bluuebunny/crossref_metadata_2025_split huggingface dataset:
Yield, Regrowth, and Persistence of Sainfoin under Fertilization1
Authors: Meyer D. W. 
Published: July 2010

AbstractSainfoin (Onobrychis viciaefolia Scop.) forage yields frequently are inferior to alfalfa (Medicago sativa L.) where seasonal rainfall is adequate due to sainfoin's poor regrowth and plant vigor. Inoculated sainfoin plants typically show nitrogen deficiency symptoms at Fargo, N. Dak.; therefore, N, P, and K were applied broadcast on a 3‐year‐old, inoculated ‘Eski’ stand attempting to reduce deficiency symptoms, stimulate substantial regrowth, and thereby yield.N increased sainfoin's weed‐free forage yield during the third and fourth harvest years for each increment applied up to 448 kg/ha. Plants vigor and regrowth, as indicated by aftermath harvest, was enhanced by N fertilization. Stand persistence was poor for all treatments except 448 kg N/ha. Sainfoin forage yields do not compare favorably with the third and fourth harvest year productivity of unfertilized, inoculated alfalfa even when fertilized with 448 kg N/ha. Phosphorus and K treatments, alone or in combinations with N, had little detectable influence on yield, recovery, or stand persistence.
Effect of Liming a Highly Al‐saturated Soil on the Top and Root Growth and Soybean Nodulation1
Authors: Sartain J. B. , Kamprath E. J. 
Published: July 2010

AbstractRelatively little information is available on the effects of liming on roots as compared with tops. To study the effect of various Al saturations on the growth of tops, roots, nodules, and nutrient accumulation of soybeans (Glycine max L.), several rates of lime were added to an acid soil in a greenhouse experiment. Dry weight of tops increased as the Al saturation was decreased by liming. Total dry weight and length of roots were unaffected by the soil treatments. Primary root weight was increased by liming. Root morphology, however, changed in that the lateral root weight decreased and the length per gram fresh weight of lateral root increased with decreasing Al saturation. Liming promoted the formation of a larger number of small diameter lateral roots. Nodulation, best expressed by nodule number, increased with liming and was highly correlated with the Ca content of the primary root.Top dry weight was significantly correlated with the K concentration of the tops, Ca and Al concentration of the nodules, Mg concentration of the root mass, and the Zn concentration of the primary root. Total uptake/cm of root and equivalent elemental ratios were not as highly correlated with growth as concentration. Nodule number was significantly correlated with the total Ca and P content of the primary root, total P and Mg content of nodules, and the Ca/Al ratio of the nodule.
Soil Water Extraction by Alfalfa1
Authors: Brun L. J. , Worcester B. K. 
Published: July 2010

AbstractSaline seeps have developed because of the accumulation of water beyond the rooting zone of annual crops. The purpose of this experiment was to show the potential of alfalfa (Medicago sativa L.) to extract soil water under a variety of textural and salinity conditions. Soils examined belong to suborders Ustoll and Boroll.Core samples were taken in alfalfa fields and fields under crop‐fallow management to evaluate their present water content, 15 atm. percentage, texture, and salinity level.Significant extraction of soil water occurs to depths of 3 to 4 m. Alfalfa extracted soil water held at a tension greater than 15 atm. in both saline and non‐saline segments of the soil profile. A minimum soil moisture level was reached at the 1.22 to 2.44 m depth in alfalfa fields maintained 5 years.Alfalfa is an invaluable crop for reducing soil wetness to alleviate the saline‐seep problems of western North Dakota and eastern Montana.
Effects of Organic Preservatives on the Quality of Aerobically Stored High Moisture Baled Hay1
Authors: Sheaffer C. C. , Clark N. A. 
Published: July 2010

