bluuebunny/crossref_metadata_2025_split huggingface dataset:
Double Cropping Following Winter Barley Harvest in Eastern Virginia1
Authors: Camper H. M. , Genter C. F. , Loope K. E. 
Published: July 2010

AbstractSoybeans (Glycine max L.) for grain and sorghum (Sorghum vulgare L.) and maize (Zea mays L.) for both grain and silage were planted in late June and in July following winter barley (Hordeum vulgate L.) to evaluate these crops in a double cropping system in eastern Virginia. Soybeans have been widely grown after barley in that area. Production and harvest costs were estimated and net returns were calculated from these estimates and the values of the crops produced.Grain yields were obtained over a 2‐year period. Both mid‐season and late maturity soybeans produced crops of satisfactory quality each year. Early or very early maturity sorghum and maize hybrids were planted and appeared to be satisfactory for grain when planted in June but one July planting was severely damaged by an early frost.When the June plantings were harvested for grain, the net return from maize was significantly greater than from either sorghum or soybeans. Soybeans, however, appeared to be more dependable than maize or sorghum for grain if planted in July.Maize and sorghum silage yields were obtained the second year of the experiment. Net returns from both crops for silage were consistently greater at each date of planting than from any grain crop. All but one of the differences were significant. Net returns were greater from sorghum silage than from maize at each date of planting and the difference was significant for the July planting.Better adapted strains of all three crops are needed for use in a double cropping system.
Orientation and Distribution of Leaves Within Soybean Canopies1
Authors: Blad Blaine L. , Baker Donald G. 
Published: July 2010

Abstract‘Chippewa 64’ and ‘Hark’ soybean [Glycine max (L.) Merr.] varieties were studied at Lamberton and St. Paul, Minn. The average leaf sizes, numbers, and total leaf area index were determined during the growing season. The distribution of leaf area with height was obtained in the field and in a controlled environment chamber. The chamber‐grown plants exhibited a distribution similar to the area distribution of a cylindrical cross‐section. The field‐grown soybeans had most of the leaf area near the upper portions of the plant canopy and did not have a cylindrical distribution. These variations in leaf area distributions are largely explained by differences in the light intensities at the lower canopy levels with the different growing conditions.Measurements of the azimuth directions of the soybean leaflets revealed that soybean leaves do not show any preferred direction. Leaf inclination distributions showed that soybean canopies were planophile through most of the growing season, except in the early and lategrowth stages, when the leaves were almost evenly distributed among all inclination classes. The Hark variety had smaller and slightly more vertically oriented leaves than the Chippewa 64 variety, which would allow greater penetration of light to the lower canopy levels.
Dryland Evaporative Flux in a Subhumid Climate: III. Soil Water Influence1
Authors: Ritchie Joe T. , Burnett Earl , Henderson R. C. 
Published: July 2010

AbstractThis investigation was conducted to determine the relationship between evaporative rates of field‐grown cotton (Gossypium sp.) and grain sorghum [Sorghum bicolor (L.) Moench] and the soil water status for use in predicting evaporation on watersheds.Soil water content and soil water matric potential of Houston Black clay were measured throughout complete growing seasons for cotton and grain sorghum concurrently with measurements of the daily evaporation rate. Evaporation rates were independent of the soil water status until soil water was depleted beyond a threshold value. This threshold, termed the lower limit for potential evaporation (LLE0), was reached when approximately 18.2 cm of water had been removed from a soil profile initially wet. Another 6.5 cm of soil water was extracted at a decreasing rate before evaporation practically stopped. Evaporation rates after the LLE0 threshold was reached were practically independent of the energy available for evaporation and depended on the rooting distribution and the water movement to the roots. An analysis of the soil water transmission characteristics after the threshold LLE0 was reached showed that practically all the water extracted by plant roots was moving from the volume of soil immediately surrounding the roots. This result points out the need for growing crops with deep, dense root systems in dryland for maximum utilization of stored soil water.
Environmental Influences on the Leaf Temperatures of Two Soybean Varieties Grown under Controlled Irrigation1
Authors: Carlson Richard E. , Yarger Douglas N. , Shaw Robert H. 
Published: July 2010

