bluuebunny/crossref_metadata_2025_split huggingface dataset:
Results of Changing Light and Temperature Regimes in a Corn Field and Temperature Effects on the Apparent Photosynthesis of Individual Leaves1
Authors: Winter S. R. , Pendleton J. W. 
Published: July 2010

AbstractIrrigated, heavily fertilized corn (Zea mays L.) was grown in varying light and temperature regimes at Urbana, Ill., in 1967. The corn plants were subjected, during certain developmental stages, to a light and temperature “rich” field environment created with large aluminum reflectors. In addition, the effects of temperature on apparent photosynthesis were studied.Light and temperature (“radiation”) enrichment greatly increased grain yields. Per plant grain yields for a normal planting, a border row planting, and three “radiation rich” border row plantings (radiation rich from 1.5 m tall to pollination, pollination to maturity, and 1.5 m tall to maturity) were 42.4, 173.7, 206.8, 249.5 and 265.8 g/plant, respectively. Plants in a radiation rich regime, which were cooled by a water mist whenever the air temperature exceeded 29.4 C, yielded 22.2 g/plant (243.6 vs. 265.8 g/plant) less than radiation rich uncooled plants. Therefore, part of the yield increase in the radiation rich regime is apparently due to the increase in temperature caused by the additional radiation.Investigations of the effect of temperature on the apparent photosynthesis of attached ear leaves in bright sunlight near solar noon indicated optimum leaf and air temperatures of 40.5 and 32 C, respectively. The optimum temperature under ordinary field conditions might well be lower due to any one of several environmental limitations such as inadequate light, water stress, or perhaps inadequate carbon dioxide.
Influence of Nitrogen and Potassium Fertilizers and Dates of Seeding on Yield and Quality of Malting Barley1
Authors: Zubriski J. C. , Vasey E. H. , Norum E. B. 
Published: July 2010

AbstractThirteen field trials were conducted to test the effects of rates of N and K fertilizers and seeding dates differing by 2 weeks upon yield, percentage plump kernels, and protein content of malting barley. N fertilizer increased average grain yields on early‐seeded plots by 253, 410, and 534 kg/ha for 22.4, 44.8, and 67.2 kg N/ha, respectively. On late‐seeded plots, same rates of N increased average yields by 264, 303, and 389 kg/ha, respectively. Late seeding reduced average grain yields by 295 kg/ha. Rates of 14 and 28 kg K/ha increased average grain yields by 42 and 48 kg/ha, respectively, on early‐seeded plots and by 71 and 81 kg/ha, respectively on late‐seeded plots. N did not affect average percentage of plump kernels but 14 and 28 kg K/ha increased percentage plump barley by 1.3 and 1.7 percentage units on early‐seeded plots and by 1.8 and 2.7 percentage units on late‐seeded plots, respectively. Late seeding reduced the percentage of plump kernels by 9.8 percntage units. The average protein content of grain was 12.8, 13.1, 13.2, and 13.5% on early‐seeded plots and was 13.4, 13.6, 13.9, and 14.2%percent on late‐seeded plots for O, 22.4, 44.8, and 67.2 kg N/ha, respectively. Late seeding increased the average protein content by 0.7 percentage units. K reduced the average protein content by 0.1 percentage unit on both early and late‐seeded plots.
SeLection of an Alfalfa Plant Part for Phosphorus Analysis1
Authors: Chambliss C. G. , Miller D. A. , Jackobs J. A. 
Published: July 2010

AbstractThe objective of this study was to find an alfalfa (Medicago sativa L.) plant part that (1) has low variability in phosphorus concentration, at a given level of available phosphorus, from one sampling to the next throughout the growing season, and (2) also adequately reflects differences between phosphorus treatments. Alfalfa plant samples were collected from field plots which had been topdressed with different levels of phosphorus. The samples were collected on nine different dates at various stages of maturity in 1966 and 1967. After collection the samples were separated into five plant parts consisting of top leaves, mid‐leaves, top stems, mid‐stems, and bottom stems. The mid stems consistently showed greater sensitivity to phosphorus treatments and had less variation across sampling dates than the other plant parts. Therefore the mid‐stem was considered to be the most suitable plant part to use in determining the phosphorus status of alfalfa.
Calcium and Strontium Relationship in Various Commercially Important Plants1
Authors: Creger C. R. , Holt E. C. , Lovelace D. A. 
Published: July 2010

