bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time Distributions for Describing Appearance of Specific Culms of Winter Wheat1
Authors: Rickman R. W. , Klepper B. L. , Peterson Curt M. 
Published: July 2010

AbstractCereal plants emerge and develop tillers in response to the field environment in which they are planted and grown. If the pattern of development of productive culms can be recognized and measured, impacts of different field conditions upon plants can be assessed. This study presents a method for describing emergence and tiller appearance patterns and illustrates the use of these patterns in comparing crop development responses to field environments. Desirable environments will produce uniform populations of culms with regularly spaced appearance patterns while stressful environments cause a variety of irregular patterns.Characteristics of the populations of appearing culms can be described fundamentally by the logistic distribution function or can be approximated by the normal distribution function. The cumulative form of both functions is a sigmoid curve. The mean of the normal coincides with the 50% appearance time of the logistic. When the dispersion coefficient (s) of the normal function and the rate coefficient (k) of the logistic equation are related by ks = 1.69, the two curves differ by less than 1% of the final population size at any point. Culm appearance populations from good seedbeds appear as normal or logistic curves (considered to be the same curve) when appearances are timed by degree‐days (3°C base). Fifty percent emergence for Stephens winter wheat (Triticum aestivum L.) occurs near 100 degree‐days from planting, and tillers Tl, T2, and T3 occur at about 250, 300, and 375 degree‐days, respectively, in a fertile seedbed with adequate water. Culm appearance data that are not normally distributed may be converted to normal form with transforms or population splitting procedures. The nature of the transformation required to normalize the data may help characterize the field condition causing non‐normal appearance.
Effect of Wind on the Crop Water Stress Index Derived by Infrared Thermometry1
Authors: O'Toole J. C. , Hatfield J. L. 
Published: July 2010

AbstractA new plant or crop water stress index (CWSI) that depends on interpreting crop or foliage‐to‐air temperature differential (Tf‐Ta) shows promise in both research and irrigation water management. The method relies on the unique relation between Tf‐Ta, and atmospheric water vapor pressure deficit (VPD). However, the method of estimating the upper limit of Tf‐Ta, a critical step in CWSI calculation, was questionable and lacked field validation. We measured the upper limit of Tf‐Ta, and attendant micrometeorological variables on severely water stressed sorghum (Sorghum bicolor L.), corn (Zea mays L.), and bean (Phaseolus vulgaris L.) grown on a Typic Xerotherent, and cotton (Gossypium hirsutum L.) grown on a Typic Torriorthent. Actual measured values of the upper limit of Tf‐Ta ranged from 2.5 to 8.5 °C across crops. The poor agreement between actual and calculated values was analyzed with respect to net radiation, VPD, and windspeed. Windspeed was found to be the primary factor causing erroneous estimation of the upper limit of Tf‐ Ta, and hence CWSI values. Crop water stress index values measured at low windspeed overestimated the level of water stress while those measured at high windspeed underestimated it. Crop specific changes in the boundary layer resistance‐windspeed relationship partially explain the discrepancy between measured and calculated Tf‐Ta, upper limit values. Modification of the CWSI to account for the influence of windspeed is discussed.
Effect of Nitrapyrin on Nitrogen Transformations in Soil Treated with Liquid Swine Manure1
Authors: McCormick R. A. , Nelson D. W. , Sutton A. L. , Huber D. M. 
Published: July 2010

