bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microcomputer Simulation of Expected Gains from Eight Methods of Intrapopulation Recurrent Selection
Authors: Coors J. G. , Staub J. E. , Senalik D. , Rinehart C. A. 
Published: July 2010

AbstractAn interactive microcomputer program was developed to provide plant breeders and graduate students in quantitative genetics the opportunity to devise selection strategies and review expected gains for eight intrapopulation selection methods. Selection methods include uniparental and biparental mass selection, three forms of half‐sib selection, full‐sib selection, and S1 and S2 selection. Users provide estimates of genetic and environmental components of variance, selection intensities, and an array of possible experimental designs including number of environments, number of replicates within environments, and plot size. Expected gains can be expressed as either gain cycle−1, gain year−1, or gain season−1. Help screens are included that explain selection methods and the calculation of expected gains. The program is designed so the user can easily move within it, reenter values for individual variables, and rapidly redisplay results.
Water Use Efficiency and Dry Matter Distribution in Nitrogen‐ and Water‐Stressed Winter Wheat
Authors: Heitholt J. J. 
Published: July 2010

AbstractWater use efficiency (WUE) and the distribution of dry matter to the roots in wheat (Triticum aestivum L.) are potential selection criteria for improving yield under water stress. The objectives of this research were (i) to compare methods of measuring WUE, and (ii) to determine the distribution of dry matter between shoots and roots in water‐ and N‐stressed wheat. Winter wheat was grown in a potting mixture for 6 wk in growth chambers with varying levels of N and water. Nitrogen applied to the mixture varied from 10 to 100 mg N per plant. Water supply was maintained at 15 to 35% of the mixture water holding capacity (stressed) to above 50% of capacity (well watered). Cumulative transpiration, steady‐state CO2 and H2O exchange rates, and dry matter were determined. The ratio of dry matter production (mmol C) to transpiration (mol H2O) averaged 1.39 and 1.94 mmol C mol−1 H2O for the 10 and 100 mg N treatments, respectively. The ratio of the steady state CO2 exchange rate to the H2O exchange rate was 1.97 and 4.24 mmol C mol−1 H20 for the 10 and 100 mg N treatments, respectively. The gas exchange WUE values tended to be higher than the gravimetric WUE values, but the two were correlated (r = 0.76**). Results supported the hypothesis that gas exchange WUE values could provide an accurate prediction of WUE values obtained from gravimetric analysis. Shootroot ratio was consistently reduced by N stress, but not by water stress. The results supported previous observations that optimal leaf N concentration promoted higher WUE. Mild water stress did not consistently affect WUE, but a more severe water stress consistently decreased WUE, especially under suboptimal N supply.
Tramlines, Row Orientation, and Individual Row Effects on Solid‐Seeded Soybean Plot Comparisons
Authors: Philbrook B. D. , Oplinger E. S. 
Published: July 2010

AbstractEvaluations of solid‐seeded soybean [Glycine max (L.) Merr.) and other crops in solid‐seeded research plots without damage to plants from equipment can be difficult. This study was conducted to determine how individual rows of solid‐seeded soybean plots responded to the additional space of tramlines within the border rows, and if the effects varied with row orientation or cultivar. Cultivars Evans, Hodgson 78, and Hardin were planted in the field in seven 0.18 m harvest rows and two 0.28 m border rows as plots in north‐south (N‐S) and east‐west (E‐W) orientations near Arlington, WI from 1983 to 1985. The additional space between harvest and border rows served as tramlines through the plots, and imparted 28% more area to each of the two outside harvest rows than each of the other harvest rows. East‐west row orientation had a lodging rating 0.4 units (0 to 5 scale) greater than N‐S orientation in 1984, but no yield difference. In 1985 N‐S orientation outyielded E‐W by 410 kg ha−1. Final plant stands in the rows next to tramlines averaged 10% less than the five center plot rows, but yields averaged 18% greater in compensation for the tramlines. The second rows from tramlines also yielded higher than three center rows, and contributed an additional 7% average yield. Performance estimates using seven rows between the tramlines were no different than those from the center three rows, which were guarded from the tramlines by two rows on each side. Cultivar yields varied, but relative performance was not influenced by tramlines or row orientations. We conclude that tramlines can be used in a plot planting system for accurately testing cultivars or treatments in solid‐seeded soybean.
Irrigation Method and Water Quality Effect on Peanut Yield and Grade
Authors: Adamsen F. J. 
Published: July 2010

