bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cotton Yield and Fiber Quality Response to Green Manures and Nitrogen
Authors: Bauer P. J. , Camberato J. J. , Roach S. H. 
Published: July 2010

AbstractThe quantity and availability of N from green manures will considerably affect the N management of a succeeding cotton (Gossypium hirsutum L.) crop. This study was conducted to determine the N supplying capacity of crimson clover (Trifolium incarnatum L.), Austrian winter pea [Pisum sativum subsp. arvense (L.) Poir.], and rye (Secale cereale L.) to cotton and their influence on cotton yield and fiber properties. Green manure treatments (and a fallow check) with fertilizer N levels of 0, 56, 112, and 168 kg ha−1 were compared for 3 yr on a Norfolk loamy sand (fine‐loamy, siliceous, thermic Typic Kandiudult). Soil moisture at planting was similar among the four green manuretr eatments. At the 0 N level, the legumes generally had higher soil NO3‐N than rye or fallow. Cotton grown following clover and pea with 0 kg ha−1 added N had petiole NO3‐N levels similar to those of rye and fallow with 56 kg N ha−1. Fertilizer N had no influence on cotton yield in the pea winter cover treatment. A quadratic regression equation best described the lint yield response following clover. For both rye and fallow treatments, yield plateaued at 56 kg N ha−1. Green manures had little influence on fiber properties. The results indicate that legumes supply adequate but not excessive N for modern cotton production and that incorporation of rye into the production system does not affect N fertilization requirements.
High pH Treatments and the Alleviation of Soil Hydrophobicity on Golf Greens
Authors: Karnok Keith A. , Rowland Everett J. , Tan Kim H. 
Published: July 2010

AbstractHydrophobic soil associated with localized dry spots (LDS) on creeping bentgrass (Agrostis palustris Huds.) putting greens has been shown to be caused by a humic and/or fulvic acid coating of the sand particles. Under laboratory conditions, humic acid begins to solubilize at pH 7.0 and is completely soluble at pH 9.5 or greater. The purpose of this study was to determine the potential of high pH treatments for alleviating soil hydrophobicity of a creeping bentgrass golf green. Three separate studies were conducted on the University of Georgia Experimental Golf Green, Athens, GA, during the spring and summer of 1990 and spring of 1991. The creeping bentgrass green, constructed with an 85% sand and 15% peat root zone mixture, had a well documented history of LDS caused by hydrophobic soil. Soil hydrophobicity was determined by the molarity of an aqueous ethanol droplet (MED) technique. Results showed that an application of 0.1 M NaOH sufficient to saturate the upper 50 mm of soil, followed by a water flush of one pore volume, significantly reduced soil hydrophobicity if repeated three or more times. In one study, soil hydrophobicity was completely eliminated after nine consecutive daily treatments of 0.1 M NaOH, each of which was followed by a water flush. A concurrent decrease in soil humic matter content suggested that its dissolution and removal was responsible for the increased wettability of the soil profile. Bentgrass treated with NaOH showed varying degrees of phytotoxicity. The severity of injury depended on the number of consecutive applications and air temperature. Little or no discoloration was noted when air temperatures was ≤24 °C; however, severe wilt and desiccation occurred when treatments were applied when air temperature was ≥ °C. High pH treatments may be an effective means to reduce soil hydrophobicity on sand‐based golf putting greens.
Alfalfa Growth Following Release from Drought Stress
Authors: Hall Marvin H. 
Published: July 2010

AbstractCompensatory growth (increased growth relative to normal) of alfalfa (Medicago sativa L.) when released from periods of drought stress has been observed or suggested. The objective of this research was to determine whether such compensatory growth does occur. Alfalfa was subjected to drought stress (plant water potential < ‐ 1.5 MPa) for 2 and 4 wk in a greenhouse study and 2, 4, and 6 wk in a field (Palouse silt loam soil, fine‐silty, mixed, mesic Pachic Ultic Haploxerolls) study near Moscow ID. Following harvest and removal of the drought stress, plant growth measurements were made after 30 d of growth in the greenhouse and biweekly during 5 wk of growth in the field. At the conclusion of the growth periods in both greenhouse and field studies, average stem length and dry matter yield of previously drought‐stressed plants were 88 and 91%, respectively, compared with previously unstressed plants. Stem growth rates of field grown plants were less for the previously stressed plants only during the first 2 wk after release of stress. Stress treatments did not affect stems per plant (greenhouse) or stems per square meter (field). Leaf area per stem, however, for the previously drought‐stressed plants was 122 and 108% compared with previously unstressed plants in the greenhouse and field, respectively. Leaf area was greater in the growth period following drought stress, but stem length and dry matter yield were reduced. Previous observations of apparent compensatory alfalfa growth after a drought may be attributed to increased leaf area.
Productivity of Four Annual Legumes as Green Manure in Dryland Cropping Systems
Authors: Biederbeck V. O. , Bouman O. T. , Looman J. , Slinkard A. E. , Bailey L. D. , Rice W. A. , Janzen H. H. 
Published: July 2010

