bluuebunny/crossref_metadata_2025_split huggingface dataset:
SOYHERB‐A Computer Program for Soybean Herbicide Decision Making
Authors: Renner K. A. , Black J. R. 
Published: July 2010

AbstractThere has been a rapid increase in the number of herbicides and herbicide mixtures registered for use in soybean [Glycine max (L.) Merr.] production. SOYHERB is a computer program developed to assist Cooperative Extension Service personnel, agribusiness, farmers, and teachers in determining herbicide options for soybean production. Tillage practices, atrazine (6‐chloro‐N‐ethyl‐N'‐(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine) or simazine (6‐chloro‐N,N'diethyl‐1,3,5‐triazine‐2,4‐diamine) use in a previous corn crop, soil type and percentage of organic matter, soil pH, projected crop rotation plans, method of herbicide application, and weed species and weed pressure are entered by the user. SOYHERB generates herbicide programs and their cost per acre that provide excellent control of all weed species at the weed pressures indicated. Fair (80–90%) weed control options may also be generated. Additional screens describe control of perennial weeds, a summary of herbicide premixes, and a table listing the maximum height of broadleaf weeds controlled by postemergence herbicides. Data can be saved for future reference. A computer capable of running MS‐DOS or PC‐DOS version 2.1 or greater with a minimum of 512K bytes of RAM is required.
Computing Transpiration of Sunlit and Shaded Cotton Foliage under Variable Water Stress
Authors: Petersen K.L. , Fuchs M. , Moreshet S. , Cohen Y. , Sinoquet H. 
Published: July 2010

AbstractThe accurate calculation of transpiration from plant canopies is critical in order to judiciously manage limited water resources in many agricultural areas. The objective of this study was to compute transpiration from the sunlit and shaded fractions of a cotton (Gossypium hirsutum, cv, Acala SJ2) canopy using the Penman‐Monteith energy balance equation. These computations were validated by a heat pulse system measuring stem sap flow, and by measuring the crop surface energy balance by the Bowen ratio method during two field seasons in 1988 and 1989. Adjusting the relationship between absorbed radiation and leaf conductance for decreasing leaf water potential sensitized the Penman‐Monteith energy balance computation to variable water stress conditions. Results showed that the computed transpiration of the shaded canopy comprised 0.21, 0.28, and 0.33 of the total during severe water stress in normal atmospheric demand, non‐stress in normal atmospheric demand, and non‐stress in very high atmospheric demand, respectively. The average daily computed transpiration for the two seasons was within 5% of that measured by the heat pulse system and the Bowen ratio. The hourly computation exhibited the expected sensitivity to fluctuations in atmospheric demand and to the change of available soil moisture. The linear regression of computed transpiration for measured water uptake by the heat pulse system yielded an R2 value of 0.96. Quadratic regression analyses during non‐stress and stress for computed hourly transpiration vs. evapotranspiration yielded R2 values of 0.97 and 0.92, respectively. These analyses show that midday evapotranspiration is systematically higher than computed transpiration, which would presumably be due to evaporation from the soil.
Fertilizer Management Effect on Recovery of Labeled Nitrogen by Continuous No‐Till
Authors: Timmons D. R. , Baker J. L. 
Published: July 2010

AbstractImproved fertilizer N management with respect to placement and timing is especially important in high‐residue systems designed to improve N‐use efficiency and to speed adoption of erosion controlling tillage practices. By means of point‐injection technology, fertilizer solutions now can be applied and soil‐incorporated with minimal disturbance of surface residue or existing plants. This study was conducted in large non‐weighing lysimeters (with reconstituted soil horizons) to determine the recovery of 15N – labeled urea‐ammonium nitrate (UAN) solution by continuous no‐till corn (Zea mays L.) during the initial year of application and two subsequent years for four N management systems. The UAN solution was point‐injected in split applications at rates of 125 or 200 kg N ha−1, or knifed‐in or surface‐banded right after plant emergence at 200 kg N ha−1. For the initial year of 15N application, the percent recovery of labeled N (NR) in grain was 48, 39, 33, and 30% for point‐injected (low rate/split), point‐injected (high rate/split), knifed‐in, and surface‐banded, respectively. The percentage of total grain N derived from labeled N (Nf) ranged from 57 to 67% and was in the order of point‐injected (high rate/split) > knifedin > point‐injected (low rate/split) > surface‐banded. Residual labeled N recovery in grain ranged from 2.3 to 4.6% for the second season and from 0.9 to 1.0% for the third season with no significant differences among application treatments for either season. After five seasons the NR values for labeled N determined in the soil N pool still ranged from 20 to 26%. UAN solution applied in split applications with the point injector was used more efficiently by corn than when knifed‐in or surface‐banded in a single application, indicating the point‐injection/split application system is an option for improved N management in no‐till corn.
Crabgrass Control In Coastal Bermudagrass
Authors: Smith A. E. , Martin L. D. 
Published: July 2010

