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You searched for: Publication Year 1993 Remove constraint Publication Year: 1993 Source 1993 v.85 no.3 Remove constraint Source: 1993 v.85 no.3
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1. Agronomic Practices that Affect Corn Kernel Characteristics

Author:
M. Ahmadi; W. J. Wiebold; J. E. Beuerlein; D. J. Eckert; J. Schoper
Source:
Agronomy journal 1993 v.85 no.3 pp. 615-619
ISSN:
0002-1962
Subject:
Zea mays; plant density; crop yield; seeds; nitrogen content; hardness; seed quality; sowing date; grains; Ohio
Abstract:
... Agronomic practices affect corn (Zea mays L.) grain yield and may affect physical and chemical characteristics of corn kernels. These characteristics affect feed, food, and industrial uses of corn grain. Four field experiments consisting of planting date and population combinations were conducted to determine the effect of these agronomic practices on grain yield, kernel N concentration, and kerne ...
DOI:
10.2134/agronj1993.00021962008500030018x

2. Application Placement and Timing of Nitrogen Solution for No-Till Corn

Author:
J. A. Stecker; D. D. Buchholz; R. G. Hanson; N. C. Wollenhaupt; K. A. McVay
Source:
Agronomy journal 1993 v.85 no.3 pp. 645-650
ISSN:
0002-1962
Subject:
Zea mays; no-tillage; urea fertilizers; nutrient solutions; preplanting treatment; soil injection; crop yield; nutrient uptake; nitrogen; leaves; losses from soil; volatilization; application timing; application rate; grains; Missouri
Abstract:
... Fertilizing no-till corn (Zea mays L.) with urea-based N sources requires managing for N losses such as immobilization and NH₃ volatilization. In this study the interactive effects of fertilizer N application time and placement method were evaluated by applying urea ammonium nitrate (UAN) solution to no-till corn. Eight site-years of data were collected from sites in central, northeast, and northw ...
DOI:
10.2134/agronj1993.00021962008500030023x

3. Bahiagrass Canopy Size, Soil Water, and Establishment of Aeschynomene

Author:
R. S. Kalmbacher; F. G. Martin; L. C. Hammond; K. J. Boote; P. Mislevy
Source:
Agronomy journal 1993 v.85 no.3 pp. 535-540
ISSN:
0002-1962
Subject:
Aeschynomene americana; pasture plants; Paspalum notatum; sward; canopy; soil water potential; soil water content; seedlings; evapotranspiration; rain; Florida
Abstract:
... Aeschynomene americana L. is a tropical pasture legume, and in Florida, where it is usually grown with bahiagrass (Paspalum notatum Flügge), there are about 5000 ha. Limited soil water is a primary reason for stand failure of this annual. Soil water in three bahiagrass canopy sizes: small (2.2 leaf area index [LAI]), medium (4.5 LAI) and large (7.7 LAI) was measured at seeding and related to aesch ...
DOI:
10.2134/agronj1993.00021962008500030003x

4. Carbon and Phosphorus Losses from Decomposing Crop Residues in No-Till and Conventional Till Agroecosystems

Author:
Marc Buchanan; Larry D. King
Source:
Agronomy journal 1993 v.85 no.3 pp. 631-638
ISSN:
0002-1962
Subject:
crop residue management; no-tillage; carbon; phosphorus; roots; biogeochemical cycles; shoots; losses from soil; Triticum aestivum; degradation; leaves; mineralization; Zea mays; Glycine max; winter; Trifolium incarnatum; conventional tillage; crop residues; grains; lignin; nitrogen; cover crops; chemical constituents of plants; North Carolina
Abstract:
... An increased knowledge of crop residue decomposition characteristics is a critical component for nutrient cycling studies in agroecosystems. Carbon and P losses from shoot residues of maize (Zea mays L.), wheat [Triticum estivum (L.), emend. Thell], soybean [Glycine max (L.) Merr.], and shoot and root residues of crimson clover (Trifolium incarnatum L.) were compared in no-till and conventional ti ...
DOI:
10.2134/agronj1993.00021962008500030021x

5. Creeping Bentgrass Rooting as Influenced by Dithiopyr

Author:
P. H. Dernoeden; N. E. Christians; J. M. Krouse; R. G. Roe
Source:
Agronomy journal 1993 v.85 no.3 pp. 560-563
ISSN:
0002-1962
Subject:
Agrostis stolonifera var. palustris; lawns and turf; pyridine herbicides; weed control; chemical control; phytotoxicity; rooting; leaves; crop damage; roots; weight; chlorthal-dimethyl; bensulide; oxadiazon; application rate; application timing; discoloration; Iowa; Maryland
Abstract:
... Dithiopyr [3,5-pyridinedicarbothioic acid, 2-(difluoromethyl)-4(2-methylpropyl)-6-trifluoromethyl)S,S-dimethyl ester] is a new herbicide, but its foliar safety and potential rooting effects need to be documented before its use on creeping bentgrass (Agrostis palustris Huds.) can be recommended. Field studies were conducted at five separate sites in Iowa and in Maryland, where creeping bentgrass wa ...
DOI:
10.2134/agronj1993.00021962008500030008x