AbstractIntegration of green manuring as fallow replacement in dryland cereal production requires selection of well‐adapted legumes. The objectives of this study were to (i) analyze vegetative growth of annual legumes and (ii) assess the relative merits of each legume as shortterm green manure crop. Inoculated black lentil (Lens culinaris Medikus), Tangier flatpea (Lathyrus tingitanus L.), chickling vetch (Lathyrus sativus L.), and feedpea (Pisum sativum L.) were tested on an Orthic Brown Chernozem soil (Aridic Haploborolls) at Swift Current, SK, Canada, from 1984 to 1990. Legume species and years differed significantly in dry matter (DM) production of shoots, roots, and nodules; DM partitioning; growth habit; relative growth rate; and weediness. Total legume DM ranged from 601 to 3961 kg ha−1, with 6‐ yr means of 1669 kg ha−1 for black lentil, 1486 for Tangier flatpea, 2230 for chickling vetch, and 3008 for feedpea. Nodulation was most abundant with chickling vetch and least with Tangier flatpea; nodule DM ranged from 2 to 329 kg ha−1. Coefficients of determination between nodule and legume DM were r2 = 0.93*** for chickling vetch and r2 = 0.78*** for feedpea, indicating their ability to benefit from symbiosis with Rhizobium. Nodulation was greatly influenced by soil mineral N and soil water. Average DM allocation to roots as a percentage of total legume biomass averaged =7% for chickling vetch and feedpea and 12% for black lentil and Tangier flatpea. Feedpea canopy height was double to triple that of black lentil. The degree of decumbency (stem length/canopy height) was 1.09 for black lentil, 1.19 for chickling vetch, 1.21 for feedpea, and 1.29 for Tangier flatpea. Growth rate analysis identified chickling vetch as an early‐developing legume. Feedpea and chickling vetch were definitely more suited to green manuring in semiarid climates than black lentil and Tangier flatpea. Feedpea has good growth habits and greatest DM production. Chickling
Long‐Term Effect of Five Tillage Systems on Corn Response and Soil Structure
Authors: Vyn T. J. , Raimbult B. A. 
Published: July 2010

AbstractTillage systems need to be compared over an extended period of time to determine their transitional and long‐term impacts on crop growth and soil properties. A 15‐yr experiment established in 1976 compared reduced tillage systems with conventional fall moldboard plowing for production of continuous corn (Zea mays L.) on a Maryhill silt loam soil (Typic Hapludalf). Corn plant growth and yield and soil properties were compared for five tillage systems: fall plow (fall mold‐board plow + spring secondary tillage), fall chisel plow (fall chisel plow + spring secondary), spring plow, spring plow/secondary (spring plow + secondary), and no‐till. No‐till consistently resulted in slower plant growth than most or all of the other tillage systems. The fall plow and spring plow/secondary treatments resulted in grain yields averaging 5% more than fall chisel plow, 9% more than spring plow, and 16% more than no‐till yields. From 1976 to 1983, no‐till yields tended to increase relative to fall plow; from 1988 to 1990, however, no‐till yields were much less than fall plow. No‐till resulted in the lowest proportion of aggregates <5 mm in diameter, highest bulk density, and greatest penetrometer resistance. Penetrometer resistance of the spring plow plots increased at a slower rate with depth than the fall chisel plow system. Among soil properties measured, the proportion of aggregates <5 mm in diameter was most often significantly correlated with yield.
Legume Cover Crop Options for Grain Rotations in Wisconsin
Authors: Stute James K. , Posner Joshua L. 
Published: July 2010