AbstractApplications of animal manure to soil result in nitrification of applied NH+4 — N and eventual loss of applied N through leaching and/or denitrification processes. In theory, one way to reduce the leaching and/or denitrification losses is through the use of a nitrification inhibitor. Therefore, a field experiment was conducted during the summer of 1979 to determine the effects of nitrapyrin [2‐chloro‐6(trichloromethyl)pyridine] on N transformations occurring within a band of soil‐applied liquid swine manure (LSM). Liquid swine manure (60 t ha −1) containing 0 or 50 mg nitrapyrin active ingredient/liter was injected into Chalmers silty clay loam (fine‐silty, mixed, mesic Typic Haplaquoll). The LSM application provided about 156 kg ha −1 of plant‐available N and nitrapyrin addition rates were 0 and 3 kg ha.−1 Periodically during the 24‐week experiment soil samples were obtained from the LSM application band and analyzed for NH+4 — and NO−3 — N. From 40 to 50% of added organic N was mineralized in the LSM application bands. Ammonium present in bands of LSM not treated with nitrapyrin was oxidized to nitrate within 7 weeks after application. Addition of nitrapyrin to the LSM delayed nitrification for up to 15 weeks after application. Essentially all of the inorganic N had been lost from the LSM that did not receive nitrapyrin by the 11th week after application, probably as a result of sequential nitrification and denitrification. However, in the nitrapyrin‐treated LSM high amounts of inorganic N remained during the entire experiment and greater than 50% of the inorganic N initially present was recovered after 24 weeks. These findings suggest that nitrapyrin was effective in inhibiting nitrification in manure‐treated soil and addition of the inhibitor reduced N losses following manure application.
A Low Cost Microcomputer Data Acquisition System for the Technicon Autoanalyzer1,2
Authors: Winkleman G. E. , Leyshon A. J. 
Published: July 2010

AbstractA Sinclair ZX81 microcomputer was interfaced with the telemetry output of a Technicon Auto Analyzer II colorimeter using an inexpensive analog interface, A computer program was written in BASIC to monitor the flow of samples within the Auto Analyzer system, measure peak heights, and calculate concentrations. Missing peaks are detected. The system provided totally automatic low‐cost (under $500) data acquisition and handling. Data acquisition and computations by the microcomputer were consistently as reliable as those performed by laboratory personnel. The potential for greater accuracy was believed to exist.
Photoperiod‐Sensitive Tropical Corn as a Potential Source of Biomass or Paper1
Authors: Hammes J. L. , Pendleton J. W. 
Published: July 2010

AbstractA $1 billion paper and paperboard trade deficit occurs annually in the United States. Research efforts are spent in improving woody species and in identifying new perennial and annual species for such purposes. Five photoperiod‐sensitive, exotic tropical corn (Zea maysL.) cultivars were compared with a local corn hybrid, forage sorghum (Sorghum bicolorL. Moench), and kenaf (Hibiscus cannabinusL.) for their potential biomass production at Madison, Wisconsin on a Ringwood silt loam (Typic Arguidoll) soil. One of the tropical cultivars, ‘Cortazar,’ produced the highest dry matter yield (15.52 t ha−1) and the tallest plants (370 cm). Cortazar's vegetative yield was twice that of the local hybrid and kenaf, but not higher than forage sorghum. A cultural trial conducted with the photoperiod‐sensitive cultivar ‘Tuxpeno Criollo’ indicated that early planting and a moderate plant population would increase biomass yields. Results of this study show that corn has a potential for production as a paper pulp source.
Evaluation of a Soil Inoculant for Improving Corn and Potato Yield and Quality1
Authors: Wolkowski R. P. , Kelling K. A. 
Published: July 2010

AbstractCorn (Zea maysL.) and potato (Solanum tuberosumL., ‘Russet Burbank’) were grown with and without the addition of the soil additive Symbex at different levels of fertilization. Symbex is marketed as a microbial soil inoculant claiming to accelerate decomposition of crop residue and N fixation. The efficacy of Symbex on the yield and quality of the two crops was evaluated at two sites for corn and one site for potato on a Typic Argiudoll, a Typic Hapludalf, and Typic Udipsamment, respectively, each for 3 years. Rates of fertilizer were 0, 20, 104, and 188 kg ha−1total N applied in the corn studies and 30, 50, and 100% of 756 kg ha−15‐10‐30 starter plus 224 kg ha−1of supplemental N in the potato study. Although both corn and potato yields were increased by fertilization, the use of Symbex did not affect the yield of either crop at any fertilizer rate. Foliar nutrient content of N, P, and K when compared by a paired t test over all fertility levels showed no differences associated with Symbex treatment by either crop. Symbex increased the rate of emergence of potato at all levels of fertility. A trend toward decreased size of grade US1A tubers was observed where Symbex was used.
Herbage Yield and Quality of Filegrass as Influenced by N, P, and K Fertilizer Applications1
Authors: Omaliko C. P. E. 
Published: July 2010

