bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adaptation of Cotton Genotypes to an Acid, Manganese Toxic Soil1
Authors: Foy C. D. , Webb H. W. , Jones J. E. 
Published: July 2010

AbstractCertain soils of the Eastern Cotton Belt are potentially Mn‐toxic. The problem is not always economically prevented or corrected by conventional soil management practices. An alternative or supplemental procedure is to develop plant genotypes having superior resistance to Mn toxicity.Sixty‐five cotton (Gossypium species) genotypes (cultivars, strains, and breeding lines) were screened in greenhouse pots of an acid (pH 5.1), Mn‐toxic Grenada (fine silty, mixed, thermic, typic, Fragiudalffs) silt loam. Nine of these genotypes, plus two from Brazil, were compared on the same soil at pH 5.1 versus pH 6.9. The cotton germplasm evaluated differed widely in resistance to Mn toxicity as indicated by “crinkle leaf” symptoms and vegetative top dry weight. Genotypes showing greatest resistance included C310,73‐307, LaDSIS 12513; and LaDASB 12609. Manganese sensitive genotypes included C‐Sgl,70‐517; C‐417‐2912; and Coker 201.Top dry weights of cotton genotypes on the unlimed, Mn‐toxic Grenada soil at pH 5.1 were negatively and highly significantly correlated with crinkle leaf rating. However, top dry weights were not significantly correlated with Mn concentrations in either the two youngest leaves (fourth or fifth) or in samples composed of the three youngest leaves plus petioles. Hence, different internal Mn concentrations are required to induce crinkle leaf symptoms and reduce top dry weights in the different genotypes studied. Crinkle leaf symptoms were significantly and positively correlated with Mn concentrations in the two youngest leaves but not with those in leaf plus petiole samples.Results indicate that cotton genotypes differ significantly in tolerance to excess Mn. The development and use of Mn tolerant cultivars would be helpful in situations where the control of Mn toxicity by soil management may not be economically feasible.
Seed Element Uptake, Grain Yield, and Bird Damage of Methiocarb‐Treated Sorghum Hybrids1
Authors: Duncan R. R. , Boswell F. C. 
Published: July 2010

AbstractBird damage to ripening grain sorghum [Sorghum bicolor (L.) Moench] is a multi‐million dollar problem in the U.S.A. Methiocarb [4‐(methylthio)‐3,5‐xylyl methylcarbamate] (MesurolR) is a chemical insecticide which provides broad spectrum nonlethal avian repellency. This chemical insecticide is not labelled for spray application on ripening grain. This field study, conducted on a Cecil sandy loam soil (Typic Hapludult) during the 1978 and 1979 growing season, sought to investigate uptake of elements into the seed, yield and yield components, height, and bird damage ratings of five sorghum hybrids and to compare results on methiocarbtreated and check plots.Spray treatments, applied in a randomized block split plot design, significantly reduced seed concentrations of N, K, Mn, and Cu, increased P, and did not affect Zn and Fe. The reduction in N resulted in a 5.1% reduction in crude protein. Copper concentration in the seed was reduced by more than 25% after methiocarb treatment. Grain yields were 1,080 kg/ha higher on the treated than on the check plots. Test weight was 2.2 kg/hl higher, 300‐kernel weight was 0.7g higher, plants were 8 cm taller, and bird damage was 39% lower on the treated than on the check plots. Correlation Coefficients were considerably different on the treated versus check plots, especially as related to N content, test weight, and bird damage influences on yield. Methiocarb treatment of ripening grain sorghum provided an effective chemical method for nonlethal bird repellency and more stable yields under bird pressure. However, the significant decrease in N would result in a lower crude protein content. The additional element changes due to methiocarb treatment coupled with reduced crude protein may have a major impact on feed rationing and utilization. The beneficial aspects of this chemical treatment should be weighed against the detrimental aspects when using the material during grain filling.
Variability Observed in Centipedegrass Grown from 60Co Irradiated Seed1
Authors: Dickens R. , Johnston W. J. , Haaland R. L. 
Published: July 2010

