the greater influence on the utilization of N in vegetative growth and on yield of grain. Plants harvested at the early vegetative, mid‐vegetative (heading), and mature stages of development showed a yield response to N, P, and K.Percentages of N, P, and K in tissue below which final yield of grain decreased were 4.0, 0.70, and 4.0, respectively, for plants sampled at heading. These critical nutrient levels obtained from nutrient culture were higher than for barley grown in soil culture.
Relationship between Tissue Zinc Levels and Maturity Period of Field Beans1
Authors: Boawn Louis C. , Rasmussen P. E. , Brown J. W. 
Published: July 2010

AbstractThe number of days from bean planting to harvest maturity is related to the zinc concentration of either leaf tissue or total top at or prior to bloom stage. In two geographical areas and with two bean varieties, optimum maturity period was associated with approximately 20 ppm or more zinc in these tissues. Below 20 ppm, the number of days required to reach maturity increases rapidly. With zinc levels below 15 ppm there was an increase of up to 30 days in the time required to reach maturity.
Formation, Elongation, and Longevity of Barley Root Hairs1
Authors: McElgunn J. D. , Harrison C. M. 
Published: July 2010

AbstractThe root hairs of 1‐month‐old intact barley (Hordeum vulgare L.) seedlings, grown in a growth chamber, were observed at three different constant root temperatures.Formation and elongation of root hairs were recorded hourly over 24‐hour periods. Death of root hairs was indicated by the use of neutral red; from these data longevity was determined.The number of root hairs formed was greater at 18 and 26C than at 15C. Formation was periodic, with three maxima and two minima rates. The changes in formation rates did not coincide precisely at each temperature.Elongation was greater at 26C than at 15C. The elongation rate was constant for each of the three temperatures over a 24‐hour period.Longevity of root hairs was 40, 45, and 55 hours at 26, 18, and 15C, respectively. A maximum number of deaths occurred 13 to 15 hours after the initiation of the light period.Phasic formation and death of root hairs may affect diurnal water absorption due to changes in the living and dead root hair areas. Elongation rate may also affect diurnal water uptake, in that elongation rate is affected by soil conditions.
Visual Estimates and Clipping Plot Size for Evaluating the Forage Potential of Small Grain Varieties1
Authors: Atkins I. M. , Merkle O. G. , Pawlisch Paul E. 
Published: July 2010

AbstractVisual estimates of the forage value of oat and barley strains were compared with forage yields in 1960 and 1961. Correlations between January estimates and forage yields were highly significant statistically but in the range of 0.40 to 0.50**. Combining January estimates with March estimates, and correlating these with total seasonal yields of forage, gave correlations of 0.55 to 0.66**. Values of this magnitude give considerable confidence in visual estimates for selecting desirable forage producing lines in a breeding program. Correlations between independent estimates of two individuals, were from 0.56 to 0.88**. Correlations of forage yields with 5‐rain yields of the same plots were near zero, suggesting that the evaluation of new strains, based largely on grain yields, fails to recover the best forage types.Forage samples from 0.1858, 0.3716, and 0.7432 m2 were compared in four seasons, 1959‐62. With a few exceptions, correlations of yields of different plot sizes were good. The coefficients of variability for the 0.1858 m2 plots were usually higher than those of the larger plots. With full stands and proper border protection, it appears that small areas can be utilized satisfactorily for determining forage yields of small grain varieties.
Boron Nutrition of Sugar Beet, Cotton, and Soybean1
Authors: Oertli J. J. , Roth J. A. 
Published: July 2010

AbstractThe levels of boron in nutrient solutions suitable for plant growth are highest for sugar beet, (Beta vulgaris) lowest for soybean (Glycine max), and intermediate for cotton (Gossipium hirsutum). In spite of pronounced differences in B tolerance (and also of B requirement), tissue levels at which toxicity symptoms appear are similar in the three species. The species differences are therefore due more to B uptake and growth characteristics than to tissue sensitivity. Chlorotic tissues contain around 1,000 ppm B, necrotic tissues above 1,000 ppm.Beet yields and beet sugar contents in greenhouse experiments were not affected by B concentrations up to 40 ppm. Thus the sugar beet might be a suitable plant for high B soils, provided the result is not modified in the field by different climatic conditions.Boron distribution, patterns of B toxicity, leaf venation, correlation between B injury and leaf age all support the hypothesis that within the leaf, B moves largely in the transpiration stream and is accumulated to toxic levels as water is lost to the atmosphere.
Differential Aluminum Tolerance of Winter Barley Varieties and Selections in Associated Greenhouse and Field Experiments1
Authors: Reid David A. , Jones G. D. , Armiger W. H. , Foy C. D. , Koch E. J. , Starling T. M. 
Published: July 2010