AbstractAerobic storage of hay at high moisture levels results in losses of forage quality due to microbial growth. Yet, the determination of safe forage moisture levels in the field is difficult, and farmers also must often store hay at above optimum moisture levels in order to avoid losses due to inclement weather. Two experiments were conducted in which propionic acid and ammonium isobutyrate were manually applied to high moisture alfalfa‐timothy (Medicago sativa L. ‐ Phleum pratense L.) hay in order to evaluate their effectiveness in preventing mold growth. Rates of preservative application for hay baled at 31% moisture content were: O, 1.00, 1.50, 1.75, and 2.00% by weight; for hay baled at 40% moisture content, rates were: O, 2.00, 3.00, 4.00, and 5.00%. Temperatures were monitored and in vitro digestibility (IVDMD), acid detergent fiber (ADF), and acid detergent insoluble N (ADIN) were determined.There were no significant differences in the preserving effects of the two compounds; however, there were significant differences in rates necessary to preserve the hay at a given moisture level. Hay baled at a moisture content of 31% and treated with preservatives at rates of 1.50 to 2.00% had significantly lower storage temperatures and significantly higher IVDMD than untreated hay and hay sprayed at the 1.00% rate. Rates of application of 3.00 to 5.00% were effective in significantly reducing storage temperatures and maintaining forage quality of hay baled at 40% moisture.Propionic acid and ammonium isobutyrate can effectively preserve high moisture aerobically stored hay. Rates of application must be based on the moisture content of the hay at the time of baling.
Ultraviolet Radiation Reflectance, Transmittance, and Absorptance by Plant Leaf Epidermises1
Authors: Gausman H. W. , Rodriguez R. R. , Escobar D. E. 
Published: July 2010

AbstractPartial destruction of ozone in the earth's upper atmosphere (stratosphere) will increase levels of ultraviolet (UV) radiation that reach the earth's surface; consequently, plants could be exposed to harmful amounts of UV‐B radiation (280 to 320 nm). The objective of our research was to characterize the reflectance, transmittance, and absorptance of UV‐B radiation by leaf epidermises. Accordingly, measurements were made spectrophotometrically over the 260 to 360‐nm wavelength, to encompass the UV‐B waveband, on epidermises of different thicknesses from six plant genera: Century plant (Agave americana L.), onion bulb (Allium cepa L.), peperomia (Peperomia obtusifolia A. Dietr.), yucca (Yucca treculeana Carr.), kalanchoe (Kalanchoe laciniata DC.), and pricklypear (Opuntia lindheimeri Engelm.).Thick epidermises of pricklypear, peperomia, century plant, and yucca reflected and transmitted less and absorbed more UV radiation over the 260 to 360‐nm waveband than thinner epidermises of onion and kalanchoe. Absorptance of the critical UV‐B radiation ranged from 91 to 96% for the thick epidermises and from O to 66% for the thinner epidermises.It is concluded that leaves of plants with thick epidermises would have less internal damage to inner tissues of their mesophylls by UV‐B radiation than leaves with thinner epidermises; however, UV‐B radiation may damage the epidermis itself.
Yield Response to Soil Warming: Vegetable Crops1
Authors: Rykbost K. A. , Boersma L. , Mack H. J. , Schmisseur W. E. 
Published: July 2010

AbstractWaste heat appears in the form of warm condenser cooling water from power generating plants. It has been proposed to use this water with temperatures ranging from 25 to 40 C for warming soils by pumping it through buried pipes. Experiments were conducted to determine the effect of warming soils in this manner on the growth rates and yields of several crops. The proposed system was simulated with electrical heating cables buried 92 cm deep at a spacing of 183 cm. Heat source temperatures ranged from 35 to 38 C during the growing period. Heating increased the average temperature of the soil layer from O to 100 cm deep by about 10 C. The average temperature increase of the O to 10 cm depth soil layer was μ 3 C. The crops tested were bush beans (Phaseolus vulgaris), lima beans (Phaseolus lunatus), tomatoes (Lycopersicmi esculentum), broccoli (Brassica oleracea), peppers (Capsicum annuum), and strawberries (Fragaria virginiana).The yield increases, expressed as percentages of yields obtained on unheated plots, ranged from 19% for bush beans to about 100% for broccoli. The greatest advantage gained from soil warming occurred early in the growing season. The advantages decreased as the season progressed. The plants continued to grow fastest on heated plots throughout the growing periods however. Soil warming sustained growth rates of bush beans in the early fall when plants on unheated plots were slowed in growth. A wide variation in yield responses occurred between different years for the same crop and between different crops during the same year. The highest yield increases occurred during years when the yields on unheated plots were lowest. Correlations between yield increases and yields from unheated plots were highly significant.
Moisture Absorption, Mold Growth, and Decomposition of Rice Straw at Different Relative Humidities1
Authors: Sain Pritam , Broadbent F. E. 
Published: July 2010