AbstractCentipedegrass [Eremochloa ophiuroides (Munro) Hack.] has shown limited variability morphology and poor cold tolerance in the 64 years since its introduction into the United States. Variation in morphology and other parameters has been increased in other species by subjecting seed or vegetative parts to ionizing radiation. The purpose of this study was to observe and measure variation in morphology, cold tolerance, and growth habit of centipedegrass grown from irradiated seed. Centipedegrass selections grown from seed exposed to gamma radiation (0 to 80 kR) from a 80Co source were observed for variability in morphology, cold tolerance, and growth habit. No seedling emergence occurred at exposures greater than 40 kR. Irradiated plants had blade widths of 3.7 to 6.8 mm (controls 4.0 to 6.1 mm), blade length of 1.8 to 6.3 cm (controls 2.5 to 4.7 cm), and internode lengths of 0.6 to 4.1 cm (controls 2.0 to 4.1 un). Approximately 7% of the irradiated plants had a dwarfed growth habit, primarily due to shortened internode length. Environmental chamber tests indicated that several irradiated selections were equal or superior in cold tolerance to nonirradiated controls, and to ‘Oklawn’, ‘Tennessee Hardy’, ‘Mississippi 2’, and FC‐2. In field studies conducted on a Dothan sandy loam (Plinthic Paleudult), more than 40% of the irradiated plants had an establishment rate from sprigs equal to that of the controls; however, none was superior and 4% were inferior. Variability was also noted in turfgrass color and seedhead production among the irradiated selections. Seven percent produced no seedheads during the 2 years following establishment. Variability observed in these studies indicates the potential use of gamma radiation of seed to improve several turfgrass quality parameters in centipedegrass.
Organic Matter and N Effects on Soil Nitrite Accumulation and Resultant Nitrite Toxicity to Tobacco Transplants1
Authors: Hamilton James L. , Lowe Richie H. 
Published: July 2010

AbstractExtended rainy periods during the first few weeks after setting tobacco (Nicotiana tabacum L.) may result in a disorder of tobacco called organic matter toxicity. The decay of organic matter in a soil with moisture levels near field capacity (where O2 diffusion is slower) may deplete the soil O2 enough that nitrite accumulates. Our purpose was to study the accumulation of nitrite in soil with organic matter and N added, and the toxicity of nitrite to tobacco.To determine the effects of nitrite, burley tobacco (‘Ky 14’) was transplanted into pots containing gravel and irrigated with half‐strength Hoagland solution plus 0, 5, 10, and 15 ppm of nitrite. Tobacco root tips were killed when ntrite concentrations exceeded 5 ppm.To determine the effects of organic matter and N fertilizer of nitrite accumulation in soil, we determine weekly for 8 weeks the nitrite concentration in pots with: a) organic matter and N fertilizer added, b) only N added, and c) neither organic matter nor N added (controls). Moisture was adjusted to 90% field capacity each day. Tobacco plants were transplanted into the pots at 2, 4, and 6 weeks after preparing the treatments. Nitrite accumulated in the soil layer containing organic matter for 2 weeks, reaching a concentration of 60 ppm. It then started to decrease but remained at toxic levels for 5 weeks. Where no organic matter was added with the N, nitrite levels were toxic only in the sample taken the first week. Tobacco plants transplanted to soil 2 weeks after organic matter was added never grew or developed a root system. The dry weight of plants transplanted 4 weeks after organic matter was added was about one‐half that of the control and plants transplanted 6 weeks after treatments were applied did not differ.
Legume and Mineral N Effects on Crop Yields in Several Crop Sequences in the Upper Mississippi Valley1
Authors: Baldock Jon O. , Higgs Roger L. , Paulson William H. , Jackobs Joseph A. , Shrader William D. 
Published: July 2010

