bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphorus Placement for the Establishment of Alfalfa and Bromegrass1
Authors: Sheard R. W. , Bradshaw G. J. , Massey D. Lawrence 
Published: July 2010

AbstractEfficient production of forage species is greatly hindered by inadequate stands. The results from a greenhouse and two field experiments using 32P‐labeled, monocalcium phosphate showed increased P uptake from fertilizer placed five cm directly below surface sown seed of alfalfa (Medicago sativa L.) or bromegrass (Bromus insrmis L.). Dispersing the P throughout the soil volume, localizing the P on the soil surface, or moving the band laterally from a position directly below the seed, all decreased fertilizer P uptake, and as a result reduced the weight of individual seedlings of both species from that obtained where the fertilizer P was placed directly below the seed.Fifteen days after seeding, alfalfa and bromegrass seedlings emerging directly over the fertilizer band obtained 50 to 56% of their P content from the fertilizer. Only 2.5 to 6.5% of total P was obtained from the fertilizer where the band was located 3 cm laterally, and none from bands located at a 6 or 9 cm lateral displacement. The root system of the two species did not reach the 9 cm band until 29 days after planting. Fifty days after planting, 10 to 14% of the P was derived from the fertilizer band in plants grown with a 9‐cm lateral displacement of the fertilizer band, in contrast to half the P absorbed from the fertilizer by plants grown directly over the fertilizer band.The increased utilization of fertilizer P by both grass and legume species at a very early stage in growth when the fertilizer is banded directly below the seed will result in more vigorous seedlings, and greatly reduce the hazards of forage establishment.
Effect of N Fertilization and Simazine on Yield, Protein, Amino‐acid Content, and Carotenoid Pigments of Coastal Bermudagrass1
Authors: Monson Warren G. , Burton Glenn W. , Wilkinson W. S. , Dumford S. W. 
Published: July 2010

AbstractReports of increased protein levels in several plant species with simazine treatments prompted this study of the response of coastal bermudagrass (Cynodon dactylon L. Pers.) to simazine. Simazine was applied at rates ranging from 0 to 4.5 kg/ha on an old sod of coastal bermudagrass. Additional variables were N fertilization (56 to 672 kg/ha) and cutting frequency (3 and 6 weeks). Nitrogen fertilization and cutting frequency significantly affected yields of dry matter and protein. Simazine applications had no effect on dry‐matter yield, protein yield, or protein percentage. Carotene and xanthophyll contents of the grass increased with an increase in N fertilization from 336 to 672 kg/ha. Carotene content of the grass tended to increase due to simazine treatment with 360 kg/ha N and to decrease with 672 kg/ha. Samples were analyzed for 15 amino acids, and differences between the amino‐acid profile of the protein from check and simazine‐treated samples suggested that simazine may alter amino acid composition of protein.
Profile Modification and Root Yield, Distribution, and Activity1
Authors: Eck Harold V. , Davis Ronald G. 
Published: July 2010

AbstractDeep plowing or other profile medication of a soil may alter root yield and distribution. Root systems of plants grown on soil rotary tilled 20 cm deep; plowed 90 cm deep; and plowed 90 cm deep with 22,400 kg/ha of Na2CO3 were sampled to (i) determine effects of treatments on yield and distribution of roots, and (ii) examine relationships between root yields and root activity as indicated by top‐root ratios and Sr85 uptake.Deep plowing tended to decrease root yields of sudangrass (Sorghum sudanense), sugarbeets, (Beta vulgaris), and soybeans (Glycine max) but had little effect on those of cabbage (Brassica oleracea var. ‘capitata’). Root yields decreased with depth on soil rototilled to 20 cm or moldboard plowed to 90 cm, but roots tended to be evenly distributed throughout the 90 cm profile when 22,400 kg/ha of Na2CO3 was applied at the 90‐cm plow depth.Root activity, as measured by top‐root ratios, was enhanced by profile modification. Top‐root ratios are shown to be better indicators of root activity than top or root yields alone.Sr85 uptake data indicated that roots in the 70‐ to 90‐cm zone were as active as those in the O‐ to 20‐cm zone. Na2CO3 tended to increase root weights in its zone of application but reduced radiostrontium uptake about eightfold compared with uptake from similarly placed radiostrontium without Na2CO3, indicating a Na2CO3‐induced decrease in root activity.
Temperature Influence on Herbicide Injury to Navy Beans1
Authors: Penner Donald , Graves Dennis 
Published: July 2010