AbstractThirty cultivars and experimental strains of winter barley (Hordeum vulgare) were grown on acid, aluminum‐toxic soils treated with two rates of lime in greenhouse tests and three rates in field tests. The objectives were to determine if greenhouse tests could be used for certain phases of breeding for Al‐tolerant barley varieties and to find possible new sources of Al‐tolerant germ plasm.Dry‐weight yields of top and root growth were determined after 7 weeks in the greenhouse. Grain yields were determined from field plots. Correlation coefficients between root and top yields in the greenhouse were 0.93 for the low lime rate and 0.71 for the high rate. Root and top yields at the low lime rate in the greenhouse were highly correlated with grain yield in the field with no lime added (r = 0.77 and 0.66, respectively) but there was no significant correlation between the same measurements at the high lime levels.Results of these studies indicate that plant populations of barley can be initially screened for Al tolerance in pots of Al‐toxic soil in a greenhouse. Al tolerance is apparently genetically controlled.Experimental lines derived from backcrossing to A1‐tolerant parents were also tolerant. Selection for A1 tolerance in a mixed population on acid, A1‐toxic soil in the field was demonstrated.
Some Effects of High Salinity on Germination and Emergence of Barley (Hordeum vulgare L. emend Lam.)1
Authors: Donovan T. J. , Day A. D. 
Published: July 2010

AbstractA number of barley strains with geographical origins similar to ‘California Mariout’ and other commercial varieties were germinated in salinized water and soil cultures in Tucson, Arizona. Of 39 barleys studied, approximately one‐third equalled or exceeded the germination of California Mariout in highly saline cultures. Their emergence in salinized soil followed the same trends as their germination in petri dishes. Most commercial varieties had lower germination salt‐tolerance than California Mariout and the more tolerant USDA introductions.Differences were observed between strains in germination under saline conditions. For example, 41% of the seedlings of C.I. 3780 had emerged at the end of 7 days when 20,500 ppm of salts were present in the soil solution. Cereal Investigation 3555, a strain with equally good emergence in non‐saline cultures, had only 24% for the same period. However, after 15 days both entries had similar emergence. At moderate salinity levels most barleys had uniform emergence in soil cultures while at higher levels of salinity only the salt‐tolerant barleys produced satisfactory seedling growth. There was a substantial delay in emergence of all barleys in highly saline cultures.
Dieldrin Uptake by Corn as Affected by Soil Properties1
Authors: Beestman G. B. , Keeney D. R. , Chesters G. 
Published: July 2010

AbstractIn greenhouse experiments, dieldrin uptake by corn was determined on A‐ and B‐horizon samples of three soils taken from a Dodge catena and treated with C14‐ dieldrin at rates of 1 and 5 ppm. Corn was harvested 39, 69 and 90 days after emergence. The soil organic C content was inversely related to the concentration of dieldrin in the roots and shoots of the corn, and was related directly to total dieldrin recovery. No relationship existed between dieldrin uptake, CEC, free iron oxide content or types and amounts of clay size minerals. Less than 3% of the dieldrin applied to the soils was translocated into the aerial portions of corn. The concentration of dieldrin in the root tissue was 20 to 80 times greater than in the above ground portions of the same plant.
Ambient Temperature Effects in Infrared Thermometry1
Authors: Jackson Ray D. , Idso Sherwood B. 
Published: July 2010

AbstractThe output signals of two different infrared thermometers deviated drastically when internal console temperatures rose above 48 and 58 C. Internal temperatures greater than 48 C were observed in both instruments on all clear days investigated, rendering one instrument useless during the warmer parts of these days. In addition, one of the instruments also had a temperature‐dependent calibration curve, which introduced severe uncertainties into its accuracy.
A Self‐Propelled Experimental Plot Foragge Harvester1
Authors: Collins K. L. , Rhykerd C. L. , Noller C. H. 
Published: July 2010

AbstractA self‐propelled forage harvester has been developed at Purdue University for harvesting experimental plots. The major advantages of this harvester are: lower initial and operational cost than presently available equipment on this type; greater maneuverability; easy transportability in a carry‐all or pick‐up truck; an easily controllable ground speed; and a light weight, keeping soil compaction problems to a minimum.
Boron Tolerance of Tall Wheatgrass1
Authors: Schuman Gerald E. 
Published: July 2010

AbstractThe relative boron tolerance of three varieties of tall wheatgrass [Agropyron elongatum (Host) Beauv.], ‘Alkar,’ ‘Largo,’ and ‘Nebraska P. I. 98526,’ grown in nutrient cultures was determined. Alkar was also tested in soil cultures. Boron concentrations responsible for a 50% decrement in growth in nutrient cultures ranged from 33 to 38 ppm water‐soluble B for the three varieties. The B level causing a 50% decrement in growth of the Alkar variety in the soil culture was 46 ppm water‐soluble B in the soil solution.
Foliar Absorption of Urea by Sandblasted Wheat Seedlings1
Authors: Adriano D. C. , Armbrust D. V. , Murphy L. S. 
Published: July 2010

