bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Subsurface Irrigation and Organic Additions on Top and Root Growth of Field Corn1
Authors: Mitchell W. H. , Sparks D. L. 
Published: July 2010

AbstractNumerous attempts have been made to increase root proliferation by modifying soil profiles possessing undesirable chemical and physical properties.Field and laboratory studies were conducted over a 5‐year period on an Evesboro loamy sand (mesic, coated Typic Quartzipsamments) soil from Delaware to determine the effect of organic additions and type of irrigation on corn (Zea mays L.) grain yield, root distribution, and on selected soil properties. The study also sought to determine if organic additions would increase the effectiveness of subsurface irrigation. Organic additions, made only in the 1st year of the study, consisted of 10 ✕ 40 cm chisel (C) openings at 76 cm intervals which were filled with solid waste (SW) and/or poultry manure (PM) at 65 metric tons/ha. No attempt was made to superimpose corn rows directly above the chisel openings. Irrigation types were subsurface (SSI), and trickle irrigation (TI). Grain yields were significantly higher in C + SSI than in C + TI treatments. Chiseling + SSI increased the average 5‐year corn yield 4,300 kg/ha over C alone which demonstrated the pronounced effect that SSI had on yield. Organic additions had no signifciant effect on grain yields, although yields for the C + SW treatment were numerically higher than for the C + PM treatment each year of the study, and the former averaged 1,150 kg/ha higher over the 5‐year period. The C + SW treatments also produced higher yields than the control (NC). Chiseling, without incorporation of organic materials (C) was no more effective than leaving the soil undisturbed (NC). Organic additions enhanced root growth more than yield of corn. The subsoil was essentially devoid of roots without chiseling or organic additions. The highest CEC and organic matter levels at the end of the 5‐year study were found in the organic addition trench adjacent to the SSI lines. Corn roots proliferated in this region and in most cases enveloped the irrigation lines. Lateral as well as vertical movement of Ca, K, Mg, and P occurred with the lowest concentrations occurring in the plow layer. Movement of plant nutrients laterally from the organic addition trench into the surrounding subsoil probably contributed to root extension and could be significant in terms of nutrient utilization.
Urease Activity in a Kentucky Bluegrass Turf1
Authors: Torello W. A. , Wehner D. J. 
Published: July 2010

AbstractThe components of a turfgrass ecosystem, including plants, an intervening layer of thatch and the underlying soil, influence the fate of topically applied urea fertilizer. The loss of urea N by ammonia volatilization may be governed by the rate of urea hydrolysis. The main objective of this study was to determine the extent of urease activity associated with turfgrass plant tissue, thatch, and the underlying soil. This information may help elucidate the mechanism of ammonia loss following urea application. Because a turfgrass stand frequently possesses an extensive thatch layer that may serve as the primary plant growth medium, additional objectives included. i) determining the effects of air drying and seasonal variation on the activity of urease in thatch; ii) determining the variability in thatch urease activity by analyzing multiple field samples; and iii) determining the variation of urease activity within a thatch profile. Turfgrass clippings, thatch, and underlying Flanagan silt loam soil (Aquic Argiudoll) samples were taken from a field‐grown Kentucky bluegrass (Poa pratensis L.) turf in either September 1980 or March 1981. On a dry weight basis, urease activity was 18 to 30 times higher from turfgrass clippings and thatch than from soil. Air drying thatch increased urease activity by 20% over moist samples while air drying soil samples had no apparent effect. Greenhouse incubation of winterdormant thatch samples increased urease activity 40 %, presumably in response to the duration of increased temperature. Thatch urease activity varied between sampling sites but still remained extremely high compared to soil activity. Within each thatch sample (1 × 1 × 2 cm), urease activity was highest in the upper 1.0 cm of the profile. It was concluded that thatch urease activity was variable in nature depending upon seasonal conditions which contrasts sharply with extremely stable soil urease activities. These findings suggest that, because of the high level of urease in thatch, ammonia volatilization will occur from most urea‐treated turfgrass stands, regardless of the type of underlying soil unless the urea is thoroughly washed into the soil.
Herbicide and Planting Date Influence Establishment of Sod‐Seeded Alfalfa1
Authors: Martin N. P. , Sheaffer C. C. , Wyse D. L. , Schriever D. A. 
Published: July 2010

