bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seeding Sorghum × Sudangrass Hybrids into Tall Fescue Sod1
Authors: Hart Richard H. , Retzer Henry J. , Dudley Richard F. , Carlson G. E. 
Published: July 2010

AbstractSorghum × sudangrass hybrids (Sorghum bicolor L. Moench × Sorghum sudanense P. Stapf.) were seeded into tall fescue (Festuca arundinacea Schreb.) sod, which had been temporarily suppressed with paraquat4 (l,l'‐dimethyl‐4,4'‐bipyridinium dichloride). Sod‐seeded De‐Kalb ‘Sudax SX‐12’, with N fertilizer banded under the seed, produced as much forage as conventionally seeded Sudax. Sod‐seeded ‘Sudax SX‐11’ and SX‐12, with N broadcast at seeding, produced less forage than conventionally seeded Sudax, unless enough paraquat was applied to damage tall fescue permanently. Combined yield of tall fescue and sod‐seeded Sudax, under the best management, was about 60% greater than yields of either fescue or Sudax alone.
Method for Estimation of Tannin in Grain Sorghum1
Authors: Burns Robert E. 
Published: July 2010

AbstractThe acidified vanillin method of tannin analysis, widely used for forage crops, was modified to permit rapid estimation of relative tannin content of grain sorghum [Sorghum bicolor (L.) Moench]. The method involves overnight extraction of ground grain with methanol at room temperature. An aliquot of the extract is added to a solution of vanillin and hydrochloric acid and the resultant color is read on a colorimeter at 500‐525 mµ The reagent is specific for astringent compounds in plants and the results were highly correlated with digestibility.
A Sunfleck Theory for Plant Canopies I. Lengths of Sunlit Segments along a Transect1
Authors: Miller E. E. , Norman J. M. 
Published: July 2010

AbstractThe size distribution of sunflecks under a plant canopy can be represented by the length distribution of sunlit segments along a straight‐line transect drawn under the canopy. A mathematical connection is deduced between this sunlit‐length distribution and the probability, as a function of length, that a short line placed randomly under the canopy will be everywhere in sunlight. In turn, this probability distribution is deduced for randomly‐placed leaves, from which the above‐mentioned connection yields the desired sunlit‐length distribution. In subsequent papers this basic result will be used to predict the effect of penumbra — fuzzy shadow edges caused by the finite angular size of the sun — upon the light intensity distributions within or beneath canopies, as a function of leaf size, shape, height, density, and orientation.
Forage Characteristics Limiting Animal Performance on Warm‐season Perennial Grasses1
Authors: Duble R. L. , Lancaster J. A. , Holt E. C. 
Published: July 2010

AbstractChemical and in vitro characteristics of six perennial summer grasses {common, ‘Coastal’ and ‘Coastcross‐1’ bermudagrasses [Cynodon dactylon (L.) Pers.]; ‘Pensacola’ bahiagrass [Paspalum notatum Flugge]; common weeping lovegrass [Eragrostis curvula (Schrad.) Nees.]; and ‘Kleingrass 75’ [Panicum coloratum L.]} were determined to identify factors limiting the performance of grazing animals. In vitro dry‐matter digestibility (IVDMD), cell wall content (CWC), acid‐detergent fiber (ADF), acid‐detergent lignin (ADL), silica, and in vitro cell‐wall digestibility (IVCWD) were determined for samples of available forage taken at 14‐day intervals. Animal performance was obtained from yearling heifers grazing established stands of each grass. Available forage was estimated from strips harvested from each pasture at 2‐ to 4‐week intervals. Animal performance was significantly correlated (r = 0.85**) with available forage when dry‐matter digestibility was relatively uniform. As IVDMD of available forage decreased, more available forage was required to reach maximum average daily gain (ADG). Also, as IVDMD decreased, maximum ADG decreased. The CWC of the grasses ranged from 45 to 82% with cell wall digestibility ranging from 82 to 36%, respectively. CWC and IVDMD were significantly correlated with animal performance (r = —0.80**, and 0.78**, respectively). Cell wall digestibility calculated from Van Soest's “summative equation” significantly over‐estimated IVCWD. Lignification was one factor limiting cell wall digestibility (r = —0.76**) and in Coastcross‐1 bermudagrass and Pensacola bahiagrass silica was as important as lignin. CWC and IVCWD could be used to accurately predict IVDMD in Kleingrass 75 (r = —0.96** and 0.95** respectively). High lignin and/or silica content of available forage was associated with poor animal perfortnance on all grasses.
Crop Response to Excessive Zinc Fertilization of Alkaline Soil1
Authors: Boawn Louis C. , Rasmussen P. E. 
Published: July 2010