6. Crop Performance Trials under Irrigated and Dryland Conditions

Author:
Daryl Bowman; Paul Raymer; Don Dombeck
Source:
Agronomy journal 1993 v.85 no.3 pp. 610-614
ISSN:
0002-1962
Subject:
Zea mays; Glycine max; irrigated conditions; dry environmental conditions; cultivars; hybrids; water stress; genotype-environment interaction; genetic variation; variety trials; crop yield; North Carolina; Georgia
Abstract:
... Corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] performance trials are sometimes conducted under both irrigated and dryland conditions in the southeastern USA. It is not known whether irrigated trials are better trials statistically or if irrigation causes relative rank changes in hybrid or cultivar performance. To answer these questions, corn data were examined from four different environ ...
DOI:
10.2134/agronj1993.00021962008500030017x

7. Development of Double-Crop Soybean under Different Soil Water Regimes

Author:
R. C. Pearce; L. J. Grabau; J. H. Grove; H. Lin
Source:
Agronomy journal 1993 v.85 no.3 pp. 576-583
ISSN:
0002-1962
Subject:
Glycine max; double cropping; Triticum aestivum; soil water content; crop yield; seeds; rain; dry environmental conditions; water stress; drought; sowing date; Kentucky
Abstract:
... Double-crop soybean [Glycine max (L.) Merr.] comprises nearly one-third of the total soybean hectarage in the southeasteirn USA. This study was initiated to investigate the water relations of soybean following winter wheat [Triticum aestivum (L.) emend. Thcll], with emphasis on the role of stored soil water. A treatment scheme was devised in which wheat was killed at heading, mid-grain fill, and m ...
DOI:
10.2134/agronj1993.00021962008500030011x

8. ENWATBAL.BAS: a Mechanistic Evapotranspiration Model Written in Compiled Basic

Author:
S. R. Evett; R. J. Lascano
Source:
Agronomy journal 1993 v.85 no.3 pp. 763-772
ISSN:
0002-1962
Subject:
simulation models; evapotranspiration; soil temperature; soil water content; data analysis; statistical analysis; computer software; microcomputers; prediction
Abstract:
... ENWATBAL, a mechanistic energy, water balance model originally written in the Continuous System Modeling Program (CSMP) simulation language, was largely incompatible with personal computers (PCs). ENWATBAL.BAS was developed to extend the model application to PCs using BASIC, which is widely available. BASIC functions or subprograms were provided to emulate CSMP language commands including integrat ...
Handle:
10113/718
DOI:
10.2134/agronj1993.00021962008500030044x

9. Evaluation of Statistical Methods for Determining Differences between Samples from Lognormal Populations

Author:
T. B. Parkin
Source:
Agronomy journal 1993 v.85 no.3 pp. 747-753
ISSN:
0002-1962
Subject:
analysis of variance; soil properties; probability analysis; data analysis; crops
Abstract:
... Soil variables often exhibit frequency distributions that are positively skewed. When this situation exists, the assumption of normality associated with analysis-of-variance procedures is violated, and two common recommendations are given: (i) perform a normalizing transformation, or (ii) apply nonparametric statistical methods. Information regarding the relative efficacy of these two procedures w ...
Handle:
10113/49171
DOI:
10.2134/agronj1993.00021962008500030041x

10. Evapotranspiration and Yield of Beans as Affected by Mulch and Irrigation

Author:
L. C. G. Barros; R. J. Hanks
Source:
Agronomy journal 1993 v.85 no.3 pp. 692-697
ISSN:
0002-1962
Subject:
Phaseolus vulgaris; mulching; wheat straw; irrigated conditions; sprinkler irrigation; crop yield; seeds; evapotranspiration; water use efficiency; transpiration; evaporation; application rate; Utah
Abstract:
... Mulch (crop residue) has been reported to increase soil water storage and crop yield, and to reduce soil water stress under some conditions. However, few studies have had irrigations, and thus evapotranspiration (ET), as a variable where soil water was controlled. Therefore, a study was conducted to evaluate the effect of mulch on ET, bean yield (Phaseolus vulgaris L.), and water use efficiency (W ...
DOI:
10.2134/agronj1993.00021962008500030032x

11. Forage Quality, Mineral Constituents, and Performance of Beef Yearlings Grazing Two Crested Wheatgrasses

Author:
K. P. Vogel; B. C. Gabrielsen; J. K. Ward; B. E. Anderson; H. F. Mayland; R. A. Masters
Source:
Agronomy journal 1993 v.85 no.3 pp. 584-590
ISSN:
0002-1962
Subject:
cultivars; crop quality; blood serum; grazing; beef cattle; Agropyron desertorum; spring; liveweight gain; steers; nutritive value; grass tetany; magnesium; Agropyron cristatum; Nebraska
Abstract:
... In the central Great Plains, crested wheatgrasses [Agropyron cristatum (L.) Gaetner and A. desertorium (Fischer ex Link) Schultes] are best utilized for early spring and late fall grazing. The principal objective of this study was to determine if beef (Bos taurus L.) yearlings grazing ‘Ruff’ (A. cristatum) during the spring grazing season had higher average daily gains and gains per hectare than c ...
Handle:
10113/15650
DOI:
10.2134/agronj1993.00021962008500030012x

