bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arsenic Residue Toxicity to Vegetable Crops Grown on Plainfield Sand1
Authors: Jacobs L. W. , Keeney D. R. , Walsh L. M. 
Published: July 2010

AbstractIn a field study, sodium arsenite, which is used widely in Wisconsin as a defoliant for potatoes, was applied to a Plainfield sand at rates ranging from 45 to 720 kg As/ha. The plots were planted to potatoes in 1967; peas, snap beans, and sweet corn in 1968; and to peas in 1969. Yields of potatoes were greater than check at the 45 and 90 kg As/ha rates, but decreased to 79 and 24% of check yield at the high As rates. Snap bean and sweet corn yields also decreased with increasing As, and no growth was obtained on the high As plots. The As content of above‐ground portions of potatoes varied widely, and bore no relationship to As treatment. Evidence of As contamination by windblown As‐treated soil was obtained. Arsenic was below detectable limits in edible portions of peas and sweet corn, but up to 0.5 ppm of As accumulated in potato tubers and up to 84 ppm in potato peelings. Detectable levels of As occurred in snap beans, with up to 1 ppm As accumulating in snap bean seeds and pods from the 180 kg As/ha plots. Yield decreases were related highly to total, 1 N NH4OAc extractable and Bray P‐l extractable As. The data suggest that, with the Plainfield sand, marked yield reductions of peas, snap beans, and sweet corn occur at about 10, 1, and 5 ppm of total,N NH4OAc, or Bray P‐l extractable As, respectively. The finding that yield reductions and As contamination of vegetable crops will occur indicates that use of As as a potato vine defoliant on sandy soils should be discouraged.
Germination of Cultivars of Trifolium subterraneum L.1
Authors: Young James A. , Kay Burgess L. , Evans Raymond A. 
Published: July 2010

AbstractThe germination of seeds of 11 cultivars of subclover (Trifolium subterraneum L.) grown in California was depressed by high temperatures, and depressed by low temperatures, or they remained dormant or non‐sensitive in relation to incubation temperatures of 0.5 to 20 C. Cultivars with a relatively non‐sensitive response to this range of temperatures were least responsive to other manipulations of the germination environment. Cultivars depressed by high or low temperatures were markedly stimulated in germination when incubated at 5, 10, or 15 C with an activated charcoal substrate, or in a CO2‐ enriched atmosphere. Germination of the cultivars ‘Mt. Barker’ and ‘Bacchus Marsh’ at low temperatures was increased when incubation was on inclined plates. These cultivars also responded to the addition of 1.0 × 10‐4 to 1.0 × 10‐2 M KNO3 solutions to the germination substrate. Pellet inoculation of seeds did not stimulate germination except with ‘Dwalganup’ at 0.5 to 10 C.
Tillage Methods for Corn‐Sod Systems in the Southern Piedmont1
Authors: Adams William E. , Pallas James E. , Dawson R. N. 
Published: July 2010

AbstractCorn (Zea mays L.) was grown in Coastal bermudagrass (Cynodon dactylon (L.) Pers.) with treatments representative of conventional, mulch, strip, and no‐tillage systems, both with and without irrigation on Cecil soil. Corn was also grown in tall fescue (Festuca arundinacea L.) with treatments representative of conventional, mulch, and no‐tillage systems, also with and without irrigation. The ability to grow corn in Coastal bermudagrass and fescue sods is primarily related to the degree of competition offered by the perennial grasses, with success or failure of the corn‐sod system depending on soil water availability.In 1961, a year of above‐average rainfall, corn grain yields without irrigation ranged from 4,077 kg/ha in the corn system treated with 4.5 kg/ha of maleic hydrazide to 6,586 kg/ha for the conventional treatment. In 1962, a year of below‐average rainfall, corn yields ranged from 314 to 3,700 kg/ha for the same two treatments.Fescue grass was less competitive than Coastal bermudagrass; therefore, corn yields with fescue grass were generally higher than with Coastal bermudagrass.The lister‐planter treatment as well as the 4.5‐ and 9‐kg/ha maleic hydrazide rates applied to the grasses delayed corn germination and tasseling, reduced the height of the plant, average number of ears per stalk, and ear weight.A corn‐sod system with minimum tillage is feasible in the Southern Piedmont region; however, to be assured at good grain production, irrigation is necessary.
Palatability, Chemical Composition, and Animal Gains from Selections of Weeping Lovegrass, Eragrostis curvula (Schrad.) Nees.1
Authors: Voigt P. W. , Kneebone W. R. , McIlvain E. H. , Shoop M. C. , Webster J. E. 
Published: July 2010

