bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Nitrogen and Phosphorus Placements and Rates on Turfgrass Establishment1
Authors: King J. W. , Skogley C. R. 
Published: July 2010

AbstractThe effects of several rates, ratios, and placements of nitrogen and phosphorus on bluegrass‐red fescue turfgrass establishment were investigated.Fall and spring field trials were conducted on Bridgehampton silt loam of low fertility. The fertilizer placement treatments were (1) surface applied, (2) mixed into the‐upper 10 cm of soil, and (3) 3/4 mixed into the upper 10 cm of soil and 1/4 surface applied. Phosphorus in the form of superphosphate was applied at rates of 490, 980, 1,960 and 3,920 g of phosphorus/100 m2. Nitrogen in the form of ammonium nitrate was applied at rates of 375 and 1,470 g of nltrogen/100 m2.The effects of establishment treatments lasted for only a few months. Initially, the higher nitrogen rate resulted in improved turfgrass quality and top growth. No seedlling injury from the 1,470‐g nitrogen rate was observed. The surface and 3/4‐1/4 fertilizer placements produced equally satisfactory results. Response to phosphorus levels was inconsistent. No significant differences in root weights were detected. Applications of maintenance fertilizer resulted in great improvement in turfgrass quality and top growth.
Timing and Correlation of Major Developmental Events in Maize, Zea mays L.1
Authors: Siemer E. G. , Leng E. R. , Bonnett O. T. 
Published: July 2010

AbstractTiming and sequence of major developmental events were studied in Corn Belt dent inbred lines and hybrids,with two dates of planting and two growing seasons. Mean developmental characterizations and sequences were established both for quantitative and qualitative events. The number of days from planting to a given event was greatly influenced by genotype. Hybrids developed faster than corresponding inbred lines in all respects except the full achievement of kernels per row potential; hybrids produced significantly more kernel primordia per row. Developmental differences attributable to planting date or growing season appeared to leflect effects of air temperature, soil moisture, or both. Low temperature and moisture deficiency apparently retarded development. Internode elongation, axillary bud development and cessation of ear elongation proceeded acropetally, while ear initiation was basipetal. Four pairs of events were closely related in time: (1) tassel initiation and the beginning of stalk elongation, (2) top car initiation and beginning of rapid stalk elongation, (3) accelerated tassel peduncle elongation and tassel emergence, and (4) accelerated top ear elongation and attainment of maximum top ear kernels per row potential. Important physiological relationships may exist between these related events.
Increase in Yield of Wheat (Triticum aestivum L. variety ‘N.P. 718’)
Authors: Mohan H. Y. , Rustagi P. N. 
Published: July 2010

AbstractPlants of wheat were given two to four aqueous sprays of Mendok at 10‐day intervals at 250, 500, and 1,000 ppm. The first foliar application was made at the flag leaf stage. The treatments failed to elicit male or female gamete sterility. However, at low dosages the treated plants were shorter, had stiffer straw, were less susceptible to lodging, and gave a higher grain yield as compared to the controls. Augmentation in grain yield was particularly significant at 250 ppm (two and three sprays) on per plant basis, and at 1,000 ppm (two, three, and four sprays) on the basis of the tallest earing tiller. Increase in grain yield was due to greater number of earing tillers (except at 1,000 ppm, four sprays, where there was actually a decrease) and grains per ear.
Influence of Night Temperature on Growth and Development of Cotton (Gossypium hirsutum L.) IV. Seed Quality1
Authors: Gipson J. R. , Joham H. E. 
Published: July 2010

AbstractDifferent night temperatures were maintained through‐out the seed development period of two divergent varieties of cotton growing in the field during the 1963, 1964, and 1965 seasons. Viability and oil and nitrogen content of cottonseed of both varieties were found to be affected by the night temperature prevailing during the seed development period. Decreased night temperatures resulted in lower germination percentages and in reduced oil and nitrogen content of the seed. Differences were also noted between varieties and seasons, and an inverse relationship existed between oil and nitrogen content for both varieties at all temperature regimes.
Potential Evapotranspiration as Influenced by Wind1
Authors: Skidmore E. L. , Jacobs H. S. , Powers W. L. 
Published: July 2010

