bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the Sulfur Status of Field‐Grown Wheat by Plant Analysis1
Authors: Spencer K. , Freney J. R. 
Published: July 2010

AbstractDiagnostic methods developed under laboratory or greenhouse conditions require field confirmation. This paper reports the relative field performance of four indexes for the diagnosis of S deficiency in wheat (Triticum aestivum L.) which were previously assessed in the greenhouse. Sulfate S (as percent total S), sulfate S concentration (as ppm dry matter), total S concentration (as ppm dry matter), and total N: total S ratio in the aboveground parts of a soft white wheat cultivar, ‘Olympic’, were compared as diagnostic indexes in a factorial experiment with five rates of gypsum (0 to 50 kg S/ha) and three rates of ammonium nitrate (0 to 100 kg N/ha). A strong relationship was found between final grain yield and each index at the following stages of growth; fourth leaf (61 days from sowing), fully‐tillered (92 days), and jointing (134 days). However, as the critical value for sulfate S (as percent total S) was least affected by the age of the plant or N supply, it is considered to be the most convenient index. The overall relationship between yield and sulfate S (as percent total S) was strong (r = 0.88) and the critical value at 90% of maximum yield was 13%. This compares with r values of 0.87, 0.96, and 0.91 and critical values of 14, 12, and 11% for the plant tissue at the individual growth stages examined. Where the adequacy of the S supply to a wheat crop is in question, the proportion of total S as sulfate S in the plants is indicated as a useful guide to the need for S fertilizer in securing optimal grain yield.
Survival of Rhizobium phaseoli in Contact with Chemical Seed Protectants1
Authors: Graham P. H. , Ocampo G. , Ruiz L. D. , Duque A. 
Published: July 2010

abstractIn the multiple cropping systems used for bean (Phaseolus vulgaris L.) production in Latin America, seed treatment is often needed for control of soil pathogens and pests, but can be incompatible with Rhizobium inoculation. This study looks at the interaction between Rhizobium and seed protectant. One laboratory and three field studies are reported. The survival of R. phaseoli on bean seeds treated with PCNB, thiram, or captan was measured under laboratory conditions using standard serial dilution and plate count techniques. At Popayan, Colombia (typic dristandept, pH 4.8) the nodulation and nodule development of bean seeds treated with PCNB, thiram, captan, and furadan was evaluated, and different inoculation methods, including a granular soil applied inoculant, compared. Nodulation of beans protected with PCNB or thiram, and inoculated with seed or soil‐applied rhizobia was also studied at La Selva, Colombia (typic dristandept, pH 5.1).While contact with PCNB, thiram or captan on seeds reduced Rhizobium survival, with captan most toxic, PCNB‐treated seeds maintained counts of l03 rhizobia/g seed until almost 48 hours after inoculation. Field results demonstrated the delicate balance between inoculant and seed protectant. At Popayan, nodule number/plant was not affected when thiram, furadan, or PCNB‐treated seeds were inoculated and promptly planted, but delay between inoculation and planting did reduce the nodulation of seeds protected with PCNB or thiram. At La Selva, all fungcide treatments lowered nodule number/plant. Seed protection with PCNB enhanced nodule development at Popayan and reduced root rot incidence at La Selva. Despite the somewhat acid soil conditions the best nodulation at both Popayan and La Selva was attained with granular soil‐applied inoculants. Further studies on this method of inoculation for beans are warranted.
Soil Water Effects on No‐till Corn Production in Strip and Completely Killed Mulches1
Authors: Box J. E. , Wilkinson S. R. , Dawson R. N. , Kozachyn J. 
Published: July 2010