AbstractOne‐month‐old wheat (Triticum aestivum L. sp.) seedlings were exposed to 13.6 m/sec wind velocity and sand at 1 kg/min for different lengths of time in a wind tunnel. Urea solution was foliar applied at different time intervals of up to 4 days after exposure. Total nitrogen content of the tissues decreased as follows: wind plus sand greater than wind alone equal unexposed. There was a strong indication that foliar uptake of urea was greater when the urea solution was applied soon after exposure to wind and sand
Use of a Dead‐Load Technique to Determine Axial Root Growth Pressure1
Authors: Eavis B. W. , Ratliff L. F. , Taylor H. M. 
Published: July 2010

AbstractThe axial root growth pressures generated by cotton (Gossypium hirsutum L.) and pea (Pisum sativum L.) seedlings under different ambient oxygen concentrations were determined by a dead‐load method in which individual roots encased in plaster of paris blocks were loaded differently. Each seedling root could either elongate or not elongate depending on the applied force. The average values agreed well with those reported by Taylor and Ratliff (1969) using a different method.The average root pressures exerted by cotton and peas in an atmosphere of 21% oxygen and at —l/3‐bar matric potential were 11 and 12 bars, respectively, and individual values ranged from 8 to 15 bars. Root growth pressures were similar at 8 and 3% oxygen with peas. However, a 3% oxygen level reduced the root growth pressure of cotton to 5 bars. No significant differences were apparent between results obtained at —1/3‐ and —l/10‐bar matric potential around the root tips.
Functions for Cotton (Gossypium hirsutum L.) Production from Irrigation and Nitrogen Fertilization Variables: I. Yield and Evapotranspiration1
Authors: Grimes Donald W. , Yamada H. , Dickens W. L. 
Published: July 2010

AbstractCotton lint yield, evapotranspiration (ET), and efficiency of water use were characterized with 2nd‐degree polynomials as functions of the quantity of irrigation water and nitrogen applied on two widely different soils. Excessive vegetative plant development at high input levels of irrigation water and nitrogen resulted in production functions for lint yield having negative interaction coefficients. By placing lint yield on a relative basis for the two soils, it was possible to express relative yield as a function of ET with a single quadratic regression equation (R. Y. = −266.4 + 10.72(ET) −0.079(ET)2;R2 = 0.78). Total seasonal ET increased at a decreasing rate with increased water application up to an addition of 119 cm of water during the entire growing season. Peak daily rates of soil moisture depletion were 1.07 cm, occurring near the time when maximum leaf area was attained. Water use efficiency (kg lint per cm of water used) was improved, in some cases, with the addition of nitrogen.
Functions for Cotton (Gossypium hirsutum L.) Production from Irrigation and Nitrogen Fertilization Variables: II. Yield Components and Quality Characteristics1
Authors: Grimes Donald W. , Dickens W. L. , Anderson W. D. 
Published: July 2010

AbstractSecond‐degree polynomials were used to characterize direct yield components, plant height, and certain quality characteristics of fiber as dependent variables on waterand N‐supplied cotton plants. Yield was correlated most highly with the number of flowers and bolls produced.Yield was correlated positively with plant height (as a measure of plant growth) when all data were considered, but correlated either positively or negatively when only part of the response function was considered.Fiber length, micronaire, strength, and elongation were influenced more by water supply than by nitrogen.
Initial Competition of Root‐nodule Bacteria on Soybeans in a Field Environment1
Authors: Caldwell B. E. 
Published: July 2010

AbstractCompetitive behavior of three strains of Rhizobium japonicum was evaluated in a soil free of this organism. The three strains differed in their competitive ability. Strain 110 produced 98% of the nodules when applied in combination with strain 38, and 76% when in combination with strain 76. Strain 76 produced 95% of the nodules when applied in combination with strain 38. Results from treatments inoculated with the individual strains indicated that strain 110 produced the greatest fresh weight and greatest bean yield.
Short Wave Radiation on Inclined Surfaces in Model Plant Communities1
Authors: Anderson Margaret C. , Denmead O.T. 
Published: July 2010

AbstractThe paper describes methods for easy calculation of the flux densities of direct and diffuse radiation on inclined foliage in model plant stands. The stands are composed of randomly oriented, constantly inclined, flat foliage surfaces. The calculations require knowledge of the flux densities of direct and diffuse radiation on a horizontal surface above the stand, foliage inclination, foliage area index, and solar altitude.For direct radiation, the effects of changes in foliage inclination angle on the average radiation receipt by the foliage depend strongly on solar altitude and on season and time of day. Relatively large differences can exist between stands of different foliage inclination. The distributions throughout the day of direct radiation on inclined foliage surfaces in the stand are shown to be quite different from those on horizontal surfaces.There are only small differences between surfaces of different inclination in the receipt of diffuse radiation, particularly at the top of the stand.Trial calculations suggest that in the agricultural growing seasons of many temperate regions the daily receipt of direct radiation by the foliage of a stand per unit of ground surface will increase with foliage inclination.Some problems of modelling energy‐dependent plant processes in stands are discussed.
Differential Response of Cotton and Peanuts to Subsoil Acidity1
Authors: Adams Fred , Pearson R. W. 
Published: July 2010