AbstractInjury to navy bean (Phaseolus vulgaris L.) by 2‐chloro‐2',6'‐diethyl‐N‐(methoxymethyl) acetanilide (alachlor) was observed at 20 and 25 C but not at 30 C. This injury was observed in the ‘Sanilac,’ ‘Seafarer,’ and ‘Gratiot’ varieties but not in the ‘Michelite’ variety. The herbicides S‐ethyl dipropylthiocarbamate (EPTC) and α,α,α‐trifluoro‐2,6‐dinitro‐N,N‐dipropyl‐p‐toluidine (trifluralin) did not injure the navy beans at 20, 25, or 30 C under the controlled environment of the experiment at rates up to twice the 3.37 and 0.85 kg/ha rates, respectively, used in the field. Navy beans were injured at all temperatures studied, 20 C, 25 C, and 30 C, by 3‐(3,4‐dichlorophenyl)‐ l‐methoxy‐l‐methylurea (linuron) at three‐fourths the rate used for weed control in soybeans [Glycine max (L.) Merr.].
Dieldrin and Heptachlor Residues in Soybeans1
Authors: Turner B. C. , Taylor A. W. , Edwards W. M. 
Published: July 2010

AbstractWhere soybeans [Glycine max (L.) Merr.] are grown on land previously planted to maize (Zea mays L,.), the soybean crop may be contaminated with residues of organochlorine insecticides applied to the soil for control of soil‐borne predators attacking maize. Experimental findings on the decrease of contamination with time are meagre. In 1970, soybeans were grown on experimental fields that had received 5 kg/h of dieldrin, mixed to the 7.5‐cm depth in 1970, 69, 68, 67, and 66. Residues in the soybeans declined rapidly over the first 2 years after application, but showed little further change in the 3rd through the 5th year. At harvest, beans from the lower half of the plant contained 0.31 ppm from the 1970, 0.132 ppm from the 1969, and 0.038 ppm from the 1968 applications. Beans from the upper half contained ½ to ¼ of these amounts. Heptachlor residues, principally heptachlor epoxide, from a parallel treatment in 1969 were less than the dieldrin. The data confirm that soybeans should not be planted for 2 years after soil has been treated with dieldrin.
Effects of Low Levels of Atrazine on Some Mineral Constituents and Forms of Nitrogen in Zea mays L.1
Authors: Hiranpradit H. , Foy C. L. , Shear G. M. 
Published: July 2010

AbstractSublethal concentrations of s‐triazine herbicides are known to increase the protein in plants. Conceivably, the effect may be related to increased nutrient accumulation or to stimulation of enzymes involved in nitrate reduction and/or carbohydrate utilization for amino acid and protein synthesis. A study was undertaken to determine the effects of subtoxic levels of atrazine (2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine) on the mineral constituents, forms of N, and growth of 28‐day‐old corn (Zea mays L. ‘Cribfiller’) plantsCorn was grown in soil containing various levels of atrazine under greenhouse conditions and analyzed after 28 days. Atrazine at 1.5 ppm (7.0 µM) concentration did not significantly affect plant dry weight, but significantly increased percentages of N and K compared with untreated controls. Total amounts of N, P, K, and Ca per plant were significantly increased over the untreated controls by 18.9, 14.9, 16.4, and 13.8%, respectively. The treated plants contained significantly more nitrate‐N, protein‐N + nucleic acid‐N, and chlorophyll‐N + lipid‐N than the untreated controls. The increases were 14.2, 39.0, and 31.2%, respectively. Total amounts of acid soluble‐N and ammonium‐N were not significantly increased. Overall, there was an increase in amino acids that form the constituents common to nearly all protein, molecules.
Effects of Low Levels of Bromacil on Some Mineral Constituents and Forms of Nitrogen in Glycine max (L.) Merrill1
Authors: Hiranpradit H. , Foy C. L. , Shear G. M. 
Published: July 2010