AbstractMany hectares of ‘Coastal’ bennudagrass [Cynodon dactylon (L.) Pers.] stands are lost during the second growing season after planting because of competition from large crabgrass [Digitaria sanquinalis (L.) Scop]. Experiments were conducted in southern Georgia on a Cecil (thermic, Typic Hapludults) sandy clay loam and central Georgia on a Greenville (clayey, thermic, Rhodic Kandiudults) sandy loam soil to evaluate chemical treatments for managing large crabgrass in Coastal bermudagrass. Herbicide treatments were applied to Coastal bermudagrass stands during the second growing season after planting to evaluate crabgrass control and to fully established stands to determine treatment damage to the Coastal bermudagrass. Norflurazon {4‐chloro‐5 ‐ (methylamino)‐2‐[3 ‐ (trifluoromethyl)phenyl] ‐3(2H)‐pyridazinone} applied during March at rates of 1.12 and 2.24 kg ai ha−1 resulted in >80% control of large crabgrass up to 90 and 50 d after treatment, respectively. Treatments with norflurazon at rates as high as 2.24 kg ha−1 did not damage the Coastal bemudagrass stand or decrease yield compared to the untreated control. These data indicate that norflurazon would be an excellent candidate herbicide for use in the control of large crabgrass in Coastal bermudagrass pastures and hayfields.
Yield and Quality of Soybean Forage as Affected by Cultivar and Management Practices
Authors: Hintz Rodney W. , Albrecht K. A. , Oplinger E. S. 
Published: July 2010

AbstractSoybean [Glycine max (L.) Merr.] has potential for use as an alternative forage crop, however, little is known about the effects of cultural practices on forage yield and quality. A study was conducted to evaluate the effects of cultivar, row spacing, plant density, and harvest maturity on the yield and quality of soybean forage. The study was conducted at the Univ. of Wisconsin Arlington Agricultural Research Station, Arlington, WI on a Plano silt‐loam soil (fine‐silty, mixed, mesic, Typic Argiudoll) in 1987 and 1989. The cultivars Corsoy 79, Pella, and Williams 82 were grown at 20‐ and 76‐cm row spacings at planting rates of 280 000 and 890 000 seeds ha−1 and were harvested at the R1, R3, R5, and R7 stages of development. Harvest maturity had the greatest effect on soybean forage yield and quality of the management practices evaluated. The yield of soybean forage increased from 2.4 Mg ha−1 when harvested at R1 to 7.4 Mg ha−1 when harvested at R7, but quality declined between stages R1 and R5 then increased from R5 to R7 as pods developed and seeds filled. Late maturing cultivars (Maturity Group III vs. Maturity Group II) produced greater forage yields but lower quality forage when harvested at the same stage of development. The 20‐cm row spacing produced 1.2 Mg ha−1 more forage than the 76‐cm row spacing, but crude protein concentration was 8 g kg−1 less. The results of this experiment indicate that soybean can produce forage similar in quality to alfalfa and that management practices typically used for grain production are suitable for forage production.
Soil Moisture Extraction by Vegetation in a Mediterranean/Maritime Climatic Regime
Authors: Borman M. M. , Johnson D. E. , Krueger W. C. 
Published: July 2010