AbstractNo‐till row cropping in plant residue mulches can effectively eliminate the high erosion rates of clean tilled, rolling soils in the Southern Piedmont. This study was conducted to evaluate corn (Zea mays L.) production on two mulches with five soil water treatments and a uniform high fertility level. The statistical design was a randomized block with mulches as main plots and irrigation levels on the split plots. Each treatment was replicated three times. The mulch treatments were viable fescue sod with corn planted in the same 20‐cm strips of sod killed annually prior to planting (SK); and a completely killed mulch (CK) of fescue, or winter rye on the same plot area and in the sequence of fescue‐corn (1973) followed by winter rye‐corn (1974 and 1975). Soil water treatments were: rainfall only (M1), rainfall plus sprinkler irrigation when soil water potential in the 0‐30 cm soil depth averaged −10 (M2), −5 (M3), or −2 (M4) bars, and 5 cm/wk (M5). Corn received annually about 450 kg/ha N; P, K, and Mg additions were based on soil analysis. Both fescue and winter rye received 45 kg/ha each N, P, and K in the fall.Corn grain and stalk yields on the CK mulch were significantly higher than those on the SK mulch. Maximum grain yields occurred for both mulches on the M4 water treatment; stalk yields were largest on M2 M3, and M4, and depressed on M5. Winter and summer fescue forage yields were influenced by corn water treatments, but rye forage yields were not. Fescue stand count seemed to reach an equilibrium after the first full year, ranging from 30% after corn harvest to 60 percent before corn planting.Corn ear leaf nutrients which were within the sufficiency range for all treatments were N, P, Ca, Mg, Fe, Cu, Mn, and Zn. Potassium was marginal for SK treatments M1, M2, M3, and M4; however, although no visual plant deficiency symptoms were observed. Boron tissue concentrations were marginal for SK treatments M1, M2 and M3.Corn can be grown successfully either in annually strip‐killed fescue, or in completely killed mulch. Corn grain and stalk yields and total biomass production were consistently higher at all soil water levels for the CK mulch.
Crude Protein, IVOMD, and Yield of Stockpiled Limpograsses1
Authors: Quesenberry K. H. , Ocumpaugh W. R. 
Published: July 2010

AbstractMost tropical grasses show a marked decline in digestibility with age, thus a system of field stockpiling is not suitable. The purpose of this research was to investigate the use of three limpograss (Hemarthria altissima [Poir] Stapf. et C. E. Hubb) cultivars as autumn‐winter conserved forage. In 1976, plots of each cultivar were clipped and allowed to regrow from 1 July, 29 July, and 26 August. Six yield and quality harvests were taken at 6 week intervals beginning on 23 Sept. 1976. In 1977 all plots were clipped and allowed to regrow from 1 August with five harvest for yield and quality taken at 4‐week intervals beginning on 26 Sept. 1977. The yield results from 1976 suggest that stockpiling should begin by 1 August to allow for adequate dry matter accumulation by first freeze. ‘Redalta’ had higher yields than either ‘Greenalta’ or ‘Bigalta’ in both years, but dry matter accumulation patterns were similar for all grasses. In vitro organic matter digestion (IVOMD) of Bigalta was higher than Redalta or Greenalta at all sampling dates in both years. Regression analysis indicated a higher intercept and lower rate of decline in IVOMD of Bigalta than either Redalta or Greenalta.Log transformation of crude protein (CP) increased (P > 0.05) the fit over the linear model for all grasses. The decay in CP occurred rapidly in all grasses and by the time the grasses would be consumed as a stockpiled forage it had dropped below the level necessary to maintain zero N balance in the grazing animal. No meaningful differences in CP among grasses were observed. Our results suggest that Bigalta Limpograss has potential fot autumn‐winter stockpiling, but Redalta and Greenalta are probably not acceptable.
Effect of Leaf Age and Position on Photosynthesis and Stomatal Conductance of Forage Grasses1
Authors: Frank A. B. 
Published: July 2010

AbstractInformation on photosynthesis and stomatal conductance of different position leaves is needed to determine which leaf to sample for comparing rates of different grass species and genotypes. Photosynthesis and stomatal conductance were measured on the top three or four leaves on several dates after leaf collar formation on field‐grown accessions of pubescent wheatgrass [Agropyron intermedium var. trichophorum (Link) Halac.], crested wheatgrass [A. desertorum (Fisch. ex Link) Schult.], and reed canarygrass (Phalaris arundinacea L.). The study was conducted during 1976 and 1977 at Mandan, ND. Stomatal conductance was a primary factor affecting photosynthesis throughout the growing period. Leaf‐age effects were difficult to evaluate, but the data suggested a negligible effect of leaf age on photosynthesis for the three species studied. Leaf‐position effects were more evident for pubescent and crested wheatgrass than for reed canarygrass. There was no interaction between leaf position and genotypes within species. The uppermost leaves of each species studied had higher rates of photosynthesis at a given conductance when compared with lower position leaves.The study showed that, to compare genotypes within a species, relative photosynthetic rates of single leaves, can be determined from different leaf positions and from the time of leaf collar formation until leaf senescence, provided that these comparisons are made within each leaf position.
Water Consumption and Growth Rate of 11 Turfgrasses as Affected by Mowing Height, Irrigation Frequency, and Soil Moisture1
Authors: Biran I. , Bravdo B. , Bushkin‐Harav I. , Rawitz E. 
Published: July 2010