AbstractUse of forage legumes as cover crops in the year prior to corn (Zea mays L.) is one way to reduce the amount of N fertilizer used in corn production. This study evaluated several forage legumes for dry matter (DM) production during the seeding year when established in grain rotations. Field studies were conducted near Arlington and Marshfield, WI, in 1989 and 1990. Treatments consisted of nine forage legumes: medium and mammoth red clover (Trifolium pratense L.), dormant and nondormant alfalfa (Medicago sativa L.), alsike clover (T. hybridum L.), ladino clover (T. repens L.), hairy vetch (Vicia villosa Roth), and two cultivars of yellow sweetclover [Melilotus officinalis (L.) Lam.]. Five establishment treatments tested were: seeded in the spring, companion‐seeded with oat (Avena sativa L.), interseeded into corn at last cultivation, and seeded following harvest of either canning pea (Pisum sativum L.), or oat for grain. In general, legume DM yields were highest in establishment periods which offered the longest growing season with the least amount of competition from the primary crop. Hairy vetch, the only annual legume used in the study, produced the highest yields in each of the five establishment periods, as high as 9.76 Mg ha−1 when spring seeded. The climbiing nature of this legume, however, makes it an unwise choice for companion seeding with small grains, a situation where the true clover species are best adapted. Dry soil conditions following pea or oat harvest often limited legume germination, seedling growth, and ultimately DM yield. Interseeding of legume cover crops into corn at last cultivation resulted in low seeding‐year DM yields. From the results of this study, we conclude that several legume‐establishment period combinations could be used successfully to produce N‐containing biomass.
Soil Fumigation within Monoculture and Rotations: Response of Corn and Mycorrhizae
Authors: Jawson Michael D. , Franzluebbers Alan J. , Galusha Deborah K. , Aiken Robert M. 
Published: July 2010

AbstractThe causative factors for corn (Zea mays L.) response to methyl bromide (CH3Br) fumigation, in the absence of known specific pathogens, are unknown. This study was conducted to determine if deleterious nonspecific rhizosphere microorganisms are the causative agents. Soil fumigation was postulated to increase yield of continuous corn but to have less effect on the yield of corn grown in rotation, because more deleterious rhizosphere microorganisms were suspected in monoculture than in rotation. The effects of fumigation and crop rotation on corn grain yield, plant height and P content, available soil N and P, mycorrhizal infection, and soil microbial biomass were investigated at two sites near Mead, NE, on a Sharpsburg silty clay loam soil (fine, montmorillonitic, mesic Typic Argiudoll). Methyl bromide treatments were applied prior to planting for 4 yr at one site and 2 yr at the other site. The sites differed in fertilization, pest management, and crop sequences, but both contained continuous corn. Fumigation resulted in an increase in grain yield under monoculture only once in six site years. Unexpectedly, however, fumigation resulted in a decrease in grain yield under rotation in 7 of 12 observations. Plants in fumigated soil were P‐deficient early in the growing season despite similar soil test P concentrations in control and fumigated plots. Fumigation reduced mycorrhizal infection and soil microbial biomass. Mycorrhizal infection of corn shortly after germination appears to be important to initial corn growth in this soil. Fumigating soil revealed a considerable biological influence on corn growth and yield by reducing both deleterious and beneficial microorganisms.
Soil Drainage Influence on Biomass and Nitrogen Accumulation by Ryegrass
Authors: Stout William L. , Schnabel Ronald R. 
Published: July 2010

AbstractGrasslands are the basis for a stable agriculture in the Northeast USA. However, knowledge of interactive effects of soil drainage and N fertilization on grassland production in this region remains scant. Our objective was to quantify the effect of soil drainage on grassland biomass production and N accumulation. The study was conducted for 2 yr on a floodplain site in central Pennsylvania on two soils selected for extreme drainage conditions. Perennial ryegrass (Lolium perenne L. cv. Bastion) was treated with a split application (50% in mid‐April, 50% in mid‐July) of 0, 84, 168 and 252 kg N ha−1 of 15N depleted NH4NO3. Biweekly biomass samples were taken starting midMay of each year and continuing until the grass headed and all herbage was removed from the plots. Plots were re‐fertilized and monthly biomass sampling commenced at the end of August and continued until the end of October 31. Fertilizer nitrogen recovery was greatest in the first harvest after fertilization, irrespective of soil type or season. Peak fertilizer N recovery for spring growth was 50% on the well‐drained soil and 32% on the poorly drained soil. In the summerfall growth period, peak fertilizer N recovery was 26% on the well‐drained and 18% on the poorly drained soil. Biomass on the poorly drained soil was 26% less in the spring and 8% less in the summerfall periods compared with that of the well‐drained soil. Overall, poor soil drainage conditions resulted in a 39% reduction in fertilizer N recovery and a 21% reduction in yield of perennial ryegrass.
Soil Sampling Procedures for Monitoring Potassium Distribution in Grazed Pastures
Authors: Mathews Bruce W. , Sollenberger Lynn E. , Nkedi‐Kizza Peter , Gaston Lewis A. , Hornsby H. David 
Published: July 2010