AbstractRemote sensing techniques have been suggested as a possible tool to the agricultural research worker. In addition, plant leaf temperatures (a quantity capable of being measured by remote sensors) give an indication of the plant's response to the environment. For these reasons, an experiment was conducted in the field to investigate the relations between plant leaf temperatures and soil moisture stress and various environmental parameters.Leaf temperatures (TL) of two soybean [Glycine max (L.) Merr.] varieties grown under controlled irrigation were measured with an infrared thermometer during a 9‐day experiment. On a given day relative leaf water content (RWC) and TL were highly correlated. When TL's were examined over different days, vapor pressure deficit (VPD) and air temperature (TA) were found to affect TL· TL increased with decreasing values of both RWC and VPD. Interactions involving both VPD and TA with RWC were observed. TL increased with increasing TA; however, the amount of increase of TL seemed related to the leaf's level of RWC. This was related to increased transpirational cooling (stomatal conductivity) at higher levels of TA. The two varieties in this experiment were significantly different with respect to TL, but the degree of significance was related to VPD.
No‐Till Corn in Fescuegrass1
Authors: Carreker John R. , Box James E. , Dawson Royal N. , Beaty E. R. , Morris H. D. 
Published: July 2010

AbstractThe rolling soils of the Southern Piedmont are highly erosive when clean tilled. The area is well adapted to close‐growing forage crops, but the thriving poultry industry in this region needs more grains. By combining no‐till corn (Zea mays L.) production on fescuegrass (Festuca elatior, var. arrundinacea) sod with irrigation and adequate fertilization, a number of problems might be solved.Corn was grown on Cecil sandy loam following corn and in live fescuegrass with and without irrigation in 1969, and by no‐till planting in live, stunted, and killed fescuegrass with and without irrigation in 1970. Nitrogen rates applied to the corn were 148 kg/ha in 1969 and 112, 224, and 448 kg/ha in 1970.Without irrigation, the corn and the live grass exhausted all available soil water during droughts in June, and the corn died. Corn growth in the stunted and killed sods was reduced, but the plants lived. With irrigation the corn and live grass used soil water faster than corn in dead sod until the corn developed a complete canopy. After the canopy developed, corn in killed sod used more soil water than did the corn in live sod. Without irrigation, corn yields were O with live sod and about 1000 kg/ha on killed sod and showed no response to N levels of 112, 224, and 448 kg/ha. With irrigation, yields were directly proportional to N levels and to the amount of live sod; yields ranged from 140 kg/ha with 112 kg/ha N on live sod to 9,980 kg/ha with 448 kg/ha N on killed sod. The excellent yields from corn in grass sod show that corn can be grown on the sloping fields of the Piedmont and related areas to fill the grain needs there without causing serious soil erosion.
Role of Pensacola Bahiagrass Stolon‐Root System in Fertilizer Nitrogen Utilization on Leon Fine Sand1
Authors: Blue W. G. 
Published: July 2010

AbstractAn experiment was conducted with Pensacola bahiagrass (Paspalum notatum Flugge) on Leon fine sand near Gainesville, Fla. for 6 years to determine residual effects of applied N on forage N uptake, and changes in stolons, roots, and soil N. Nitrogen was applied at 0, 112, 224, and 448 kg/ha/year. Except for the control, paired plots were used at each N rate. Nitrogen fertilization was dis. continued on one of each treatment pairs in 1969 and 1970 to determine the residual effect of N. These treatments were resumed in I971. The residual effect of N was small for all treatments, amounting to 8, 41, and 95 kg/ha total N in harvested forage above the control for the 2‐year period for the 112, 224, and 448 kg N rates, respectively. Unrecovered N through 1968 was approximately 200, 350, and 770 kg/ha for the three treatments, respectively. Nitrogen lost from the stolon root systems during 1969 and 1970 through decrease in mass and N concentrations was 60, 100, and 190 kg/ha for the three N treatments, respectively. Little of the unrecovered N could be accounted for by analysis of the surface soil. Lack of residual effect on plant growth confirmed that little available N was in the soil profile to rooting depth. Based on previous studies, leaching appears to have limited importance when N is applied to well‐established perennial grass pastures during the growing season. Conditions imposed in this soil by high water table, large amounts of plant residues, and rapid decomposition during the summer season could make denitrification a significant factor.
Increase in Conductivity of Irrigation Water during Sprinkling1
Authors: Robinson Frank E. 
Published: July 2010