AbstractThe rate of uptake and the degree of translocation of strontium was investigated, as well as the amounts taken up and the effects on the growth of sorghum, cotton, and bean plants when high levels of strontium are incorporated into the culture medium. Strontium was shown to be taken up readily by the plants and also to be very mobile in actively growing plant tissue. Species differed in growth response to Sr with the greatest retarding (toxicity) effect occurring with bean plants. Species showing the largest percent of Ca in plant tissue in a Sr‐free culture showed the largest concentration of Sr in a Ca‐free culture. Generally, the Sr content of plant tops was higher than roots at all Ca/Sr ratios in the culture solution.
Nitrogen Nutrition and Growth Relations of Tall and Intermediate Wheatgrasses1
Authors: Hylton L. O. , Cornelius D. R. , Ulrich A. 
Published: July 2010

AbstractAlkar tall wheatgrass, Agropyron elongatum (Host.) Beauv., and Greenar intermediate wheatgrass, A. intermedium (Host.) Beauv., grown separately in nutrient solutions to which NO3‐ had been added at 0, 0.25, 0.5, 1.0, 2.0, 4.0, 8.0, 16, or 32 meq of NO3‐ per liter. Other nutrients were present in ample amounts. The two grasses were grown concurrently in full greenhouse sunlight for 36 days. Total dry matter production (tops + roots) was significantly reduced with less than 4.0 meq of NO3‐ per liter. Average maximum top weight (oven‐dry) was 2.02 g per plant for tall wheatgrass and 2.76 for intermediate wheatgrass. These top weights were obtained with 8, 16, or 32 meq of NO3‐ per liter. In a common and favorable environment, growth of intermediate wheatgrass was more rapid than that of tall wheatgrass.Accumulation and distribution of nitrate‐N varied slightly within the plants. At high NO3‐ treatments, matured blades of tall wheatgrass had the highest nitrate‐N concentration (14,600 ppm) whereas stems of intermediate wheatgrass had the highest (16,000 ppm) concentration. Immature blades had the lowest nitrate‐N concentration, about 8,200 and 9,200 ppm, respectively, for tall and intermediate wheatgrasses. Recently matured blades of intermediate wheatgrass had higher percentages of total‐N, nonsoluble‐N (protein‐N), and crude protein than did those of tall wheatgrass. Soluble‐N and nitrate‐N concentrations were generally higher in tall wheatgrass than in intermediate wheatgrass.The critical nitrate‐N concentrations for growth of these two wheatgrasses is about 500 ppm nitrate‐N in recently matured blade tissue, dry basis.
Prediction of the Nitrogen Requirements of Field Crops Part I. Theoretical Models of Nitrogen Release1
Authors: Reuss J. O. , Geist J. M. 
Published: July 2010

AbstractTheoretical models for the prediction of the total supply of mineral nitrogen available for crop production have been developed. These models are based on the assumption that the supply of available N is determined by fertilizer N, native soil mineral N, and N released from organic matter. Model No. [1] is of the form Y = b0 + blXl + b11X12 + b2X2 + b22X22 + b12X1X2, where: Y = yield or other parameter dependent on N supply, Xl = fertilizer N plus available soil mineral N, X2 = any index of organic N release, and bl, b2, b . . . are coefficients determined by regression techniques. Model No. [2] is of the form Y = B0 + B1(X1 + aX2) + B2(X1 + aX2)2, where: a represents a release coefficient appropriate to a given X2; B0, B1, B2 are regression coefficients; and Y, X1, and X2 are the same as in Model [1]. The release coefficient a can be evaluated by ratios of coefficients from Model [1], ratios of slopes from Model [1], or by a reiterative procedure. More sophisticated models based on Model [2], but assuming nonlinear release of organic N, have also been developed along with methods for evaluating the constants involved.
Prediction of Nitrogen Fertilizer Requirements of Field Crops. II. Application of Theoretical Models to Malting Barley1
Authors: Geist J. M. , Reuss J. O. , Johnson D. D. 
Published: July 2010

AbstractFive indices of soil organic nitrogen availability and mineral plus fertilizer nitrogen were used in the prediction of grain yield, grain protein content, and grain protein nitrogen of Moravian barley. Three mathematical models were employed, one of which included only soil mineral plus fertilizer N for prediction of crop parameters. The remianing two models, which included both organic and mineral plus fertilizer N showed improved predictability of crop parameters. No organic nitrogen measure showed superiority to others, however, one equation model was advantageous in studying the relative contribution of soil organic N to crop production.
Effect of Seedbed Preparations and Green Manure Crops on Corn (Zea mays) Production1
Authors: Beaty E. R. , Giddens Joel 
Published: July 2010