AbstractWater availability and cost is a limiting factor in the growth of turfgrass under warm semi‐arid zone conditions. Methods of reducing water consumption of turfgrasses in these zones are of major importance.Water consumption and dry matter yield of clippings were determined for 11 turfgrass species or cultivars, 2 of which were cool season and 9 warm‐season types. The former belong to the C‐3 and the latter to the C‐4 group. The plants were grown in containers under typical summer conditions of the warm, semi‐arid zone. The growth rate of plants in the C‐3 groups was similar to that of those in the C4 group but their water consumption was higher. Amongst the C‐4 group, those plants with a sparse, vertical, growth habit, typical of forage crops, had a higher growth rate and water consumption than the dense, low growing ones. A significant correlation coefficient (r = 0.71 at p<0.05), was found between water consump tion and growth rate for the C‐4 plants.Delaying irrigation until the onset of temporary wilting, caused a significant decrease in water consumption and growth (up to 35%) in most gasses. Raising the clipping height from 3 cm to 6 cm for a period of 6 weeks led to increased vigor in all grasses as evidenced by growth rate, chlorophyll content and water consumption. This effect was continuous throughout the measurement period for the C‐3 types, but was temporary for the C‐4 types, declining again after 6 weeks.In experiments carried out under constant 34.5 C temperature, net photosynthesis of tall fescue (Festuca arundinacea Schreb. ‘Alta’) (C‐3) was only about one‐third that of C4 grasses although the evapotranspiration rate was equally high. The water uptake of the C4 type Zoysia matrella (L.) Merr. ceased at a much higher soil water potential than that observed for the C‐3 tall fescue and other C‐4 types. The decline of the rate of photosynthesis preceded the decrease in transpiration rate caused by the decreasing soil water potential.The most important single factor affecting water use was the carbon fixation pathway to which the grasses belonged. Whilst the choice of a species or cultivar of turfgrass is generally made on the basis of temperature adaptation, should the criterion be water consumption in relation to availability and cost, then C‐3 varieties should not be chosen for warm semi‐arid zones to the extent that is practiced now.
The Effects of Different Soil Tillage and Management Practices on the Physical and Chemical Properties of Soil and Maize Yield in a Rainforest Zone of Western Nigeria
Authors: Agboola Akinola A. 
Published: July 2010

AbstractAfter World War I (1914–1918) a search for a permanent form of cultivation in Nigeria began. Among the methods tried were replacement of natural fallow with leguminous covercrops, planted grass fallow, and late minimum or zero tillage. With zero tillage, weed control and fertilizer application methods are problems that need immediate attention. An experiment conducted for 4 years employed the following eight treatments: (1) no tillage, no fertilizer; (ii) no tillage, fertilizer surface applied, herbicide applied; (iii) conventional tillage, fertilizer worked into the soil with implements; (iv) no tillage, fertilizer banded with hoe; (v) conventional tillage, fertilizer banded with hoe; (vi) herbicide, fertilizer banded with hoe; (vii) herbicide, no fertilizer; and (viii) herbicide, fertilizer mixed in a groove and maize (Zea mays L.) planted in the groove (partial tillage).Post harvest soil analysis indicated that the treatments did not appreciably affect the nutrient elements in the soil except for K which recorded a 19% increase in the last year. Tillage and fertilizer application reduced the organic matter content of the soil by 19 and 33% over the 4‐year period.The bulk density did not change much but tilled plots recorded slight increases with a range of 1.29 to 1.36 g/cm3. No‐tilled plots retained more water than tilled plots.Treatments with fertilizer gave much greater average yields than those without fertilizer. The decline in yield was related to the level of soil organic matter, method of fertilizer application, and tillage operations. Banded fertilizer had an edge over other methods. Tillage operations constituted an important factor of yield reduction, although the effect was masked by fertilizer treatment. The herbicide effect was probably on the organic matter level but this was masked by fertilizer treatments as well.In developing a more permanent form of agriculture in the tropics, soil management practices especially under a zero‐tillage system, should recognize weed control methods, and fertilizers that minimize reduction in soil organic matter and maintain high yield under continuous land use.
Development of a Wheat Yield Prediction Model1
Authors: Feyerherm A. M. , Paulsen G. M. 
Published: July 2010