AbstractThe test was conducted on a high evaporative demand July day to evaluate the possible harm that could result from concentration of salinity as water is sprinkled in an arid desert area.Catchment beakers (250 ml) were set at 19‐m intervals across a 190‐ × 219‐m alfalfa (Medicago sativa L.) field that was sprinkled for 19.5 hours. Conductivity of the sprinkler water increased 21% on the field edge and 4.4% inside the field.
Water‐Use Efficiency and Its Relation to Crop Canopy Area, Stomatal Regulation, and Root Distribution1
Authors: Teare I. D. , Kanemasu E. T. , Powers W. L. , Jacobs H. S. 
Published: July 2010

AbstractThe differences in water‐use efficiency between sorghum [Sorghum bicolor (L.) Moench] and soybean [Glycine max (L.) Merrill] were compared in terms of leaf area index (LAI), size of root system, canopy stomatal resistance (R̄c), net assimilation rate (NAR), and evapotranspiration (ET). The field water budget was measured by recording the rainfall, and irrigation water applied in relation to the ET as measured with two weighing lysimeters.The evapotranspiration rates of the two crops began to diverge about August 15. This was the period when the soybean canopy began to close and the soybean LAI increased to about 1.5 times that of sorghum. NAR for sorghum during stalk elongation and heading (Aug. 15) was nearly four times that of soybeans during that time.Divergence of the two evapotranspiration curves coincided with observed differences in canopy stomatal resistance. In August after a stress period, the R̄c for sorghum at 1 and 3 pm was nearly three times the R̄c for soybeans. The increase in R̄c for sorghum was concommitant with an air temperature increase of 3 C above the air temperature near soybeans.Sorghum had approximately twice the weight of roots per volume of soil as soybeans. Even though atmospheric demand for H2O was similar for the two crops, sorghum was able to close its stomata more than soybeans, and thus conserve soil water even with a larger root system and more water in the soil profile resulting from reduced evapotranspiration.Water‐use efficiency of sorghum (gm DM/kg H2O) was approximately three times that of soybeans on dry matter or grain yield bases.
Ionic Balance for Barley as Influenced by P Fertility, Water, and Soil Temperature1
Authors: Follett Ronald F. , Reichman George A. 
Published: July 2010

AbstractThe relationship between organic anion concentration and yield of spring barley (Hordeum vulgate L., var. ‘Sacramento’) was investigated in a growth room at three levels of P. This relationship was tested at three levels of available soil water (W) and three soil temperatures (T). The concentration of organic anions was determined as the difference between the sum of the meq/kg of inorganic cations (Na+, K+, Ca2+, Mg2+) and the sum of the meq/kg of inorganic anions (CI‐, NO3−, H2PO4−, and SO42−). A normal organic anion (C‐A) concentration was considered to be that giving optimal growth. In this study, P was more important for obtaining a normal (CA) than either W or T. Phosphorus increased yields, decreased (C‐A) to near normal, and decreased the adverse effects of low W and low T. The large differences in (C‐A) between treatments suggests that, under adverse conditions, organic anions may serve as reservoirs of useful metabolites. Nitrate in the total plant tops, expressed as a percent of the total‐N (N/T), was associated with 82% of the yield variance for treatments yielding less than 11 g/can. For treatments yielding more than 11 g/can, the average value for (N/T) was 0.88%. Potassium accounted for over 55% of the inorganic cation charge and appeared to be the major form for both organic and inorganic salts. Changes in soil pH resulted from nutrient uptake, with 61% of the variance of the change in [H+] associated with the difference between inorganic anion uptake and inorganic cation uptake.
Zinc Response of Maize (Zea mays L.) Grown on Sandy Inceptisols in Western Nigeria1
Authors: Osiname O. A. , Kang B. T. , Schulte E. E. , Corey R. B. 
Published: July 2010

