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You searched for: Journal name Agronomy journal Remove constraint Journal name: Agronomy journal Publication year rev 8020-1980 Remove constraint Publication year rev: 8020-1980 Text availability Citation in PubAg Remove constraint Text availability: Citation in PubAg
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1. A Computational Approach for Water Culture

Author:
J. Ben Asher; J. M. Gordon; J. Gale; R. Kopel
Source:
Agronomy journal 1980 v.72 no.4 pp. 640-645
ISSN:
0002-1962
Subject:
Solanum; agronomy; crop production; eggplants; enzymes; equations; mass flow; mathematical models; nitrates; nutrient content; nutrient uptake; research and development; root systems; water flow
Abstract:
... Water culture methods for commercial crop production are now under research and development. Experiments have been performed primarily to investigate methods for preparing nutrient solutions. The objective of this study, however, was to develop a physical model for a water culture system. A study of nutrient uptake by egg plant (Solanum melunogenn L. var. esculentum) as a function of both the solu ...
DOI:
10.2134/agronj1980.00021962007200040017x

2. A Method for Obtaining Undisturbed Samples from Soil Columns

Author:
S. Mulchrone; M. A. Morgan; G. J. Mullen
Source:
Agronomy journal 1980 v.72 no.1 pp. 170-172
ISSN:
0002-1962
Subject:
agronomy; bulk density; drainage; drainage water; mineral soils; peat; seals; water table
Abstract:
... Lack of a suitably simple technique to study the fate of nutrients applied to soil columns of given bulk density and water-table exposure prompted the development of the apparatus described here. The system has a split pipe, containing the soil column, housed in an outer jacket. Peat or mineral soil can be packed into the split pipe to pre-selected bulk density values which vary little with depth. ...
DOI:
10.2134/agronj1980.00021962007200010035x

3. A Retractable, Neutron-Probe Access Tube

Author:
D. M. Glenn; R. L. Henderson; F. E. Bolton
Source:
Agronomy journal 1980 v.72 no.6 pp. 1067-1068
ISSN:
0002-1962
Subject:
crop rotation; fallow; harrows; neutron probes; planters; planting; soil water; tillage
Abstract:
... Soil moisture measurements with a neutron-probe moisture meter provide a rapid and non-destructive means for measuring soil water in long-term studies. The inability of farm machinery to pass over the extended access tube limits its use in some situations. A retractable, neutronprobe access tube was designed to allow implement passage at the normal speed and tillage depth without contacting the ac ...
DOI:
10.2134/agronj1980.00021962007200060050x

4. A Screen-Caged Thermocouple Psychrometer and Calibration Chamber for Measurements of Plant and Soil Water Potential

Author:
Ray W. Brown; James M. Collins
Source:
Agronomy journal 1980 v.72 no.5 pp. 851-854
ISSN:
0002-1962
Subject:
calibration; condensation (phase transition); evaporation; psychrometers; soil sampling; soil water; soil water potential; temperature profiles; vapors
Abstract:
... Estimates of water potential with thermocouple psychrometers are subject to errors due to temperature gradients. The objective here is to describe the design and construction procedures of a new screen-cage single-junction psychrometer that minimize these errors. The screen-cage design restricts entry of contaminants into the psychrometer cavity; allows rapid vapor equilibration between the sample ...
DOI:
10.2134/agronj1980.00021962007200050036x

5. A Small Plot Drag for Use on Bermudagrass or Similar Sods

Author:
T. C. Keisling; Edwin Holt
Source:
Agronomy journal 1980 v.72 no.6 pp. 1063-1064
ISSN:
0002-1962
Subject:
Cynodon dactylon; agronomy; pastures
Abstract:
... Many types of drags and spike tooth harrows have been used in pasture work. Most are not suitable for small plot work with bermudagrass because of lack of uniformity resulting from the dragging operation, fouling and clogging of the teeth with plant parts, and their cumbersome operation. This note describes a small unit which drags a plot uniformly, exhibits essentially no fouling or clogging of t ...
DOI:
10.2134/agronj1980.00021962007200060047x

