bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Techniques for Measuring Drought Avoidance in Cereal Seedlings1
Authors: Salim M. H. , Todd Glenn W. , Stutte C. A. 
Published: July 2010

AbstractWater retention, water resaturation values, and survival were determined on seven wheat, five barley and four oat cultivars after either whole plants or cut leaf sections were dried over either CaCl2 or glycerol solutions giving known relative humidities. Water retention of these cereals (with one exception) was not affected by plant age at time of measurement (10‐ to 28‐day‐old plants). Water retention was significantly increased by drought hardening in two wheat and one barley cultivars, while sand versus soil culture gave no consistent effects. Water retention of detached leaves even with eight replicates did not give good differentiation among wheat cultivars. Water retention of intact plants following exposure to low vapor pressure was correlated with survival‐survival was greater in barley and wheat than in oats after the tissue had reached a given water level. Tetrazolium ratings decreased sharply in leaves in which the relative water content was lowered to values of 30% or less. Resaturation values were strongly correlated with relative water content after drying of five wheat and one rye cultivars, indicating that drought avoidance is of greater importance than tolerance among these plants.
Daily Variation in Carbohydrate Content of Selected Forage Crops1
Authors: Holt D. A. , Hilst A. R. 
Published: July 2010

AbstractDaily variation in percentages of water‐soluble carbohydrates, total nonstructural( 0.2 N H2SO4 soluble) carbohydrates, and differences between these, representing nonstructural polysaccharides exclusive of fructosan, in alfalfa (Medicago sativa), Kentucky bluegrass (Poa pratensis), bromegrass (Bromus inermis), and tall fescue (Festuca arundinacea) were investigated.Water soluble carbohydrate percentages in alfalfa followed a curvilinear diurnal trend from a low at 6:00 A.M. to maximum levels at 12:00 noon and decreased slightly by 6:00 P.M. Nonstructural polysaccharide content followed a nonlinear daily trend with the most rapid increase occurring in the afternoon.The grasses underwent linear increases in water soluble carbohydrate percentages from 6:00 A.M. to 6:00 P.M. Likewise, the nonstructural polysaccharide content of the grasses followed an increasing linear trend in the daytime. Nonstructural polysaccharide content increased more rapidly in bromegrass and tall fescue than in bluegrass. Variation in water‐soluble carbohydrate content accounted for almost all of the daily variation in total nonstructural carbohydrate content of bluegrass.Alfalfa and bluegrass grown under low potassium nutrition had significantly higher water soluble carbohydrate percentages than those growing under high potassium nutrition.
Weed Control and Plant Residue Maintenance with Various Tillage Treatments in a Winter Wheat‐Fallow Rotation1
Authors: Fenster C. R. , Domingo C. E. , Burnside O. C. 
Published: July 2010

AbstractLate spring tillage gave the most effective weed control in a winter wheat (Triticum aestivum L.)‐fallow rotation. Downy brome (Bromus tectorum L.) populations in winter wheat on May 1 following plow, one‐way, and sweep plow fallow treatments were 11, 22, and 24 plants per square meter, respectively. Tillages only in July or August with the sweep plow or one‐way did not effectively control downy brome in the subsequent wheat crop. Yields of winter wheat were highest on the mold‐board plow plots followed by one‐way and sweep plow plots tilled in July and again in April. July tillages with the sweep plow or one‐way resulted in the lowest winter wheat yields. During the fallow year, weed control in June was best on moldboard‐plowed plots followed by May tillages with the sweep plow and the one‐way. Quantities of plant residues on the soil surface prior to seeding winter wheat on sweep plow, one‐way, and plot treatments were 896, 728, and 54 kg/ha, respectively.
Bray and Morgan Soil Extractants Modified for Testing Acid Soils from Different Parent Materials1
Authors: McIntosh Jerry L. 
Published: July 2010