AbstractThe total effect of legumes on subsequent crop yields may be divided into two categories: (i) the effect of the N that they supply, and (ii) the net effect of all other contributions. Knowing the size of these two effects, plus the N response of the subsequent crops, allows N fertilization to be optimized for decreased energy use and for reduced pollution potential. Because the size of the legume effects vary, a study was made to estimate them on a mesic, Typic Hapludalf soil at Lancaster, Wisconsin from 1967–1976. The crop species included alfalfa (A, Medicago sativa L.), corn (C, Zea mays L.), oats (O, Avena sativa L.), and soybeans [S, Glycine max (L.) Merr.] in five crop sequences: continuous C, CSCOA, CCCOA, CCOAA, and COAAA. Four N treatments: 0, 84, 168, and 336 kg/ha were applied only to C. Crop sequence phases were assigned to whole plots in a randomized, complete block design with the N treatments in subplots. There was a highly significant effect of years on all crops due to weather variation and crop variety changes. Soybeans and A did not respond to residual N. Alfalfa yields were the same in all rotations (7.6 ± 0.04 metric tons dry matter/ha/year). The mean 0 yield (Y, quintals/ha) response to residual N (kg/ha) was described by Y = Minimum C(18.4 + 0.0354N), 24.93. Both A and S increased yields of C following these legume crops. Most of the increase was due to their N contribution, which was estimated with a Mitscherlich‐Spillman N response model as 50, 66, 51, 25, 3, 84, 24, and 71 kg N/ha to CSCOA, CSCOA, CCCOA, CCCOA, CCCOA, CCOAA, CCOAA, and COAAA, respectively. The increases in C yields above that due to the legume N were estimated as the difference between the predicted maximum rotational and continuous C yields, specifically: 11, 8, 9, 4, 4, 11, 6, and 11 quintals/ha (in the same order as above).
Herbage Dry Matter Yields of Switchgrass, Big Bluestem, and Indiangrass with N Fertilization1
Authors: Hall K. E. , George J. R. , Riedl R. R. 
Published: July 2010

AbstractHerbage dry matter (DM) yield potential and N requirement of native perennial, warm‐season grasses must be known before these species can be effectively used in forage‐livestock systems. This study was initiated to determine the herbage yield response of ‘Blackwell’ switchgrass (Panicum virgatum L.), ‘Kaw’ big bluestem (Andropogon gerardi Vitman), and ‘Nebraska 54’ indiangrass (Sorghastrum nutans L. Nash) to N fertilization.Four replications of a randomized complete block field experiment were established on a Clarion loam (Typic Hapludoll) soil in 1971. A four‐cut management system was used in 1974; a two‐cut system was used during 1975–1976. Applications of ammonium nitrate (34‐0‐0) were made on 21 May 1974 and 13 May 1975 at 0, 75, and 150 kg N/ha levels. Levels of 0, 75, and 150 kg were applied in 1976 as urea (45‐0‐0) on 22 May and again on 3 July after the first harvest. Two of the four replications received 50 kg P/ha as triple superphosphate (0‐46‐0) and 100 kg K/ha as K2SO4 . MgSO4 (0‐0‐22) on 7 May 1976. The K source included 60 kg Mg/ha and 118 kg S/ha.Switchgrass, big bluestem, and indiangrass produced herbage dry matter (DM) yields of 6.14, 6.29, and 5.59 metric tons/ha, respectively, when averaged over N levels and years. In 1974, big bluestem out‐yielded the rest, and in 2 out of 3 years indiangrass yielded significantly less than one or both of the other species. All species generally responded positively to N through 75, and often through 150 kg N/ha.No herbage yield response was observed in 1976 to applied P and K fertilizers, the latter containing both S and Mg.Herbage DM yields generally increased with each of three successive harvests in 1974, whereas second harvest yields decreased with a two‐cut management system used in 1975 and 1976. Relatively unfavorable July–August precipitation seemed primarily responsible for lower second harvest DM yields.A 5 Oct. 1974 harvest of aftermath herbage cut at a 5‐cm height suggests that 2.2 to 2.4 metric tons/ha of herbage would be available for use by nonlactating beef cows. No species difference in DM yield was observed, suggesting equal carrying capacity/ha, for the aftermath.
Water Use by Forage Species1
Authors: Fairbourn Merle L. 
Published: July 2010