AbstractSignificant differences in palatability were detected with Hereford steers among curvula‐type selections within Eragrostis curvula (Schrad.) Nees.Two of the most palatable selections were lower in lignin, higher in cellulose, and lower in lignin‐cellulose ratio than two unpalatable selections. These two palatable selections were also taller, later in heading, and slightly wider in leaf than two unpalatable selections.Over a 3‐year period, Hereford steers grazing the most palatable selection gained 13% more per head than those grazing one of the least palatable selections, and 12% more per head than those grazing common, also of low palatability.Evaluation of palatability within the curvula‐type of E. curvula resulted in selection of a strain capable of producing higher steer gains than common.
A Temperature Model for Predicting Initial Cotton Emergence1
Authors: Wanjura D. F. , Buxton D. R. , Stapleton H. N. 
Published: July 2010

AbstractAn empirical temperature model for predicting initial emergence time of cotton planted at 5.1 cm is described. The model is verified by comparing predicted values with data collected in field studies. The applicability of the model is confined to field situations in which soil temperature is the primary parameter exerting a limiting influence on cotton seedling emergence.
Productivity of Crimson and Arrowleaf Clovers Grown in a Coastal Bermudagrass Sod1
Authors: Knight W. E. 
Published: July 2010

AbstractA split‐plot field experiment compared annual seeding and self‐reseeding of crimson and arrowleaf clovers in a Coastal bermudagrass sod. Clover species did not differ significantly for seedling counts. Earlier growth was produced by self‐reseeding stands. However, stands from both methods of seeding were good and growth was relatively uniform in all plots. Differences in total production were not significant for method of seeding. Crimson clover averaged 33% more forage than arrowleaf. The lower yields of arrowleaf were caused by poor recovery and regrowth under drought stress.Grass following clover produced 18% more forage than grass receiving 224 kg/ha N without clover. Total grass yields following crimson and arrowleaf clovers were not significantly different. However, the first grass harvest following arrowleaf was always reduced. This was caused by greater competition from arrowleaf clover than from the earlier maturing crimson clovers.Total forage production was 47% higher from the sequence of clover‐Coastal bermudagrass than from grass — 224 kg/ha N — no clover. Highest total forage was produced by crimson clover‐bermudagrass. Crimson clover contributed 22% to total yield compared to 17% for arrowleaf. This study suggests the utilization of winter annual clovers to partially supply the nitrogen requirement of summer growing grasses. In addition to a reduction in the mineral nitrate requirement, other benefits would be an extended grazing season, increased total forage production, increased forage quality, and better utilization of land resources.
Effects of Row Spacing on Evapotranspiration and Yields of Corn in a Semiarid Environment1
Authors: Fairbourn Merle L. , Kemper W. D. , Gardner H. R. 
Published: July 2010

AbstractA study was made in 1967 and 1968 on a Nunn clay loam soil to determine the effects of row spacing on evapotranspiration (ET) and yields of corn (Zea mays L.) in a semiarid environment. Double rows 0.3 m apart flanked on each side by spaces 1.8 m wide as used in the microwatershed system were compared with single rows in spacings of 0.9, 1.2, and 1.8 m. ET and yields of the double rows and the single rows of 0.9 and 1.2 m spacings were very similar. These results indicate an important degree of freedom is allowed in planning management systems such as microwatersheds to increase water use efficiency.
Influence of “Pop‐up” Fertilizers on Soybean Stands and Yield1
Authors: Clapp J. G. , Small H. G. 
Published: July 2010

AbstractBoth liquid and granular fertilizers containing nitrogen, phosphorus, and potassium were applied directly in the seed zone of soybeans (Glycine max (L.) Merrill) at planting. An application of 35.5 liters/ha (3.8 gallons/acre) of a liquid 5.0‐8.8‐4.2 (N‐P‐K) “popup” fertilizer reduced stands by 57.8% and yields by 20.3%. Plant stands were reduced when only 11.2 kg/ha (10 lb/acre) of a granular 10‐15‐5 (N‐P‐K) “popup” fertilizer was applied in the seed zone at planting.
Variation in Taproot Elongation Rate as Influenced by Composition of the Soil Air1
Authors: Huck M. G. 
Published: July 2010