AbstractThe nutrient requirements of filegrass (Anthephora ampulacea, Stapf and Hubb), a potential pasture species, is hardly known. A greenhouse experiment was conducted to study the effects of applied N, P, and K fertilizers on its herbage yield and quality. Four rates of N (0, 100, 200 and 300 kg N/ha−1as ammonium sulfate); three rates of P (0, 33, and 66 kg P ha−1as single superphosphate); and three rates of K (0, 62, and 124 kg K ha−1as muriate of potash) were applied in solution in all possible treatment combinations (36 treatments). Plants were first harvested when 50% of the primary tillers were at early anthesis, A second harvest was made after 4 weeks of regrowth. Fertilizer application at 100 kg N/ha−1rate at least doubled filegrass yield (7.4 vs. 14.8 g pot−1for 0 vs. 100 kg N ha−1rates). Higher rates of N application gave further significant yield increases (19.4 and 19.9 g pot−1for 200 and 300 kg N ha−1, respectively). For the regrowth harvest, yields differed significantly such that 0 < 100 < 200 < 300 kg N ha−1. Filegrass response to applied N is represented by the following regression equations Y = 9.2 + 0.05 × (for first harvest) and Y = 1.39 + 0.018 × (for second harvest). Applied P and K fertilizers did not significantly affect the dry matter yields and concentration of other nutrients in both the leaf and stem fractions. Applied N at 100 kg ha−1rate increased N concentration of the leaf fraction but decreased P, Ca, and Mg of the leaf. Higher N rates, however, increased these nutrients in the leaf blade. Nitrogen application, at all rates, increased the stem concentrations of N from 0.49 to 1.20; P from 0.16 to 0.26; K from 0.87 to 1.12; Ca from 0.11 to 0.56 and Mg from 0.06 to 0.19% on dry matter basis. The dry matter digestibility (DMD) values for both leaf and stem fractions were relatively close (62.8 and 53.4%, respectively). The DMD of each fraction was increased by N application from 45.6 to 65.7 in the leaf and stem when the rate was increased from 0 to 300 kg N ha−1. These results were discussed in terms of herbage production and livestock requirements.
Drying Rates of Spring Triticale Compared to Wheat1
Authors: Clarke John M. , Townley‐Smith T. Fred 
Published: July 2010

AbstractSome workers have observed that triticale (X‐TriticosecaleWittmack) is slower to dry down after maturity than is wheat (Triticum spp.). Laboratory water uptake rate studies were undertaken with threshed seed of triticale lines in an effort to identify lines with potentially differing drying rates. Drying rates of four lines and one cultivar of triticale were compared with those of two hexaploid wheat (T. aestivumL.) and one tetraploid wheat (T. turgidumvar. durumL.) in windrowed and standing treatments in the field. The experiment was conducted in Saskatchewan, Canada on an Orthic Brown Chernozem; Aridic Boroll soil. Over 2 years, the triticales dried as quickly as, or in some cases, more quickly than the wheats. Similar results were obtained when the rates of kernel water loss after physiological maturity for standing wheat and triticale were compared over 4 years. The triticales tended to reach physiological maturity at higher kernel water concentrations than Glenlea wheat, which may have contributed to the faster drying rates of the triticales.
Crossing Success in Cotton in Arizona as Affected by Irrigation, Number of Flowers Pollinated, and Time of Emasculation1
Authors: Wilson F. D. , Stapp B. R. 
Published: July 2010