AbstractMoisture and humidity relationships of rice straw are important in relation to the extent of decomposition that may occur during the winter season. Ground rice straw was exposed to constant relative humidities to measure moisture absorption, decomposition, and mold growth. Moisture absorption by rice straw was very rapid during the first few hours and approached equilibrium within 1 to 4 days depending upon the relative humidity. Moisture content at equilibrium at a given relative humidity was always greater at 8 than at 25 C. The relation between moisture absorption and relative humidity above 70% followed a parabolic function of the form M = a + bR + cR2 where M = % moisture, R = relative humidity, and a, b and c are constants. The rate and extent of straw decomposition were found to increase and the lag period of decrease with increasing relative humidity and temperature. The transition between slow and active decomposition of rice straw was at about 90% relative humidity. The threshold moisture content of rice straw for mold growth, defined as the highest moisture content at which it takes infinite time for the initiation of fungal growth, was found to be 7.5%.
Nutrient Uptake by Russet Burbank Potatoes as Influenced By Fertilization1
Authors: Jackson T. L. , Carter G. E. 
Published: July 2010

AbstractZinc and Mn deficiencies have been observed frequently in potatoes grown on eastern Oregon soils developed under arid conditions. The study was designed to evaluate effects of band and broadcast applications of ammonium sulfate (AS) and monocalcium phosphate (MCP) on yield and uptake of P, Zn, and Mn by Russet Burbank potatoes (Solanum tuberosum L.) grown on calcareous mineral soil deficient in N, P, Zn, and Mn.Potatoes were grown under field conditions, harvested and evaluated. Fertilizer treatments were broadcast before planting and rototilled or banded at planting. Petiole samples to identify nutrient concentrations were taken when tubers were 2 cm in diam. Whole plants were harvested 3 weeks later to measure nutrient uptake.Petiole concentrations and plant uptake of both Zn and Mn were greater when AS was banded than when broadcast, with or without band applications of Zn and Mn.Highest P concentrations were found on check plots or when P alone was applied. Treatments producing increased Zn concentrations in plants were associated with reduced P concentrations. Banded AS with or without Zn and Mn produced the largest yield increase but resulted in reduced P uptake. Increased P uptake occurred only after Zn and Mn deficiencies were corrected. Moderate increases in uptake of Zn and Mn resulted from banding of MCP, Zn, and Mn.
Nitrogen Uptake Characteristics of Corn Roots at Low N Concentration as Influenced by Plant Age1
Authors: Edwards J. H. , Barber S. A. 
Published: July 2010

AbstractInformation is needed on the relation between concentration of N in solution, CN, and the rate of N uptake by corn (Zea mays L.) roots in order to evaluate the soil and crop parameters affecting N fertilizer efficiency. Data on net N influx, In, vs. CN were obtained for N levels below 150 μM on corn plants of seven ages ranging from 15 to 58 days (2 weeks after tasseling). In was determined by measuring rate of N depletion from the solution in which corn plants grew. Both NH+4 and NO‐3 forms of N were used. The experiments were conducted in the growth chamber and greenhouse.Maximum influx, In‐max, occurred above 21 μM N concentration. Values of In‐max, varied with plant age and were greatest with 18 to 24‐day‐old plants and decreased exponentially to 58‐day‐old plants. In ceased when the averaged CN value decreased to 4 μM. This minimum N concentration varied little with plant age. Since the range of CN values where In varied was only 4 to 21 μM, the time period when CN is within this range for corn growing in the field is probably short so In will usually be at either In‐max or 0.
Response of Cotton to Row Patterns and Plant Populations1
Authors: Baker Shelby H. 
Published: July 2010

AbstractTheoretically, cotton planted in narrow rows at high plant populations has a potential of reducing production cost by promoting earlier maturity. The cost of controlling insects, weeds, and harvest due to a once‐over harvest would all be reduced.Studies were conducted to determine how a cultivar developed for conventional production methods would respond to a narrow row system. Coker 310 was planted in conventional 91.4 cm rows at a population of 107,489 plants/ha, in four 40.6 cm rows on a 182.9 cm bed and in twin 25.4 cm rows on a 91.4 cm bed at populations of 214,977; 286,636; and 358,295 plants/ha for 3 years.There were no differences in yield, earliness, lint percent, fiber length or strength between narrow row and the conventional check. The conventional check produced larger bolls, fewer blooms, a lower potential yield and set a higher percent of early blooms.Narrow rows gave no differences in total yield, earliness, lint percent, fiber length, or strength resulting from row patterns or plant populations. The highest plant population gave more blooms in twin 25.4 cm rows, but not in 40.6 cm rows. Potential yield was not influenced by population within row patterns, but there was a row pattern response at the same plant population.Boll size tended to be inversely related to plant population. The highest plant population in the 40.6 cm rows produced a finer fiber than other treatments.This study indicates the potential of high population — narrow row planting is lost mainly through excessive shedding of young bolls during the first 3 weeks of blooming.
Water Vapor Sorption by the Walls and Sensors of Stomatal Diffusion Porometers1
Authors: Gandar P. W. , Tanner C. B. 
Published: July 2010