AbstractForage production on the High Plains of Western United States might be done more economically if research provided more water‐use information for species. A study was made to determine (1) water‐use efficiency and (2) ability to use available soil water during a harvest growing period. Forages common to the area were evaluated in both greenhouse and field environments. The legume species evaluated were ‘Alsike’ clover (Trifolium hybridum), ‘Dawson’, ‘Fremont’, ‘Ladak’, ‘Team’, ‘Travois’, and ‘Vernal’ alfalfa (Medicago sativa L.), ‘Lutana’ cicer milkvetch (Astragalus cicer L.), and ‘Remont’ sainfoin (Onobrychis vicaefolia Scop.). Pasture grasses evaluated were ‘Fawn’ tall fescue (Festuca arundinacea Schreb.), Garrison creeping foxtail (Alopecurus arundinaceus Poir), ‘Latar’ orchardgrass (Dactylis glomerata L.), ‘Grennar’ intermediate wheatgrass [Agropyron intermedium (Host) Beauv. L.], thickspike wheatgrass [A. dasystachyum (Hook) Scribn.] and ‘Regar’ bromegrass (Bromus biebersteinii Roem & Schult.); while range grasses were blue grama [Bouteloua gracilis (H.B.K.) Lag], crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.], slender wheatgrass [A. trachycaulum (Link) Malte], western wheatgrass (A. smithii Rydb.), and green needlegrass (Stipa viridula Trin.). The study was made on Altvan soil, a fine, sandy, clay loam belonging to the mixed mesic family of aridic arguistolls. Water use was monitored by gravimetric method and by tensiometers in the first and second studies, respectively. Transpiration in the greenhouse during a crop growing period ranged from 7.2 cm for the milkvetch to 15.5 cm for Regar bromegrass. Blue grama had the highest water‐use efficiency of all species but was able to utilize only a relatively small amount of the available water in forage production. Growing the plants in a field environment increased evapotranspiration by 100 to 200% compared with that in the greenhouse. Thickspike wheatgrass appeared to be capable of adapting to either a semiarid or humid climate but range grasses studied were unable to use large amounts of available water.
The Mitscherlich Plant Growth Model for Determining Critical Nutrient Deficiency Levels1
Authors: Ware G. O. , Ohki K. , Moon L. C. 
Published: July 2010

AbstractThe success of a plant tissue analysis program depends on the calibration relating growth and nutrient concentration in specified plant tissues for each essential element. The minimal nutrient concentrations in tissues associated with maximum growth have been determined from calibration curves that were drawn free‐hand to best fit the respective X and Y values in graphical plotting. Statistical models to establish critical deficiency levels related to 90% maximum growth are desirable to reduce the arbitrariness of the graphical procedure.A modified Mitscherlich response equation was used to quantify critical deficiency levels by characterizing plant growth as a function of tissue nutrient concentration. The model presented is y = β(1 — γe‐ax) where y is the plant yield at tissue concentration x, and α, β, and γ are parameters to be estimated. Critical deficiency levels determined from the Mitscherlich model were significantly greater (P < 0.05) than the previously reported nutrient values of the same studies utilizing the graphical procedure.
Physiological Responses to Wind and Sandblast Damage by Grain Sorghum Plants1
Authors: Armbrust D. V. 
Published: July 2010

AbstractYield depression due to physical damage by wind and windblown soil (sandblast damage) is well known. Less well known is the reason for the yield reductions by sandblast damage. The objective of the research was to determine if this yield depression was due to a simple loss of photosynthetically active leaf tissue or to physiological changes within the plant.Physiological responses of growth chamber grown RS 626 grain sorghum (Sorghum bicolor L. Moench) to injury by wind (13.4 m/sec), wind plus sand (10, 20, 30, 40, 50, 60, and 70 kg), and partial defoliation (removal of the distal one‐fourth and one‐half of each leaf) were evaluated. Wind and wind plus sand treatments were conducted in a wind tunnel. Net photosynthesis, dark respiration, total chlorophyll, dry weight, and leaf area were determined 1, 3, and 7 days after treatment.Dry weight production increased at low sand levels (< 30 kg) and decreased with higher sand exposure. Reduced growth of sandblasted grain sorghum is caused by loss of viable leaf tissue and physiological changes, which are mainly reduced photosynthesis and increased respiration. It is not clear from this study if these changes result from partial defoliation, short‐term high‐intensity moisture stress, or a combination of both.
Feed Quality of Hay Containing Perennial Broadleaf Weeds1
Authors: Dutt T. E. , Harvey R. G. , Fawcett R. S. 
Published: July 2010