AbstractFour cover crop treatments consisting of (A) fallow, (B) rye, (C) crimson clover, and (D) rye and crimson clover were seeded to corn on seedbeds prepared by (a) conventional plowing and disking, (b) disking, (c) remove cover crops‐direct seed, (d) cover crop mulched‐direct seed and (e) plant‐mulch cover crop. Corn yields ranged from 4,638 kg/ha on fallow soil to 4,912 kg/ha following crimson clover. Corn yields varied from 4,510 kg to 5,005 kg/ha with different seedbed preparations. The plowed and disked seedbed produced the highest corn yield followed closely by the disked and mulched‐planted seedbeds. Seedbeds where the green manure crop was removed before planting or mulched after planting produced the lowest average yields.In Georgia green manure crops and seedbeds appear to contribute little to corn production that cannot be obtained by application of commercial fertilizers, and the use of green manure crops would depend upon secondary use of the cover crop.
Jaw‐Action Soil Crusher1
Authors: Reisenauer H. M. , Willett Norman F. 
Published: July 2010

AbstractA jaw‐action soil crusher is described that crushes and screens soil with minimum contamination, dust production, and operator effort. The machine is suited to samples of greater than 1 liter volume and yields up to 10 kg of 11‐mm mesh soil, or lesser amounts of finer soil, per minute.
Effect of Placement of Phosphorus and Lime on the Growth of a Ladino Clover‐Orchardgrass Sward1
Authors: Woodhouse W. W. 
Published: July 2010

AbstractHigh exchangeable Al in subsoils has been suspected as a cause of limited persistence of ladino clover on some soils of the Southeast. The effect on a ladino‐orchardgrass sward of rather thorough incorporation of P and limestone into one such soil was studied. Mixing was by means of a rototiller, one furrow at a time, and extended as deep as 45 cm, compared with broadcast application, followed by disking to 15 cm. Two levels of each material were used, the soil test suggested level and 3 times the soil test level. Deep incorporation resulted in no detectable benefit with either material, and appeared to reduce residual P. Subsoil Al was sharply reduced by liming, but it appeared that mixing to a depth of 15 cm was adequate for these plants on this soil.
Expected Yields and Returns for Corn Due to Nitrogen and Plant Population1
Authors: Colyer Dale , Kroth Earl M. 
Published: July 2010

AbstractExpected corn (Zea mays L.) yields, net returns, and variances have been calculated from predicted yield data based on regression analysis of nitrogen and population experiments for 7‐ and 8‐year periods in Missouri. Data from non‐irrigated and irrigated experiments are used for comparative purposes. The pattern of expected yields and returns was similar for the two sets of data although maximum yields and returns for the irrigated plots were greater and were obtained at greater input levels for both nitrogen and population. However, variance patterns, which result from different levels of nitrogen use, were quite disimilar. Variance generally increased with larger N inputs for the non‐irrigated experiment but decreased for the irrigated site. Variances tended to reach a maximum (non‐irrigated) or minimum (irrigated) at about the peak of expected yields.
Influence of Post Harvest Residue Management and Fertilization on Crop Yield1
Authors: Conrad B. E. , Holt C. E. 
Published: July 2010

AbstractYields of forage sorghum (Sorghum bicolor (L.) Moench.) were significantly different when grown under two management systems over a 5‐year period. Allowing regrowth to occur until October 15 resulted in first harvest forage sorghum yields in the succeeding season of approximately 79% of standard tillage. Fertilization response was also influenced by regrowth management. Similarly, in a 2‐year grain sorghumguar rotation, guar (Cyamopsis tetragonoloba (L.) Taub.) yields were reduced following a grain sorghum (Sorghum bicolor (L.) Moench.) stubble regrowth system.
Early Growth of Crownvetch under Reduced Light1
Authors: Langille Alan R. , McKee Guy W. 
Published: July 2010

AbstractIn 1963 and 1964, three varieties of crownvetch were subjected to six levels of shading (31% to 100% full daylight) to evaluate responses of this species to reduced light under field conditions. In neither year did shading significantly alter percentage total available carbohydrates in the roots but root weight was greatly reduced. Absolute carbohydrate levels varied significantly between years and varietal differences were significant. Under shaded conditions root growth was affected to a greater extent than top growth. Percentage crude protein in the forage increased as shading increased.
Serological Distribution of Soybean Root Nodule Bacteria in Soils of Southeastern USA1
Authors: Caldwell B. E. , Hartwig E. E. 
Published: July 2010