12. Forage Yield, Quality, Compatibility, and Persistence of Warm-Season Grass—Legume Mixtures

Author:
G. L. Posler; A. W. Lenssen; G. L. Fine
Source:
Agronomy journal 1993 v.85 no.3 pp. 554-560
ISSN:
0002-1962
Subject:
Panicum virgatum; Lespedeza; Bouteloua curtipendula; crop quality; in vitro digestibility; Desmanthus illinoensis; nutritive value; Amorpha canescens; crop yield; Astragalus cicer; Dalea purpurea; Sorghastrum nutans; Kansas
Abstract:
... Development of compatible, persistent, warm-season grass-legume mixtures could increase forage yield and quality during summer months. We established a trial to determine forage yield, quality, species compatibility, and persistence of binary mixtures of warm-season grasses with selected legumes, five of which are native to the central USA. Grass entries were switchgrass (Panicum virgatum L.), sid ...
DOI:
10.2134/agronj1993.00021962008500030007x

13. Growth, Boll Opening Rate, and Fiber Properties of Narrow-Row Cotton

Author:
James J. Heitholt; William T. Pettigrew; William R. Meredith
Source:
Agronomy journal 1993 v.85 no.3 pp. 590-594
ISSN:
0002-1962
Subject:
isogenic lines; lint cotton; seeds; Gossypium hirsutum; row spacing; early development; dry matter accumulation; crop yield; plant morphology; genotype; fiber quality; bolls; leaves; vegetative growth; Mississippi
Abstract:
... Row spacing has the potential to affect agronomic traits of upland cotton (Gossypium hirsutum L.). Although narrow-rows can pose numerous management challenges (e.g., cultivation and harvesting), the benefits of narrow-rows may justify their use. Unfortunately, the extent and consistency of cotton's response to narrow-rows is variable, which makes management decisions more difficult. The objective ...
DOI:
10.2134/agronj1993.00021962008500030013x

14. Inadequacy of the Liebig Limiting-Factor Paradigm for Explaining Varying Crop Yields

Author:
Thomas R. Sinclair; Wayne I. Park
Source:
Agronomy journal 1993 v.85 no.3 pp. 742-746
ISSN:
0002-1962
Subject:
crops; growth models; prediction; plant development; crop yield; equations; mathematical models
Abstract:
... Historically, the limiting-factor paradigm has been used to describe how crop yields may be constrained by the individual input resources required by plants. The limiting-factor paradigm proposes that plant growth is constrained only by a single resource whose availability is so low that it solely inhibits greater growth or growth rates. However, this paradigm ignores the great flexibility of plan ...
DOI:
10.2134/agronj1993.00021962008500030040x

15. An Inexpensive Thermocouple Multiplexing Device

Author:
C. K. Kvien; J. E. Hook; S. J. Thomson; M. C. Smith
Source:
Agronomy journal 1993 v.85 no.3 pp. 773-776
ISSN:
0002-1962
Subject:
research equipment; thermocouples; monitoring; microcomputers; data collection; computer techniques
Abstract:
... The expense of monitoring large numbers of thermocouples has constrained many research and development projects. We developed an inexpensive multiplexing device which allows 640 or more thermocouples to be accessed from a microcomputer. The multiplexing unit is connected to a microcomputer expansion box equipped with a 16-channel digital input/output (I/O) board and a preamp connected to an analog ...
DOI:
10.2134/agronj1993.00021962008500030045x

16. Leaf Expansion in Field-Grown Sunflower in Response to Soil and Leaf Water Status

Author:
V. O. Sadras; F. J. Villalobos; E. Fereres
Source:
Agronomy journal 1993 v.85 no.3 pp. 564-570
ISSN:
0002-1962
Subject:
Helianthus annuus; leaf area; leaves; leaf water potential; soil water content; dry environmental conditions; root systems; irrigated conditions; spring; summer; water stress; Spain
Abstract:
... Leaf responses to soil water deficits in controlled environaments may be mediated by nonhydraulic root signals (RS). The aim uf this study was to evaluate in the field the effects of RS and leaf water potential (Ψ¹) on leaf expansion rate (LER) of sunflower (Helianihus annuus L.). Two experiments were performed on a deep sandy-loam soil (Typic Xerofluvent) in a Mediterranean environment under spri ...
DOI:
10.2134/agronj1993.00021962008500030009x

17. Light Transmittance, Soil Temperature, and Soil Moisture under Residue of Hairy Vetch and Rye

Author:
J. R. Teasdale; C. L. Mohler
Source:
Agronomy journal 1993 v.85 no.3 pp. 673-680
ISSN:
0002-1962
Subject:
Secale cereale; Vicia villosa; cover crops; crop residues; biomass; weeds; seed germination; soil temperature; soil water content; cultural control; weed control; crop residue management; Maryland; New York
Abstract:
... Cover crop residue on the surface of soils in no-tillage systems can suppress weed emergence and growth. Although allelopathy often is invoked to explain weed suppression by residue, physical alterations of the seed environment could be important as well. This experiment was conducted to determine the light, temperature, and moisture conditions under cover crop residue. Hairy vetch (Vicia villosa ...
DOI:
10.2134/agronj1993.00021962008500030029x