AbstractRetention of crossed bolls is low in plants of cotton (Gossypium hirsutumL.) that are exposed to the high temperatures and water deficits encountered commonly in irrigated desert regions. One purpose of this study was to determine the relationship of the retention of crossed bolls with number of days after irrigation and with the number of pistillate flowers pollinated with one staminate flower. Another purpose was to determine the feasibility of emasculating cotton flowers in the morning of the day of pollination rather than at the traditional time of the afternoon before pollination. For three seasons, flower buds of ‘Deltapine 61’ were hand‐emasculated from 0200 to 0600 h for 10 to 12 days through an irrigation cycle at Phoenix, Ariz. Soil type was Avondale clay loam (a fine, loamy, mixed, hyperthermic Torrifluventic Haplostolls). Groups of pistillate flowers‐10, 15, 20, 25, and 30‐were each pollinated with a single staminate flower from a breeding stock homozygous for R1, red plant color. After each daily session of crossing, 100 open–pollinated flowers were tagged to serve as controls. From this study, we observed 1) a progressive decrease over days in boll set, followed by an increase just before the next irrigation, which illustrates the transitory influence of water stress; 2) that crosses made the 1st week after an irrigation yielded almost as much total hybrid seed as those made for the entire 14‐day period between irrigations; 3) that seed yield loss would not have been severe even if limited amounts of pollen had forced us to pollinate 30 pistillate flowers per staminate flower; and 4) that emasculating flowers even as early as 0200 h on the day of pollination led to some self‐contamination.
Effect of Solar Azimuth and Infrared Thermometer View Direction on Measured Soybean Canopy Temperature1
Authors: Nielsen D. C. , Clawson K. L. , Blad B. L. 
Published: July 2010

AbstractMeasurements of radiative canopy temperature taken with infrared thermometers (IRTs) are strongly influenced by amount of crop cover and amount of viewed soil background. This influence can be minimized by making off‐nadir measurements so that mostly vegetative surface is viewed. But off‐nadir measurements vary with the relative azimuthal positions of the sun and the IRT due to the measurement of true variations in the individually sunlit and shaded canopy elements. The geometrical relationship between solar azimuth and IRT view azimuth on measured canopy temperatures was investigated for soybeans grown at two Nebraska locations in 1982. Soils at the two locations were a Typic Argiudoll and a Typic Ustipsamment. Canopy temperature as measured by the IRT declined linearly as the difference between the solar azimuth and IRT view azimuth increased from 0° to about 110°. As this difference increased to angles greater than 110°, the viewed canopy temperature remained fairly constant at about 0.30°C below the average of the canopy temperatures measured at the four cardinal directions. The declining linear relationship seen for angles between 0° and 110° was found to be more strongly defined during the vegetative growth stages than during the reproductive growth stages. This was attributed to declining heliotropic response of soybean [Glycine max (L.) Merr.] leaves as the canopy ages.
Effects of N Fertilization on Yield, Growth, and Extraction of Water by Wheat Following Soybeans and Grain Sorghum1
Authors: Sanford J. O. , Hairston J. E. 
Published: July 2010

AbstractNitrogen fertilization is an important part of wheat (Triticum aestivum L.) production. It is especially important in double‐crop wheat production because the N system is influenced by previous crop residue. Our objective was to evaluate topdressed rates of 0, 34, 68, 102, and 136 kg N ha−1 as ammonium nitrate spring‐applied to soft red winter wheat (‘Arthur’) grown in double‐cropping sequence following soybeans [Glycine max (L.) Merr] or grain sorghum [Sorghum bicolor (L.) Moench]. The soil was Okolona silty clay (a fine montmorillonitic, thermic Typic Chromudert). We also evaluated a 34 kg ha−1 rate of fall‐applied N with topdressed rates in the spring bringing total N to the same levels as the single spring‐applied topdressed rates above. The effects of previous crop on grain yield, straw yield, plant height, and N uptake were pronounced. All of these were significantly higher following soybeans. We attributed this to greater availability of N following soybeans, but have not ruled out the possibility of a phytotoxic effect associated with grain sorghum residues. There was yellowing and stunting of early wheat growth following grain sorghum across all N rates, regardless of whether fall N was applied or not. This early depression may have led to yield differences that were not completely overcome by the conditions of this study. Depletion of soil water was related to N uptake and yield. Soil moisture from anthesis throughout grain filling decreased progressively faster under wheat that received high rates of N.
Steer Performance from Two Perennial PennisetumSpecies, Switchgrass, and a Fescue—‘Coastal’ Bermudagrass System1
Authors: Burns J. C. , Mochrie R. D. , Timothy D. H. 
Published: July 2010