AbstractField experiments were conducted with IITA maize (Zea mays L.) composite B at six locations ranging from forest to savannah in the Western State of Nigeria to assess the level of zinc response on sandy Inceptisols. Zinc, as Na2 Zn EDTA, was applied as broadcast application at 0, 1.0, 2.0, 4.0, and 8.0 kg/ha. Zinc response in terms of growth development and grain yield was limited to the savannah where yield increases of 1,747 kg/ha of grain were obtained with application of Zn at 1 to 2 kg/ha.For optimum grain yield, 12 ppm Zn in tissue appeared minimal. Maize response to Zn application was most probable when the 0.1N HCl soil‐extractable Zn was less than 1.0 ppm when measured at silking time.
Increased Yield and Persistence of Red Clover after a Soil Drench Application of Benomyl1
Authors: Leath K. T. , Zeiders K. E. , Byers R. A. 
Published: July 2010

AbstractBenomyl (methyl 1‐[butylcarbamoyl]‐2‐benzimidazolecarbamate) fungicide was applied as a soil drench to red clover (Trifolium pratense L.) field plots in June 1970, the second growing season. Forage yields from the benomyl‐treatcd plots were significantly higher than yields from the untreated plots in 1970 and 1971. In September 1971, benomyl‐treated plots had more plants, many of which were large and were classified as original plants; more root borers (Hylastinus obscurus [Marsham] per plant; and fewer weeds than did the untreated plots. Fusarium was the only pathogenic fungus consistently isolated from rotted roots in September 1971.
Weanling Meadow Vole Responses to Crownvetch Forage1
Authors: Shenk J. S. , Risius M. L. , Barnes R. F. 
Published: July 2010

AbstractCrownvetch (Coronilla varia L.) has been reported to contain antiquality constituents. Feeding trials were conducted to determine the feasibility of using the weanling meadow vole (Microtus pennsylvanicus) as a bioassay to assess the effects of these antiquality constituents on feed intake, body‐weight change, and ration digestibility. The feeding value of crownvetch forage was compared with that of alfalfa (Medicago sativa L.), birdsfoot trefoil (Lotus corniculatus L.), and sainfoin (Onobrychis viciaefolia Scop.) incorporated at 15% dry weight into a nutritionally adequate and balanced diet. Voles had lower intake and lost weight when fed crownvetch than when fed the other legume forages. No relationship existed between intake or weight loss and apparent digestibility. However, not all crownvetch forages resulted in lower intake and weight loss, and samples differed in their capacity to cause adverse vole responses from year to year. Voles also differed in their responses to forage fed from individual plants of the ‘Chemung’ cultivar. Low intake appeared to be the primary reason for the weight loss and death which occurred on many samples. The information presented indicates the presence of an antiquality constituent(s) in crownvetch forage that should be thoroughly investigated for its effects upon other animal species, especially rapidly growing monogastrics.
Variability of Fraction 1 Protein and Heritability Estimates for Fraction 1 Protein and Total Phenolic Constituents in Alfalfa1
Authors: Miltimore J. E. , McArthur J. M. , Goplen B. P. , Majak W. , Howarth R. E. 
Published: July 2010

AbstractThe primary cause of lethal alfalfa pasture bloat is Fraction 1 Protein (FR1P) and bloat occurs when FR1P is above 1.8%. Before starting a selection or breeding program to develop a nonbloating alfalfa (Medicago sp.), it would be important to know the heritability and the range of FR1P levels in alfalfa plants. Accordingly, this investigation was undertaken with the objectives of determining the distribution of FR1P levels and the heritability of FR1P and total phenolic constituents in alfalfa clones. Sampling was undertaken at the prebud to bud stage of maturity. The top 15 cm of the plants were harvested.Fraction 1 Protein levels were obtained for 1,372 alfalfa plants of diverse origin. Only four plants, 0.3%, were below the bloat threshold of 1.8% in FR1P concentration on an oven dry weight basis. The average concentration for all alfalfa plants was 4.3%. M. sativa was generally higher in FR1P than other Medicago species. The lowest mean FR1P concentration, 3.1%, was found in M. hemicycla and M. glutinosa.A broad sense heritability estimate for FR1P was determined from a replicated nursery of 60 clones. With single plants from four replications in the first year, the heritability of FR1P was 28%. Heritability of total phenolic constituents in the first year using data from four replications was 16%. The correlation coefficient between years for FR1P was r = 0.40, 58 df. Cultivar differences in FR1P, observed in the first year, disappeared the second year when soil fertility level was increased. The mean FR1P level in the second year was 4.8%.
Estimation of Leaf Area in Grain Sorghum from Single Leaf Measurements1
Authors: Krishnamurthy K. , Jagannath M. K. , Rajashekara B. G. , Raghunatha G. 
Published: July 2010