AbstractNutrient redistribution in grazed pastures occurs primarily via deposition of excreta by animals. Because this redistribution is generally not uniform, a composite sample of randomly collected soil cores may not reflect the nutrient status of much of the pasture. To address this limitation, zonal soil sampling, with zones determined by distance from shade, water, and supplemental feeders (lounging areas), has been proposed as an alternative sampling strategy. This experiment was conducted to evaluate the potential of zonal soil sampling for monitoring extractable K distribution in grazed pastures. Utility of the zonal approach was evaluated by comparing it with a more rigorous, but less practical transect sampling procedure. Rotationally and continuously stocked bermudagrass [Cynodon dactylon (L.) Pers. ‘Callie’] pastures were used in the study. Ranges of extractable K within a pasture were as great as 13‐fold (14‐181 mg kg−1) after 2 yr of grazing. Extractable K concentration was greatest in the one‐third of the pastures closest to lounging areas regardless of grazing method. Data from zonal soil sampling described this distribution of soil K. Kriged contour maps constructed using data from transect soil sampling supported the conclusions made using zonal sampling. We conclude that zonal soil sampling is a useful and practical tool for describing K redistribution in pastures and for improving the utility of soil test results and fertilizer recommendations for grazed swards.
Maturity and Lint Yield of Nitrogen‐ and Phosphorus‐Deficient Pima Cotton
Authors: Tewolde H. , Fernandez C. J. , Foss D. C. 
Published: July 2010

AbstractThe Pima cotton (Gossypium barbadense L.) plant is inherently late maturing and unsuitable for production in areas where highly probable late‐season rainfall coincides with boll opening. A field study was conducted between 1990 and 1992 to determine if the maturity of Pima cotton can be enhanced with applied N and P without reducing lint yield. Five preplant‐applied N rates up to 180 kg ha−1 in 1990 and up to 269 kg ha−1 in 1991 and 1992 were tested. Four P rates from 0 to 45 kg ha−1 in a factorial combination with N were tested in 1991 and 1992. Nitrogen did not affect yield, days to first flower, or estimated percent open bolls in 1990. Nitrogen deficiency significantly enhanced maturity in 1991 and 1992. In 1991, >70% of the total bolls opened by 153 days after planting (DAP) where no N was applied, compared with 178 DAP where 202 or 269 kg N ha−1 was applied. In 1992, 68% of the bolls in the 0 kg N ha−1 treatment opened by 142 DAP, compared with <55% for all other treatments. The 0 kg N ha−1 treatment also significantly increased the ratio of reproductive to total plant dry weight earlier during the boll development period; however, the maturity‐enhancing effect of N deficiency occurred at the expense of lint yield. Relative to the 67 kg N ha−1 treatment, zero N reduced lint yield by 277 kg ha−1 (26%) in 1991 and 214 kg ha−1 (18%) in 1992. Phosphorus deficiency reduced lint yield in 1991, but did not affect percent open bolls or reproductive efficiency in 1991 and 1992. Earliness of Pima cotton may, therefore, be managed more effectively by minimizing applied N rates than by manipulating P fertilization.
Profile Water Distribution and Grain Yield as Affected by Cropping System and Tillage
Authors: Norwood Charles 
Published: July 2010

AbstractYields of dryland crops are limited by precipitation in the Great Plains. Winter wheat (Triticum aestivum L.) grown in the wheat‐fallow (WF) system (one crop in 2 yr) occupies the greatest area. The use of grain sorghum [Sorghum bicolor (L.) Moench] in the wheat‐sorghum‐fallow (WSF) system (two crops in 3 yr) is becoming popular. Other cropping systems include sorghum‐fallow (SF) and continuous sorghum (SS). Research was conducted in the central Great Plains at Garden City, KS, from 1987 through 1992 to quantify soil water storage and use and grain yield in the WF, WSF, SS, and SF systems in order to develop more efficient dryland grain production systems. No tillage (NT) and conventional tillage (CT) were compared in the WF and WSF systems. Available soil water at planting and harvest was measured in 0.3‐m increments to a depth of 1.5 m, and grain yield and water use efficiencies were determined. Water moved deeper in the profile under NT. Compared with CT, twice as much water was stored due to NT in the WSF sorghum profile as in the WF and WSF wheat profiles. An average of 62% of the additional water was found below 0.9 m. As much water was stored in the 11‐mo fallow period prior to WSFNT sorghum as was stored in the 15‐ and 19‐mo fallow periods of WF and SF. No tillage resulted in yield increases 17% of the time in WF, 34% of the time for wheat in WSF, and 60% of the time for sorghum in WSF. For sorghum, the yield of SF was similar to that of WSFNT, whereas SS had the lowest grain yield per planted hectare. Efficient storage of precipitation in WSF prior to NT sorghum and increased sorghum yield make the WSFNT system superior to other systems in this study.
Differential Competitive Ability of Winter Wheat Cultivars against Downy Brome
Authors: Blackshaw Robert E. 
Published: July 2010