AbstractYield and quality of perennial grass pastures can be improved through sod‐seeding of alfalfa (Medicago sativa L.). Herbicides have been widely used for grass suppression in sod‐seeding; however, the influence of the time of application on herbicide effectiveness requires study. Our objective was to determine the effects of planting dates and rates and types of herbicides on alfalfa establishment and yield when interseeded into perennial grass sod. A field study was conducted for 2 years on a Typic Halaquol, fine loamy, over sand, mixed, mesic soil. Alfalfa was sod‐seeded into a mixed smooth bromegrass (Bromus inermis Leyss.), Kentucky bluegrass (Poa pratensis L.), and quackgrass (Agropyron repens L.) sod on 21 April, 10 May, 19 May, and 2 June in 1978; and 19 April, 4 May, 21 May, and 2 June in 1979. On each planting date, paraquat (1,1′‐dimethyl‐4,4′‐bipyridinium ion) and glyphosate [N‐(phosphonomethyl) glycine] were each broadcast sprayed at 0.6, 0.8, and 1.1 kg ha−1. Dalapon [2,2‐dichloropropionic acid] was broadcast sprayed at 3.4, 5.6, and 9.0 kg ha−1. Greatest seeding year legume yields were obtained with the medium or high dalapon rates for the April seeding dates or with the medium or high glyphosate rates for the late May seeding date. The lowest average legume yields across all herbicides occurred for the June seeding date each year. Dalapon was the most effective herbicide across all rates for suppressing grass and increasing alfalfa yields for the April planting dates each year when grass regrowth was limited. For the early May planting date, dalapon treatments had the lowest grass yields. Alfalfa yields for dalapon and glyphosate treatments were not consistently different. For the late May planting date, glyphosate provided the greatest grass suppression and alfalfa yields. Herbicides and herbicide rates can be selected for grass suppression and legume establishment based on extent of grass vegetative development. Under low rainfall conditions, grass suppression may not insure successful legume establishment.
Agronomic, Chemical, and Smoke Characteristics of Flue‐cured Tobacco Lines with Different Levels of Total Alkaloids1
Authors: Chaplin James F. , Burk L. G. 
Published: July 2010

abstractTotal alkaloids (predominately nicotine) are important constitutents in flue‐cured tobacco (Nicotiana tabacum L.). Due to varying nicotine levels in cigarettes, it is of interest to see what effect varying alkaloid levels in tobacco have on certain agronomic and chemical characteristics of the cured leaf. Experiments were conducted at two locations to develop lines of flue‐cured tobacco with different levels of total alkaloids and to evaluate these lines for agronomic, chemical, and smoke characteristics. Three flue‐cured cultivars with different total alkaloid levels were chosen as recurrent parents. The parents and alkaloid levels were: 'Coker 139' (1.88%), 'NC 95' (3.28%), and 'SC 58' (4.51%). Each cultivar was crossed with a low alkaloid line (0.20%). After the initial cross, backcrosses were made in each F2population between a low alkaloid plant and its respective recurrent parent. BC5F7generation plants with different levels of total alkaloids were selected and advanced to the BC5F7to obtain stable lines. Also dihaploids were developed from BC5F7plants and lines with different levels of total alkaloids were selected. Both the BC5F7and dihaploid populations were evaluated. Based on these tests the line with the highest yield and grade index at each alkaloid level was further evaluated for total alkaloids, reducing sugars, yield, grade index, days to flower, plant height, and number of leaves per plant. Lines with the following levels of total alkaloids were evaluated: NC 95 family ‐ 0.34, 1.08, 2.05, 3.11, and 3.55%; SC 58 family ‐ 0.38, 1.59, 1.90, 2.82, 4.18, and 4.82%; and the Coker 139 family ‐ 0.20, 0.93,1.66,1.84, and 2.17%. The 1.08% line in the NC 95 and 1.59% line in the SC 58 families were dihaploids. None of the lines converted appreciable amounts of nicotine to nornicotine. Therefore, the total alkaloid levels reflected predominantly nicotine. In most families the high alkaloid lines gave the highest grade index. Days to flower, plant height, and number of leaves per plant were not associated with total alkaloid levels in cured leaf. Cigarette smoke from the different tobacco lines was evaluated by two smoke panels. The results from Panel A indicated that it was difficult to associate any of the taste parameters with levels of total alkaloids in the leaf. The results from Panel B indicated that an increase in total alkaloids in the leaf was accompanied by an increase in flavor of the smoke.
Reaction of a Resistant and a Susceptible Corn Hybrid to Various Southwestern Corn Borer Infestation Levels1
Authors: William W. Paul , Davis Frank M. 
Published: July 2010