AbstractThe objective of this research was to evaluate the tolerance of economic plant species to excessive levels of available Zn in the soil.Fifteen field crop and three vegetable crop species were grown under uniform conditions in a growth chamber in alkaline soil treated with 10, 100, 200, 300, 400, and 500 ppm Zn. Response was evaluated in terms of dry matter yield decrease (YD) and Zn concentration in tops. Grass species were most sensitive and had maximum YD's greater than 40%. Alfalfa (Medicago saliva L.), Alaska pea (Pisuni sativum L.), tomato (Lycopersicon esculentum Mill.), lettuce (Latuca saliva L.), spinach (Spinacia oleracea), and sugarbeet (Beta vulgaris L.) had YD's between 20 and 40%. Field bean (Phaseolus vulgaris L.), snap bean, russet potato (Solanum tuberosum L.), white potato, clover (Trifolium repens L.), and Perfection pea (Pisum sativum L.) did not undergo a significant YD.Zinc concentrations in tops associated with a 20% YD ranged from 240 ppm for field bean to 740 ppm for sugarbeet, with most crops falling in a 400 to 600‐ppm range. The most sensitive species tolerated Zn additions of 200 to 300 ppm before undergoing a significant YD.Crops that underwent a significant YD because of excess Zn were stunted but showed no discoloration, malformation, or necrosis indicative of a direct metal toxicity.
Growth Stages of Sorghum [Sorghum bicolor, (L.) Moench.]1
Authors: Vanderlip R. L. , Reeves H. E. 
Published: July 2010

AbstractResearch with grain sorghum often involves sampling several times during the growth cycle. Samplings often are designated by calendar date, days after planting or emergence, or plant height. Often these bear little or no actual relationship to the morphological or physiological age or status of the plant. Although certain stages of sorghum growth are fairly well established, the growth cycle of sorghum has not been fully described. Therefore, a standard set of growth stages needs to be defined. Based on detailed studies of grain sorghum hybrids of different maturities, the following ten stages of development have been defined and illustrated: emergence, three‐leaf, five‐leaf, growing‐point, differentiation, final leaf visible in whorl, boot, half‐bloom, soft dough, hard dough, and physiological maturity. These stages are suggested as standards to describe the timing of sampling or treating sorghum.
Selenium Accumulation in a Collection of Atriplex Species
Authors: Davis A. M. 
Published: July 2010

AbstractStone native American Atriplex species are known Se accumulators. This study was undertaken to determine the Se accumulation characteristics of some non‐North American species.Twenty‐three accessions, including 15 species from 8 countries, were grown in Se‐enriched soil in the greenhouse and the Se content of the aboveground portions was determined by AOAC methods. Atriplex canescens James accessions were higher in total Se (160 ppm plus) than the other species tested. All accessions accumulated Se at potentially toxic levels from the enriched soil.
Adaptability of Maize to High Soil Water Conditions1
Authors: Das D. K. , Jat R. L. 
Published: July 2010

AbstractMaize (Zea mays L.) plants were grown in furrows and ridges in a lowlying sandy clay loam soil under high soil‐water conditions. Root porosities of 44‐day‐old plants were studied. The investigation was undertaken to determine varieties that could adjust to such environment through internal aeration.Varietal differences were found in the percentage of air space of roots. Plants grown in furrows had higher root porosities than those grown in ridges. Six varieties studied were ‘Kissan,’ ‘Deccan,’ ‘Jawahar,’ ‘Ganga 5,’ ‘Vikram,’ and ‘Sona.’ The first two may adjust better to excess soil water due to greater internal aeration resulting from increased root porosities.
Comparison of Two Simple Methods of Chlorine Analysis in Plant Materials1
Authors: Adriano D. C. , Pratt P. F. , Holtzclaw K. M. 
Published: July 2010

AbstractChloride determinations obtained with an automatic Cl titrator compare very favorably with the results obtained using an electrometric method. Extraction of Cl from plant materials with acids can be done either by shaking samples for 10 min or allowing them to stand overnight. One technician can analyze about 40 to 60 plant samples per day with the electrometric method and 80 to 100 plant samples or 100 to 170 soil extracts or water samples per day with the automatic Cl titrator.
Water Relations and Growth of Cotton in Drying Soil1
Authors: Klepper Betty , Taylor H. M. , Huck M. G. , Fiscus E. L. 
Published: July 2010