AbstractThe operation of stomatal diffusion porometers is affected by sorption of water vapor by the humidity sensor and the walls of the porometer. The objective of this study was to assess the amount of water vapor sorbed by Dunmore lithium chloride humidity sensors and by materials commonly used in porometer construction. Measurements of water sorption by stainless steel, acrylic plastic, wax‐coated acrylic, and humidity sensors were made at different relative humidities (RH) in the range of 22 to 28% RH and temperatures of 20, 25, and 30 C, by measuring the vapor mass balance at different RH. Stainless steel absorbed 0.5 ± 0.25 μg cm−2 of water vapor at 22 to 28% RH and temperatures from 20 to 30 C. Water vapor diffused into acrylic (D ≈ 2.5 × 10−9 cm2sec−1) so the sorption was not constant. Coating acrylic with wax significantly reduced water sorption; at 25 C the sorption of waxed acrylic was in the range 0.9 to 1.2 μg cm−2. The sorption by the humidity sensors varied with RH, temperature, sensor age, and prior treatment. At 25 C and 26% RH the sorption of the external sensor surface was about 40 μg cm−2. Materials with low sorptivities, such as stainless steel or waxed surfaces, should be used in the construction of diffusion porometers. Procedures which minimize variability in sorption, such as storage at RH near the operating range of the sensor, should be followed when porometers are used.
Effect of Fertilizer‐N and Herbicides on the Growth and N Content of Sunflower1
Authors: Sameni A. M. , Maftoun M. , Hojjati S. M. , Sheibany B. 
Published: July 2010

AbstractLittle is known about herbicide‐N fertilizer combinations with respect to the growth and mineral composition of sunflower (Helianthus annuus L.). The present study was undertaken to evaluate the effect of prometryn (2,4‐bis(isopropylamino)‐6‐(methylthio)‐s‐triazine), terbutryn (2‐(tert‐butylamino)‐4‐(ethylamino)‐6‐(methylthio)‐striazine), trifluralin (α,α,α‐trifluoro‐2,6‐dinitro‐N,N‐dipropyl‐p‐toluidine), and N level on the growth and N uptake by this crop. Sunflower was grown in greenhouse for 60 days in soil to which was added various levels of N and herbicides. Dry matter yields, N concentration and N uptake were determined. Low N levels significantly increased stem diameter and chlorophyll content of leaves as compared to the no N level. Nitrogen application above 25 ppm did not increase stem diameter. All N‐treated plants produced more dry matter and contained significantly higher N than untreated seedlings. Prometryntreated seedlings developed chlorotic symptoms, causing plant death. Nitrogen uptake increased with 1 ppm terbutryn, but 2 ppm terbutryn increased N concentration and uptake but decreased plant height, stem diameter, chlorophyll content, and total plant weight of sunflower. The tendency for terbutryn to increase N concentration was more pronounced when sunflower was under N stress. Trifluralin did not significantly increase top dry weight or N uptake, nor did it interact with N treatments.
Infinite Reflectance of Dead Compared with Live Vegetation1
Authors: Gausman H. W. , Rodriguez R. R. , Richardson A. J. 
Published: July 2010

AbstractThe objective was to compare the infinite reflectance (R∞) of dead and live corn (Zea mays L.) leaves over the 0.5‐ to 2.5‐μm waveband to find a means of distinguishing live from dead vegetation for remote sensing purposes; previous studies have been concerned only with R∞ of live leaves. In this study, for both dead and live leaves, reflectance measurements were made on a single leaf seciton and for sections stacked two, three, four, five, six, seven, and eight at a time over a spectrophotometer's port. Live leaf R∞ was essentially attained by stacking two leaves for the 0.5‐ to 0.75μm waveband (chlorophyll absorption region), eight leaves for the 0.75‐ to 1.35‐μm waveband (near‐infrared region), and three leaves for the 1.35‐ to 2.5‐μm waveband (water absorption region). Dead leaf R∞ was reached over the entire 0.5‐ to 2.5‐μm waveband by stacking only two or three leaves. Thus aircraft and spacecraft reflectance measuring techniques probably cannot distinguish density differences of dead vegetation but they should distinguish density differences of live vegetation. Near‐infrared reflectance differences between dead and live vegetation also should be detectable with satellite multispectral scanner data.
Water Transport in Wheat Plants in the Field1
Authors: Denmead O. T. , Millar B. D. 
Published: July 2010