AbstractSubtropical perennial grasses make important contributions to productive, season‐long grazing systems in the USA. The perennial bermudagrasses, particularly ‘Coastal’ bermudagrass [Cynodon dactylon(L.) Pers.], are extremely productive, but high fiber allows only poor to moderate animal performance. Steer average daily gains (ADG) and productivity estimates of the subtropical perennials flaccidgrass (Pennisetum flaccidumGriseb.), P. orientaleRich., and switchgrass (Panicum virgatumL.) were obtained. Sequential grazing of tall fescue (Festuca arundinaceaSchreb.) and Coastal as a system (F + C) served as the standard for comparison. The grazing experiment with yearling steers was conducted on a Typic Hapludult soil for 3 years. Calendar days grazed, ADG (kg) and steers ha−1, respectively, from initiation of grazing until Coastal was stocked (period 1) averaged 53, 0.93, and 15.1 for tall fescue; 20, 1.35 and 11.1 for flaccidgrass and 40,1.07, and 8.9 for switchgrass. Number of steers ha−1was greatest on tall fescue and ADG lowest (P ≤ 0.06). Flaccidgrass supported significantly more animals than switchgrass. Summer (period 2) results (avg. 98 days) for AM; and steers ha−1, respectively, were 0.43 and 25.1 for Coastal; 0.78 and 9.1 for flaccidgrass (P. orientalewas similar), and 0.92 and 7.9 for switchgrass. Steer ADG was lowest and steers ha−1highest on Coastal, while the other grasses were similar for both. Tall fescue made little contribution because rainfall was below normal all 3 years. Seasonal results from the F + C showed most calendar days (160), lowest ADG (0.59) but similar numbers of steers ha−1(9.5) compared with respective values of 130,0.90, and 9.6 for flaccidgrass and 140, 0.96 and 8.2 for switchgrass. Flaccidgrass averaged significantly more steers ha−1than switchgrass. Gain ha−1from tall fescue in period 1 (792 kg) and Coastal in period 2 (1160 kg) was greater than the average for the other grasses, 349 and 559 kg, respectively. However, seasonal computations based on combined land areas for the F + C system yielded 1010 kg of gain ha−1. That gain did not differ from the 930 kg ha−1for the other grasses, even though the F + C system averaged 25 more calendar days. Flaccidgrass and switchgrass have quality attributes and a sufficiently long growing season to make an important contribution to an animal enterprise that values large daily animal responses. Coastal is more appropriately used in enterprises for an animal class, or portion of the season, where only moderate to low response animal−1is required.
Multiple Cropping Soybean with Oats and Barley1
Authors: Kaplan S. L. , Brinkman M. A. 
Published: July 2010

AbstractMultiple cropping and relay intercropping of soybean [Glycine max(L.) Merr.] with small grains was studied as an alternative cropping system or areas that are traditionally oriented towards production of feed for dairy cattle (Bosspp.). The objective was to evaluate multiple cropping of small grains harvested as forage and soybean harvested as seed in a dairy forage area of the north central United States. One oat (Avena sativaL.) cultivar, two barleys (Hordeum vulgareL.), and the soybean cv. Hodgson were grown in relay intercropping, double cropping, and sole cropping systems on a Plano silt loam soil (fine‐silty, mixed, mesic Typic Argiudoll) at Arlington, WI in 1977 and 1978. Relay intercropping systems were established by planting soybean into unthinned stands of small grains or by removing rows of small grains shortly after emergence and later planting soybean in the gaps. Double‐cropped soybean was planted after barley and oats were harvested as forage. Early soybean checks (sole cropping) were planted on the same date that relay intercropped soybean was planted, and late soybean checks were planted on the same date that: double‐cropped soybean was planted. Soybean row widths in all systems were 0.41‐, 0.75‐, and 0.90‐m. Early soybean checks were more productive than soybean relay intercropped in both thinned and unthinned stands of oats and barley, but late soybean checks were not always more productive than double‐cropped soybean. Yields of soybean relay intercropped in 0.45‐m rows were higher in thinned stands of barley and oats than in unthinned stands. Differences were not as large in wider rows. Cultivar differences in forage yield were not associated with consistent differences in yields of relay intercropped and double‐cropped soybean. The most productive cropping sequence was a double‐cropping system that had a forage yield of 4.93 Mg ha‒1and a soybean yield of 2.21 Mg ha‒1.