AbstractTwo 70‐day‐old cotton plants (Gossypium hirsutum L. ‘Auburn 7‐683’) were subjected to a 26‐day drying cycle at the Auburn rhizotron in order to quantitatively study water relations and growth of both root and shoot as the soil dried. Measurements were made of rooting density changes; stem diameter and height increase; and soil water content (neutron meter), soil water potential (thermocouple psychrometer), and plant water potential (pressure chamber). Marked diurnal flurtuations in plant hydration and soil water potential were observed, especially during the middle of the drying cycle. Plant height increase and stem diameter growth slowed drastically after 17 days even though 35% of the root system was in soil wetter than −1 bar and the plant was rehydrating to a water potential of −3 to −5 bars. Plant water potential in the early morning did not equilibrate with the water potential of the wettest horizon of soil.The pattern of rooting with depth shifted during drying; initially, there were more roots in the upper layers of soil but, as a result of death of old roots in the top layers and production of new roots in the lower horizons of soil, rooting density increased with depth by the end of the drought. Cotton plants grown at the same time in a similar profile that was maintained moist did not show this reversal in rooting density.
“Reductants” Released by Roots of Fe‐Deficient Soybeans1
Authors: Brown J. C. , Ambler J. E. 
Published: July 2010

AbstractIron‐stressed (deficient) ‘Hawkeye’ (HA) releases more “reductant” into nutrient solutions than PI‐54619‐5‐1 (PI) soybean [Glycine max (L.) Merrill] roots. These two plants differ in their response to Fe stress and their susceptibility to Fe chlorosis. The objective of this study was to characterize the “reductant” and to determine its role in the uptake of Fe by HA and PI soybeans.Reducing capacity of the ‘reductant’ was determined by its ability to reduce ferric to ferrous iron. Fe2+ was measured using 2,4,6,‐tripyrldyl‐s‐triazine (TPTZ) to form the color complex Fe2+(TPTZ)2. The reductant compounds were separated using paper chromatography (BAW‐4:1:5) and located on the paper as prussian blue spots after the papers were placed in ferricyanide‐ferrichloride solutions.Reductant from 16 HA reduced 90 μmoles (Fe3+ to Fe2+) compared to 5 μmoles for PI soybeans. The chelating agents HEDTA and DTPA (3 μmoles) decreased the reducing capacity from 1.8 μumoles Fe2+/ml concentrated reductant to 0.2 μmoles/ml. Adding more reductant partially overcome the interfering effects of the chelating agents.Adding the concentrated reductant to nutrient solutions increased the amount of Fe~+ iron in solution, but it did not increase the uptake of Fe by the plant. Something other than reductant in nutrient solution appears to be the controlling factor in the uptake of Fe by PI and HA soybeans. We believe the reductant can aid in releasing Fe from chelating agents to the root and that it can maintain Fe2+ in the reduced state in the root. The latter may be its more important role in Fe nutrition.
Water Stress Relations of the Potato Plant under Field Conditions1
Authors: Epstein Eliot , Grant W. J. 
Published: July 2010

AbstractPotatoes (Solanum tuberosum L.) grown in northern Maine are often subjected to extensive periods of drought. The objective of this study was to examine the physiological response of potatoes to soil water stress.Relative water content, leaf diffusive resistance, and tuber water potential of two potato varieties were measured under irrigated and nonirrigated conditions. There were pronounced differences in relative water content, leaf diffusive resistance, and tuber water potential as a result of irrigation. Relative water content (RWC) of plant leaves correlated well with soil water potential but poorly with leaf diffusive resistance. The two potato varieties differed in RWC when soil water potential was high.Tuber water potential correlated well with RWC and soil water potential. Similarity between tuber water potential and the RWC data suggested that the potato plant exhibits water stress when the soil water potential drops below −0.25 bar.
Effect of Nitrogen Fixation by Legumes on Soil Acidity1
Authors: Nyatsanga Titus , Pierre W. H. 
Published: July 2010