AbstractBray and Morgan soil extracting solutions were modified to increase their usefulness in testing acidic soils of different parent materials and ranges of fertility.The Morgan extractant was changed by substituting NH4 for Na. For equilibration type extractions, NH4 removes more K from clay soils than does Na. Although the Morgan extractant satisfactorily removes K from sandy soils, its inability to remove a proportionate amount of K from clay soils makes it unsatisfactory for routine testing in areas where soils are variable.The Morgan extractant removes some of the readily available P but gives little indication of the reserve or accumulated P in acid soils. But if NH4F is added to the modified Morgan extractant to provide an 0.03 N F solution, a second extraction will give a measure of the accumulated P reserve. These two extractions made upon the same sample, or a second sample of the same soil, provide a better basis for assessing P availability in soils than either alone.If the first extraction for the more available P is not desired, P and the more commonly determined exchangeable bases can be measured in a single extraction by the proposed solution of NH4OAc + NH4F. This procedure is recommended for states where two separate extractions presently are made for P and K.
Tolerance of Sorghum bicolor (L.) Moench to Several Herbicides1
Authors: Miller F. R. , Bovey R. W. 
Published: July 2010

AbstractWe evaluated 40 varieties of Sorghum bicolor (L.) Moench representing 27 diverse subclassification groups for tolerance to herbicides. Sorghums studied included commercial varieties from the continental United States and cultivars which have not reached the temperate zone. These sorghums were developed or originated in the USA, India, China and seven African countries.Clay soil and sand were treated with 3.2, 9.6 and 28.8 ppm of 2‐chloro‐4,6‐bis(isopropylamino,‐s‐triazine (propazine), 3‐(hexahydro‐4,7‐methanoindan‐5‐yl)‐lmethylurea (norea), 2‐tert butylamino‐4‐ethylamino‐6‐methylthio‐s‐triazine (GS‐14260), 3‐(3,4‐dichlorophenyl)‐I‐methoxy‐l‐methylurea (linuron) and 2‐chloro‐N‐isopropylacetanilide (propachlor).Herbicides differed significantly in the amount of injury caused to sorghum. The following relationships were found in order of increasing damage: propachlor, 10.5%; propazine, 35.7%; norea, 50.0%; GS‐14260, 59.5%; and linuron, 72.4%.Sorghum varieties which produced well in untreated herbicide media also produced best in herbicide‐treated media. Varieties ‘IS 7363’ and ‘PI 285042’ were consistently most tolerant regardless of herbicide. Varieties that ranked in the top 12.5% of the control were not killed by the various herbicides unless all varieties were destroyed.Response to herbicides does not appear to be inherited simply, although differences in tolerance do exist. Dry weight frequency distributions for response to each herbicide indicate near normal curves. Tolerance to herbicides was most evident in the caudatum, durra, and conspicuum groups. Herbicide tolerance was more pronounced in sorghums from equatorial Africa than from the areas where varieties have been developed through intensive breeding programs.
Plant Moisture Stress: A Portable Freezing‐Point Meter Compared with the Psychrometer1
Authors: Cary J. W. , Fisher H. D. 
Published: July 2010

AbstractA small portable instrument for measuring the freezing‐point depression of plant tissue has been developed for field use. The instrument is easy to operate and can be constructed from materials costing less than $100.Moisture stress measurements made with the freezing‐point meter on a variety of plants were compared with vapor pressure psychrometer measurements. Variation between duplicates in the freezing point averaged 1.2 bars, but differences between stress measurements made with the psychrometer and freezing‐point instrument averaged 2.6 bars.
Relationship of Soil Texture to Sulfur Oxidation1
Authors: Rehm G. W. , Caldwell A. C. 
Published: July 2010

AbstractThe oxidation of elemental sulfur added to 52 soils of various textures was measured after three incubation periods. Although on the average more of the added S was oxidized in the coarse textured soils, statistical analysis showed that soil texture had no effect on S oxidation for any of the incubation periods. In general, the major portion of the S oxidation occured during the first 30 days.
Mineral Deficiency Symptoms in Loblolly Pine Seedlings
Authors: Lyle E. S. 
Published: July 2010

AbstractLoblolly pine (Pinus taeda L.) seedlings were grown in nutrient solutions each deficient in one of the essential elements. A description of observed deficiency symptoms is given for each essential element. Coloration symptoms are described by means of Munsell color charts and were tested for significance. Munsell color charts proved to be practical and consistent for color descriptions. Symptoms that proved to be unique were used in the development of a dichotomous key for the identification of essential element deficiencies.
Effect of Population and Row Spacing on the Performance of Four Corn (Zea mays L.) Hybrids1
Authors: Giesbrecht John 
Published: July 2010

