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You searched for: Publication Year 1973 Remove constraint Publication Year: 1973 Text availability Citation in PubAg Remove constraint Text availability: Citation in PubAg
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1. "Newer" trace elements in nutrition

Author:
Neilsen, F.H.; Hopkins, L.L.
Source:
Official proceedings of the annual meeting 1973 v.21st pp. 35-52
ISSN:
0569-2628
Subject:
Estimated Average Requirement; animal nutrition; growth and development; Adequate Intakes; animal reproduction; tin; bone mineralization; livestock; dietary nutrient sources; nutrient requirements; vanadium; nickel; cholesteremic effect; nutrition research; fluorine
Handle:
10113/48225

2. Abscission Processes in Cotton: Induction by Plant Water Deficit

Author:
B. L. McMichael; W. R. Jordan; R. D. Powell
Source:
Agronomy journal 1973 v.65 no.2 pp. 202-204
ISSN:
0002-1962
Subject:
Gossypium hirsutum; bolls; cotton; greenhouses; growth habit; juveniles; leaf abscission; leaf water potential; leaves; sand; water stress
Abstract:
... Premature boll shedding is characteristic of the cotton (Gossypium hirsutum L.) growth habit, but the extent of this shedding is quite variable. This study was undertaken to evaluate the effects of water stress on boll and leaf abscission. The experiments were conducted in a greenhouse using plants grown in pots containing sand. Plant water deficits were induced by withholding water. Leaf water po ...
DOI:
10.2134/agronj1973.00021962006500020005x

3. Absorption of 2,4-dichlorophenoxyacetic acid and 3-(p-chlorophenyl)-1,1-dimethylurea (Monuron) by barley roots

Author:
Donaldson, T.W.; Bayer, D.E.; Leonard, O.A.
Source:
Plant physiology 1973 v.52 no.6 pp. 638-645
ISSN:
0032-0889
Subject:
Hordeum vulgare; barley; roots; 2,4-D; monuron; uptake mechanisms
DOI:
10.1104/pp.52.6.638
PubMed:
16658621

4. Absorption of Mercuric Cation by Tannins in Agricultural Residues

Author:
A. C. Waiss; M. E. Wiley; J. A. Kuhnle; A. L. Potter; R. M. McCready
Source:
Journal of environmental quality 1973 v.2 no.3 pp. 369-371
ISSN:
0047-2425
Subject:
absorbents; absorption; agricultural wastes; bark; cations; grape pomace; heavy metals; hulls; ion exchange; manufacturing; mercury; mining; pectins; pollutants; tannins; wastewater
Abstract:
... Two common environmental pollutants are agricultural residues (skins, pits, husks, tannin bark, grape pomace) and waste streams of water containing only traces of heavy metals (such as mercury at 10 or more ppb) from mining or manufacturing operations. Agricultural residues contain tannins, polyphenolic substances, pectin, and other polymers—all with chemically reactive groups that can chelate, re ...
DOI:
10.2134/jeq1973.00472425000200030015x

5. Accumulated Heat Units for Classifying Corn Hybrid Maturity

Author:
H. J. Mederski; M. E. Miller; C. R. Weaver
Source:
Agronomy journal 1973 v.65 no.5 pp. 743-747
ISSN:
0002-1962
Subject:
Zea mays; climatic factors; corn; heat; phenology; plant development; planting date; prediction; seeds; Ohio
Abstract:
... Previous studies comparing the accumulated heat unit (AHU) method with the calendar day method for classifying corn (Zea mays L.) hybrids with respect to maturity do not clearly show the superiority of the AHU method over the calendar day method. They appear to have two limitations: (1) the range of climatic conditions under which the studies were conducted was not broad enough to elicit wide vari ...
DOI:
10.2134/agronj1973.00021962006500050020x