AbstractThe objectives of this study were to determine the quantitative effect of symbiotic N fixation on soil acidity and to compare this effect with the theoretical amount of acidity that should be produced on the basis of the excess‐base and N content of the crops. Alfalfa (Medicago sativa L.) and soybeans (Glycine max (L.) Merr.) were grown on two soils in a greenhouse experiment. The amount of acidity that developed was determined by measuring the amounts of calcium carbonate required to bring the pH of the cropped soils back to those of the uncropped. The excess‐base and N contents of the plants were obtained by analyzing the tops, stubbles, and roots of alfalfa and the tops, roots, and nodules of soybeans. The amount of N fixed was calculated from the differences between the total N found in the crops and the nitrate accumulation that took place in the uncropped soils during the experimental period. Some information was also obtained on the uptake of N from one of the soils by growing a nonnodulating strain of soybeans.Under the intensive cropping in the greenhouse the amount of N fixed by ‘Vernal’ alfalfa, during a growth period of 167 days (3 cuttings) or by soybeans (Glycine max, T201 and T202, U. S. Regional Soybean Laboratory) during a growth period of 67 to 73 days was sufficient to lower the pH of the soils by more than 1.0 pH unit and to require the addition of up to 2000 ppm of CaCO3 to bring the soils back to their original pH.On the basis of the data obtained, N fixation from an annual yield of 10 metric tons/ha (4.6 tons/acre) of alfalfa would produce acidity in the soil equivalent to 600 kg CaCO3/ha or 535 lb/acre. Relatively good agreement was obtained between the amount of acidity developed in the soils by alfalfa and soybeans and the theoretical amounts calculated from the N and excess‐base contents of the plants. Thus, the acidity produced in soils by N fixation is of considerable significance under certain cropping conditions. It is suggested that it may also have been an important factor in soil genesis and development.
Evapotranspiration by Subirrigated Alfalfa and Pasture in the East Central Great Plains1
Authors: Blad Blaine L. , Rosenberg Norman J. 
Published: July 2010

AbstractEvapotranspiration (ET) rates from subirrigated alfalfa (Medicago sativa L.) pasture were obtained to provide an estimation of the upper and lower limits of water demand for crops growing in climatic regions characterized by strong advection of sensible heat. Results of this study showed that ET rates were 20 to 25% lower in pasture than in alfalfa. These differences are much larger than any previously reported in the literature.Advected sensible heat supplied about 20% of the total energy consumed in the latent heat flux (LE) from alfalfa for the entire study and as much as 40% on certain days. In the pasture, however, with few exceptions, sensible heat was generated rather than consumed.
Effect of Soil Water Stress at Various Growth Stages on Soybean Yield1
Authors: Doss B. D. , Pearson R. W. , Rogers Howard T. 
Published: July 2010

AbstractConventional irrigation experiments and rainfall distribution‐yield studies have indicated that insufficient water during flowering and pod‐fill stages frequently limits yields of soybeans (Glycine max (L.) Merr.). In this 3‐year experiment, field plot covers were used to control rainfall and water stress was imposed on plants at various stages of growth to determine more specifically the critical periods for irrigating soybeans for maximum yields. Soil water regimes ranged from a limited supply (10% available soil water) to adequate water (50% available) during the entire growing season. More bean production was obtained from water applied after full bloom than earlier. The pod‐fill stage, from August 15 to September 20 for ‘Bragg’ soybeans at Thorsby, Alabama, was the critical time for adequate water for maximum yields. Yields from adequately watered soybeans were 540 to 1,040 kg/ha, or 24 to 55%, greater than where water was limited throughout the growing season. Highest yield obtained under the best water regime was 3,320 kg/ha. Conditions limiting yields were not obvious.
Development and Distribution of the Corn Root System Under Field Conditions1
Authors: Mengel D. B. , Barber S. A. 
Published: July 2010

AbstractThe rate of corn (Zea mays L.) root growth in the field and root distribution in the soil as related to stage of plant growth has not been studied in detail. To obtain more information we measured the length, fresh weight, and distribution of corn roots at time intervals between planting and harvest in 1970 and 1971. The study was made on corn growing on Chalmers silt loam soil at Lafayette, Indiana. Grain yields were 6,160 kg/ ha in 1970 and 11,700 kg/ha in 1971.Root length and fresh weight increased rapidly for 80 days following planting, remained relatively constant for 14 days, and then decreased rapidly when the plants were in the reproductive stage. A maximum root density of 4.1 cm/cm3 occurred in the 0 to 15 cm zone at 79 days. The lower soil zones reached maximum root density 1 to 2 weeks later than in the 0 to 15 cm zone. Root density in the 0 to 15 cm zone was greater in cores taken midway between plants in the row than at other locations. Maximum root length was 153 cm/cm2 of surface area at 86 days.
Root Development and Growth Response of Corn Following Mulching, Cultivation, or Interrow Compaction1
Authors: Chaudhary M. R. , Prihar S. S. 
Published: July 2010