AbstractInfestation of corn (Zea maysL.) by the southwestern corn borer [Diatraea grandiosella(Dyar)] can result in substantial losses. Corn genotypes with resistance to leaf feeding damage by the southwestern corn borer have been developed; however, no data on the effectiveness of this resistance in preventing yield and plant height reductions have been reported. To compare the effects of varying infestation levels on a leaf‐feeding‐resistant and a leaf‐feeding‐susceptible corn hybrid, plants in the 10 to 12 leaf stage of growth were infested with 0 to 40 southwestern corn borer larvae per plant in a field study grown on a Leeper silty clay loam (fine, montmorillonitic, nonacid, thermic, Vertic Haplaquepts) in 1982 and 1983. Plants were evaluated for leaf feeding damage, height, and grain yield. Infestation of the susceptible hybrid with 0 to 40 larvae per plant resulted in a linear decline in plant height and yield as infestation level increased. Infestation with 40 larvae per plant reduced yield 39%. Conversely, neither plant height nor yield of the resistant hybrid was significantly reduced at any infestation level. The level of resistance found in the resistant hybrid was, therefore, adequate to prevent losses.
Persistence of Selected Tropical Pasture Legumes in Peninsular Florida1
Authors: Pitman W. D. , Kretschmer A. E. 
Published: July 2010

AbstractThe potential N contribution of tropical legumes to grass pastures on the infertile soils of Peninsular Florida necessitates increased efforts to develop suitable pasture legumes. Nineteen accessions representing 17 tropical legume species were evaluated for persistence under grazing in bahiagrass swards on a Peninsular Florida Arenic Haplaquod (Spodosol) soil. After three growing seasons in the mixed grass‐legume swards, only Vigna parkeri Bak. and aeschynomene (Aeschynomene americana L.) covered larger areas than were originally planted. Indications of potential adaptation to flatwoods pastures were also obtained with ‘Florida’ carpon desmodium [Desmodium heterocarpon (L.) DC], phasey bean [Macroptilium lathyroides (L.) Urb.], Vigna adenantha (G.F. Meyer) Marechal, Mascherpa, and Stainier and Vigna luteola (Jacq.) Benth. However, the variation in response of these four accessions among field replications indicates that site and management requirements of these legumes need further investigation.
Effect of N Fertilizer on Protein Content of Grain, Straw, and Chaff Tissues in Soft White Winter Wheat1
Authors: Glenn D. M. , Carey A. , Bolton F. E. , Vavra M. 
Published: July 2010

AbstractNitrogen management programs of soft white winter wheat (Triticum aestivum L.) in semiarid regions are generally based upon soil tests of available water and residual N levels. The purpose of this work was to develop postharvest criteria for N‐sufficiency and N‐insufficiency based on tissue protein levels as it relates to maximum grain yield in a fallow‐wheat rotation. Yield‐protein relationships in grain, straw, and chaff tissues were examined in field trials from 4 harvest years on a Walla Walla silt loam (coarse‐silty, mixed, mesic, Typic Haploxeroll). Grain protein content was a better postharvest indicator of N sufficiency for maximum grain yield than straw or chaff protein levels. Excessive weed growth confounded this relationship in 1 year. Using a chi‐square interaction procedure, a critical level of 8.8% grain protein was determined necessary for N sufficiency in ‘Stephens’ soft white winter wheat when weed growth was not a management problem. The transition zone between N sufficient and N insufficient responses was between 8.3 and 9.1% grain protein. The amount of relative yield lost to N insufficiency was related to grain protein content. There was a 9.8% yield reduction for each grain protein percentage below 9.1. Critical protein values indicative of N insufficiency could not be determined for straw and chaff tissues. Straw and chaff protein levels greater than 2.6 and 3.5%, respectively, were exclusively associated with N sufficiency.
Seed Density and Seed Size of Pearl Millet as Related to Field Emergence and Several Seed and Seedling Traits1
Authors: Lawan M. , Barnett F. L. , Khaleeq B. , Vanderlip R. L. 
Published: July 2010