6. Accumulation of Dry Matter and Nitrogen Content of Burley Tobacco Growing in Fertilizer-induced Acid Soil

Author:
J. L. Sims; W. O. Atkinson
Source:
Agronomy journal 1973 v.65 no.5 pp. 762-765
ISSN:
0002-1962
Subject:
Nicotiana; acid soils; burley tobacco; dry matter accumulation; fertilizer rates; flowering; growing season; leaves; manganese; nitrogen compounds; nitrogen fertilizers; total nitrogen; toxicity
Abstract:
... Nicotiana tabarum L. cv. ‘Burley 21’ was grown in the field to determine the influence of rate of N fertilization on accumulation of dry matter and certain nitrogenous constituents during the growing season. Nitrogenous compounds in tobacco are presently of interest from a human health standpoint and the chemical constituents of tobacco leaves are known to be associated with dry matter accumulatio ...
DOI:
10.2134/agronj1973.00021962006500050026x

7. Accumulation of toxic levels of phosphorus in the leaves of phosphorus-deficient barley

Author:
Green, D.G.; Ferguson, W.S.; Warder, F.G.
Source:
Canadian journal of plant science 1973 v.53 no.2 pp. 241-246
ISSN:
0008-4220
Subject:
plant damage
DOI:
10.4141/cjps73-045

8. Accumulative Effects of Manure and N on Continuous Corn and Clay Soil. II. Chemical Changes in Soil

Author:
J. L. McIntosh; K. E. Varney
Source:
Agronomy journal 1973 v.65 no.4 pp. 629-633
ISSN:
0002-1962
Subject:
Zea mays; ammonium acetate; application rate; calcium; clay soils; corn; crops; dairy manure; exchangeable sodium; iron; magnesium; manganese; manure spreading; nutrient content; nutrient uptake; organic matter; pH; phosphorus fertilizers; potassium; sodium; soil amendments
Abstract:
... Continuous corn (Zea mays L.) was grown on a Panton clay soil (Typic Ochraqualf). Four rates of manure (0, 22, 44, and 66 tons/ha) and five rates of N (0, 56, 112, 168, and 224 kg/ha) were combined in a factorial arrangement and applied each year to the same plots. Also, 120 kg/ha of P and 90 kg/ha of K were applied for 4 years to all plots. Maintenance of structure and fertility had been difficul ...
DOI:
10.2134/agronj1973.00021962006500040030x

9. Acetylene-Reduction Assay of Anaerobic Nitrogen Fixation by Sediments of Selected Wisconsin Lakes

Author:
A. N. Macgregor; D. R. Keeney
Source:
Journal of environmental quality 1973 v.2 no.4 pp. 438-440
ISSN:
0047-2425
Subject:
acetylene reduction; enzyme inhibitors; lakes; methane; nitrogen fixation; nitrogenase; sediments; trophic levels; Wisconsin
Abstract:
... Sediments from two hardwater and six softwater lakes of varying trophic levels from Wisconsin were incubated under conditions which permitted continued synthesis of methane. Rates of acetylene reduction indicated that, on the average, sediments from hardwater and softwater lakes may fix 37 and 7.7 ng of N, respectively, per gram (dry weight) per day. The rate of acetylene reduction diminished in t ...
DOI:
10.2134/jeq1973.00472425000200040005x

10. Activation Analysis of Aluminum from Water Extract of Soil

Author:
U. K. Misra; E. R. Graham; W. J. Upchurch; D. M. McKown
Source:
Soil Science Society of America journal 1973 v.37 no.2 pp. 193-196
ISSN:
0361-5995
Subject:
aluminum; anion exchange resins; chlorides; gamma radiation; half life; leaching; lysimeters; manganese; nitrates; silica; silicon; soil water
Abstract:
... Determination of low-level Al in soil water extracts or lysimeter leachings requires a method extremely sensitive in the ppb range. ₁₃²⁷Al(n,γ)₁₃²⁸Al is rapid and convenient because it has a high cross section and a short half life. ²⁸Al may also be produced by ₁₄²⁸Si(n,p)₁₃²⁸Al. Hence a correction must be made by determining Si colorimetrially and finding the counts due to Si from a standard grap ...
DOI:
10.2136/sssaj1973.03615995003700020013x