AbstractTiming and extent of soil moisture extraction are critical when evaluating perennial grasses for their adaptability to the climate and soils. We hypothesized that in the southwest Oregon foothills perennial grasses able to extract moisture early in the growing season should be more competitive with resident annual plants than those that utilize soil moisture later. Our objective was to assess the potential for competition of selected native and introduced perennial grasses with annual plants. The experiment consisted of growing perennial grasses with and without competition from the resident annual community and evaluating soil moisture throughout the growing season with a neutron probe. ‘Berber’ and ‘Palestine’ orchardgrasses (Dactylis glomerata L.) extracted moisture earlier than later growing ‘Oahe’ intermediate and ‘Alkar’ tall wheatgrasses (Agropyron intermedium [Host.] Beauv. and A. elongatum [Host.] Beauv., respectively). Soil moisture contents in plots of Idaho fescue (Festuca idahoensis Elmer), a native and the earliest growing and maturing perennial grass in the study, were not consistently lower than soil moisture contents in plots of later growing perennial grasses. End‐of‐season soil moisture contents were similar (P < 0.10) in perennial grass plots and plots dominated by yellow starthistle (Centaurea solstitialis L.). Resident annual grasses left approximately 50% more soil moisture than perennial grasses or annual forbs. In years with an early summer drought, earlier growing perennial grasses should be able to satisfy their growth requirements.
Analysis of Phytomass Yield in Wheat
Authors: Sharma R. C. 
Published: July 2010

AbstractGrain yield (GRY) increases in wheat (Triticum aestivum L.) have been achieved through increases in harvest index (HI). Further improvements in HI appear difficult so further increases in GRY may have to come through increases in phytomass yield (PMY). Increases in PMY also should increase yield of nongrain plant parts (NGRY) which is important both for wheat pasture and for feeding straw to cattle in developing countries. A study was undertaken to examine variation for PMY in 20 genetically diverse wheat genotypes and to analyze GRY and NGRY constituents of PMY. Replicated field tests were conducted at Rampur, Nepal in 1989 and 1990 under two production systems. There were significant effects of year and production system on PMY, GRY, NGRY, and HI. Significant genotypic variations existed for PMY, GRY, NGRY, and HI. All genotypes produced higher PMY, GRY, and NGRY under high fertility production system than under low fertility production system. Genotype‐by‐production system interactions were significant for PMY, GRY, and NGRY and genotype‐by‐year interactions were significant for PMY, NGRY, and HI. High PMY usually resulted in high GRY and high NGRY which is desirable in developing countries where both GRY and NGRY determine the economic success of a cultivar. The presence of high positive correlations between PMY and GRY (r = 0.84, P < 0.01), PMY and NGRY (r = 0.94, P < 0.01), and an intermediate positive correlation between GRY and NGRY (r = 0.60, P < 0.01) suggested that these traits might be selected simultaneously for improvements.
Phenmedipham + Desmedipham Effects on Sugarbeet
Authors: Prodoehl K. A. , Campbell L. G. , Dexter A. G. 
Published: July 2010

AbstractPhenmedipham + desmedipham [3‐methoxycarbonylaminophenyl‐3‐methylcarbanilate plus ethyl m‐hydroxycarbanilate carbanilate (ester)], is a herbicide which controls a number of broadleaf weeds in sugarbeet (Beta vulgaris L.) by inhibiting Photosystem II. This hericide also decreases the photosynthetic activity of sugarbeet. Field tests at Fargo, ND, in 1988, 1989, and 1990 determined the effect of phenmedipham + desmedipham on photosynthesis 1, 3, and 10 d after treatment (DAT); root yield; and sucrose concentration of six commercial sugarbeet cultivars. Photosynthesis was reduced 50 and 30% 1 DAT with high and low rates of phenmedipham + desmedipham, respectively, but recovered substantially 10 DAT to 75 and 85% of the untreated plots. Small reductions in root yield associated with phenmedipham + desmedipham rates were not significant. Sucrose concentration at harvest was not influenced by phenmedipham + desmedipham. No cultivar or group of cultivars was identified as having a unique response to phenmedipham + desmedipham.
Nodulation, Nitrogen Fixation, and Early Growth of Arrowleaf Clover in Response to Root Temperature and Starter Nitrogen
Authors: Schomberg H. H. , Weaver R. W. 
Published: July 2010