AbstractField studies were conducted to determine the effect of interrow management on root growth and rooting pattern in corn (Zea mays L.) and to relate these with changes in soil environment. Four cultural treatments, 1) control 2) 5‐cm deep postplanting cultivation, 3) 2‐cm thick straw mulch, and 4) interrow compaction, were established on sandy loam and loamy sand soils during 1970 and 1971. Straw mulch and cultivation enhanced root growth in the upper 15 cm of soil and increased the lateral spread of roots both years. The mulch treatment had less roots than the control below 15 cm. The cultivated plants had more symmetric root distribution. Interrow compaction inhibited lateral spread of roots in the surface layers and caused downward growth of roots. At the 5‐cm depth straw mulch reduced the maximum soil temperature by 2.6 C in 1970 and 2.3 to 6.3 C in 1971. Greater lateral spread and enhanced root growth in the surface layers of mulched plots were associated with reduction of soil temperature and reduction of moisture losses and resulted in better plant growth and higher yield.
Prediction of Spring Wheat Yields from Temperature and Precipitation Data1
Authors: Haun J. R. 
Published: July 2010

AbstractAs a consequence of studies indicating that daily plant growth rate can be used to establish specific, numerical, growth‐environment relationships, it has been found that these relationships may be used in the prediction of yields. Design of a prediction system was based on the hypothesis that plant growth rate, as reflected in cumulative growth during the formative portion of plant development, correlated with yield. To insure accessibility of sufficient data, environmental variables were limited to temperature and precipitation because these are generally the only variables published for long periods of time over broad geographical areas. Estimated soil moisture was calculated by the Thornthwaite‐Mather method.Significant lags were found in plant response to environmental variables. Lengths of lag periods also changed during the season. Thus, two prediction equations were used to accommodate these changes and they were applied to the temperature and precipitation records. Resulting cumulative growth values and data representing pre‐season moisture conditions were used as independent variables on which yield was regressed to provide a prediction equation for yield.The system, involving two equations for growth prediction and one equation for yield, was tested on unrelated (data not used in the formulation of equations) weather and yield data for major spring wheat (Triticum aestivum L. em. Thell.) production areas in Canada and the U.S.S.R. The close agreement of predicted yields with actual recorded yields indicates that the use of the system is a promising approach for predicting yields and evaluating the influence of temperature and precipitation on yields.
Mn and B Effects on Micronutrients and P in Cotton1
Authors: Ohki K. 
Published: July 2010

AbstractInteractions involving macro and micronutrients modify plant growth, as indicated by induced deficiencies or toxicities and growth reductions. The objective of this study was to determine the influence of Mn and B and their interactions on micronutrients in leaf tissues of upland cotton (Gossypium hirsutum L.). A 2 ✕ 11 factorial design included two B levels of 35 and 500 µg/liter and 11 Mn levels, varying from 0 to 4000 µg/liter in nutrient solution under greenhouse conditions.In blade 3, Mn tissue concentration less than the 10 µg/g critical level induced high Zn concentration of 127 µg/g in leaf tissue. As Mn concentration approached the critcial level, Zn concentrations decreased to 33 µg/g and remained constant with increasing Mn to 247 µg/g. Copper concentration was independent of Mn concentration. However, the reciprocal Mn‐Fe relationship was apparent where Mn concentrations of 4 and 247 µg/g were associated with Fe concentrations of 270 and 51 µg/g, respectively. Manganese nutrition had a small but significant influence on P concentrations where P concentrations of 2.37 and 1.84% were associated with Mn concentrations of 8 and 210 µg/g, respectively. The influence of B levels on micronutrient concentration in leaf tissue was not consistent. Low B induced lower Mn concentrations than did adequate B in young and recently matured tissue, whereas no effect of B levels on Mn concentration was evident in older leaf tissue. Low B induced a small but significantly lower Zn concentration in recently matured blades, while no effect of B nutrition on Cu was observed. However, low B induced higher Fe concentrations in old blades than did adequate B.