AbstractFour soybean genotypes were sampled in eight different plantings during the years 1967 and 1968, to determine the variability in Rhizobium japonicum population. Considerable variability occurred among locations in the serological distribution of nodules in the cultivar ‘Lee.’ The serogronp patterns for nodules formed on soybean genotypes D49‐772 and D55‐4102 were different from those formed upon Lee at several of the locations. Results indicate that an effective relationship can be established between a soybean genotype and a wide range in serogroups of R. japonicum.
Root Response of Merion Kentucky Bluegrass Sods to Various Nitrogen Applications near the Time of Transplanting1
Authors: Dunn J. H. , Engel R. E. 
Published: July 2010

AbstractRegrowth of the root system of transplanted sod has become a major concern in turf production. Since nitrogen is used on most turf sod installations, the amount of nitrogen applied and the time of its application may have important effects on the regeneration of roots from sods.Re‐rooting of Merion Kentucky bluegrass sods given surface applications of N before transplanting, at the time of transplanting, and after transplanting to root observation containers in spring and summer was compared with that of sods given no N. Measurements included dry weights of roots grown from sods, rate of new root appearance, and color ratings.Applications of 98 and 293 kg/ha of N to the surface of Merion Kentucky bluegrass sod before transplanting and at the time of transplanting increased re‐rooting compared with sods given no N.Proper timing is important for the best use of N in root regrowth from sods. Applications of N dose to the time of transplanting were more beneficial to rerooting than applications at longer intervals before or after transplanting.N decreased the carbohydrate content of topgrowth of sods by 20 to 25% at 23 days after transplanting in the summer test compared with sods given no N. Increased root regrowth was associated with decreased carbohydrates of topgrowth of sods given N at 4 days before transplanting and at the time of transplanting, but this did not occur when N was applied 9 days after transplanting.
Field Evaluation of Alfalfa Cultivars for Resistance to the Alfalfa Weevil in Mississippi — a Preliminary Study1
Authors: Pitre Henry N. , Watson Vance H. , Ward Coleman Y. 
Published: July 2010

AbstractSignificant correlation coefficients (P=.05) of −0.42 and −0.59 were obtained for first harvest dry matter yields of alfalfa and alfalfa weevil populations. ‘Vernal,’ ‘Rhizoma,’ and ‘MSHP7’ varieties were consistently lower in alfalfa weevil infestations than the other varieties evaluated. Population levels decreased rapidly in May and were not a serious problem after the first harvest.
Plant Varieties as Indicator of Aluminum Toxicity in the A2 Horizon of a Norfolk Soil1
Authors: Long F. Leslie , Foy Charles D. 
Published: July 2010

AbstractTwo varieties of barley (Hordeum vulgare, L., emend, Lam.) and two varieties of snapbeans (Phaseolus vulgaris, L.), known to differ widely in their tolerance to aluminum, were used as biological indicators of aluminum toxicity in the A2 horizon of an acid Norfolk soil (pH 5.2). Both top and root growth of the indicator varieties supported the conclusion that aluminum toxicity is an important growth‐limiting factor in the Norfolk soil studied. Leaf rolling observed in aluminum‐sensitive ‘Kearney’ barley (but not in aluminum‐tolerant ‘Dayton’) grown on the unlimed soil, was attributed to aluminum induced calcium deficiency.
A Versatile, Precision Plot Planter1
Authors: Brigham Raymond D. 
Published: July 2010

AbstractA tool‐bar‐mounted four‐row plot planter, capable of precision‐planting many field crop and vegetable seeds, was designed and assembled. Four unit planters equipped with chisel‐pointed openers, covering knives, and soil press wheels were fitted with inclined plate boxes, modified with hand cranks and spring clutches for rapid emptying of remnant seed. Two gauge wheels, seats, footrests, racks for seed boxes, and a 3‐point tool carrier were also attached to the tool bar. The plot planter, operated by two men plus a tractor driver, can be quickly attached to any tractor of adequate size that is equipped with a 3‐point hitch, and can be used to plant on top of a bed, in a furrow, or on a flat seedbed.
Runoff Farming in the Desert IV. Survival and Yields of Perennial Range Plants1
Authors: Tadmor N. H. , Evenari M. , Shanan L. 
Published: July 2010