AbstractThe contribution of wind to calculated potential evapotranspiration was investigated with applications for the climate of the Great Plains. A revised combination model proposed by van Bavel for computing instantaneous potential evapotranspiration was used. The model contains two terms that are expressions for the portions of potential evapotranspiration primarily due to net radiation and wind, respectively. With ambient water vapor pressure 20 mb, temperature 30C, wind 2, 4, and 6 m sec−1 at 2 m with a roughness length of 1 cm, contribution of wind dominant term to evaporation from a wet surface is 0.15, 0.30, and 0.45 mm hr−1, respectively. At 10‐mb vapor pressure and the same temperature, the corresponding evaporation rates are 0.22, 0.43, and 0.65 mm hr−1. On representative and consecutive “nonwindy” and “windy” days at Manhattan, Kans. (average daily windspeeds at 45 cm were 0.88 and 2.26 m sec−l), the wind dominant term contributed 33 and 113%, respectively, as much as the radiation dominant term to the total calculated potential evapotranspiration. For these 2 days the ratio of potential evapotranspiration to net radiation was 0.98 and 1.60.
Effect of Some Seed Characteristics on Mechanically Induced Seedcoat Damage in Navy Beans (Phaseolus vulgaris L.)
Authors: Dorrell D. G. , Adams M. W. 
Published: July 2010

AbstractNavy bean seeds were evaluated for their response to mechanical abuse. Seed of all lines was hand threshed and equilibrated to a constant moisture content prior to damaging.Highly significant differences were found among lines in their reaction to seedcoat cracking. Seed weight, shape, density and seedcoat anatomy were examined as components contributing to seedcoat damage. Seedcoat cracking increased as the seed weight increased. Normal within‐line weight differences were small and self‐compensating, but between lines weight variation had a highly significant effect on cracking. Cracking also increased as the shape became more nonspherical. Increased seed density improved seedcoat tolerance to mechanical abuse but caused a nonsignificant increase in cotyledon splitting. Tolerant bean lines generally had a thinner parenchymatous layer underlying the osteosclerids. There was no difference in the thickness of the osteosclerid and macrosclerid layers between tolerant and susceptible lines.
Yield‐Protein Relationships in Wheat Grain, as Affected by Nitrogen and Water1
Authors: Terman G. L. , Ramig R. E. , Dreier A. F. , Olson R. A. 
Published: July 2010

AbstractHighly significant inverse yield‐protein relationships in wheat grain were found at each level of applied N in an irrigation‐N rate experiment on hard red winter wheat over a 3‐year period at North Platte, Nebraska. The chief effect of applied N with adequate water was to increase yields, while the chief or entire effect with severe water deficits was to increase protein content. In intermediate situations, N increased both yield and protein content.In dryland experiments in 1966 and 1967 showing significant grain yield response to applied N, protein content also increased. Where little or no yield response occurred, N mainly increased protein content. Content of NO3−N in the soil to a depth of 180 cm was also important in yield‐protein relationships.Average protein contents of about 20 hard red winter wheat varieties at different locations in Nebraska in 1966 and 1967 were also negatively related to grain yields. Protein contents varied more widely among locations than among varieties at each location.
Influence of Cutting Height in Darkness on Measurement of Energy Reserves of Tall Fescue1
Authors: Matches Arthur G. 
Published: July 2010

AbstractThe objective in these investigations was to determine whether measurement of the energy reserve status of tall fescue plants is influenced by height of cut in darkness.Vegetatively propagated ‘Kentucky 31’ tall fescue plants, grown in the greenhouse, were preconditioned to have either high or low energy reserves. Plants within each reserve group were then defoliated at cutting heights of 0 (soil level), 3, 6, or 9 cm and placed in a dark chamber. Levels of energy reserves were estimated as the amount of regrowth in darkness expressed on a per plant or a per tiller basis.Generally, etiolated growth per plant or per tiller increased as the cutting height increased. This indicates that an energy reserve sink exists in the stem bases of tall fescue. High‐reserve plants were the most responsive to differences in height of cut. Concentration of reserves were not necessarily uniform throughout the stem base. We believe height of cut for energy reserve determination should not be less than 3 cm, and the 6‐ and 9‐cm heights appear satisfactory for most investigations.
Drying or Anaerobically Preserving Small Lots of Grain for Seed or Food1
Authors: Dexter S. T. , Chaves A. M. , Edje O. T. 
Published: July 2010