AbstractElongation rates of cotton and soybean taproots were measured while the O2 content of a gas stream passing through the soil surrounding the roots was varied. Elongation rates were comparable to controls at all O2 concentrations above 10%. Elongation ceased completely within 2 to 3 min after all O2 was purged from the system with 100% N2 gas, and returned to normal shortly after 21% O2 was returned to the system, provided the period of anaerobiosis had not exceeded 30 min. Longer periods of complete anaerobiosis resulted in killing of a certain percentage of root tips until approximately 100% of the primary taproots were killed at 3 hr without O2 for cotton and 5 hr for soybeans. Oxygen levels from 2 to 5% resulted in an initial reduction in rate of taproot extension, followed by a gradual return to elongation rates comparable with controls. Although 3 to 5 hr of complete anaerobiosis evidently killed the terminal meristematic region of the taproots, new lateral growth developed from the cortex within a day or two after cessation of growth of the terminal meristems. Distribution of roots through a volume of soil may thus be influenced by oxygen availability and its distribution through time and space.
Water Use and Soil Water Depletion by Dryland Winter Wheat as Affected by Nitrogen Fertilization1
Authors: Brown Paul L. 
Published: July 2010

AbstractEvapotranspiration, daily water use, and soil water depletion by Feekes scale (7) growth stages of N‐fertilized winter wheat (Triticum aestivum, L. ’Winalta’) were measured under dryland field conditions. Fall‐applied N (NH4NO3) rates were 0, 67, and 268 kg/ha (0, 60, 240 lb/a). Soil water measurements were made at weekly intervals with a neutron moisture meter. Soil NO3−N to 183 cm (6 ft) in early spring was 21 kg/ha 19 lb/a).ET for the spring‐summer growth period was 22.1, 27.2, and 31.5 em (8.7, 10.7, and 12.4 in.) for the respective N treatments. Daily ET reached maximum values at the headed‐to‐flower stage. Soil water extraction was largely limited to the upper 91 cm (3 ft) with no N. With N, the wheat extracted water to 183 cm. Stored soil water supplied 6.1, 11.2, and 15.5 cm (2.4, 4.4, and 6.1 in.) of water to the wheat grown on the three N treatments. This was 30, 55, and 76% of the plant available water to 183 cm. At maturity, there was 18.0. 13.2, and 9.6 cm (7.1, 5.2, and 3.8 in.) of plant available water remaining in the soil to a depth of 183 cm.Grain yields were 1,610, 3,090, and 3,630 kg/ha (24, 46, and 54 bu/a). In addition to increasing ET, N increased water use efficiency by an average of 56%.
Effects of Temperature and Flooding on Rice Growing in Saline and Alkaline Soil1
Authors: Place G. A. , Siddique M. A. , Wells B. R. 
Published: July 2010

Abstract‘Bluebelle’ cultivar of Oryza sativa L. was grown in a growth chamber at 4 and 16, 10 and 21, 16 and 27, and 21 and 33C night (10 hr) and day (14 hr) temperatures, respectively. Flood water was applied 12 (early) or 24 (late) days after seedling emergence at 6‐ and 12‐cm depths to seedlings growing in saline, alkaline, and normal Crowley silt loam soil. Plant tops were harvested 53 days after seedling emergence and analyzed for dry matter production and composition of P, K, Mg, Na, Fe, Mn, and Zn. Water samples were collected at the soil‐water interface 1, 2, 5, 7, 8, 9, 10, 11, 14, and 15 days after seedling emergence and analyzed for pH, electrical conductivity, CO3‐, HCO3‐, and C1‐.When temperature was increased, the order of dry matter production by plants growing in the various soils was normal > saline > alkaline. Applying flood water 12 days after seedling emergence caused plants growing in saline and normal soils to produce more dry matter, whereas those growing in alkaline soil produced more dry matter when flooded 24 days after seedling emergence. Varying flood depth did not affect growth.Plants growing on saline and alkaline soils at 21 and 27C were chlorotic and P/Zn was less than 1.0. When temperature was increased to 31C chlorosis disappeared and P/Zn was greater than 1.0; however, the data did not explain the effects of flood time on growth.Bicarbonate level of water above the alkaline soil was higher when flooding was delayed. This suggested young seedlings were more sensitive to HCO3‐ than were older seedlings, since growth was greater with delayed flooding.Flooding saline soil early produced lower EC and Cl‐ values in the water than did late flooding. Thus, plants grew more when flooded early because salinity was lower.
Effect of Cultivation on the Nitrogen and Organic Carbon Contents of a Kansas Argiustoll (Chernozem)1
Authors: Hobbs J. A. , Thompson C. A. 
Published: July 2010