AbstractSurvival, performance and yields of 80 ecotypes of 30 perennial range plant species grown with water spreading in a 100‐mm winter‐rainfall desert, were recorded over a 9‐year period. Phalaris tuberosa, Oryzopsis miliacea, and Medicago sativa were outstanding in all respects, surviving a 34‐month drought period and recovering to yield 25 to 35 ton/ha fresh matter (6 to 11 ton/ha dry). Festuca arundinacea, Hyparrhenia hirta, Cynodon dactylon, Dactylis glomerata, Hordeum bulbosum, and Panicum antidotale also produced substantial yields.
Effect of Sulphur in Preventing the Occurrence of Chlorosis in Peas1
Authors: Singh H. G. 
Published: July 2010

AbstractResults of a field experiment, comprising a control, two micronutrient preparations, two phosphate fertilizers, singly and in combination, with and without sulphur, showed that only the application of sulphur was effective in preventing the occurrence of chlorosis. The application of 250 kg/ha sulphur increased the grain yield of peas 100%. The chlorotic leaves contained 40% more Fe, 10% more Al, and 31% more Si but 10, 17, 10, 11, and 25% less N, K, S, Mg, and B, respectively, than green leaves. Differences in grain yield and leaf composition (except for sulphur) were statistically significant. Micronutrient treatments did not affect the yield of the crop but had significant effect on leaf contents of N, Na, Fe, Mn, Mo, and Al. Phosphate fertilizers slightly increased the grain yield but had no effect on leaf composition.
Summer Fallow Soil Water Losses on Intermountain Dryland and Its Effect on Cropping Winter Wheat1
Authors: Massee T. W. , Siddoway F. H. 
Published: July 2010

AbstractIntermountain drylands lose water from the root zone during the summer of fallow even though they receive a monthly average of 3.1 cm of precipitation. Soil water content in the 7.5‐ to 15‐cm seed zone at the end of summer fallow was related to soil water content at the time tillage was initiated in the spring. Fall soil water content was not appreciably affected by variations in summer rainfall. Adequate soil water for winter wheat Triticum aestivum L. em Thell) emergence was best assured by initiating summer fallow tillage when the water content in the 7.5‐ to 15‐cm layer was relatively high, rather than depending on summer rain to rewet this layer.
Design and Use of an Anhydrous NH3 Applicator for Field Research1
Authors: Smiley R. W. , Papendick R. I. 
Published: July 2010

AbstractA compact, tractor‐mounted anhydrous NH3 applicator for field plot studies was designed, constructed, and tested. The metering pump is driven by one of two depth control wheels. The applicator chassis was custom fabricated; commercially available components, including the main tank were used for construction of the NH3 application system. Important features include readily interchangeable tool bars holding the applicator shanks, and a second tank for applying formulations of anhydrous NH3 with other chemicals.
Nitrate Accumulation in Vegetables. II. Table Beets Grown in Upland Soils1
Authors: Peck N. H. , Barker A. V. , MacDonald G. E. , Shallenberger R. S. 
Published: July 2010

abstractNitrate concentrations in table beet (Beta vulgaris L.) plant parts were determined for different sources and times of application of N fertilizers to a Honeoye fine sandy loam and a Lima silt loam to determine effects of N fertilization on the concentration of nitrates in the plant parts used for consumption for food.Nitrate concentrations were determined potentiometrically, using a nitrate‐selective ion electrode, on plant samples taken at time intervals after N fertilization and at harvest stage for processing.Nitrate concentrations in table beet roots, leaf blades, and petioles were increased significantly by applications of N fertilizers. Rate of N application was the most significant factor affecting NO3 accumulation in the plants. Carrier of N was a significant factor only when the N fertilizers were sidedressed shortly before harvest. Sidedressing before harvest with KNO3 and broadcasting before planting with NH4NO3 and urea gave similar concentrations of NO3 in the plants. Beet leaves were significantly higher in NO3 than roots.
Characterization of Corn (Zea mays L.) Canopies from Measurements of Individual Plants1
Authors: Daynard T. B. 
Published: July 2010

abstractBecause of their distichous growth habit, the foliage structure of individual corn (Zea mays L.) plants can be diagrammed by placing them against a flat surface and outlining leaf positions on the surface by means of a marking pencil. A method is described whereby measurements made in such a manner are used by a computer program to predict the canopy characteristics of identical corn plants in various planting arrangements. The program output includes quantitative two‐dimensional descriptions of plants placed in different row‐width planting patterns, plus a measure of the leaf area and leaf angle characteristics of the various vertical layers of such canopies. Typical results with two common hybrids are presented.