AbstractFour early corn hybrids were grown at the four populations of 30,000, 45,000, 60,000, and 75,000 plants per hectare, at each of the four spacings of 50, 65, 80, and 95 cm between rows. The row spacings did not affect grain yield. However, each increase in population produced a substantial increase in grain yield. Varieties differed significantly in their yield response to increased plant populations. The later maturing, taller hybrids were adapted better to the competition in high populations than were the earlier hybrids.
Nutritional Requirements of Poa annua L.1
Authors: Juska F. V. , Hanson A. A. 
Published: July 2010

AbstractPot experiments were conducted in the greenhouse to determine the nutritional requirements of Poa annua. Total top yield was greater for annual bluegrass grown in silt loam soil than in loamy sand. In loamy sand a large decrease in clippings, crowns, and roots was obtained at a pH of 4.5 compared to pH 6.5. Differences between pH levels were not significant in the silt loam soil. N, P, and K contributed most to top growth in the order mentioned. Results of this study indicate that annual bluegrass has the ability to grow better than Kentucky bluegrass, Poa pratensis L., at a low pH level in a silt loam soil.
Root Air Space Measurements by a Pycnometer Method1
Authors: Jensen C. R. , Luxmoore R. J. , VanGundy S. D. , Stolzy L. H. 
Published: July 2010

AbstractThe air space fraction, or porosity, of plant roots is important to their internal aeration. Root porosity can be calculated from the following measurements: the weight of a sample of the roots in a pycnometer bottle filled with water; the weight of the root sample alone; the weight of the homogenate after ball milling the sample; and the weight of the bottle filled with water only. Results are variable and a mean of 10 samples must be obtained.
Continuous Corn by the No‐Tillage and Conventional Tillage Methods: A Six‐Year Comparison1
Authors: Shear G. M. , Moschler W. W. 
Published: July 2010

AbstractCorn (Zea mays L.) was grown on a loam soil on the same plots annually for a period of 6 years, comparing no tillage, tillage in alternate years, and conventional tillage. Equal annual applications of phosphate mixed in the tilled soil and applied to the surface of untilled soil resulted in more available phosphorus accumulation in the upper 5 cm of the untilled soil. The total amount of available phosphorus for the upper 20 cm of soil was greater in untilled soil despite the fact that available phosphorus was lower than in tilled soil in two of the 5‐cm increments below the surface layer. Potassium availability was not affected by tillage or method of application. Soil compaction after six years as based on bulk density showed no difference related to tillage.The maintenance of high yields of corn in successive years without tillage was shown. There was no benefit from tillage in alternate years as compared with no tillage. An average increase in corn grain yields and equal or better stover yields from no tillage as compared with conventional tillage was found. The need for more frequent liming with the no‐tillage method was demonstrated.
Evaluation of Rotation Grazed Pastures from Esophageal and Hand Gathered Forage Samples1
Authors: Heinemann W. W. , Russel T. S. 
Published: July 2010

AbstractA study was conducted to determine changes in certain characteristics of rotation grazed irrigated orchardgrass‐alfalfa pastures. Samples for botanical composition and selected proximate components were taken from esophageal fistulated animals and by hand collection. Botanical composition at the beginning of each rotation from the esophageal samples was similar to that of the hand samples. However, at the end of the rotations the esophageal samples had a grass‐alfalfa ratio of 6:1 while the hand samples had a ratio of 3:2. Dry matter digestibility was similar each year but first‐day samples were more highly digestible than last‐day samples. for a given date there was no difference between dry matter digestibilities of hand and esophageal samples. First‐day samples had higher protein levels than last‐day samples. There was more protein in the esophageal samples than in the hand samples but it was not as digestible. The net effect was that by both methods the estimate of digestible protein intake per unit weight of dry matter was approximately equal. Crude fiber was higher at the end of a rotation than at the beginning and the esophageal samples contained less crude fiber than the hand samples. Crude fiber digestibility declined in both kinds of samples from the first to last day of grazing a rotation. Total digestible crude fiber intake per unit weight of dry matter intake was not the same for the two methods.
Effect of the d2 Dwarf Gene on the Forage Yield and Quality of Pearl Millet1
Authors: Burton Glen W. , Monson W. G. , Johnson J. C. , Lowrey R. S. , Chapman Hollis D. , Marchant W. H. 
Published: July 2010