11. Activity of Barley Seedling Roots as Measured by Strontium Uptake

Author:
J. M. Soileau
Source:
Agronomy journal 1973 v.65 no.4 pp. 625-628
ISSN:
0002-1962
Subject:
Hordeum vulgare; barley; calcium; crops; exchangeable calcium; fertilizers; greenhouses; magnesium; nutrient uptake; rhizosphere; root growth; roots; seedlings; soil depth; soil-plant interactions; strontium; strontium carbonate
Abstract:
... Root activity at various depths in soils is important in relation to effective use of lime and fertilizers by crops. Barley (Hordeum vulgare L.) seedlings were grown in presplit cylinders in the greenhouse to measure root activity in three 10-cm soil depth zones and to estimate daily rates of nutrient uptake. Twenty-five seedlings were planted per 15 ✕ 30 cm cylinder containing 6.5 kg of soil. SrC ...
DOI:
10.2134/agronj1973.00021962006500040029x

12. The Activity of Individual Molecules of Hybrid β-Galactosidase Reconstituted from the Wild-Type and an Inactive-Mutant Enzyme

Author:
Melchers, Fritz; Messer, Walter
Source:
European journal of biochemistry 1973 v.34 no.2 pp. 228-231
ISSN:
0014-2956
Subject:
Escherichia; active sites; beta-galactosidase; enzyme activity; hybrids; mutants
Abstract:
... A technique capable of detecting individual molecules of β-galactosidase has been used to measure the enzyme activity of single hybrid β-galactosidase molecules reconstituted from mixtures of varying proportions of wild-type and lac⁻ aba mutant enzyme. Reconstituted molecules exhibit activities of 0, 1/4, 2/4, 3/4, 4/4 of the wild-type enzyme, depending on the ratio of wild-type to mutant subunits ...
DOI:
10.1111/j.1432-1033.1973.tb02750.x

13. Adaptive Variation in Size of Cricket Frogs

Author:
Eviatar Nevo
Source:
Ecology 1973 v.54 no.6 pp. 1271-1281
ISSN:
0012-9658
Subject:
Acris crepitans; Neobatrachia; biogeography; body size; body weight changes; climate; correlation; frogs; geographical variation; grasslands; humidity; jumping; longitude; predation; rain; regression analysis; sibling species; temperature; variance; woodlands; North America
Abstract:
... Geographic variation in body size (BL) and relative foot size (F/B) was studied across the ranges of two sibling species of cricket frogs, genus Acris (Hylidae)in North America. Acris crepitans has a large range in eastern and central states extending from mesic woodlands to xeric grasslands, whereas A. gryllus has a limited range in southeastern states in mesic woodlands. Measurements of BL and F ...
DOI:
10.2307/1934189

14. Adaxial and Abaxial Stomatal Resistance of Cotton in the Field

Author:
Peter J. H. Sharpe
Source:
Agronomy journal 1973 v.65 no.4 pp. 570-574
ISSN:
0002-1962
Subject:
Gossypium hirsutum; ambient temperature; cotton; drought; lysimeters; soil water; stomata; stomatal conductance; stomatal movement; water stress; Australia
Abstract:
... An experiment was conducted near. Sydney, Australia to determine the adaxial and abaxial stomatal responses of cotton (Gossypium hirsutum L.) to environmental factors under noncycling field conditions. Cotton plants were grown in small lysimeter pans and transpiration was measured by strain guage lysimeters. Leaf temperature, ambient temperature and other micrometeorological parameters were monito ...
DOI:
10.2134/agronj1973.00021962006500040014x

15. Aerodynamic and Energy Balance Comparisons Between Awned and Nonawned Barley

Author:
J. F. Benci; J. K. Aase; A. H. Ferguson
Source:
Agronomy journal 1973 v.65 no.3 pp. 373-377
ISSN:
0002-1962
Subject:
Hordeum vulgare; aerodynamics; awns; barley; canopy; energy balance; heat transfer; isogenic lines; latent heat; net radiation; roughness length; turbulent flow
Abstract:
... The objective of the study was to evaluate the influence of awning characteristics of barley (Hordeum vulgare L.) on the partitioning of the heat load and the turbulent characteristics of the lower atmospheric boundary associated with the plant canopy. Aerodynamic studies of full-awned, half-awned, and nonawned isogenic barley indicated that awns increased the roughness length for the barley canop ...
DOI:
10.2134/agronj1973.00021962006500030008x