AbstractSeeds of many species were stored with small decreases in vialibity in air‐tight containers held at low relative humidities with wooden blocks impregnated with suitable salts.Various sawdusts were repellent or toxic to granary and bean weevils.Damp grains were dried by mixing with salt—impregnated sawdust. Molding was avoided and germination and edibility were preserved if the proportions of grain and desiccant were such that water uptake did not exceed that to produce a saturated solution.Corn at moisture contents of 21–31%, stored anaerobicalliy, evolved far more carbon dioxide at the higher moisture content (alcoholic‐lactic acid fermentation) flushing out air. Viability was soon lost. When molds were avoided, fermented meals were palatable. Nigerians preferred the flavor of the slightly fermented grain to dried grain when prepared in their customary manner.Good viability was maintained in drying corn with sawdust‐salt in a 2‐cycle system.
Evapotranspiration from a Snap Bean Crop1
Authors: Black T. A. , Tanner C. B. , Gardner W. R. 
Published: July 2010

AbstractA model is described in which transpiration from a loosely structured canopy is calculated from the potential evaporation, the evaporation from the soil, and the stomatal resistance weighted by the leaf area index of the field. Estimation of the evaporation from the soil requires the net radiation at the soil surface and the surface soil water content. A test of the model on snap beans (Phaseolus vulgaris L.) resulted in a 4% overestimation attributed to the inaccuracy of the estimate of the evaporation from the soil.
Effects of Short Periods of Anaerobic and Near‐Anaerobic Conditions on Water Uptake by Tobacco Roots1
Authors: Willey C. R. 
Published: July 2010

AbstractIntact tobacco roots growing in nutrient solution spray in a sealed chamber were treated with mixtures of O2, N2, and CO2 gases. Oxygen and water uptake by roots and plant stem diameter were recorded.Anaerobic treatments produced by flushing roots with N2 or N2 plus 21% CO2 gases for 6 hours decreased water uptake 50% or more, but restoration of air to roots caused a rapid recovery of water uptake. Root injury was caused by both treatments, as evidenced by reduced oxygen uptake following each treatment. Gases with 1% or more oxygen had little or no effect on water uptake. Treatment gases containing up to 21% CO2 had the same effect on water uptake as treatment gases without CO2. Oxygen deficiency appears to be the primary cause of the initial decrease in water uptake and wilting of tobacco subjected to poor root aeration.
Weather and Technology in the Production of Soybeans in the Central United States1
Authors: Thompson Louis M. 
Published: July 2010

AbstractMultiple curvilinear regression analysis was used to measure the influence of weather on the yield of soybeans. A linear time trend was introduced to measure the influence of technology. In the five states, Illinois, Indiana, Iowa, Missouri, and Ohio, yields increased at an annual rate of 21.5 kg per ha from 1930 to 1968. Highest yields have been associated with warmer than normal temperatures in June but with cooler than normal temperatures in July and August. Highest yields have been associated with normal precipitation from September through June and with above normal rainfall in July and August.
Effect of Mulches and Bed Configuration. II. Soil Temperature and Growth and Yield Responses of Grain Sorghum and Corn1
Authors: Adams John E. 
Published: July 2010

AbstractClear plastic film and petroleum mulch were used on Austin clay and Houston Black clay to evaluate their effects on soil temperature and on the growth, development, and yield responses of corn (Zea mays L.) and grain sorghum (Sorghum bicolor (L.) Moench). Three bed configurations also were used in conjunction with the mulches with grain sorghum.Mulches had a highly significant effect on average soil temperature at 7.6 cm below the surface. Soil temperature under clear plastic film 3 weeks after planting had increased 2.6, 2.2, and 1.8C at depths of 30, 61, and 91 cm, respectively.Mulches increased the rate of growth of both corn and grain sorghum significantly (5% level) and also affected morphological development, with clear plastic having the most effect. Bed configuration had a significant effect on sorghum growth when used with mulches. Clear plastic mulch accelerated growth and morphological development sufficiently to cause 50% bloom to occur 8 to 10 days earlier for both corn and grain sorghum.Clear plastic mulch increased grain sorghum yield significantly, but mulches had no significant effect on corn yield. Bed configuration caused a significant increase in grain sorghum yield in 1964 but had no important effect on yield in 1963.
Response of ‘Atlas’ Cotton to Variations in Plants Per Hill and Within‐Row Spacings1
Authors: Hawkins B. S. , Peacock H. A. 
Published: July 2010