AbstractPeanut (Arachis hypogaea L.), irrigated only recently in the coastal plain region of Virginia and North Carolina, is produced in an area where sodic deep water sources are more readily available than high quality shallow water sources. The objective of this work was to determine the effect of irrigation water quality and irrigation method on the yield and grade of peanut. Virginia‐type peanuts (cv. VA 81B) were grown on a Kenansville loamy sand (loamy, siliceous, thermic Arenic Hapludult) in Suffolk, VA from 1984 to 1987. Peanuts were irrigated with either overhead sprinklers or deep buried trickle lines using deep‐well (142 m) and shallow‐well (10 m) water. Trickle lines were buried 350 to 410 mm below each row. Deep‐well water had 220 mg Na L−1, a pH of 8.5, and a sodium adsorption ratio (SAR) of 103. Shallow‐well water had 4.8 mg Na L−1, a pH of 4.8, and an SAR of 3.1. Shallow‐well, trickle‐irrigated peanuts yielded 5003 kg ha−1 or 14% higher than the nonirrigated treatment. Deep‐well, sprinkler‐irrigated peanuts averaged 4374 kg ha−1 for 4 yr, which was 21 kg ha−1 lower than the nonirrigated treatment. The price of deep‐well, sprinkler‐irrigated peanuts was also lower than all other treatments due to lower percentages of extra‐large kernels, total sound mature kernels, and fancy pods. Deep‐well water applied below 300 mm through trickle irrigation produced peanuts of comparable quality and quantity as the shallow‐well, trickle, or sprinkler‐irrigation treatments. Irrigation of peanuts was beneficial in this humid region. There was no difference in peanut yield or grade when sprinkler or trickle irrigation was used with good quality irrigation water, but trickle irrigation required only 44% as much water. With a sodic water source, trickle irrigation was superior to sprinkler application.
Ethephon as a Morphological Regulator for Corn
Authors: Konsler J. V. , Grabau L. J. 
Published: July 2010

AbstractEthephon (2‐chloroethyl phosphonic acid) has been used to reduce ear height in order to improve lodging resistance of corn (Zea mays L.). However, untimely applications may reduce area of photosynthetically important ear leaves. Thus our objective was to determine the range of plant development stages over which ear height reduction could be achieved without advesrsely affecting ear leaf area. Two corn hybrids were space planted in the field in 1986 and 1987, and treated with ethephon at 284 g ha−1 over a range of vegetative growth stages. Ear heights were most reduced by ethephon applications from V9.2 to V10.6 in 1986 and at V13.0 in 1987. Individual internodes most influenced by ethephon were those actively elongating at the time of application. The area of the three ear leaves was most sensitive to treatments from V5.3 to V9.2 in 1986 and V6.0 to V8.8 in 1987. Early (V3.7 to V4.3) or late (V13.4 to V16.8) vegetative—stage application did not reduce grain yield per plant, while those treatments that most influenced area of ear leaves had a similar negative effect on grain yield. For the hybrids studied, the growth stages for which applications produced the best combination of ear height, ear leaf area, and grain yield were from V10 to V13, corresponding to developing tassel lengths of 30 to 300 mm. When ethephon rates were expressed as mg g−1 dry weight, more of variation in ear height, leaf area, and grain yield was explained than when rate was expressed as mg ethephon per plant. This implied that some growth regulator effects referred to as “timing” influences may be better explained as “dosage” effects. Additional research under higher planting rates will be necessary to validate these results.
Evaluating Plant Water Stress with Canopy Temperature Differences
Authors: Clawson K. L. , Jackson R. D. , Pinter P. J. 
Published: July 2010