6. Absorption and Translocation of Chromium through the Surface of a Soybean Leaf

Author:
D. J. Pickrell; B. G. Ellis
Source:
Agronomy journal 1980 v.72 no.5 pp. 854-855
ISSN:
0002-1962
Subject:
EDTA (chelating agent); Glycine max; absorption; animals; autoradiography; chromium; iron; leaves; metabolism; roots; soybeans
Abstract:
... Although Cr is known to be important in animal metabolism, it does not readily translocate through the roots of most plants. The addition of Cr to plant leaves as a spray material is a possible method of increasing the Cr content of plants. The objective of this laboratory study was to determine if Cr would be absorbed by a plant leaf and translocated to other portions of the plant. A single drop ...
DOI:
10.2134/agronj1980.00021962007200050037x

7. Adaptation of Cotton Genotypes to an Acid, Aluminum Toxic Soil

Author:
C. D. Foy; J. E. Jones; H. W. Webb
Source:
Agronomy journal 1980 v.72 no.5 pp. 833-839
ISSN:
0002-1962
Subject:
Gossypium hirsutum; Hapludults; acid soils; acidity; agronomy; aluminum; cotton; drought; economic feasibility; greenhouses; pH; subsoil; toxicity; Southeastern United States
Abstract:
... Aluminum toxicity, associated with subsoil acidity, limits rooting depth of cotton (Gossypium hirsutum L.) in certain soils of the southern U.S. Shallow rooting means greater susceptibility to drought and less effective use of subsoil nutrients. Liming subsoil to detoxify A1 is difficult and often not economically feasible. An alternative or supplemental approach is to select or breed cotton genot ...
DOI:
10.2134/agronj1980.00021962007200050032x

8. Afternoon Water Deficits and Grain Yields in Old and New Soybean Cultivars

Author:
J. S. Boyer; R. R. Johnson; S. G. Saupe
Source:
Agronomy journal 1980 v.72 no.6 pp. 981-986
ISSN:
0002-1962
Subject:
Glycine max; agronomy; canopy; cultivars; leaves; photosynthesis; plant available water; soybeans; Illinois
Abstract:
... Plant water deficits affect many metabolic processes, and soybean (Glycine max L. Merr.) is subject to water deficits during midday even when soil water is adequate under field conditions. Our objective was to determine if yield improvement by plant breeding has been associated with avoidance of these deficits in soybean. A 3- year experiment was conducted on highly productive soils in central Ill ...
DOI:
10.2134/agronj1980.00021962007200060028x

9. Air Pollution Oxidant Effects on Cool-Season and Warm-Season Turfgrasses

Author:
V. B. Youngner; F. J. Nudge
Source:
Agronomy journal 1980 v.72 no.1 pp. 169-170
ISSN:
0002-1962
Subject:
Agrostis capillaris; Cynodon dactylon; Festuca rubra; Poa pratensis; air; air pollutants; air pollution; cold season; cultivars; greenhouses; leaves; nitrates; oxidants; ozone; turf grasses; urban areas; warm season; warm season grasses
Abstract:
... Although turfgrasses are grown extensively in urban areas where air pollution is a problem, little is known about their reaction to air pollutant oxidants. Cultivars of common turfgrass species were started in a greenhouse with charcoal-filtered air. One lot of each was fumigated with 0.50 ppm ozone and another with 0.50 ppb peroxyacetyl nitrate (PAN) for 3 hours. A third lot was retained in the g ...
DOI:
10.2134/agronj1980.00021962007200010034x

10. Ameliorative Role of Zn, K, and Gypsum on Maize Growth under Alkali Soil Conditions

Author:
U. C. Shukla; A. K. Mukhi
Source:
Agronomy journal 1980 v.72 no.1 pp. 85-88
ISSN:
0002-1962
Subject:
Zea mays; agronomy; antagonism; corn; dry matter accumulation; greenhouse experimentation; gypsum; plant growth; soil; yields; zinc
Abstract:
... Information is needed on the ameliorative role of Zn in relation to gypsum and K on plant growth under alkali soil conditions. A greenhouse experiment was conducted, growing maize (Zea mays L.) as an indicator crop for 45 days. Treatment combinations of three levels of Zn (0, 5, 10 ppm), and three levels of K (0, 50, 250 ppm) were superimposed on a normal, an alkali, and a gypsum-treated alkali so ...
DOI:
10.2134/agronj1980.00021962007200010017x