AbstractTo determine the effects of variations in plants per hill, spacing arrangements, and plant populations on agronomic and fiber properties of cotton (Gossypium hirsutum L.) we conducted a 2‐year study at Experiment, Ga., using ‘Atlas’ cotton on Cecil scl. Each trial was a randomized block split‐plot with number of plants (2, 3, 4, or 5 per hill) as the main plots and within‐row spacings (20, 40, and 60 cm) as subplots. The variations in plants/ hill and spacings represent a range in population of 32,110 to 240,825 plants/hectare.Significant differences in yield due to years and to within‐row spacings were found, but number of plants per hill did not affect yield. The plants in hills spaced 20 and 40 cm apart produced higher yields than the plants spaced 60 cm. A population range of 96,330 to 144,495 plants/ha produced best yields.We found differences in lint percentage and boll size due to years, plants/hill, and within‐row spacings. Lint percentage was highest and bolls were largest from plants at the 60‐cm spacing and when there were 2 plants/hill. The only significant difference in seed size was that associated with years. Fiber length differences were due to years, plants/hill, and within‐row spacings; the longest fibers were produced by 3 plants/hill and by plants at 40‐cm spacing. Differences in fiber strength were due to years and within‐row spacings; the strongest fibers were produced by plants spaced 60 cm apart. Fiber fineness was influenced by years only.The following interactions were found:

Years × plants/hill: boll size, fiber length, fiber fineness, yield, lint percentage, and seed size.

Years × spacings: lint percentage, boll size, and fiber fineness.

Plants/hill × spacings: lint percentage.

There were no significant second order interactions.Although mean differences were statistically significant, they are so small that they may be of no practical value. However, results demonstrate the relative stability of the characters stodied over a wide range of planting patterns and population densities.
Relation of Weather to the Influence of Hay Crops on Subsequent Corn Yields on a Chalmers Silt Loam1
Authors: Barber Stanley A. 
Published: July 2010

AbstractThe effect of hay crops [alfalfa (Medicago sativa L.), bromegrass (Bromus inermus L.), and a mixture of the two] on soil productivity as measured by corn (Zea mays L.) yields was investigated in field experiments conducted from 1952 to 1969. Corn following hay yielded more than corn following corn. The greater the number of years of corn subsequent to hay, the lower the corn yield. There was a negative linear correlation between corn yield and log of year of corn subsequent to hay. The slope of this relation varied with year and was correlated with 8‐week precipitation and 4‐week degree days following corn planting. The slope was greater as precipitation decreased below 15 cm or increased above 20 cm and also as degree days increased.
Soil and Nutrient Losses in Runoff with Selected Cropping Treatments on Tropical Soils1
Authors: Barnett A. P. , Carreker J. R. , Abruna Fernando , Jackson W. A. , Dooley A. E. , Holladay J. H. 
Published: July 2010

AbstractThe soil and nutrient losses in runoff for selected cropping systems were studied using artificial rainfall techniques on three soils in Puerto Rico in 1967. This study was undertaken to determine the erosion control effectiveness of and nutrient removal in runoff from selected cropping systems. Soils were Humatas clay, Juncos silty clay, and Pandura sandy loam. Artificial rain was applied at 6.4 cm/hr fox 60 rain (Storm 1), followed 10 min later by 12.7 cm/hr for 60 min (Storm 2). Storms and 2 were combined and designated storm 3, representing less than 2‐ to more than 500‐year frequency storms. Cropping systems tested were fallow, conventional tobacco (Nicotiana sp.), mulch‐tilled tobacco, tobacco in grass strips, pangolagrass (Digitaria decumbens), and pangolagrass with all aboveground parts removed. Slopes ranged from 26 to 46%; plots were 10.7 m long. Test areas had been in grass for several years.Final infiltration rates were 3.7, 0.9, and 6.2 cm/hr for Humatas clay, Juncos silty clay, and Pandura sandy loam, respectively. All soils were highly aggregated and remained so throughout all storms. The low infiltration rates of Juncos silty clay are misleading. Actually, most of the rainfall infiltrated this soil but returned as interflow at the lower end of the plots.All soils were quite resistant to erosion due to their high degree of aggregation and in part to the grass grown in previous years. Tillage increased storage capacity in the soil and reduced runoff. All cropping treatments were effective in reducing erosion when compared with fallow, except on Humatas clay, where the fallow treatment permitted the least erosion. Average erosion on all treatments from Humatas, Juncos, and Pandura soils were: Storm 1 — 0.87, 0.51, and 0.06; storm 2 — 5.12, 1.20, and 6.63; and storm 3 — 6.00, 1.72, and 6.69 MT/ha, respectively.Nitrogen, potassium, calcium, magnesium, sulfur, and chlorine in runoff were measured from conventionally tilled tobacco during storm 1. Treated plots received by broadcasting 1,120 kg/ha (2.27 kg/plot) of 12‐6‐16 (N, P2O5, K2O) fertilizer 1 kr before tests began. Concentrations were high at the initiation of runoff and decreased with time as the volume of runoff increased. The average concentration of N ranged from 0.01 to 2.02 ppm, which is well below accepted public health standards. Potassium ranged from 0.01 to 2.29 ppm. Concentrations were highest fox all nutrients in runoff from the fertilized Juncos silty clay plots, because almost all runoff from this soil was actually interflow—infiltrated water that moved through the tilled zone and along the tilled‐untilled interface and then surfaced at the lower end of the plot. Although measured as runoff, no surface flow occurred except at the lower 0.3 to 0.6 m of the plots.
Water Uptake and Radicle Emergence of Cottonseed as Affected by Soil Moisture and Temperature1
Authors: Wanjura D. F. , Buxton D. R. 
Published: July 2010