AbstractThe temperature stress day (TSD) has been used as a remotely sensed indicator of plant water stress without a thorough knowledge of TSD behavior. The purpose of this study was to demonstrate a dependence of the TSD on net radiation (Rm), air temperature (Ta), and atmospheric water vapor pressure deficit (VPD), and to evaluate a replacement water status index. The dependence on these parameters was proven by the following methods: (i) theoretically, using the Penman‐Monteith resistance equation; (ii) empirically, using the non‐water‐stressed baseline equation relating canopy and air temperatures to VPD; and (iii) in a field experiment with alfalfa [Medicago sativa (L.)] on an Anthropic Torrifluvent soil. The effect of these parameters caused the field‐measured TSD to vary up to 7 °C, rendering its utility as a plant stress indicator questionable. A modification of the crop water stress index (CWSI), which accounts for Rn, Ta, and VPD, was proposed as the TSD replacement. The modification consisted of using a measured instead of estimated well‐watered canopy temperature (Tcl) in the canopy temperature ratio defined by the CWSI. This modification obviates the need for the canopy resistance value required to calculate the theoretically based CWSI. The modified CWSI responded to imposed irrigation regimes as indicated through yield and evapotranspiration comparisons. The modified CWSI appears to be a suitable replacement for the TSD by accounting for environmental dependence while maintaining the measurement simplicity of the TSD.
Light Competition Simulation Technique for Sod‐Seeded Crops
Authors: Evers G. W. 
Published: July 2010

AbstractCompetition for light is critical for successful establishment of clover in a perennial grass. This study was conducted to evaluate a greenhouse technique for screening germplasm for tolerance to reduced light. Tubes cut from PVC pipe were placed on ‘Bigbee’ berseem clover (Trifolium alexandrinum L.) seedlings at the cotyledon, unifoliate, and first and second leaf stages. Tube heights within each growth stage were 0,25, 51,76,102, and 152 mm. Weight, leaves, and nodules per seeding decreased as tube height increased while plant height did not decrease until the 76 mm tube. There was a general increase in these plant parameters as tube placement was delayed.
Yield and Quality Response of Subirrigated Meadow Vegetation to Nitrogen, Phosphorus and Sulfur Fertilizer
Authors: Nichols James T. , Reece Patrick E. , Hergert Gary W. , Moser Lowell E. 
Published: July 2010

AbstractProduction practices that increase hay yields are important for beef cattle producers in the Nebraska Sandhills. This study evaluated the responses of subirrigated meadow vegetation to fertilization with N, P, and S over a 4‐yr period. A factorial array of four levels of N (0, 45, 90 and 135 kg ha−1), two levels of P (0 and 20 kg ha−1) and two levels of S (0 and 22 kg ha−1) were applied each year to the same plots, arranged in a randomized complete block design. Average dry matter yields were increased by N, P, and S. There were no fertilizer interaction effects. Yields increased quadratically as N levels increased. For each 45 kg increment of N applied from 0 to 135 kg ha−1, dry matter yield (pooled over P and S) increased 1002, 703, and 402 kg ha−1, respectively. Main effects of P and S increased dry matter yields by 4662 and 577 kg ha−1, respectively. Nitrogen uptake was increased linearly by fertilization with N, P, and S. Forage N use efficiency decreased as N fertilizer rates increased. Crude protein (CP) declined quadratically as N rates increased, but the maximum change was less than 10 g kg−1. In vitro dry matter digestibility (IVDMD) declined linearly as N rates increased. Sulfur and P did not affect either CP or IVDMD. Yield responses were sufficient to justify the use of N, P, and S to increase subirrigated meadow production. Loss of forage quality (CP and IVDMD) was not sufficient to nullify this conclusion.
Spring Wheat Response to Herbicides Applied at Three Growth Stages
Authors: Martin Duane A. , Miller Stephen D. , Alley Harold P. 
Published: July 2010

AbstractSince the inception of 2,4‐D [(2,4‐dichlorophenoxy) acetic acid], many herbicides have been developed for broadleaf weed control in wheat (Triticum aestivum L.). However, many of these herbicides have not been thoroughly evaluated with respect to application timing and effects on wheat yield and quality. Field studies were conducted at Torrington, WY on a Bayard fine sandy loam (coarse loamy, mixed, mesic Torriothentic Haplustoll) in 1984 and 1985 to evaluate the response of ‘Oslo’ spring wheat to 10 broadleaf herbicide treatments applied at three growth stages. Dicamba (3,6‐dichloro‐2‐methoxybenzoic acid), dicamba plus 2,4‐D and dicamba plus MCPA [(4‐chloro‐2‐methylphenoxy)acetic acid] reduced wheat yield 28, 21 and 24%, reduced kernels per spike 27, 33 and 21%, and increased seed protein 8, 10 and 13%, respectively, when applied at Zadoks Stage 44 (mid‐boot). Several other auxin herbicides increased seed protein content, particularly when applied at Zadoks Stage 44. Proline and lysine content were not influenced by herbicide treatment at any stage of application. Spring wheat tolerance to bromoxynil (3,5‐dibromo‐4‐hydroxybenzonitrile), chlorsulfuron (2‐chloro‐Ar‐[[4‐methoxy‐6‐methyl‐l,3,5‐triazin‐2‐yl)amino]carbonyl] benzenesulfonamide} and MCPA was excellent regardless of growth stage at application.
A Soil Water Balance and Dry Matter Production Model: I. Soil Water Balance of Oat
Authors: Ragab R. , Beese F. , Ehlers W. 
Published: July 2010