AbstractStudies were made to examine the applicability of a common leaf product constant (K‐constant × length × width), for estimating the area of single leaf and it was found that the same constant was applicable for the 3 sorghum genotypes (Sorghum bicolor L Moench) studied (K=0.71). Adaptability of the common leaf product constant for individual leaves according to its position in the plant was also tested by regression analysis, and the same constant was found to be applicable in most cases.Because complete measurement of all leaves of a plant in field trials is time‐consuming and involves prohibitive labor input, the most representative leaf was identified through correlation studies to use it in working out the leaf area index. The largest leaf was found to be the most representative. This representative leaf differed with genotype, depending upon total leaf number. An appropriate factor to work out leaf area of the whole plant from a single leaf was determined. This leaf area factor was found to vary from 4.106 to 5.873 among the sorghum genotypes.
Phosphate Uptake Rate of Corn Roots as Related to the Proportion of the Roots Exposed to Phosphate1
Authors: Jungk A. , Barber S. A. 
Published: July 2010

AbstractLittle information is available on the effect of reducing the proportion of a plants roots in contact with P on the rate of P uptake by those roots. Three experiments were conducted with corn (Zea mays L.) in solution culture in a growth chamber. In the first experiment trimming roots to reduce root length per plant gave results on P uptake similar to using a split‐root system where a portion of the roots were in a nutrient solution containing 50 μM P. Uptake of P over an 8‐hour or shorter period was in proportion to the length of root exposed to the P solution. Hence, phosphorus uptake rate per unit of root was not increased by reducing the proportion of the root in contact with P. In an experiment conducted over a 4‐day period, with P levels of 100 and 1000 μM, an increase of 20 to 40% P uptake per unit of root occurred when root length was reduced to 37 to 58% by trimming. A lower P level in the plants with trimmed roots as compared to those with untrimmed roots may have caused the increase in P uptake rate per meter of root. In a 4‐hour experiment with P concentrations between 5 and 10 μM, trimming the roots did not increase the P uptake rate per unit of root length. The results indicate that it is necessary to supply P to a large proportion of the roots in order to adequately supply the plant.
Relation of Foliar Disease of Quality of Alfalfa Forage1
Authors: Leath K. T. , Shenk J. S. , Barnes R. F. 
Published: July 2010

AbstractA method is needed to detect the effects of foliar diseases on forages in order to determine whether the feeding of diseased forages to animals is potentially dangerous. To obviate some of the difficulties of largeanimal feeding trials, we used the meadow vole (Microtus pennsylvanicus) to assay for anti‐quality components in diseased alfalfa (Medicago sativa L.) produced in the greenhouse. The forage was inoculated sequentially with each of five foliar pathogens and compared with healthy forage for chemical composition, in vitro dry matter disappearance (IVDMD), and weanling meadow vole responses. Foliar disease did not significantly alter chemical composition, IVDMD of the forage, or dry matter digested by weanling voles fed these forages at 60% of their diet. Intake of alfalfa diseased with Uromyces striatus Schroet. was significantly greater than that of the healthy forage and intake of alfalfa diseased with Stemphylium botryosum Wllr. was significantly lower. Weight gains were significantly lower for voles fed alfalfa diseased with Phoma medicaginis Malbr. and Roum. and S. botryosum. Neither intake nor weight gain was affected by forage diseased with Leptosphaerulina briosiana (Poll.) Graham and Luttrell or Pseudopeziza medicaginis (Lib.) Sacc.