11. Ammonia Exchange at the Land Surface

Author:
Edgar Lemon; Raymond Van Houtte
Source:
Agronomy journal 1980 v.72 no.6 pp. 876-883
ISSN:
0002-1962
Subject:
Elymus repens subsp. repens; Glycine max; Medicago sativa; absorption; agronomy; air; alfalfa; ammonia; biosphere; computer simulation; nitrogen fixation; soil; vegetation; wind
Abstract:
... Studies of NH₃ exchange between plant leaves and air have mostly been made in controlled chambers where the concentrations were far above the ambient atmospheric levels usually found in nature. Under such conditions leaves act as an infinite sink for NH₃. More recent controlled chamber studies, however, have shown NH₃ evolving from leaves when concentrations were nearer to those of the atmosphere. ...
DOI:
10.2134/agronj1980.00021962007200060005x

12. An Automated Sample Weighing System

Author:
N. B. McLaughlin; T. F. Townley-Smith
Source:
Agronomy journal 1980 v.72 no.4 pp. 695-697
ISSN:
0002-1962
Subject:
agronomy; automation; computers
Abstract:
... A rapid weighing system was developed in order to eliminate reading and transcription errors during the recording of weights of large numbers of plot samples. The weighing system described consists of a digital electronic scale with parallel BCD outputs, an interface (described in detail), and an IBM 029 card punch. Computer cards were prepunched with the same identification code as the labels on ...
DOI:
10.2134/agronj1980.00021962007200040032x

13. An Energy-Crop Growth Variable and Temperature Function for Predicting Corn Growth and Development: Planting to Silking

Author:
Dirceu T. Coelho; Robert F. Dale
Source:
Agronomy journal 1980 v.72 no.3 pp. 503-510
ISSN:
0002-1962
Subject:
Argiaquolls; Zea mays; acreage; agricultural management; air temperature; canopy; climate; corn; crop yield; energy crops; growth and development; heat sums; hybrids; phenology; planting; prediction; silk; solar radiation; Indiana
Abstract:
... Weather effects on crop growth, development and yield have to be quantified to interpret agronomic experiments properly and to encourage use of weather and climate information in agricultural planning and the assessment of crop yield potentials. The main objective of this research was to develop a single environmental index for use in identifying the effects of the three most important weather var ...
DOI:
10.2134/agronj1980.00021962007200030023x

14. Annual Carbohydrate Variation in Culms and Rhizomes of Smooth Cordgrass (Spartina alterniflora Loisel.)

Author:
R. W. Lytle; R. J. Hull
Source:
Agronomy journal 1980 v.72 no.6 pp. 942-946
ISSN:
0002-1962
Subject:
Spartina alterniflora; Sulfaquents; agronomy; autumn; chloroform; culms; energy balance; ethanol; perchloric acid; perennial grasses; rhizomes; salt marshes; spring; starch; sucrose; sugar content; vegetative growth; winter
Abstract:
... The productivity and stability of northeastern Atlantic tidal salt marshes depend largely upon the growth and persistence of the tall and short ecophenes of smooth cordgrass (Spartina alterniflora Loisel.). While the annual energy balance upon which perennial grass persistence depends has been studied in the tall form, no such information is available for the short form. The seasonal energy relati ...
DOI:
10.2134/agronj1980.00021962007200060019x

15. Applied N and Moisture Level Effects on Yield, Depth of Root Activity, and Nutrient Uptake by Soybeans

Author:
Bashir Al-Ithawi; E. J. Deibert; R. A. Olson
Source:
Agronomy journal 1980 v.72 no.5 pp. 827-832
ISSN:
0002-1962
Subject:
Argiudolls; Glycine max; agronomy; dry matter accumulation; field experimentation; nitrogen fertilizers; nutrient uptake; seed yield; silty clay loam soils; soil water; soybeans; water content; water use efficiency
Abstract:
... The soybean [Glycine max (L.) Merrill] has commonly been recognized as a rather non-responsive crop to fertilizer treatments compared with cereals, reasons for which are quite obscure. For studying the moisture and nutritional aspects that might be involved in this anomaly, a field experiment was conducted on Sharpsburg silty clay loam, a Typic Argiudoll, at three moisture levels, with three depth ...
DOI:
10.2134/agronj1980.00021962007200050031x