AbstractA simulation study of the soil water balance under oat (Avena sativa L.) was carried out on a Typic Hapludalf soil, at two sites near Göttingen, West Germany during 1976,1977,1982, and 1983. The model used describes the plant water uptake rate as a function of soil matric potential and rooting depth. Inputs needed for the model are soil physical parameters, daily meteorological data, rooting depth, leaf area index, and plant height. The goal was to test the usefulness of the model in predicting the soil water balance components and to determine if the plant water uptake rate, as a potential important factor for crop yield, can be simulated by applying a rather simple approach. Simulated water uptake rate, actual evapotranspiration rate, water storage in the soil profile, and soil water profiles, compared reasonably well with the measured values in the 4 yr studied. Since some of the model input parameters were derived from the 4‐yr experimental data, the model remains to be tested against an entirely independent data set.
A Soil Water Balance and Dry Matter Production Model: II. Dry Matter Production of Oat
Authors: Ragab R. , Beese F. , Ehlers W. 
Published: July 2010

AbstractA simulation study on dry matter production of oat (Avena sativa L.) was carried out on a Typic Hapludalf, at two sites near Göttingen, West Germany, during 1976,1977,1982, and 1983. The model used in this study is a Blackman‐type production model in which a maximum production level is considered. The model simulates the yield as a function of radiation energy and water supply in the presence of an optimal nutrient supply. Input values required include daily climatic data, canopy parameters, and water uptake rate. The aim was to test the usefulness of the model when a complete field data set is available. The results indicate that the simulated values for total dry matter (shoot + roots) and shoot dry matter compared well with measured values. The sensitivity analysis showed that careful consideration should be given to the input values for maximum water use efficiency and respiration factors. The study reveals that oat dry matter production can be simulated, provided that the proper parameters are used. Since some of the required inputs were derived from the 4‐yr experimental data, the model remains to be tested against a truly independent data set.
Computer Program to Print Adhesive Identification Labels for Research
Authors: Graff Paul S. , Hipp Billy W. 
Published: July 2010

AbstractUsing microcomputers to produce adhesive labels for research samples saves time and effort, and reduced potential for errors in labeling. To our knowledge, no programs written solely for this purpose have been made publicly available for personal computers using MS‐DOS.1 Our program produces sequentially incremented labels using “skeletal” information such as study title/location, list of treatments, number of replications, and material(s) sampled. Templates with this information can be stored and recalled for individual experiments. Bar codes (UPC, Uniform Code Council, Inc., Dayton, OH, and Code‐39 Interface Mechanisms, Inc., ynnwood, WA) with encoded treatment/replication information are optionally printed. The program requires 185K RAM, a 360K floppy disk drive, a printer, and continuous‐form (pin‐fed) adhesive labels.
Potassium Uptake and Recovery by an Upland Rice‐Soybean Rotation on an Oxisol
Authors: Gill D. W. , Kamprath E. J. 
Published: July 2010

AbstractA major limitation to improved crop growth on many acid Oxisols is low K availability. A field experiment was conducted in West Sumatra to study the effects of K fertilization of an oxisol under three levels of lime (0.375, 2.25 an 5 t ha−1) on K accumulation of a yearly upland rice (Oryza sativa L.)‐soybean (Glycine max L. Merr.) rotation where all above‐ground residue was removed. Six K treatments supplied 0 to 240 kg K ha−1 to each crop and lime treatment. Potassium fertilization increased grain yields of rice and soybean and K content of grain and stover of both crops. With both crops a large proportion of the K was present in the stover. Liming had no effect on K accumulation Of rice grain; an inconsistent effect on K accumulation in rice straw; and significantly increased the K content of soybean grain and stover. Upland rice was very efficient in utilizing K applied to that crop as well as residual soil K from previous fertilization. When K rate was greater than 100 kg ha−1 per crop appreciable amounts of K could not be accounted for indicating that the K was lost by leaching. Increases in exchangeable K with K fertilization only occurred in the 0‐ to 30‐cm depth.
Cluster Analyses for Analyzing Two‐Way Classification Data
Authors: Lin C. S. , Butler G. 
Published: July 2010