AbstractDowny brome (Bromus tectorum L.) causes large yield reductions in winter wheat (Triticum aestivum L.) in the western USA and Canada. Current control practices using fallow and preseeding tillage often are ineffective. A study was conducted over 3 yr at Lethbridge, AB, to determine if winter wheat cultivars varying in height and growth habit differ in their competitive ability with downy brome. A factorial set of treatments included downy brome at 0, 10, 50, and 200 plants m−2 grown with winter wheat cultivars Norstar, Redwin, Archer, and Norwin. Downy brome reduced the biomass and seed yield of all cultivars in all years, but the magnitude of the yield reductions differed among cultivars. Downy brome caused 14 to 30% greater yield reductions in the semidwarf cultivars, Archer and Norwin, than in the tall cultivars, Norstar and Redwin. This differential response among cultivars is partly attributable to competition for light. Norstar and Redwin shaded downy brome for much of the growing season, but Archer and Norwin often were shaded by downy brome. Planting a more competitive cultivar of winter wheat results in higher crop yields and less downy brome seed for weed establishment in subsequent crops. Use of competitive winter wheat cultivars should be a component of integrated weed management systems for downy brome.
Growth Dynamics of the Cotton Plant during Water‐Deficit Stress
Authors: Ball Rosalind A. , Oosterhuis Derrick M. , Mauromoustakos Andy 
Published: July 2010

AbstractInformation on the differential growth response of roots and shoots to water‐deficit stress will better describe root growth within the soil for purposes of modeling plant growth and assessment of drought resistant traits. Our aim was to investigate leaf expansion and changes in root elongation for field and growth‐chamber cotton (Gossypium hirsutum L.) during drought. Plants were grown in rhizotron containers and subjected to 6 d of water‐deficit stress followed by 6 d of recovery and compared with a well‐watered control. The stress period commenced when the plants were 55 to 65 d old. Leaf expansion was more sensitive to stress than root elongation, with curtailed growth after 2 d of withholding water compared with 6 d with roots. Stress reduced root elongation and root volume. About 85% of visible roots showed elongation growth under conditions of adequate water, which was reduced by stress to 50%. Small (0.30 mm mean diam.) roots were more abundant and gave the greatest cumulative length, but grew less on a mean length basis than medium roots (0.62 mm mean diam.). The rate of root growth increased during recovery, consisting of regrowth from stalled roots and followed later by initiation of new roots. Medium roots contributed the most to root volume initiated during recovery. Most growth for both root sizes occurred in the lower zone of the soil, where water was more available. Root size and position of roots within the soil profile are important factors to consider when studying root growth response to water‐deficit stress.
Feed Value of Forage Maize Hybrids Varying in Tolerance to Plant Density
Authors: Pinter L. , Alfoldi Z. , Burucs Z. , Paldi E. 
Published: July 2010

AbstractThe yield response of forage maize (Zea mays L.) genotypes to plant density is not as clear as for grain hybrids, where density tolerant and sensitive types have been identified. A study including field trials, laboratory analyses, and in situ digestibility tests with one density‐tolerant and one sensitive hybrid was conducted with plant densities of 4 to 16 plants m−2. The investigations concentrated on stover. There are differences in sensitivity to planting density in forage maize yield. Differences between sensitive and tolerant genotypes in plant density range for maximum yield were 0.43 and 1.18 plants m−2 for grain and forage, respectively. The decreased sensitivity for grain compared with forage was 50.7 and 100.0% for the sensitive and the tolerant hybrid, respectively. It was not possible to separate the tolerant and sensitive hybrids in terms of total digestible nutrients (TDN), a measure of overall feed value. For plant densities lower than those required for maximum dry matter yield, there was a significant difference between the tolerant and the sensitive hybrid in TDN.