16. Assessing the Sulfur Status of Field-Grown Wheat by Plant Analysis

Author:
K. Spencer; J. R. Freney
Source:
Agronomy journal 1980 v.72 no.3 pp. 469-472
ISSN:
0002-1962
Subject:
Triticum aestivum; agronomy; ammonium nitrate; cultivars; grain yield; greenhouses; gypsum; leaves; plant analysis; plant tissues; soft white wheat; sulfates; sulfur; sulfur fertilizers; total nitrogen
Abstract:
... Diagnostic methods developed under laboratory or greenhouse conditions require field confirmation. This paper reports the relative field performance of four indexes for the diagnosis of S deficiency in wheat (Triticum aestivum L.) which were previously assessed in the greenhouse. Sulfate S (as percent total S), sulfate S concentration (as ppm dry matter), total S concentration (as ppm dry matter), ...
DOI:
10.2134/agronj1980.00021962007200030015x

17. Biochemical and Morphological Responses of Cannabis sativa L. to Postemergent Applications of Paraquat

Author:
C. B. Coffman; W. A. Gentner
Source:
Agronomy journal 1980 v.72 no.3 pp. 535-537
ISSN:
0002-1962
Subject:
Cannabis sativa; application rate; cannabidiol; greenhouse experimentation; paraquat; pesticide application; plant growth; sowing
Abstract:
... Paraquat (1,1'-dimethyl-4,4'-bipyridinium ion) has been used to control illicit fields of Cannabis sativa L. (marihuana). Little is known concerning the effects of paraquat on the growth and cannabinoid concentrations of C. sativa. Therefore, three greenhouse experiments were conducted to 1) apply paraquat postemergent to C. sativa plants under controlled conditions; 2) evaluate the morphological ...
DOI:
10.2134/agronj1980.00021962007200030029x

18. Calcium Leaching to Increase Rooting Depth in a Brazilian Savannah Oxisol

Author:
K. Dale Ritchey; Djalma M. G. Souza; Edson Lobato; Osni Correa
Source:
Agronomy journal 1980 v.72 no.1 pp. 40-44
ISSN:
0002-1962
Subject:
Oxisols; agronomy; calcium; calcium sulfate; gypsum; plant available water; plant stress; rain; root growth; soil pH; subsoil; superphosphate; Brazil
Abstract:
... Root growth in subsoils of Oxisols is often precluded because the roots of many crops are sensitive to soil acidity. This increases plant stress during dry periods when available soil water in the limed surface layers is exhausted. The low soil CEC and high rainfall in Central Brazil suggest that soluble calcium salts might leach below the plow layer and reduce soil acidity. To test this possibili ...
DOI:
10.2134/agronj1980.00021962007200010009x

19. Characteristics of the Occurrence and Some Factors Associated with Reduced Palatibility of Pearl Millet

Author:
F. M. Rouquette; T. C. Keisling; B. J. Camp; K. L. Smith
Source:
Agronomy journal 1980 v.72 no.1 pp. 173-174
ISSN:
0002-1962
Subject:
Pennisetum glaucum; alkaloids; cattle; drought; grazing; highlands; hybrids; irrigation; nitrates; palatability; pastures; rain; shredding; water stress; Texas
Abstract:
... During the prolonged drought conditions of 1978, cattle throughout the East Texas area abruptly refused to graze many fields of commercial pearl millet hybrids [Pennisetum americanum (L) K. Schum.]. This study was undertaken to characterize the occurrence of the lack of palatability, investigate some plant factors associated with reduced palatability, and verify that drought was involved in the de ...
DOI:
10.2134/agronj1980.00021962007200010036x

20. Close-Grown Tobacco: Agronomic Characteristics, Total Alkaloid, and Sugar Content

Author:
C. R. Campbell; J. F. Chaplin; W. H. Johnson; G. S. Miner
Source:
Agronomy journal 1980 v.72 no.5 pp. 773-776
ISSN:
0002-1962
Subject:
Nicotiana tabacum; agronomic traits; alkaloids; chemical analysis; cigarettes; flue-cured tobacco; harvesting; loamy sand soils; manufacturing; nitrogen; planting; reducing sugars; row spacing; sugar content
Abstract:
... The development of synthetic smoking materials has prompted researchers to consider non-conventional production methods as a means of producing a low cost, flue-cured tobacco (Nicotiana tabacum L.) material which might be used in the manufacture of cigarettes. In order to evaluate yield potential, chemical content, and physical characteristics of close-grown tobacco, plants were grown in the field ...
DOI:
10.2134/agronj1980.00021962007200050020x