18. Logistic Response of Bermudagrass and Bunchgrass Cultivars to Applied Nitrogen

Author:
A. R. Overman; M. A. Sanderson; R. M. Jones
Source:
Agronomy journal 1993 v.85 no.3 pp. 541-545
ISSN:
0002-1962
Subject:
interspecific variation; cultivars; mathematical models; forage crops; Panicum coloratum; application rate; soil water content; Cynodon dactylon; arid zones; dry matter accumulation; crop yield; rain; growth models; Eragrostis curvula; Cenchrus ciliaris; nitrogen fertilizers; Texas
Abstract:
... Models provide a quantitative means to evaluate yield response of forage grasses to applied N and water availability. The objective of this analysis was to estimate model parameters (A, b, c) for bermu. dagrasses and bunchgrasses grown at the same location and during the same time period. The logistic equation was used to relate annual dry matter production to applied N for three bermudagrasses [C ...
DOI:
10.2134/agronj1993.00021962008500030004x

19. Management and Environment Effects on Dry Matter Yields of Three Brassica Species

Author:
M. Hagemann Wiedenhoeft
Source:
Agronomy journal 1993 v.85 no.3 pp. 549-553
ISSN:
0002-1962
Subject:
harvest date; interspecific variation; Brassica rapa subsp. pekinensis; hybrids; sowing date; soil water content; grazing; air temperature; dry matter accumulation; regrowth; forage; crop yield; Brassica napus; Brassica rapa subsp. oleifera; cold; Maine
Abstract:
... Brassica crops have potential use as a forage during summer, fall, and early winter months. The influence of planting date and harvest date on the initial and regrowth herbage yields for three Brassica species: rape (B. napus L., ‘Winfred’ in 1987 and ‘Emerald’ in 1988 and 1989), turnip (B. rapa L., ‘Purple Top’), and a turnip hybrid (B. rapa × B. pekinensis L., ‘Tyfon’) were investigated. The spe ...
DOI:
10.2134/agronj1993.00021962008500030006x

20. Model of Integrated Effects of Boron, Inert Salt, and Water Flow on Crop Yield

Author:
U. Shani; R. J. Hanks
Source:
Agronomy journal 1993 v.85 no.3 pp. 713-717
ISSN:
0002-1962
Subject:
Zea mays; simulation models; Hordeum vulgare; phytotoxicity; equations; boron; leaching; soil salinity; growth models; water flow; soil water; crop yield; soil salts; Utah
Abstract:
... High boron concentration in the soil causes yield reduction. Recently, a piecewise linear response curve was applied to describe yield response to B in near steady-state conditions. However, application of similar curves to field situations where water, B, and other ion contents are transient and nonhomogeneous is limited. The objective of this study was to develop a model for simulation of the in ...
DOI:
10.2134/agronj1993.00021962008500030036x

21. Modeling Pepper Seedling Growth and Nutrient Uptake as a Function of Cultural Conditions

Author:
A. Bar-Tal; B. Bar-Yosef; U. Kafkafi
Source:
Agronomy journal 1993 v.85 no.3 pp. 718-724
ISSN:
0002-1962
Subject:
simulation models; seedling growth; Capsicum annuum; nitrogen; seedlings; irrigation; fertilizers; equations; nutrient uptake; plant density; growth models; growing media; nutrient solutions; seedling production; phosphorus; water uptake
Abstract:
... A mechanistic model was developed to describe pepper seedling growth, and water, N, and P uptake as a function of N and P concentrations in the irrigation solution, growth medium volume per plant, planting density, and growth substrate characteristics. Such a model will help optimize irrigation and fertilization of transplants and elucidate some of the mechanisms involved in seedling production. T ...
DOI:
10.2134/agronj1993.00021962008500030037x

22. Nitrification Inhibitor Influences on Potato

Author:
H. W. Martin; D. A. Graetz; S. J. Locascio; D. R. Hensel
Source:
Agronomy journal 1993 v.85 no.3 pp. 651-655
ISSN:
0002-1962
Subject:
Solanum tuberosum; nitrification; nitrification inhibitors; nitrogen fertilizers; losses from soil; loss prevention; dicyandiamide; nitrapyrin; crop yield; tubers; crop quality; specific gravity; nitrogen; leaves; sandy soils; chemical constituents of plants; Florida
Abstract:
... Nitrification inhibitors may reduce loss of fertilizer N from the root zone by reducing leaching and denitrification. This reduced N loss should be reflected in increased crop yields. These studies were conducted to determine if potato yield, specific gravity, or leaf N at flowering would be increased by use of nitrification inhibitors. Nitrification inhibitors dicyandiamide (DCD) and 2-chloro-6-( ...
DOI:
10.2134/agronj1993.00021962008500030024x