AbstractMost previous studies of water transport in crops have been based on simplified models of plant anatomy and canopy transpiration. Usually changes in the water potential of a particular leaf have been related to the water loss from the whole canopy. We present a more detailed analysis of plant water transport which accounts for the spatial distribution of water flows and transpiration losses throughout the canopy, and use it to estimate flow resistances in different segments of the pathway.Micrometeorological measurements of the flux densities of water vapor in the canopy were used to infer water fluxes through roots, stem sections, leaves, and ears of wheat plants (Triticum aestivum L. ‘Heron’) in the field. Simultaneous measurements of soil‐ and leaf‐water potentials permitted calculation of flow resistances in roots, stems, and leaves.There were no significant differences in resistances between an irrigated and a dryland crop, although the patterns of stem flow differed markedly. The resistance of the root system of an individual tiller was (1.00 ± 0.37) × 10' bar sec cm‐3 and the resistance/unit length of stems and leaves was (1.59 ± 0.19) × 103 bar sec cm‐4. These large plant resistances may often be as important in determining leaf water potentials as the transmission resistance of the soil. The study shows clearly how the water loss from one part of the canopy influences the development of water potentials in other parts and points up the difficulties of simplified transport models.
Water Relations of Wheat Leaves in the Field1
Authors: Millar B. D. , Denmead O. T. 
Published: July 2010

AbstractStomatal closure at low leaf turgor and water potentials has been demonstrated in a number of crop plants but as far as we are aware, the magnitudes of these critical potentials have not been established for temperate cereals; nor have their variation from one leaf to the next been studied. We have examined the relationships between turgor potential (P), water potential (Ψ), osmotic potential (π), and stomatal closure in leaves at different positions on the stem of mature wheat plants (Triticum aestivum L. ‘Heron’) in the field.Thermocouple psychrometry was used to determine P, Ψ, π, and the resistances of leaves to mass‐flow were used as an indication of stomatal aperture.Stomatal closure was induced at about the same P, 8 bars, in leaves at all positions on the stem, but because of a different relationship between and Ψ for each leaf, the corresponding critical water potentials varied from —7 bars for leaves at the bottom of the stem, to —14 bars for the next highest leaves, to —19 bars for top leaves. The different relationships between P and Ψ resulted from a systematic decrease in π with leaf position from bottom to top of the stem.There appear to be important differences in leaf water relations between this wheat variety and some other crops. For instance, the critical P of 8 bars is higher than has been reported for maize, sorghum, and tobacco, but π is generally lower. The agronomic significance of these species differences is discussed.
Sulfur Response of Maize in Western Nigeria1
Authors: Kang B. T. , Osiname O. A. 
Published: July 2010

AbstractStudies of S deficiency, a problem in certain crops in Africa, have yielded inconclusive and incomplete information. There is little information on the S status of soil in the forest‐savanna zone.Field trials were carried out with maize (Zea mays L.) at six locations in the forest and savanna zones of western Nigeria. Sulfur was applied at 0, 7.5, 15.0, 30.0, and 60.0 kg S/ha. Significant yield increases were observed with rates of S application from 7.5 to 30 kg S/ha. The response was more distinctly evident in the savanna than in the forest zone. Silking percentage was enhanced and grain quality improved with S application. No significant residual effect of the applied S was observed in the savanna zone, which was probably due to heavy leaching of the applied S. On these soils S response was observed where the amount of extractable S, extracted with either KH2PO4, Ca(H2PO4)2, or NH4C2H3O2 was below 4 ppm S. There was no response to S when extractable S levels were equal to or greater than 8.5, 10.0, and 12.0 ppm when soils were extracted with Ca(H2PO4)2, NH4C2H3O, and KH2PO4, respectively. The critical S level in the ear leaf was estimated at about 0.14% S. Although there was a strong correlation between % N and % S in the ear leaf, the N:S ratio was not related to critical S levels in plants.