AbstractThis research was motivated by a need to predict crop yields on a large‐area basis without benefit of direct measurement of plant characteristics. Mathematical models were developed that require only a modest amount of historical data for application on a real‐time basis to geographical regions other than the one where the models were developed. The models, one for winter wheat (Triticum aestivum L.) and one for spring wheat (Triticum aestivum L. and Triticum durum Desf.), predict wheat grain yields from observation of meterological and agronomic variables.Use of standardized yields, simulated water budgets, and measurement of weather events over simulated phenological stages helped to create a broad data base for model development. Weather scenarios for low and high yields can be deduced from the models as can the contribution of applied N, improved cultivars, and increased irrigation to long‐term yield increases. The models include soil factors to help explain regional differences in yield. The models also allow for reduced yield estimates due to episodic events (diseases, freezes, etc.).Root‐mean‐square errors of differences between the model and USDA estimates of yield for the U.S. Great Plains for 1955 through 1976 were 1.2 and 1.3 quintals/ha for winter and spring wheat, respectively
Wheat and Barley Growth and N Fertilizer Utilization Under Sprinkler Irrigation1
Authors: Christensen N. W. , Killorn R. J. 
Published: July 2010

AbstractInformation on the effectiveness of N fertilizer applied through sprinkler irrigation systems for springsown wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) is limited. Objectives were to determine grain yield and quality responses and N‐use efficiency when N fertilizer was applied at irrigation to wheat and barley grown on a fine‐silty, mixed Typic Haploboroll. Nitrogen fertilizer was applied to sprinkler irrigated ‘Newana’ hard red spring wheat and ‘Shabet’ malting barley at seeding or split between seeding and heading, flowering, or watery kernel growth stages. Treatments included N rates of 0, 50, 100, and 150 kg N/ha at seediig, 75 kg N/ha at seeding plus 25 kg N/ha at heading or flowering, and 50 kg N/ha at seeding plus 50 kg N/ha at heading or 25 kg N/ha at heading and 25 kg N/ha at flowering. Additionally, 25, 50, and 25 kg N/ha were applied to barley at seeding, heading, and flowering, respectively; and 100 and 25 kg N/ha were applied to wheat at seeding and watery kernel stage, respectively. Nitrogen at seeding was broadcast as NH4No3‐, Subsequent N applications were broadcast as NH4NO3, several, hours prior to an irrigation to simulate application through the sprinkler system. Wheat plots contained subplots fertilized with 15NH415NO3 containing 1.31 atom percent 15N to determine the fate and utilization efficiency of applied N. Grain yield increased from 1,100 to 4,850 and from 1,240 to 4,570 kg/ha for wheat and barley, respectively, as N rates were increased from 0 to 150 kg N/ha at seeding. When 100 kg N/ha was split between seeding and at irrigation, wheat yields decreased from 3,890 to 3,540 and 2,975 kg/ha as the amount of N applied at seeding was decreased from 100 to 75 and 50 kg N/ha, respectively. Barley yields averaged 4,130 kg/ha for treatments totaling 100 kg N/ha and were generally not affected by shifting N applications from seeding to at irrigation. Differential response to split applications of N was related to differences in number of spikes per unit area at harvest. The number of spikes/m2 decreased for wheat and increased for barley as the proportion of the N fertilizer applied at seeding decreased. Nitrogen fertilizer recovery in the straw and grain of wheat plants at harvest was 52.5 and 50.8% where 100 kg N/ha was applied at seeding or split between seediig and at irrigation, respectively. Percentage recovery of N fertilizer was lower in straw and higher in grain when N was applied at imgation as compared to seeding time application. Failure to obtain positive grain yield responses or increases in overall N fertilizer efficiency indicate no advantage to splitting N fertilizer applications between seeding and Irrigation for spring seeded wheat and barley on deep, medium‐fine textured soils
Yield of Alfalfa and Cotton as Influenced by Irrigation1
Authors: Sammis Theodore W. 
Published: July 2010