AbstractCottonseed (Gossypium hirsutum L.) germination was studied to estimate the effect of a wide range of constant soil temperatures and moisture tensions on seed water uptake and germination. This information was utilized in developing relationships expressing germination response as a function of the two soil parameters. Seed were placed in covered plastic cups containing soil, and seed moisture changes were measured until radicle emergence occurred. Constant temperatures were maintained by water‐bath tanks. Radicle emergence time decreased according to a Q10 relationship between 15.6 and 32.2 C with little change at 37.8 C. Water uptake rate increased with higher temperatures and lower soil moisture tensions (.3 to 10 bars). Seed moisture content at 3‐mm radicle emergence tended to be higher at the extreme temperatures (15.6 and 37.8 C) than at intermediate temperatures. Under some constant temperature and moisture environments, seeds apparently absorbed water in excess of the minimum requirement for radicle emergence. A temperature decrease of 6.2 C caused the same increase in variance of radicle lengths as an increase of 1.1‐bars soil moisture.
Interrelationships of Aluminum and Manganese on the Potato Plant1
Authors: Lee C. R. 
Published: July 2010

AbstractPotatoes (Solanum tuberosum L.) var. ‘Netted Gem’ were grown in nutrient culture solutions and sand cultures to study the interrelationships of Al and Mn on plant growth, mineral nutrition, and tuber yield. Counteracting effects of Al and Mn levels in the growth medium were observed in the color of plant tops. Visual symptoms of Mn‐induced Fe deficiency in nutrient solution cultures were associated with Mn/Fe concentration ratios of 18 or more. Aluminum counteracted these symptoms by increasing plant Fe content and decreasing Mn/Fe ratios to less than 18. Absorption and translocation of P, Ca, and Mg were affected by the addition of either Al or Mn to the nutrient solution cultures. In sand cultures, Al stunted plant tops, while Mn lengthened plant tops. Potato tuber yields were reduced by Mn at a low Al level (0 ppm), not affected by Mn at intermediate Al levels (5 to 10 ppm) and increased by Mn at a higher Al level (20 ppm). The number, size, and specific gravtity of tubers produced were affected by Al levels but not by Mn levels. It is concluded that a more accurate evaluation of the influence of soil acidity on potato production can be obtained when the effects of both soluble Al and Mn in podzol soils are considered.
Nodulation and Nitrogen Fixation by Two Soybean Varieties as Affected by Phosphorus and Zinc Nutrition1
Authors: Demeterio Jefren L. , Ellis Roscoe , Paulsen Gary M. 
Published: July 2010

AbstractSymbiotic N fixation by soybeans [Glycine max (L.) Merr.] is one factor determining yields of this important crop. Microelements have been shown to be important in metabolic processes in plants. This investigation was conducted to determine the effects of Zn and P on growth, nodulation, and N fixation, in two soybean varieties grown in solution cultures. Zinc deficiency decreased shoot weights, Zn concentrations in all plant parts, nodule weights, nodule leghemoglobin concentrations, and amounts of N fixed. Growth and P and Zn concentrations in one or more plant parts and nodule weights were greater for the P‐tolerant variety than for the P‐sensitive variety. Excess P decreased growth of all plant parts, nodule weights, nodule leghemoglobin concentrations, and amounts of N fixed. Nodule weights and amounts of N fixed were greater for the P‐tolerant variety, particularly at the higher P level. Zinc deficiency and excess P may influence N fixation directly by affecting nodule nutrition and indirectly by affecting host nutrition.