AbstractCertain s‐triazine herbicides are known to increase the protein in plants perhaps by enhancing nutrient accumulation and/or affecting enzymatic conversion in N and carbohydrate metabolism. Conceivably, other proven inhibitors of photosynthesis could have similar effects. The present study was conducted to determine the effects of subtoxic levels of bromacil (5‐bromo.3‐sec‐butyl‐6‐methyluracil) on the mineral constituents, forms of N, and growth of 28‐day‐old soybean [Glycine max (L.) Merrill. ‘Lee’] plants.Soybeans were grown in soil containing various levels of bromacil under greenhouse conditions and analyzed after 28 days. Bromacil at 0.0225 ppm (0.086 µM) concentration did not significantly affect plant dry weight but significantly increased both percentages and total amounts of N and P in plant shoots compared with untreated controls. The increases in total amounts of N and P per plant were up to 15.0 and 15.6% more than the untreated controls. The treated plants took up about 18% more nitrate‐N than the untreated controls, which resulted in significantly higher accumulation of protein‐N + nudeic acid‐N in the plants. Total amounts per plant of acid soluble‐N and ammonium‐N also tended to be increased. Overall, there was also an increase in amino acids that form the constituents common to nearly all protein molecules.
Effectiveness of Resistance in Maize to Maize Dwarf Mosaic1
Authors: Scott Gene E. , Nelson Lloyd R. 
Published: July 2010

AbstractOur objectives were to determine the effect of maize dwarf mosaic (MDM) on the performance of corn (Zea mays L.) hybrids as well as to determine the effectiveness of resistance in preventing yield losses. Diallel crosses among corn inbred lines known to be resistant or susceptible to maize dwarf mosaic were grown in field experiments. Paired‐row plots of each hybrid were grown and one row was inoculated with the maize dwarf mosaic virus (MDMV). Comparisons were made between the inoculated and noninoculated rows for percentage of diseased plants, plant height, yield (g/pl), ears/100 plants, weight/500 kernels, and days to midsilk. Crosses between inbreds known to be resistant were not materially affected by MDM and, thus, were effective in preventing yield losses by this disease. This disease, however, reduced grain yield on both the resistant ✕ susceptible and susceptible × susceptible crosses. Plant height and number of ears per 100 plants were also reduced by MDM in these same crosses. Plots of susceptible hybrids that were inoculated required more time to reach the midsilk stage of growth than noninoculated plots.
Agronomic Response of Three Height Classes of Spring Wheat, Triticum aestivum L., Compared at Different Yield Levels1
Authors: McNeal F. H. , Berg M. A. , Stewart V. R. , Baldridge D. E. 
Published: July 2010

Abstract‘Centana’ (Cnt) plus short, medium, and tall selections of Norm 10/Brevor, 14//6*Centana were grown in yield nurseries at 22 Montana locations in 1969 and 17 locations in 1970. The study was designed to determine the magnitude of the genotype by environment interactions of the three height classes when grown under Montana conditions. Such information is needed to help define the limitations, if any, of semidwarf spring wheats. Agronomic data from each location are reported within one of six yield levels, each level separated by 673 kg/ha (10 bu/acre), with the location average yield determining the yield level assigned.Medium Cnt had the highest grain yield at all yield levels, except at one location which yielded less than 1352 kg/ha (20 bu/acre). Short Cnt was consistently lowest of the four entries in grain yield and test weight. Short Cnt increased only 29.3% in plant height from the second to sixth yield level, whereas other varieties increased more than 48%. The grain:straw ratio was highest for short Cnt and lowest for Centana and tall Cnt.The data suggest that breeding efforts for Montana spring wheat should emphasize the development of single gene dwarfs (semidwarfs), and that 2‐gene dwarfs (short selections) generally should be avoided.
Fixation and Excretion of Nitrogen by Tropical Legumes1
Authors: Agboola Akinola A. , Fayemi Adeboyejo A. A. 
Published: July 2010