AbstractWater resource planners need water‐producton functions, the relationship between yield and evapotranspiration,to determine the economic impact of various water allocation decisions. They also need to know the transferability of the functions within and between states.Cotton (Gossypiurn hirsutum L.) and alfalfa (Medicago sativa L.) were irrigated at Las Cruces, New Mexico, with a range of water levels using a sprinkler‐line source to determine yield and evapotranspiration under deficit irrigation. Also, alfalfa was grown at five locations and cotton was grown at two locations in New Mexico, including Las Cruces, in nonweighing lysimeters that were flood irrigated to measure the yield and evapotranspiration under nonlimiting soil‐moisture conditions.A linear water‐production function was observed for alfalfa. This function appeared to be transferable to any location in New Mexico, based on data from five locations within the state, and was statistically the same as alfalfa water‐production functions for Nevada, Nebraska, and North Dakota.A linear water‐production function was also observed for cotton, but this function was applicable only for the two areas in southern New Mexico where the study was conducted. The cotton water‐production function for New Mexico was statistically different from the reported water‐production function of the similar study conducted in California. The cotton water‐production function had a lower coefficient of determination than the alfalfa water‐production function since cotton was harvested for lint and seed rather than biomass. This study indicated that biomass production may require the same amount of evapotranspiration regardless of site and management differences, as in the case of alfalfa, but that lint or seed production per unit of water will vary from place to place.
Wind‐tunnel Simulation and Assessment of Ammonia Volatilization from Ponded Water1
Authors: Bouwmeester Reinier J. B. , Vlek Paul L. G. 
Published: July 2010

AbstractSeveral techniques for the prediction of ammonia volatilization rates from rice paddies are evaluated using experimental data obtained in a wind‐water tunnel, set up to simulate rice paddy conditions.The wind tunnel results suggest that nonuniform surface conditions of waters with short fetch do not significantly limit the use of aerodynamic techniques for the prediction of ammonia volatilization rates. Comparison of volatilization rates predicted with a one‐dimensional aerodynamic technique as well as a two‐dimensional modification of this technique against those predicted from the longitudinal ammonia flux at the downwind section of a wind‐water tunnel yield differences on the order of 10%.Ammonia volatilization rates and aqueous chemistry measured under small enclosures are compared with those measured in the wind‐water tunnel. The results indicate that quantitative assessment of ammonia volatilization losses in the field is possible if air exchange rates in the enclosure are selected which yield a gas phase resistance representative of average wind conditions.
Nitrogen Sources for Bean Seed Production1
Authors: Westermann D. T. , Kleinkopf G. E. , Porter L. K. , Leggett G. E. 
Published: July 2010

AbstractBeans (Phaseolus vulgaris L.) often respond to N fertilization; however, N fertilization is not practiced for maximum seed production in southern Idaho. This suggests that the symbiotic relationship and/or soil N sources can provide most of the N needed by this legume. Our objective was to evaluate the relative contribution of the symbiotic‐nonsymbiotic N sources by studying the effects of N fertilization on the symbiotic N2 fixation and seed yields under field conditions. Experiments were conducted on silt loam soils belonging to the Portneuf series (Xerollic Calciortnids). An acetylene reduction (AR) method was used to determine the effect of N fertilization treatments on the relative seasonal N2 (AR) fixation. The symbiotic N2 fixation was also estimated by the equation, N2 = Nup − (Ni + Nm − Nh)−αNt, where Nup is the accumulated N uptake measured near physiological maturity, N1 and Nh are the amounts of soil NO3‐N in the root zone before planting and near physiological maturity, Nm is the N mineralized from soil organic N sources, and a is the recovery of the N fertilizer (Nf) applied. Estimates of the N fertilizer recoveries were obtained from two experiments using 15N‐depleted (NH4)2 SO4.The symbiotic N2 relationship contributed up to 90 kg N/ha, which was 40 to 50% of the total N found in bean plants near physiological maturity. The amount of symbiotic N2 fixed decreased as the available soil N or fertilizer N increased, and increased as the N required by the individual cultivars increased. The response to N fertilization depended upon the cultivar, as well as on the N available from soil sources. Measured fertilizer N recoveries ranged from 7 to 33%. An average of 52% of the total N uptake near physiological maturity was taken up after the maximum symbiotic N2(AR) rate occurred; while the seed contained an average of 60% of the total N uptake. A low N fertilization rate (< 50 kg N/ha) when the soil N1 was low (<50 kg N/ha) ensured an early vigorous plant growth but did not always increase seed yields. Higher N fertilization rates may be required on soils with lower amounts of mineralizable N.