AbstractNitrogen availability is important for rapid establishment of small seeded legumes and is influenced by soil N status and rapid development of N2 fixation activity. Seedlings of arrowleaf clover (Trifolium vesiculosum L. Savi) are exposed to soil temperatures (10–35°C) during the fall which can reduce seedling vigor by influencing N nutrition. Root temperature (18, 25, or 32 °C) effects on N nutrition of arrowleaf clover receiving starter N was evaluated in two controlled experiments. Temperature influenced the N status of inoculated plants through an effect on N2 fixation but not on starter N uptake. Growth and N2 fixation were best at 25 °C where effectiveness of two strains of Rhizobium leguminosarum bv. trifolii was similar, but, at 32 °C, strain RP115‐2 was less effective than strain 162✕68. Addition of mineral N (0.5 and 1.0 mg N plant−1) improved growth and stimulated N2 fixation at 25 °C more than at 18 or 32 °C. Time required for nodulation was also influenced by N and temperature but was not different between the two strains of Rhizobium. Nodules were first visible 6.4 to 8 d following inoculation at 25°C, but required 8.0 to 11.3 d at 18 or 32°C with the longer period occurring for plants receiving 1.0 mg N plant−1. Growth of control plants receiving adequate mineral N showed little influence of the root temperature regimes. Root temperatures influenced early growth of arrowleaf clover through an effect on N2 fixation and root temperatures of 32 °C or greater were particularly detrimental because of combined effects of delayed nodulation and reduced N2 fixation activity.
Core Cultivation of a Putting Green with Hollow and Solid Tines
Authors: Murphy J. A. , Rieke P. E. , Erickson A. E. 
Published: July 2010

AbstractMost turfgrass soil cultivation research has emphasized water infiltration and thatch responses, but has provided limited information regarding detailed soil and rooting responses to different cultivation methods. This study evaluated cultivation effects on soil physical properties and turf growth of a ‘Penneagle’ creeping bentgrass (Agrostis palustris Huds.) putting green. Cultivation, utilizing vertically operating hollow (HTC) or solid (STC) tines, was applied over a 3‐yr period on a loamy sand soil (modified fine‐loamy, mixed, mesic, Typic Hapludalfs). Cultivation treatments were applied on noncompacted and compacted plots, and at soil moisture potential ranges of −40 to −60 kPa (moist) or −2 to −4 kPa (wet). Saturated water conductivity and air porosity was 49 and 21% greater, respectively, with HTC than STC. After three seasons, wet soil cultivation reduced saturated hydraulic conductivity 31% compared to moist soil cultivation. Cultivation reduced penetration resistance 45% at the 5‐cm depth compared to noncultivated plots in compacted soil, but the benefit was transient particularly on STC plots. Hollow tine cultivation under wet soil conditions yielded the best turf quality. Surface root weight density was lowered 20% with cultivation on compacted soil by the end of the study. Hollow tine cultivation lowered the organic matter fraction of the thatch/mat layer 0.24 kg kg−1, but increased total organic matter content 150 g m−2 compared to solid tine cultivation. Solid tine cultivation provided short term benefits, required repeated application to be effective in management of soil compaction, and exhibited the potential for development of a cultivation pan.
Timing Nitrogen Applications for Corn in a Winter Legume Conservation‐Tillage System
Authors: Reeves D. W. , Wood C. W. , Touchton J. T. 
Published: July 2010

AbstractFertilizer N efficiency of corn (Zea mays L.) in conservation‐tillage systems with winter legumes such as crimson clover (Trifolium incarnatum L.) can possibly be improved by better synchronization of legume‐N release, fertilizer‐N application time, and crop demand for N. The objective of this 3‐yr (1986‐1988) field experiment was to determine the effect of N application time on dry matter accumulation, N uptake, and grain yield of corn grown in a winter legume conservation‐tillage system. Corn was planted with unit planters into crimson clover residue following in‐row subsoiling. The clover was killed at midbloom every year. Treatments were a factorial arrangement of fertilizer N rates and application time. Nitrogen as NH4NO3 was broadcast at rates of 34, 67, and 134 kg ha−1. Zero‐N checks were also included in both clover and rye (Secale cereal L.) plots. Application times were at planting, or 3, 6, or 9 wk later. In addition, split applications (1/3 at planting and the remainder 6 wk later) of the 67 and 134 kg N ha−1 rates were included. In 2 of 3 yr, dry matter accumulation was not affected by N application time. In 1987, however, dry matter production was greater when N was applied at planting compared to split applications or applications later than 3 wk after planting. Application time affected N uptake patterns during the growing season, but generally did not affect total N uptake at the end of the season. With the exception of the first year, split N applications resulted in equivalent or reduced N uptake compared to application of all N at planting. Based on linear regression models, maximum yield was obtained with 134, 116, and 93 kg N ha−1 in 1987, 1988, and 1989, respectively. After the first year, applying N later than 6 wk after planting reduced grain yield and split applications of N were not effective in increasing grain yield. These results suggest that the fertilizer N requirement of corn grown in winter legume conservationtillage systems on Coastal Plain soils decreases with successive years in the system and that the optimum management practice for conservation of N, energy, time, and labor would be to apply all fertilizer N at planting.
Mineral Concentrations in Forage Sorghum Grown under Two Harvest Management Systems
Authors: Kidambi S. P. , Matches A. G. , Karnezos T. P. , Keeling J. W. 
Published: July 2010