AbstractThe interaction structure of two‐way classification data often can be identified if the data are stratified into homogeneous subsets. Four cluster methods, two new and two originally developed for investigating genotype × environment (GE) interaction, are proposed for this purpose. The four methods differ in the dissimilarity indices depending on whether the regression model or ANOVA model is used, and whether the similarity is specified with respect to the GE interaction alone or with respect to the genetic effect and GE interaction combined. The same cluster algorithm of averaging the dissimilarity indices between all pairs of individuals in the two groups is used for all. A unique feature of these methods is that the dissimilarity index defined or constructed at any cluster cycle, is equivalent to the mean square of the respective ANOVA for the grouped genotypes. The direct link between the cluster analysis and conventional ANOVA provides a convenient way of determining the cutoff point based on tire F‐ratio of the smallest dissimilarity index and the error estimate. When the calculated F‐ratio exceeds the tabular F‐value the cluster process should be stopped. Since the smallest dissimilarity index at each cluster cycle is monotonically increasing, this stopping rule assures that all individuals within the groups are homogeneous with respect to defined characteristics. The stratification of data sets (by these methods) leads to the revelation of complex data structures as demonstrated by several works cited.
Structure of Tall Fescue Swards and Intake of Grazing Cattle
Authors: Arias J. E. , Dougherty C. T. , Bradley N. W. , Cornelius P. L. , Lauriault L. M. 
Published: July 2010

AbstractModels of grazing systems need logic that estimate herbage intake of livestock from physical and chemical properties of the sward. Changeover designs were used to study the effects of sward structure of tall fescue (Festuca arundinacea Schreb. cv. Kenhy) on ingestive behavior of grazing cattle. Fourteen (Tl), 21 (T2), and 28 (T3) days of growth established sward surface heights of 16, 20, and 22 cm, with herbage dry matter (DM) masses (>5 cm) of 0.84, 1.43, and 2.16 Mg ha−1. When each of 12 2‐yr‐old Angus heifers (Bos taurus L.) (liveweight, 381 kg) were allocated the same grazing area (26 m2), with DM allowances (>5 cm) of 2.2,3.7, and 5.6 kg for 90 min of grazing, heifers ingested DM at 1.07, 1.65, and 2.03 kg h−1, with herbage DM intakes per bite of 0.45, 0.65, and 0.82 g and consumption of 75, 69, and 57% of allowance for T1, T2, and T3, respectively. Rates of biting were not flected by sward treatments and averaged 42 bites min−1. The grazing horizon of the vegetative tall fescue tillers was limited to a plane above the tops of pseudostems and ingestive behavior reflected the properties of herbage in that horizon.
Minimum User‐Interface Standards and Software for Agricultural Expert Systems
Authors: Meyer C. R. 
Published: July 2010

AbstractAgricultural Expert Systems (AES) are gaining recognition as technology transfer devices. It is increasingly clear that lack of uniformity in their presentation to the user creates unnecessary obstacles to their acceptance. Some agronomic expert system applications require performance and economy not currently available with commercial expert system development shells.A group of expert system developers resolved to establish uniform standards for the part of an AES a user must interact with. A committee was appointed to draft the standards from their collective experience. Software was developed to implement these standards in expert systems, without sacrificing performance and economy. Two lists of standards were developed: mandatory and desirable. These are minimal features, and extended or enhanced features, respectively. The lists were compiled and refined through study of existing programs, current definitions, developers' experience, and user input. Software to meet the standards was developed in C language, in conjunction with an expert system. This permitted interactive refinement of both the standards and the software. The standards for AES features were endorsed by two groups of cooperating AES developers. Public domain source code is available to implement the features mentioned above, in the C programming language. Concurrence upon the two lists of standards proved to be possible. Adherence to such standards is desirable, since it reduces user confusion. Including these features in programs not usually thought of as expert systems, is easy, inexpensive, and greatly increases their acceptability to new users.