AbstractPearl millet, Pennisetum americanum(L.) Leeke, is often established under stressful environmental conditions. Thus, establishment capability is crucial to success of the crop. Objectives of this study were (i) to verify previous results associating establishment of the crop with density and size of seed, and (ii) to identify other seed and seedling traits of pearl millet that are related to seed density and size. Seed of four populations was divided by gravity table into three density fractions, each of which was then separated, by dockage sieves, into three size fractions. Seed representing each population‐density size fraction was evaluated in a field study at Manhattan, KS in 1981 and in the laboratory. Seedling emergence increased from 40% with small, low‐density seed, to 62% with large, high‐density seed. Days from seeding to anthesis decreased from 70 with small, low‐density seed, to 62 with large, high‐density seed. In both cases, density and size interacted in such a manner that each factor had most effect at low levels of the other. Seed weight, a germination index that emphasized speed of germination, and seed diameter were positively affected by both seed density and size. In addition, germination, seedling height 24 days after seeding, and proportion of vitreous starch in seed endosperm were positively related to seed density. Seedling respiration rate, on a per‐seed basis, was associated positively with seed density and size. With a fixed weight of seed, however, there was little effect. Results indicated that seed density and seed size were effective criteria of field establishment and of seed quality as determined by a number of laboratory tests. In some cases, however, the nature of the density × size interaction implied that the major effects of both factors were effectively integrated in seed weight.
Suppression of Anthracnose and Phomopsis Seed Rot on Soybean with Potassium Fertilizer and Benomyl1
Authors: Sij J. W. , Turner F. T. , Whitney N. G. 
Published: July 2010

AbstractRecent studies linking K with less disease in certain crops have stimulated interest in the beneficial aspects K may play in plant disease protection. The objectives of this 3‐yr study were to evaluate the role of K fertilizer on anthracnose [Colletotrichum dematium(Pers. ex Fr.) Grove var. truncatum(Schw.) Arx.] and phomopsis seed rot (Phomopsissp.) development in field‐grown soybean plants [Glycine max(L.) Merr.] and to measure the interaction of foliar‐applied benomyl fungicide with soil‐applied K fertilizer. The soil, a Typic Agriaquoll, contained low (215 to 278 kg/ha) and high (11 to 96 kg/ha) levels of available K and P, respectively. The experiments included six levels of K, three levels of P fertilizer, and two levels of benomyl fungicide on ‘Davis’ soybean harvested at maturity and 4 weeks later. Anthracnose disease ratings decreased significantly as K rates increased to the maximum of 450 kg/ha. Benomyl and K + benomyl reduced anthracnose substantially more (about 60%) than did K alone. The action of K fertilizer on anthracnose control appeared to be additive to that afforded by benomyl when the soil contained low to medium K. Increasing K fertilizer significantly increased soybean yield by about 700 kg/ha when 220 kg/ha of K fertilizer was applied. Application of benomyl provided an additional yield increase of about 300 kg/ha except at the highest K level. Increasing K up to 330 kg/ha reduced delayed harvest yield losses caused by shattering and weathering. Benomyl and K + benomyl treatments minimized delayed harvest losses, which peaked at a K level of about 220 kg/ha. Phosphorus fertilizer failed to increase yield or prevent shattering. Increasing K reduced Phomopsissp. in first‐harvest seed from 35% to about 1% and in second‐harvest seed from about 52 to 28% in plots receiving no K fertilizer and 450 kg/ ha of K, respectively. The addition of benomyl suppressed this pathogen further in first‐harvest seed from 12% infected seed to 1% and in second‐harvest seed from 40 to 18% in plots receiving no K fertilizer and 450 kg/ha of K, respectively. Phosphorus, however, appeared to slightly enhance Phomopsissp. development. The effects of residual fertilizer on anthracnose development and yield were evident the following soybean growing season. Although pathogen pressure and environmental conditions play a major role in disease development in soybean, it should be recognized that soil K level can also be an influencing factor.
Comparison of Methods of Enriching a Soil with Nitrogen‐15 to Estimate Dinitrogen Fixation by Isotope Dilution1
Authors: Rennie R. J. 
Published: July 2010