AbstractLittle information is available on the mineral concentrations of forage sorghum [Sorghum bicolor (L.) Moench] leaves and stems. Our objective was to determine whether commercially available forage sorghum could be expected to supply the minimum mineral requirements for beef cattle when harvested as simulated grazing of pastures (SP) or as hay. In 1987 and 1988, 10 forage sorghum entries were grown near Lubbock, TX, in replicated plantings on a fine, mixed thermic Aridic Paleustolls with supplemental furrow irrigation. There were three SP harvests in 1987 and four in 1988. The hay treatments were harvested twice in 1987 and three times in 1988. Entries and managements were different (P ≤ 0.05) in mineral concentrations, as was the management ✕ entry interaction for Mg, K, Na, Cu, and the K/(Ca + Mg) ratio. Generally, for both management systems, leaves had numerically higher concentrations of Ca, Mg, P, and Mn than stems, while the reverse was true for K, Na, and the K/(Ca + Mg) ratio. Copper and Zn concentrations were not consistent for either harvest schedule or leaves and stems. Minerals found most likely to be limiting for beef cattle (Bos taurus) were P and Zn, but P would generally be adequate if cattle had daily access to leafy growth. Calcium tended to be low and the K/(Ca + Mg) ratio high in stems of the hay harvests. The levels of the other minerals appeared to meet the minimum requirements for beef cattle for most of the growing season. Overall, the 10 entries of forage sorghum appeared similar in meeting mineral requirements of beef cattle.
Nitrogen Credits in Soybean‐Corn Crop Sequences on Three Soils
Authors: Bundy L. G. , Andraski T. W. , Wolkowski R. P. 
Published: July 2010

AbstractEconomic and environmental incentives to accurately predict corn (Zea mays L.) N requirements emphasize the need to assign appropriate N credits for soybean (Glycine max L.) in soybean‐corn crop sequences. This study was conducted to determine corn response to N and N credits for soybean in crop sequences. The effects of corn‐corn (CC), soybean‐corn (SbC), and soybean‐corn‐corn (SbCC) crop sequences and applied N (0 to 225 kg N ha−1) on corn grain yield, N uptake, and soil NO3 and NH4 concentrations were determined for 4 yr at three sites differing in climatic and soil characteristics. Four‐year mean yields in SbC were 1.4 and 2.2 Mg ha−1 higher than in CC at two sites with nonirrigated silt loam soils, but yield effects due to crop sequence were small on an irrigated sandy soil. Corn response to applied N varied markedly among the three sites and between years at the sites on silt loams soils. Mean corn N uptake in SbC was higher (51 kg N ha−1) than in CC on silt loam soils but not on the sandy soil. Soybean N credits estimated with a fertilizer replacement value (FRV) approach and from the difference in N rates at maximum yield in SbC and CC sequences (DNM) differed markedly among locations and years and ranged from − 22 to 210 kg N ha−1. Soybean provided little N to subsequent crops on sandy soils due to probable loss of residue N through leaching prior to use by the following crop. On silt loam soils, crop sequence effects on yield and N uptake indicate soybean N contributions to subsequent crops; however, fixed value N credits or N credits based on N response data combined over years will seldom accurately predict actual soybean N contributions. Site‐specific diagnostic tests are needed to improve crediting of N supplied by soybean in crop sequences.