16. Agricultural Chemicals in Surface Runoff, Ground Water, and Soil: I. Endrin

Author:
G. H. Willis; R. A. Hamilton
Source:
Journal of environmental quality 1973 v.2 no.4 pp. 463-466
ISSN:
0047-2425
Subject:
Saccharum officinarum; agrochemicals; application rate; endrin; groundwater; rain; runoff; soil; sugarcane
Abstract:
... Endrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4, 4a,5,6,7,8,8aoctahydro-1,4-endo, endo-5,8-dimethanonapthalene) was surface applied at a rate of 0.337 kg/ha to sugarcane (Saccharum officinarum L.) plots instrumented to sample surface runoff and ground water. Runoff, ground water, and soil sampleswere collected over a 2-year period and analyzed for endrin. Only small amounts of endrin were lost annu ...
DOI:
10.2134/jeq1973.00472425000200040012x

17. Agronomic Potential of Nectariless Cotton

Author:
William R. Meredith; C. D. Ranney; M. L. Laster; R. R. Bridge
Source:
Journal of environmental quality 1973 v.2 no.1 pp. 141-144
ISSN:
0047-2425
Subject:
Coccinellidae; Gossypium hirsutum; Lygus lineolaris; agronomic traits; cotton; fiber quality; genetic variation; leaves; nectaries; predatory insects; river deltas; yield components
Abstract:
... We compared three BC₆F₄ nectariless strains of cotton (Gossypium hirsutum L.) with their recurrent parent varieties for yield, yield components, and fiber properties at six environments in 1971. A slight decrease (4.3%) in yield for nectariless ‘Stoneville 7A’ and a slight increase (3.8%) in yield for nectariless ‘Deltapine Smooth Leaf’ was detected. Nectaried and nectariless ‘Dixie King’ did not ...
DOI:
10.2134/jeq1973.00472425000200010026x

18. Air Entrapment as a Possible Source of Error in the Use of a Cylindrical Heat Probe

Author:
N. K. Nagpal; L. Boersma
Source:
Soil Science Society of America journal 1973 v.37 no.6 pp. 828-832
ISSN:
0361-5995
Subject:
air; ambient temperature; glass; heat; particle size; porous media; sieving; soil water; soil water content; thermal conductivity; water content
Abstract:
... The cylindrical heat probe is frequently used to measure the thermal conductivity of soils. Its theory is based on the assumption of zero thermal contact resistance at the probe surface. Noncompliance with this assumption could result from air entrapment at the probe surface, at the time of inserting the probe into the porous material. Results of studies are reported which show that the use of the ...
DOI:
10.2136/sssaj1973.03615995003700060014x

19. Air Temperature, Heat Sums, and Pollen Shedding Phenology of Longleaf Pine

Author:
William D. Boyer
Source:
Ecology 1973 v.54 no.2 pp. 420-426
ISSN:
0012-9658
Subject:
Pinus palustris; air temperature; heat sums; phenology; pollen; trees; Alabama; North Carolina
Abstract:
... Between 1957 and 1966, pollen shedding by longleaf pine (Pinus palustris Mill.) in southwestern Alabama peaked at dates ranging from February 23 to April 3. January 1 and 50 degrees F was the combination of starting date and threshold air temperature that minimized annual variations in heat sums before the trees flowered. The heat sum required for peak pollen shedding declined as the season advanc ...
DOI:
10.2307/1934351

20. Allocation of Scarce Resources to Agricultural Research: Review of Methodology

Author:
C. Richard Shumway
Source:
American journal of agricultural economics 1973 v.55 no.4_Part_1 pp. 557-566
ISSN:
0002-9092
Subject:
agricultural economics; agricultural research; models; quantitative analysis; research management; resource allocation
Abstract:
... With an increasing stress on research budgets, the impetus for investigation of alternative models for managing research is growing. Much work has been invested already in technique development. To precede additional research, the current state‐of‐the‐art in resource allocation methodology pertinent to agricultural research management is presented. The focus is on quantitative approaches for impro ...
DOI:
10.2307/1238340