23. Nitrogen Availability from Surface-Applied and Soil-Incorporated Crop Residues

Author:
S. J. Smith; A. N. Sharpley
Source:
Agronomy journal 1993 v.85 no.3 pp. 776-778
ISSN:
0002-1962
Subject:
Medicago sativa; Sorghum bicolor; Triticum aestivum; crop residues; stable isotopes; isotope labeling; nitrogen; nutrient availability; crop residue management; Oklahoma
Abstract:
... Management systems which maintain crop residues on the soil surface have prompted a need for more detailed information regarding crop residue N availability. Such information is needed from both agronomic and environmental standpoints. Our study examined the placement effects of ¹⁵N tagged alfalfa (Medicago sativa L.), sorghum [Sorghum bicolor (L.) Moench], and wheat (Triticum aestivum L.) residue ...
Handle:
10113/19441
DOI:
10.2134/agronj1993.00021962008500030046x

24. No-Till Corn Production as Affected by Mulch, Potassium Placement, and Soil Exchangeable Potassium

Author:
H. Yibirin; J. W. Johnson; D. J. Eckert
Source:
Agronomy journal 1993 v.85 no.3 pp. 639-644
ISSN:
0002-1962
Subject:
Zea mays; no-tillage; potassium fertilizers; mulches; exchangeable potassium; crop yield; leaves; nutrient uptake; roots; spatial distribution; corn stover; application rate; grains; chemical constituents of plants; band placement; Ohio
Abstract:
... Optimizing the yield of no-till corn (Zea mays L.) requires an understanding of corn response to K fertilization practices in no-tillage systems. This study was conducted to determine the effects of mulch rate, K-fertilizer placement method, and soil exchangeable K (SEK) concentration on corn grain yield, ear leaf K concentration (ELKC), and root SEK distribution in a no-tillage system. There were ...
DOI:
10.2134/agronj1993.00021962008500030022x

25. Plant Growth Regulator Effects on Growth and Forage Quality of Tall Fescue

Author:
J. H. Reynolds; W. A. Krueger; C. L. Walker; J. C. Waller
Source:
Agronomy journal 1993 v.85 no.3 pp. 545-548
ISSN:
0002-1962
Subject:
mefluidide; crop quality; Festuca arundinacea; in vitro digestibility; application timing; autumn; fiber content; haloxyfop; spring; forage; crude protein; sexual reproduction; growth retardation; sethoxydim; glyphosate; crop yield; chemical control; heading; Tennessee
Abstract:
... Forage quality of tall fescue (Festuca arundinacea Schreb.) is low in the spring after heading. Plant growth regulators (PGRs) have been shown to improve forage quality through inhibition of seedhead development. The objective of this study was to compare the effect of fall or spring application of six PGRs on heading, yield, and forage quality of tall fescue. The soil was an Etowah silt loam (fin ...
DOI:
10.2134/agronj1993.00021962008500030005x

26. Plant Yields and Fodder Quality Related Characteristics of Millet-Stylo Intercropping Systems in the Sahel

Author:
C. N. Kouamé; J. M. Powell; C. A. Renard; K. H. Quesenberry
Source:
Agronomy journal 1993 v.85 no.3 pp. 601-605
ISSN:
0002-1962
Subject:
crop quality; nutritive value; Pennisetum glaucum; dry matter accumulation; Stylosanthes hamata; crop yield; crude protein; grains; Sahel; intercropping; Niger
Abstract:
... The integration of forage legumes into the low-input, cereal-based farming system of the Sahel may be the key to sustaining soil, crop, and livestock production. The objectives of this study were to evaluate the effects of intercropping the forage legumes Stylosanthes fruticosa (Retz.) Alston or S. hamata (L.) Taub. with millet [Pennisetum glaucum (L.) R. Br.J on grain yield, fodder yield, and cru ...
DOI:
10.2134/agronj1993.00021962008500030015x

27. Post-Anthesis Nitrogen Loss from Corn

Author:
D. D. Francis; J. S. Schepers; M. F. Vigil
Source:
Agronomy journal 1993 v.85 no.3 pp. 659-663
ISSN:
0002-1962
Subject:
Zea mays; flowering; irrigated conditions; nitrogen fertilizers; nitrogen; nutrient uptake; leaves; stems; volatilization; losses from soil; leaching; denitrification; application rate; grains
Abstract:
... Published research has shown relatively large amounts of NH₃ being lost from aboveground vegetation during grain development for various grain crops For corn (Zea mays L.), maximum net N accumulation usually occurs during early reproductive development (R1-R3) and a subsequent decline is often observed. Two recently completed N fertilizer recovery studies on irrigated corn utilizing isotopic techn ...
Handle:
10113/17158
DOI:
10.2134/agronj1993.00021962008500030026x

28. Predicting Grain Sorghum Canopy Structure for Soil Erosion Modeling

Author:
D. V. Armbrust; J. D. Bilbro
Source:
Agronomy journal 1993 v.85 no.3 pp. 664-668
ISSN:
0002-1962
Subject:
Sorghum bicolor; canopy; plant morphology; prediction; mathematical models; equations; wind erosion; water erosion
Abstract:
... Development of modern water and wind erosion prediction technology requires information on the canopy structure of various plant species to accurately predict the canopy effect on the falling raindrop or the erosive force of the wind. The objective of this study was to develop equations to predict grain sorghum [Sorghum bicolor (L.) Moench] canopy structure characteristics. Groin sorghum plants we ...
DOI:
10.2134/agronj1993.00021962008500030027x