AbstractMany studies have been conducted to determine how to control perennial broadleaf weeds in alfalfa (Medicago sativa L.) swards, but little information is available on the effects of these weeds on forage utilization by ruminant animals. Therefore, alfalfa or alfalfa‐grass mixtures infested with yellow rocket (Barbarea vulgaris R. Br.), white cockle (Lychnis alba Mill.), and dandelion (Taraxacum officinale Weber.) were treated with herbicides to provide differences in weed composition of harvested forage. Differences in intake, digestibility, and nutrituve value index between weedy and weed‐free forages were determined by feeding hay from the various herbicide treatments to goats in stall trials. Observations indicated that dandelion and white cockle were palatable and yellow rocket was unpalatable.Animal intake, in vivo digestibility, and nutritive value index werereduced by an infestation of yellow rocket but not by white cockle in alfalfa‐grass mixtures. Crude protein concentration and in vitro digestibility were highest in dandelion, intermediate in white cockle, and lowest in yellow rocket. Based on the small differences in quality observed between most of the weedy and weed‐free forages, we concluded that only yellow rocket would reduce the feed value of hay for ruminant animals.
Interaction of Atmospheric CO2 Enrichment and Irradiance on Plant Growth1
Authors: Sionit Nasser , Hellmers H. , Strain B. R. 
Published: July 2010

AbstractAtmospheric carbon dioxide and irradiance are important factors affecting growth and yield of plants. Due to the wide variation in irradiance in natural plant stands and the reportedly increasing carbon dioxide concentration in the global atmosphere, it is essential to study the interacting effects of these factors on the growth and production of crop plants. Growth analysis techniques were used to study the interaction of atmospheric CO2 concentration (350 and 675 µl/l) and photosynthetic photon flux density (PPFD) (600 and 1200 µEM−2 s−1)on four species (including both seed and root crops) grown in controlled environment chambers of the Duke University Phytotron. The plants were soybean (Glycine max L. Merr.), radish (Raphanus sativus L.), sugarbeet (Beta vulgaris L.), and corn (Zea mays L.). Total dry matter production increased in all species of plants and at all growth stages with both increased CO2 concentration and PPFD levels, and the maximum dry matter was produced at the highest combined levels of CO2 and PPFD. The dry weight increase varied between the different species and between plant parts within a species. High levels of CO2 and PPFD caused a greater increase in net assimilation rate in the plants during early growth stages than in later stages because the first two or three young, rapidly growing leaves were very efficient photosynthetic organs. A high CO2 or PPFD level resulted in decreasing leaf area ratios with increasing plant age for all the species due to a rapid increase in stem and root growth later in fruit production, and to a decreasing specific leaf area.Corn, having the C4 pathway of photosynthesis, showed less response to increased CO2 and PPFD than the three C3 species. Increasing the atmospheric CO2 concentration from 350 to 675 µl/liter at low and high PPFD levels produced dry matter increases of 72.7 and 76.4%, respectively, in soybean, and 18.9 and 18.6%, respectively, in corn at 50 days after planting. None of the species tested were light saturated at levels available in the standard fluorescent and incandescent lighting as is shown by the increased growth when higher PPFD levels were obtained with a combination of multivapor and sodium lamps.
Variability of Reflectance Measurements with Sensor Altitude and Canopy Type1
Authors: Daughtry C. S. T. , Vanderbilt V. C. , Pollara V. J. 
Published: July 2010

AbstractUse of portable, ground‐based sensors for measuring crop reflectance has created a need for comparable and reliable measurement procedures capable of providing calibrated and reproducible canopy reflectance data. In this field experiment we determined how canopy reflectance varies as a function of sensor altitude above the crop and what minimum altitude is needed to acquire repeatable reflectance measurements with a 15 degree field of view instrument. Data were acquired in 1979 on three canopies grown on a Typic Argiaquoll; mature corn (Zea mays L.) planted in 76 cm rows, mature soybeans [Glycine mays (L.) Merr.] planted in 96 cm rows with 71% soil cover, and mature soybeans planted in 76 cm rows with 100% soil cover. Spectral data were acquired using a Landsat band radiometer (Exotech 100) at 10 altitudes ranging from 0.2 to 10 m above the canopy. At each altitude, measurements were taken at 15‐cm intervals along a 2.0 m transect perpendicular to the crop row direction.The variance of reflectance factor measurements at low altitudes was attributable to row effects which disappeared at higher altitudes where the sensor integrated across several rows. The coefficient of variation of reflectance factor in both visible and near infrared bands decreased exponentially as the sensor was elevated. Systematic sampling (at odd multiples of 0.5 times the row spacing interval) required fewer measurements than simple random sampling over row crop canopies. Extreme care must be exercised in analyzing and interpreting data acquired at sensor altitudes where the diameter of the sensor's FOV at the top of the canopy is smaller than several multiples of the row spacing.