AbstractNear‐isogenic dwarf and tall pearl millet, Pennisetum typhoides (Burm.) Stapf and C. E. Hubb., inbreds (Tift 23DB and Tift 23B) were compared to ascertain the effect of the d2 gene on forage quality. In spaced plants, the d2 gene reduced rate of growth, internode length, plant height and dry matter yields without otherwise affecting the appearance of the plants. It increased leaf percentage, in vitro dry matter digestibility, and crude protein content of the stems. When grown in dense stand in two‐row plots and cut at 2‐, 4‐, 6‐, 8‐, and 10‐week intervals, dwarf millet yielded from 91 to 69% as much dry matter as tall millet. When grown in 0.9‐m rows in a well‐fertilized field, chopped at the boot stage (74 days after planting) and dehydrated, dwarf millet yielded only 78% as much dry matter as its tall counterpart. But eight dairy heifers fed to appetite ate 21% more dehydrated dwarf forage, gained 49% faster, and produced as much gain per hectare as heifers similarly fed tall forage. When grazed rotationally with the put‐and‐take system, d2 millet supplied only 85% as many steer days but gave the same total steer gains per hectare and permitted 20% better daily gains than tall millet.
Soil Nitrate, Soil Water, and Grain Yields in a Wheat‐Fallow Rotation in the Great Plains as Influenced by Straw Mulch1
Authors: Smika D. E. , Black A. L. , Greb B. W. 
Published: July 2010

AbstractWheat straw mulch rates greater than 3,360 kg/ha were needed to significantly reduce soil NO3−N during fallow at three Great Plains locations. Smaller amounts of NO3−N in the soil at the end of fallow with stubble mulch did not limit grain production. Grain yields of wheat (Triticum aestivum L.) were positively correlated with stored soil water at seeding all years at Akron, 2 out of 5 years at North Platte and 2 out of 3 years at Sidney, but there was no relation between grain yields and soil NO3−N at seeding at any of the locations. Mulched soils contained more water and less NO3−N at seeding than bare soils. In 7 out of a total of 11 crop years from all locations when grain yields were higher from mulched soil than from bare soil, soil NO3−N was available in sufficient quantity under both treatments so that final grain yields were not limited. In those years when grain yields were reduced by the presence of a straw mulch, no evidence was obtained that indicated this reduction was due to an inadequate supply of N. Grain yield responses to added N were greater on bare soil than on mulched soil.
Temperature Effects on the Fatty Acid Composition of the Seed Oil of Wild Species of Flax1
Authors: Yermanos D. M. , Patil S. H. , Hemstreet S. 
Published: July 2010

AbstractLinum angustifolium Huds. (2n=30), L. grandiflorum Desf (2n=16) and L. schiedeanum S. & C. (2n=36) were grown in growth chambers at constant 15.5 C night temperature and three day temperatures, 15.5, 21 to 26, and 32 C. Fatty acid composition of their seed oil was determined by gas liquid chromatography. At the 15.5 C treatment, L. angustifolium and L. grandiflorum had a significantly higher linolenic acid content (62.5% and 63.8%, respectively) and a lower oleic acid content (14.4% and 14.1%) than at the 32 C treatment (47.5%, 44.6%, 25.7% and 31.8%, respectively). L. angustifolium also had a significantly higher stearic acid content at the higher temperature (9.4 vs. 4.3%). By contrast in L. schiedeanum, the increase in oleic acid at 32 C (13.1% vs. 6.1% at 15.5 C) was associated with a significant decrease in linoleic acid at (73.1 vs 78.8% at 32 C) instead of a decrease in linolenic acid. Differential response to temperature effects indicates that different metabolic pathways control fatty acid synthesis in these species.
Combined Analysis of Yield Data from Fertilizer Experiments1
Authors: Laird R.J. , Cady F.B. 
Published: July 2010

AbstractThe corn (Zea mays L.) yield data obtained with four levels of nitrogen at 76 locations were combined to give a general equation with yield expressed as a function of applied N variables, productivity factors, and interaction variables. Three regression procedures — stepwise, backward elimination, and an approach based on agronomic considerations — were employed in producing a general yield equation. The pooled blocks within sites error and combined experimental error, calculated from the analyses of the individual experiments, were used for testing the significance of the site variable and plot variable regression coefficients, respectively.High correlations existing between pairs of the independent variables prevented a meaningful interpretation of the coefficients in the estimated regression models. The total variation in yield accounted for by the three regressions was similar, although the terms dropped from the full model in producing the agronomic model resulted in a significant reduction in the regression sum of squares. However, when the estimated models were used to predict yields for sites not included in the estimation procedure, the agronomic model predicted better than the other models.
Survival of Plants under Prolonged Flooded Conditions1
Authors: Yu Peter T. , Stolzy L. H. , Letey J. 
Published: July 2010