29. Radiation-Use Efficiency among Grain Sorghum Cultivars and Plant Densities

Author:
W. D. Rosenthal; T. J. Gerik; L. J. Wade
Source:
Agronomy journal 1993 v.85 no.3 pp. 703-705
ISSN:
0002-1962
Subject:
Sorghum bicolor; cultivars; solar radiation; plant density; growth models; dry matter accumulation; leaf area index; photosynthesis; mathematical models; Texas
Abstract:
... Radiation-use efficiency (RUE, g MJ−¹) has often been used in many crop model equations to estimate total biomass and yield based on cumulative absorbed photosynthetically active radiation. Management practice effects on radiation-use efficiency have not been well documented for grain sorghum [Sorghum bicolor (L.) Moench]. A field study was conducted near Temple, TX to determine plant density and ...
DOI:
10.2134/agronj1993.00021962008500030034x

30. Residual Effects of Soil Profile Modification on Water Infiltration, Bulk Density, and Wheat Yield

Author:
Paul W. Unger
Source:
Agronomy journal 1993 v.85 no.3 pp. 656-659
ISSN:
0002-1962
Subject:
Triticum aestivum; crop yield; site preparation; soil texture; clay loam soils; soil profiles; soil density; bulk density; soil water content; water use efficiency; residual effects; preplanting treatment; grains; Texas
Abstract:
... Fine-textured soils of the Southern High Plains, of which Pullman (fine, mixed, thermic Torrertic Paleustolls) is the dominant series,/ have inherently low water infiltration rates. Pullman soils have a moderately permeable surface horizon overlying and slowly-permeable Bt horizon, which limits deep water penetration, thus hampering water conservation efforts and reducing water-use efficiencies Ib ...
DOI:
10.2134/agronj1993.00021962008500030025x

31. Response of Cotton to Varying COz, Irrigation, and Nitrogen: Yield and Growth

Author:
B. A. Kimball; J. R. Mauney
Source:
Agronomy journal 1993 v.85 no.3 pp. 706-712
ISSN:
0002-1962
Subject:
source-sink relationships; carbon dioxide; lint cotton; seeds; Gossypium hirsutum; dry environmental conditions; irrigated conditions; dry matter accumulation; water stress; harvest index; photosynthesis; root shoot ratio; nitrogen fertilizers; Arizona
Abstract:
... The CO₂ concentration of the atmosphere is increasing and is expected to double sometime near the middle of the next century. To determine the effects of such a CO₂ increase on cotton (Gossypium hirsutum L.) growth and productivity, a series of experiments from 1983 through 1987 were conducted with open-top CO₂-enriched field chambers at ample as well as limiting levels of water and N at Phoenix, ...
Handle:
10113/50192
DOI:
10.2134/agronj1993.00021962008500030035x

32. Resumption of Water Uptake by Sorghum after Water Stress

Author:
X. Xu; W. L. Bland
Source:
Agronomy journal 1993 v.85 no.3 pp. 697-702
ISSN:
0002-1962
Subject:
Sorghum bicolor; water stress; duration; root systems; water uptake; transpiration; leaf water potential; soil water content; drought tolerance; dry environmental conditions; root shoot ratio; Texas
Abstract:
... Exposure of roots to dry soil may reduce their ability to absorb water when the soil is rewet. We sought to quantify the effects of the duration of exposure to dry soil and the availability of water in deeper soil layers on resumption of water uptake by roots of Sorghum bicolor (L.) Moench following rewetting of the soil. Plants were grown in a greenhouse in pots, half of which were fitted with a ...
DOI:
10.2134/agronj1993.00021962008500030033x

33. SCALES: a computer program to convert among three developmental stage scales for wheat

Author:
Harrell, D.M.; Wilhelm, W.W.; McMaster, G.S.
Source:
Agronomy journal 1993 v.85 no.3 pp. 758-763
ISSN:
0002-1962
Subject:
plant development; simulation models; rating scales; phenology; data analysis; Triticum aestivum; computer software
Abstract:
... The Haun, Feekes, and Zadoks-Chang-Konzak developmental stage scales are often used to report phenological information for wheat (Triticum aestivum L.) development. Agronomists familiar with one of these scales may have only a passing acquaintance with developmental scales other than the one they consider most appropriate for their purposes. This makes review and interpretation of the literature m ...
Handle:
10113/16641
DOI:
10.2134/agronj1993.00021962008500030043x

34. Simultaneous Selection for Yield and Stability in Crop Performance Trials: Consequences for Growers

Author:
Manjit S. Kang
Source:
Agronomy journal 1993 v.85 no.3 pp. 754-757
ISSN:
0002-1962
Subject:
variety trials; Zea mays; probability analysis; crop yield; genotype-environment interaction; data analysis
Abstract:
... Utilization of genotype × environment (GE) interaction encountered in crop performance trials is an important issue among plant breeders and agronomists. Practical integration of yield and stability of performance has not been achieved. The purposes of this paper are (i) to examine consequences to growers when researchers commit Type I (rejecting the null hypothesis or Hₒ when it is true) and Type ...
DOI:
10.2134/agronj1993.00021962008500030042x