AbstractA 2‐yr field comparison of methods of labeling the soil with 15N was undertaken to increase the precision of estimating N2fixation by the 15N isotope dilution procedure. Dinitrogen fixation was estimated using ‘Aurora’ field bean (Phaseolus vulgarisL.) grown on a Chin loam (Typic Haploboroll) soil under irrigation in southern Alberta. Postemergence fluid injection of (15NH4)2SO4into the rooting zone of 1‐week‐old plants (with or without the nitrification inhibitor N‐Serve) resulted in excellent experimental precision and greater planning flexibility. It was superior to preemergence addition of liquid 15N in broadcast or banded form because of the high winds often encountered in the spring. The preemergence addition of low‐level 15N‐labeled legume or cereal organic residues compared favorably with mineral N addition and had the advantage that residues from previous 15N experiments could be utilized cost‐free. Isotope dilution of 15N at levels of natural isotopic abundance resulted in similar estimates of N2fixation with no consistent evidence of isotopic discrimination and appears promising as an inexpensive but qualitative screening procedure for field selection of N2fixation by legume breeders.
Composition of Leaf Protein Concentrate and Deproteinized Juice from Alfalfa, Red Clover, and Birdsfoot Trefoil1
Authors: Collins Michael 
Published: July 2010

AbstractLosses during field wilting of silage and curing of hay reduce both yield and quality. Direct harvest and mechanical dewatering avoid these losses and produce a protein concentrate. A 2‐year field experiment was conducted to evaluate legume species and harvest date effects on the yield and composition of the protein concentrate and deproteinized juice fractions from spring growth legume herbage. The soil was a Plano silt loam (fine‐silty, mixed, mesic Typic Argiudoll). Alfalfa (Medicago sativa L.) protein concentrate averaged 201 g dry matter (DM) kg−1 total mass, slightly higher than red clover (Trifolium pratense L.) and birdsfoot trefoil (Lotus corniculatus L.). Harvest date effects on DM concentration in both the protein concentrate and the deproteinized juice were significant but showed little relationship to shoot maturation stage. Alfalfa protein concentrate averaged 102 g N kg−1 DM, which was more N than the protein concentrate from red clover and birdsfoot trefoil in 1981 but not in 1980. Harvest date effects were small for alfalfa protein concentrate N concentration but red clover and birdsfoot trefoil had less of that constituent on the last harvest date. Total nonstructural carbohydrate (TNC) was highest in the deproteinized juice from red clover, which had 327 g TNC kg−1 DM, followed by birdsfoot trefoil and alfalfa with the lowest concentrations. Harvest date effects on TNC differed among species, but these differences were not large enough to be of practical importance. Alfalfa and red clover whole crops differed in the concentrations of several amino acids, but they differed less than the whole crop differed from the pressed forage and protein concentrate fractions within each species. Red clover protein concentrate had more threonine and valine than alfalfa protein concentrate but only 85% as much methionine, 52% as much cystine and less isoleucine. Results of this 2‐yr experiment indicate that N and DM concentrations differ in protein concentrates from different perennial legumes. Amino acid concentrations in protein concentrate were generally less affected by species and maturation than the same constituents in the whole crops. Species differences in deproteinized juice TNC concentrations were substantial and should be considered in the development of mechanical dewatering systems.
Effects of Timing of Nitrogen Fertilization and a Fungicide on Soft Red Winter Wheat1
Authors: Roth G. W. , Marshall H. G. 
Published: July 2010

AbstractSplit spring N applications and fungicides are important components of proposed intensive management systems for soft red winter wheat (Triticum aestivum L.). Six experiments at two locations were conducted on Hagerstown silt loam (fine, mixed, mesic Typic Hapludalf) soils to evaluate the responses of wheat to a fungicide and delayed or split N applications. Delayed N treatments consisted of a single application of 100 kg ha−1 at either growth stage (GS) 5 or 8. Seven split N treatments consisted of two or three applications made at GS 3, 5, or 8, totaling 100 kg N ha−1. Split and delayed N responses were compared to those resulting from four rates of N applied at GS 3. Average grain yields for the experiments ranged from 3.2 to 5.9 Mg ha−1. Yields from split and delayed N were greater than the maximum achieved with GS 3 N applications in only one of the six experiments. In this experiment, the greatest yield increase due to split N, 0.7 Mg ha−1, occurred when a fungicide was used. A large amount of precipitation (219 mm) at that location between GS 3 and GS 5, and a high fertilizer N requirement apparently contributed to the response to split N. Yield responses to fungicides (triadimefon [l‐(4‐chlorophenoxy)‐3,3‐dimethyl‐l‐(lH‐l,2,4‐trizol‐1‐yl)‐2‐butanone] or triadimefon + mancozeb [zinc ion and manganese ethylene bisdithiocarbamate)) varied between years and ranged from 0 to 0.9 Mg ha−1. Decisions to use split N and fungicides should be based on factors such as disease severity, rainfall, and anticipated soil N supplying capability.