AbstractBarley (Hordeum vulgare L.), corn (Zea mays L.), sunflower (Helianthus annus L.), tomato (Lycopersicum esculentum L.), and ‘Pato’ and ‘Inia’ varieties of wheat (Triticum vulgare L.) were grown in Krilium‐stabilized Yolo loam in pot culture under greenhouse conditions until the root systems were well established. The plants were then subjected to full‐flooded, half‐flooded, and temporarily‐flooded treatments. Observations of plant growth rates under treatments were made by periodically measuring top and root length. Plants were harvested after 2 to 4 weeks of treatment and the air‐filled root porosity was measured for each root system.Reduction in growth rates and dry weights for all plants was observed in full‐flooded as compared to nonflooded treatments. Damage caused by full‐flooding was less severe in corn, sunflower and Pato wheat, and was associated with a more porous root system of these plant species as compared to the other species studied. Root porosities of these three plants were greatly increased in full‐flooded as compared to non‐flooded conditions. These results suggest that tolerance to excess moisture was related to plant internal aeration which might be achieved by increases in root porosity. Reduction in weight and growth rates was significant in full‐flooded but not signification half‐flooded conditions when compared to control.
Effects of Nonionic Surfactants on Monocots1
Authors: Endo R. M. , Letey J. , Valoras N. , Osborn J. F. 
Published: July 2010

AbstractThe effects of two commercial nonionic surfactants, Aqua Gro and Soil Penetrant, on seed germination, shoot growth, and root growth of various monocots were investigated in solution culture and soil. Plant species included in the studies are barley (Hordeum vulgare lb.), common ryegrass (Lolium multiform L.), creeping bentgrass (Agrostis palustris L.), Kentucky bluegrass (Poa pratensis L.), tall fescue (Festuca arundinacea L.), and common bermuda (Cynodon dactylon L.). Both surfactants were found to be more toxic to plants in solution as compared to soil. This result was assumed to be because of adsorption of surfactant by soil thus reducing its toxicity. Other than a few specific exceptions, Soil Penetrant was found to be more toxic than Aqua Gro—especially in the soil experiments. The mode of action of either surfactant is not known, but the cytological observations suggest that the effects may be on cellular membranes.
Effect of N, P, and K on the Percent and Yield of Oil in Corn1
Authors: Welch L. F. 
Published: July 2010

AbstractFertilizer N, P, and K increased percent oil in corn (Zea mays L.) grain relatively less than they increased grain yield. The relative increase in percent oil was 8, 3, and 2% for N, P, and K, respectively. Oil yield was increased an average of 43, 54, and 11% by the addition of N, P, and K, respectively. The increase in yield of oil per unit land area was due more to increased grain yield than to increased percent oil in the grain.
Nitrogen, Phosphorus, and Potassium Influence Yield and Chemical Composition of Bluejoint Forage1
Authors: Laughlin Winston M. 
Published: July 2010

AbstractField studies were conducted in the Matanuska Valley with bluejoint (Calamagrostis canadensis) from 1963‐7 with annual applications of three N rates with and without P and K. N application increased dry‐matter yields, N and Mg content, and N, P, and K uptake. N response increased each year when P was used. N decreased Ca, Al, B, Ba, and Sr concentrations. P application increased dry‐matter yields, stand density, P, Ca, Mg, K, and Mn contents, and N, P, K, Ca, and Mg uptake and decreased the N percentage. K application increased dry‐matter yield and K and Cu content only when P was used. K depressed Ca, Mg, Ba, B, Sr, and Zn contents.Native bluejoint responds favorably to N and K fertilization when adequate P is used.
Leaf Water Potentials of Sorghum and Corn, Estimated with the Pressure Bomb1
Authors: De Roo H. C. 
Published: July 2010

AbstractThe pressure bomb method for rapid field measurements of water stress in sorghum and corn was evaluated with the thermocouple psychrometer technique. A bomb was used to measure the sap pressures in the vascular bundles of the leaf blades. These values formed acceptable estimates of the leaf water potentials as measured with the thermocouple psychrometer. The osmotic potentials of the xylem sap, measured periodically with the psychrometer, were shown to be relatively small and therefore unimportant.