35. Soil Temperature, Soil Water, and No-Till Corn Development Following In-Row Residue Removal

Author:
M.-C. Fortin
Source:
Agronomy journal 1993 v.85 no.3 pp. 571-576
ISSN:
0002-1962
Subject:
height; plant characteristics; Zea mays; no-tillage; crop residues; dry environmental conditions; soil temperature; soil water content; vegetative growth; sexual reproduction; heading; crop yield; grains; conventional tillage; crop residue management; arid zones; Ontario
Abstract:
... In northern areas where corn (Zea mays L.) is grown, no-till plants develop more slowly and, consequently, could be more susceptible to soil water limitations than plants under conventional tillage. This study was conducted to determine if removing in-row residues by pushing them into the interrow can solve problems related to no-till corn development in droughty soils. Residues were removed to pr ...
DOI:
10.2134/agronj1993.00021962008500030010x

36. Sub-Root Zone Layering: Effects on Water Retention in Sports Turf Soil Profiles

Author:
D. H. Taylor; S. D. Nelson; C. F. Williams
Source:
Agronomy journal 1993 v.85 no.3 pp. 626-630
ISSN:
0002-1962
Subject:
gravel; soil water content; athletic fields; lawns and turf; mixtures; soil texture; soil profiles; soil water retention; drainage; sand
Abstract:
... Sports turf areas are often constructed by placing a root zone soil mixture over coarse-textured layers such as sand or gravel. The objective of this research was to determine the degree to which drainage from and water retention in soil mixtures were affected I~.y properties of the underlying layers. In a laboratory experiment, soil water matric potential energies (Ψₘ) and mass water contents (θₘ ...
DOI:
10.2134/agronj1993.00021962008500030020x

37. Subsurface Compaction Effects on Tillering and Nitrogen Accumulation in Wheat

Author:
M. Oussible; R. R. Allmaras; R. D. Wynch; R. K. Crookston
Source:
Agronomy journal 1993 v.85 no.3 pp. 619-625
ISSN:
0002-1962
Subject:
nitrogen content; stems; tillering; nutrient uptake; crop yield; Triticum aestivum; soil compaction; nitrogen fertilizers; Morocco; Minnesota
Abstract:
... Compaction in the 0.05- to 0.30-m depth may limit tillering and N accumulation in wheat (Triticum aestivum L.); these effects may be yield reducing. Before imposing compaction treatments in a field study in Minnesota, perforated small-diameter tubing was buried in a Waukegan silt loam (sandy skeletal, mixed, mesic Typic Hapludoll) at a depth of 0.2 m in all plots. Compacted plots each received fou ...
DOI:
10.2134/agronj1993.00021962008500030019x

38. A Sunflower Simulation Model: I. Model Development

Author:
Scott C. Chapman; Graeme L. Hammer; Holger Meinke
Source:
Agronomy journal 1993 v.85 no.3 pp. 725-735
ISSN:
0002-1962
Subject:
simulation models; Helianthus annuus; plant development; dry environmental conditions; phenology; dry matter accumulation; growth models; crop yield; decision making; prediction
Abstract:
... In dryland farming systems, opportunities to improve sunflower (Helianthus annuus L.) yields are mostly associated with management decisions made at planting. Dynamic crop simulation models can assist in making such decisions. This study reports the structure of QSUN, a simple and mechanistic crop model for sunflower, and how it accounts for the dynamic interaction of the crop with the soil and ae ...
DOI:
10.2134/agronj1993.00021962008500030038x

39. A Sunflower Simulation Model: II. Simulating Production Risks in a Variable Sub-Tropical Environment

Author:
Holger Meinke; Graeme L. Hammer; Scott C. Chapman
Source:
Agronomy journal 1993 v.85 no.3 pp. 735-742
ISSN:
0002-1962
Subject:
simulation models; Helianthus annuus; sowing date; tropics; subtropics; growth models; crop yield; seasonal variation; climatic factors; decision making; prediction; Queensland
Abstract:
... In highly variable environments, farmers require quantitative information on production risk to make well informed farming decisions. In many cases this can only be achieved through simulation studies. Thus, the dynamic sunflower (Helianthus annuus L) model QSUN was used, in conjunction with long-term climate records, to quantify the impact of climatic variability on production. Simulation results ...
DOI:
10.2134/agronj1993.00021962008500030039x

40. Sward Height and Vertical Morphological Differentiation Determine Cattle Bite Dimensions

Author:
Enrique R. Flores; Emilio A. Laca; Thomas C. Griggs; Montague W. Demment
Source:
Agronomy journal 1993 v.85 no.3 pp. 527-532
ISSN:
0002-1962
Subject:
height; plant characteristics; sward; Paspalum dilatatum; leaves; length; steers; biting rates; weight; depth; area; plant morphology; California
Abstract:
... To identify and quantify the influence of sward structure on the intake of grazing animals requires an understanding of sward-animal interactions at the bite level. We tested the hypothesis that bite dimensions on vertically heterogeneous swards are determined by structural characteristics of the top leaf stratum, independent of those of a bottom layer of pseudostem or stem. Dallisgrass (Paspalum ...
DOI:
10.2134/agronj1993.00021962008500030001x