AbstractA series of experiments was conducted to compare the effects of subsoil acidity on cotton (Gossypium hirsutum L.) and peanuts (Arachis hypogaea L.). A strongly acid (pH 5.0) Norfolk sandy loam subsoil reduced cotton yield by one‐third in a field experiment but had no detrimental effect on peanut yield. Cotton roots were unable to penetrate the most acid subsoil in this experiment, whereas peanut roots appeared to be undaunted by the acidity. Growth‐chamber experiments with acid Norfolk and Greenville subsoil materials showed cotton root‐growth to be almost completely inhibited by soils that had no apparent detrimental effect on peanut roots Nutrient‐solution experiments showed that cotton roots created a more acid root environment than did peanuts; these experiments also showed that peanuts had a greater propensity for preferential absorption of lower valency ions to the exclusion of higher valency ions. Either or both of these phenomena could explain the greater tolerance of peanuts to low soil pH and its associated high soil solution aluminum.
Influence of Leaf Age, Illumination, and Upper and Lower Surface Differences on Stomatal Resistance of Sugar Beet (Beta vulgaris) Leaves1
Authors: Brown K. W. , Rosenberg Norman J. 
Published: July 2010

AbstractStomatal diffusion resistances of sugar beet leaves were calculated from measurements made on photomicrographs of leaf impressions. The impressions were made by spraying a rapid drying acrylic resin on the leaf.Milthorpe and Penman's (1967) method for calculating stomatal resistances was programed for electronic computer. Resistances were calculated for leaves of different physiological age and for shaded and sunlit leaves. Calculations were also made separately for upper and lower surfaces of selected leaves. Despite the continuous expansion of the sugar beet leaf throughout its life, the Stomatal resistance of similarly exposed leaves was independent of physiological age except for the most immature leaves.The greater values of stomatal resistance found for older leaves in the lower part of the canopy were attributed to microclimatic differences, including reduced illumination, rather than to changes associated with advancing physiological age.
Water Storage and Drainage under a Row Crop on a Sandy Soil1
Authors: Black T. A. , Gardner W. R. , Tanner C. B. 
Published: July 2010

AbstractDrainage from the root zone of snap beans grown on a sandy soil was measured by a lysimeter, and calculated from Darcy's law, and by a hydrologic balance equation. At the end of a 60‐day period the Darcy's law calculation gave a 11% higher estimate of the cumulative drainage than the other two methods. Of the 32 cm of precipitation and decrease of 3 cm in water storage from emergence to harvest, evapotranspiration accounted for 17 cm, and drainage for 18 cm. A useful estimate of the drainage from the root zone in sandy soil was obtained from the space averaged capillary conductivity of the soil in which rooting occurred.
Growth, Composition, and Metabolic Responses of Sugar Beet to Preharvest Application of Maleic Hydrazide1
Authors: Wort D. J. , Singh B. 
Published: July 2010

AbstractMaleic hydrazide, 8 × M−3, was applied to the foliage of mature plants of sugar beet (Beta vulgaris L.). Its effects on growth and various aspects of composition and metabolism were determined 7, 14, and 21 days after treatment. The striking result was a significant curtailment of growth of leaves and an increase in sucrose content of the storage root. Maximum inhibition of leaf growth, 66%, was evident 7 days after treatment. The sucrose content of the roots was significantly larger on all three days of measurement, while protein and total N were considerably less. Higher nitrate and lower nitrite contents paralleled a decrease in the activity of nitrate reductase.Respiration in both leaves and roots was depressed, but the photosynthetic rate was greater by 49%, 21 days after treatment. The activity of nitrate reductase and transaminase in leaf and root fell 40% and 18% below values in control plants by the 21st day following treatment. Invertase activity was significantly reduced. The activities of glucose‐1‐, glucosed‐, and fructose‐6‐phosphatases; phenyl phosphatase; and ATPase were depressed by treatment. On the other hand, the activities of the enzymes of sucrose biosynthesis, UDPG‐pyrophosphorylase, sucrose synthetase, and sucrose phosphate synthetase, were significantly stimulated.The responses suggest that “ripening” may be induced and that the late autumn growth, which often occurs at the expense of stored sucrose, may be considerably reduced by the foliar application of maleic hydrazide 7 to 21 days before the sugar beets are to be dug.