AbstractSince earlier investigations revealed that interplanted legumes competed with a late crop of corn (Zea mays L.) and suggested that legumes were incapable of benefiting associated nonlegumes over the same growing period, relatively short‐season legumes, calopo (Calopogonium mucunoides), cowpea (Vigna sinensis), and greengram (Phaseolus aureus), were interplanted with corn in the early cropping season to measure their effects on both the early planted and the late‐planted corn crops.Two days after harvesting the intercrops of corn and legumes, soil samples from the 0‐ to 15‐ and 15‐ to 30‐cm depths were collected from the unfertilized plots of control (no legume), cowpea, greengram, and calopo in order to determine in the greenhouse the soil N status. Two other greenhouse experiments were conducted to check the N‐fixing and N‐excreting ability of the legumes.The investigations showed that calopo, cowpea, and greengram fixed N when planted alone and when interplanted with corn. Cowpea and calopo interplanted with corn did not benefit the early corn crop, but as green manure they were an important source of N for the corn in the late‐cropping season. On the other hand, greengram interplanted with corn in the early season increased yield of the early corn crop but contributed very little to the yield of the late corn crop.The data also revealed that tropical legumes are capable of fixing large quantities of N under improved conditions. Calopo, cowpea, and greengram fixed equivalents of 450, 354, and 324 kg/ha, respectively, when inoculated and grown in a complete nutrient culture (except for N) as compared to 370, 157, and 63 kg/ha, respectively, when not inoculated and grown in unfertilized soil.
Influence of Soil Temperature on the Geotropic Response of Corn Roots (Zea mays L.)1
Authors: Mosher P. N. , Miller M. H. 
Published: July 2010

AbstractExperiments were conducted in controlled temperature cabinets to determine the factor that caused corn (Zea may L.) radicles to grow nearly straight down from the seed in a greenhouse experiment conducted during the summer, and horizontally in a second experiment conducted during the winter.The possibility of horizontal growth caused by atrazine residues in the soil of the second experiment was eliminated when this type of growth was observed in vermiculite as well. Nearly vertical growth was observed when radiant energy from a heat lamp was directed onto the soil surface. The possibility that the roots followed a temperature gradient was eliminated by demonstrating vertical growth toward as well as away from the radiant energy. The soil temperature at the seed was found to be the primary factor involved. The angle of radicle growth varied from 30° from the horizontal at 18 C to 61° from the horizontal at 36 C.The influence of soil temperature on the direction of radicle growth explains many observations on root growth from the literature. It appears that the direction of growth of the radicle as well as that of the seminal and nodal roots is controlled by soil temperature.
Relationship of pH to Ion Uptake Imbalance by Varieties of Wheat (Triticum vulgare)1
Authors: Dodge C. S. , Hiatt A. J. 
Published: July 2010

AbstractVarietal differences in plant‐induced pH changes have been considered a possible factor in Al tolerance. The objective of this study was to determine the magnitude of plant‐induced pH changes by wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) and to determine the cause of observed varietal differences. Varieties of wheat or barley differed considerably in their effect on the pH Level of complete nutrient solutions. Ion uptake and H+ transfer between plants of three varieties of wheat and KNO3‐Ca(NO3)2 solutions were measured to determine the reason for varietal differences in plant‐induced pH shifts. Changes in nutrient solution pH were attributable to differences in anion and cation absorption. Consequently, varietal differences in effect on solution pH levels were accounted for by varietal differences in anionminus‐cation uptake (A‐C) values.Nutrient solutions from which anions had been absorbed in excess of cations were highly buffered. This buffering capacity was lost when the solutions were acidified and aerated, suggesting that HCO‐3 exchanged for the excess anions.Plant‐induced changes in nutrient solution pH varied with the form of N in the solution. When NO3‐ was the only form of N present, pH levels consistently increased from the initial level. However, solution pH decreased when NH4+ was present in quantities as low as 0.5% of the total N.
Apparent Induction of Nitrate Uptake in Nitrate‐depleted Plants1
Authors: Jackson W. A. , Volk R. J. , Tucker T. C. 
Published: July 2010

AbstractPrevious investigations revealed that nitrogen‐depleted wheat absorbed nitrate slowly on first exposure to nitrate solutions. Subsequently, however, the rate of nitrate uptake increased. The present studies were initiated to more thoroughly characterize this response in wheat, and to determine if other species responded similarly. Nitrate uptake of various species was determined from changes in the amount of nitrate in the external solution. Both chemical and isotopic procedures were employed. With nitrogen‐depleted wheat, the characteristic two‐phase pattern was observed even when nitrate uptake was severely restricted by presence of ammonium. Chloride uptake differed from nitrate uptake in two ways; the initial slow phase was not observed and the tissue reached chloride flux equilibrium at about six hours. Corn seedlings previously grown with ammonium showed the two phase pattern of nitrate uptake whereas linear rates were observed when they were previously grown with nitrate. After being deprived of nitrate, cotton and tobacco both exhibited the two‐phase pattern of nitrate uptake.
Influence of Nitrogen Fertilizer on Stands, Yields of Herbage and Protein, and Nitrogenous Fractions of Field‐grown Alfalfa1
Authors: Lee Chin‐tian , Smith Dale 
Published: July 2010