41. Temperature Effects on Pima Cotton Leaf Growth

Author:
K. R. Reddy; H. F. Hodges; J. M. McKinion
Source:
Agronomy journal 1993 v.85 no.3 pp. 681-686
ISSN:
0002-1962
Subject:
Gossypium barbadense; phenology; heat sums; air temperature; leaves; dry matter accumulation
Abstract:
... Temperature is a primary environmental factor affecting cotton growth. Information on temperature effects on Pima cotton (Gossypium barbadense L.) growth is limited. The objective of this paper is to provide quantitative estimates of temperature effects on leaf emergence rates, the duration of leaf expansion, and rate of expansion. Pima cotton plants were grown from seed in naturally lit controlle ...
DOI:
10.2134/agronj1993.00021962008500030030x

42. Water Use, Intercepted Radiation, and Soil Temperature of Skip-Row and Equidistant-Row Barley

Author:
B. S. Sharratt
Source:
Agronomy journal 1993 v.85 no.3 pp. 686-691
ISSN:
0002-1962
Subject:
Hordeum vulgare; row spacing; soil temperature; subarctic soils; microclimate; water use efficiency; solar radiation; nitrogen fertilizers; transpiration; canopy; leaf area index; light; band placement; Alaska; Arctic region
Abstract:
... Cropping systems are sought in the subarctic that improve the plant growing environment for sustained and diversified production of crops. This study assessed whether microclimate and water use of barley (Hordeum vulgare L.) could be altered in the subarctic by crop row configuration and fertilizer placement. Treatments established at Fairbanks, AK, included equidistant-row planting (0.18-m equidi ...
DOI:
10.2134/agronj1993.00021962008500030031x

43. Within-Season Calibration of Modeled Wheat Growth Using Remote Sensing and Field Sampling

Author:
Stephan J. Maas
Source:
Agronomy journal 1993 v.85 no.3 pp. 669-672
ISSN:
0002-1962
Subject:
Triticum aestivum; growth models; phenology; simulation models; sampling; remote sensing; leaf area index; crop yield; calibration
Abstract:
... Within-season calibration using observations of growth and phenology provides an objective means for crop simulation models to be self-correcting. Estimating crop growth and phenology for a large number of fields by traditional ground-based sampling methods can be undesirably time-consuming. Certain aspects of crop growth can be estimated more quickly for a large number of fields using remote sens ...
DOI:
10.2134/agronj1993.00021962008500030028x

44. Yield Components of Five Kenaf Cultivars

Author:
Charles L. Weber
Source:
Agronomy journal 1993 v.85 no.3 pp. 533-535
ISSN:
0002-1962
Subject:
cultivars; kenaf; stems; genetic variation; plant characteristics; height; plant density; yield components; Hibiscus cannabinus; bark; leaves; Oklahoma
Abstract:
... As the USA approaches commercial production of kenaf (Hibiscus cannabinus L.) as an alternative fiber source for paper pulp and other uses, additional information is needed concerning the relationship among kenaf yield components. Kenaf yield components can be important parameters in the selection of the cultivars best suited for specific uses, and in maximizing the production and processing effic ...
DOI:
10.2134/agronj1993.00021962008500030002x

45. Yield Contribution of Apical and Subapical Ears in Prolific and Nonprolific Corn

Author:
R. P. Durieux; E. J. Kamprath; R. H. Moll
Source:
Agronomy journal 1993 v.85 no.3 pp. 606-610
ISSN:
0002-1962
Subject:
weight; Zea mays; hybrids; corn ears; yield components; grains; application rate; nitrogen fertilizers; North Carolina
Abstract:
... Previous studies have demonstrated higher corn (Zea mays L.) yield potential for prolific corn hybrids (more than one ear) compared nonprolific hybrids (one ear). However, little is known about the relative contribution of the second ear to total yield at various N levels. This study compared yield responses to N rates of 56, 140, and 224 kg N ha⁻¹ of prolific Hybrids A (1202 × Mo17) and B (1117 × ...
DOI:
10.2134/agronj1993.00021962008500030016x

46. Yield Responses of Alfalfa to Simulated Alfalfa Weevil Injury and Development of Economic Injury Levels

Author:
Robert K. D. Peterson; Stephen D. Danielson; Leon G. Higley
Source:
Agronomy journal 1993 v.85 no.3 pp. 595-601
ISSN:
0002-1962
Subject:
Medicago sativa; Hypera postica; crop damage; defoliation; regrowth; dry matter accumulation; crop yield; leaves; stems; economic threshold; Nebraska
Abstract:
... Although the alfalfa weevil Hypera postica (Gyilenhal)] is an important alfalfa (Medicago sativa L.) pest, relatively little is known about how defoliation at specific plant developmental stages affects yield. This study was conducted to characterize yield responses of alfalfa to simulated alfalfa weevil injury when injury was initiated at the early bud stage of the first growth cycle and to devel ...
DOI:
10.2134/agronj1993.00021962008500030014x