AbstractAs a continuation of a Kansas dryland‐soil study, started in 1916, samples from 44 plots and 2 uncultivated areas at the Ft. Hays Experiment Station were analyzed to determine the effects of a single cropping system (fallowwheat‐sorghum) from 1956(58) to 1966 on soil organic‐matter content.Surface soils containing more than 0.100% nitrogen in l958 generally lost nitrogen between 1958 and 1966; those containing less than 0.100% generally gained nitrogen. A regression equation developed from the relationship between 1958 nitrogen content and 1958‐to‐1966 loss (or gain) predicted an equilibrium‐nitrogen content of 0.103%.Nitrogen losses from surface soils followed a curvilinear trend, as in earlier phases of this study. Relation between soil‐nitrogen content and duration of cultivation, developed from a knowledge of nitrogen contents of unbroken sod and of cultivated plots from 1915 through 1966 predicted that, with the fallow‐wheat‐sorghum cropping system and no additional organic matter or commercial fertilizer, the soil‐nitrogen content should stabilize eventually at 0.103%.Subsoils (18 to 51 cm) lost nitrogen between 1958 and 1966, which contrasted with results from earlier samplings.
“Runoff Farming” in the Desert. V. Persistence and Yields of Annual Range Species1
Authors: Tadmor N. H. , Shanan L. , Evenari M. 
Published: July 2010

AbstractA wide variety of medics and other annual range plants were grown over a 9‐year period under waterspreading conditions in an 80 to 100‐mm winter rainfall desert. The only irrigation came from natural surface‐runoff during winter storms. Ecotypes of Medicago polymorpha, M. orbicularis, M. rotata, M. scutellata, M. truncatula, M. turbinata, and Trigonella arabica reseeded themselves each year and yielded up to 20 to 30 ton/ha fresh (4 to 6 ton/ha dry) matter. Several cultivars of forage crops and other large‐seeded crop plants, i.e. barley, oats, vetches, gave high yields but failed to perpetuate. It took legumes 3 to 4 years to become naturally inoculated. None of the clovers were established successfully under these conditions.
Corn Yields with Fall, Spring, and Sidedress Nitrogen1
Authors: Welch L. F. , Mulvaney D. L. , Oldham M. G. , Boone L. V. , Pendleton J. W. 
Published: July 2010

AbstractStudies in central and northern Illinois at 4 locations and 12 location‐years were conducted with 5 rates of N applied in the fall and as spring‐preplant. Sidedress N was also included at 1 of the 4 locations for 4 years. Relative efficiency of the times of application was calculated by dividing the corn (Zea mays L.) yield increase from a given rate of N added at one time by the yield increase from the same rate of N applied at another time.At the Carthage and Hartsburg locations the 3‐year average relative efficiencies of fall‐ versus spring‐applied N are about 0.8 and 0.9 (fall was 80 and 90% as effective as spring) at N rates of 67 and 134 kg/ha, respectively. Fall and spring N were about equally effective at 201 and 268 kg/ha of N. There was generally little yield response to N rates greater than 201 kg/ha at Carthage and Hartsburg. Fall and spring N gave similar corn yields for all rates of N at Urbana.For the 4‐year average at DeKalb, sidedress N was the most effective, spring N was intermediate, and fall‐applied N was the least effective. The difference between spring and sidedress N was less than that between fall and spring N.There was considerable year‐to‐year variation in relative efficiency. The importance of the time at which conditions suitable for N loss occur is discussed.
Nitrogen Fertilization of Semiarid Grasslands: Plant Growth and Soil Mineral N Levels1
Authors: Power J. F. , Alessi J. 
Published: July 2010