AbstractStudies of fertilizing alfalfa (Medicago sativa L.) with N were initiated because of the possibility of increasing protein yields since there is current interest in the leaves or herbage as a sourc of a concentrated protein for human and animal consumption. Two N fertilization trials were conducted at Arlington, Wis., on established stands.The first experiment was conducted during 1968 with a 2‐year‐old stand of ‘Vernal’ alfalfa. Six N treatments (0, 56, 112, 224, 448, and 896 kg/ha of N as NH4NO3) were initiated in April and repeated in separate areas after the first harvest and after the second harvest. Each harvest was made at first flower. N had no significant effect on stands, herbage yields, or herbage total nonstructural carbohydrate percentages. N significantly increased protein yields only in the third harvest. Percentages of total‐, non‐protein‐, nitrate‐, free α‐amino‐, asparagine‐, and glutamine‐N in leaflets, stems, and total herbage were increased with each increase in N rate, but percentage of ammonium N was not affected. Protein percentages in leaflets were not affected by N rates, but they increased slightly in both the stems and total herbage as N rate increased.A second experiment was conducted during 1969 and 1970, in the same field of alfalfa as in 1968, when all N treatments had 336 kg/ha of N applied annually in various ways. Treatments were (1) no N; (2) all N applied in the spring, (3) after the first harvest, or (4) after the second harvest; (5) half the N applied in the spring and half after the first harvest, or (6) after the first and second harvests. All harvests were made at first flower. Stands were not affected by the treatments. N treatments significantly increased the total seasonal herbage and protein yields in both years, with a few exceptions in 1969 for protein. However, there was no significant difference among the N treatments that significantly increased yields. The average yield increase over the control amounted to only 6.1% for herbage and 12.2% for protein in 1969, and 16.0% for both herbage and protein in 1970.
Experimental Curves and Rates of Change from Piecewise Parabolic Fits1
Authors: DuChateau P. C. , Nofziger D. L. , Ahuja L. R. , Swartzendruber D. 
Published: July 2010

AbstractThe determination of experimental curves and rates of change for nonlinear data is approached and solved without assuming an artificially restrictive mathematical form for the complete range of the data. This relatively form‐free result is achieved by least‐squares computer fitting of parabolic segments to short subranges of the experimental data. Two ways of doing this, referred to as the sliding‐parabola and the parabolic‐splines methods, are developed. These are tested on both smooth and scattered data generated basically from the function y = x1/2, without and with random error, respectively. for smooth data the sliding‐parabola method is slightly better than the parabolic splines, but in general both are subject to only very small errors, and are also in good agreement with a previously presented graphical prism method. For scattered data wherein the inherent errors of function and slope evaluation are much increased, the parabolic‐splines method is distinctly superior to the sliding parabola method. Both methods require only relatively short computing times, on the order of 1 sec for 40 data points, and are of utility for determining nonconstant experimental rates of change and for least‐squares curve fitting without specification of a complete‐range mathematical curve.
Effect of the Soil and Plant Water Potentials on the Dry Matter Production of Snap Beans1
Authors: Millar A. A. , Gardner W. R. 
Published: July 2010

AbstractThe need for greater plant yields and more efficient use of water makes it essential that the relations between soil‐water content, soil‐water potential, transpiration rate, and plant response be made ever more quantitative.The dry matter production rate of snap beans (Phaseolus vulgaris L., var. Bush Blue Lake) growing under field conditions on a sandy soil is analyzed during a drying period.Measurements of plant‐ and soil‐water potentials, dry matter accumulation, and stomatal resistance were made as soil‐water was depleted, while the transpiration rates were obtained by a model for a loosely structured canopy.The transpiration and dry matter production rates decreased curvilinearly with soil‐water potential. When the soil‐water potential decreased from −0.28 to −0.40 bar, there was 47% reduction in the dry matter production rate. This is related to the turgor pressure‐operated stomatal mechanism. The adaxial stomatal resistances increased at leaf‐water potentials lower than −8 bars, which coincided with a rapid decrease in the dry matter production rate. It was found that stomatal closure due to water stress resulted in a greater reduction of growth rate than in transpiration.