AbstractTo evaluate the fate of mineral N in a grassland ecosystem, fertilizer N was applied to native grassland in North Dakota at rates up to 540 kg N/ha either (a) all in 1 year, (b) one‐third in each of 3 years, or (c) one‐sixth each of 6 years. Cumulative production of grass tops for the 6 years increased with increased amounts of total N applied, but was not affected by timing of fertilizer application. With continued annual fertilization, responses were measureda at progressively lower rates. At 270‐kg N or more, residual effects were still significant 6 years later. Dry weights of three oats crops grown on these soils in the growth chamber indicated that greater N availability in fertilized soils contributed appreciably to these residual effects. Soil NH4+‐ and NO3‐‐N levels for many treatments exhibiting residual effects were no higher than for unfertilized plots, indicating residual N was present in other than mineral forms. Fertilizer N is probably immobilized by all components of the soil‐grass ecosystem (especially grass roots) and the mineralization of this immobilized N may contribute to residual effects. Fertilizer N applied in excess of the immobilizing capacity of the ecosystem remains in mineral form until required by the grass. Consequently, the presence of a mineral N pool indicates that N has been eliminated as a growthlimiting factor and maximum production from the available water is being achieved.
Root Development and Rooting Patterns of Soybean (Glycine max (L.) Merrill) Evaluated Under Field Conditions1
Authors: Mitchell R. L. , Russell W. J. 
Published: July 2010

AbstractThe soybean (Glycine max L.) root system, by 21 days after planting, consisted primarily of secondary lateral roots that had developed from an enlarged upper 10‐ to 15‐cm segment of the “taproot.” Four longitudinal rows of lateral roots spaced at 90 degree intervals around the taproot developed acropetally. These laterals grew horizontally for 40 to 50 days and, after reaching 35 to 40 cm in length, turned downward, providing extensive deep penetration of the soil profile.Root growth and development occurred in three phases, each phase corresponding to specific vegetative or reproductive stages. The completion of each phase of development represented further penetration of the soil profile and proliferation by the root system.Root dry weight was concentrated in the upper portion of the soil profile, 90% or more in the upper 7.5 cm early in the season and in the upper 15 cm during the remainder of the season.Differences were observed among the eight varieties sampled for rate of root developmnt, total root dryweight accumulated, and type of rooting pattern.
A Self‐Watering System for Growing Plants in Potted Soils1
Authors: Dolar S. G. , Keeney D. R. 
Published: July 2010

AbstractA wick culture technique for growing plants in potted soils was developed. In the method described, about 50 oat (Avena sativa L.) seeds are sown to a pot and are grown under plant‐growth room conditions for about 4 weeks. Water for the plants is supplied entirely by a fiberglass wick extending from the center of the pot into a glass cylinder. The technique is especially adaptable to micronutrient element studies. It has several advantages over the ordinary pot culture techniques for growing plants. The construction materials are available and inexpensive.
Moisture Requirements for Seed Germination of Peanuts1
Authors: Mixon Aubrey C. 
Published: July 2010

AbstractPeanut seed (Arachis hypogaea L. var. ‘Early Runner’) were removed from moist germination pads, covered with germination blotters in a 25 C germinator at 30‐ to 45‐min intervals and placed in sealed petri plates to allow seed germination (radicle emergence). Seed moisture at time of placing in sealed container revealed that average seed moisture of about 35% was necessary for any seed to germinate. Radicle emergence of all seed in a sample was obtained at about 55 to 60% average seed moisture.
Competition between Grass and Legume Species on Dryland1
Authors: Dubbs Arthur L. 
Published: July 2010

AbstractTwo legumes and four grasses were grown in various combinations on dryland to determine the degree of competition one species exerted upon another. Species competition was measured by stand percentage, forage yields, plant height, and percent crude protein. Russian wildrye (Elymus junceus Fisch.) was the most competitive species and sainfoin (Onobrychis viciaefolia Scop.) the least under conditions experienced at this location during the trial period. Sainfoin was the only species showing a significant loss of stand during the 5‐year period. The stand loss resulted from a combination of winterkilling and species competition. Grasses yielded more when competing with legumes than when competing with each other. Competition between grasses was nearly equal and no combination excelled another. Russian wildrye and alfalfa (Medicago sativa L.) were the most competitive species with sainfoin. Alfalfa plants received more competition from other alfalfa plants than from plants of other species. In general, all species were quite competitive to themselves in pure stands. Percentage crude protein of crested wheatgrass (Agropyron desertorum (Fisch.) Schutl.) increased when it was grown with alfalfa. The protein content of sainfoin was not affected by competition from any of the species. Alfalfa and Russian wildrye decreased in crude protein content when competing with smooth bromegrass (Bromus inermis Leyss.).