bluuebunny/crossref_metadata_2025 huggingface dataset:
Atrazine and the Nitrate Content of Corn1
Authors: Doll J. D. , Meggitt W. F.
Published: July 2010

Corn treated with atrazine and grown in controlled environment chambers and in the field was analyzed for its nitrate nitrogen (NO3‐N) content. An increase in the NO3‐N was induced by atrazine at low temperatures in controlled environment chambers. In the field corn was planted at an early (May 10) and a late (June 17) date to expose field grown plants to two temperature regimes. The only atrazine induced NO3‐N increases occurred during the early months in the corn planted on May 10. At the silage stage, no significant atrazine induced NO3‐N increase was found in either the late or early planted corn.

These studies indicate that any NO3‐N increase in corn induced by atrazine occurs only at low temperatures and that there is no accumulation of nitrate at the silage stages in corn treated with herbicidal rates of atrazine.
Influence of Fungicides, Herbicides and Combinations on Emergence and Seedling Growth of Cotton1
Authors: Kappelman A. J. , Buchanan G. A.
Published: July 2010

The effect of selected fungicides, herbicides, and fungicide‐herbicide combinations on emergence and seedling growth of cotton was studied on four soils in the greenhouse. Herbicides used as preplant, preemergence, and postemergence treatments all reduced seedling growth. Soil fungicides increased emergence and early growth of cotton plants; however, this increase was not evident in 7‐week‐old plants. Both emergence values and seedling growth were reduced by various pesticide combinations. Plants from plots treated with Lanstan and then treated preemergence with prometryne emerged faster than plants treated with other combinations. However, Lanstanfluometuron treated plants were taller at 2 weeks than plants receiving other treatment combinations. Interactions were also measured between soils and all chemicals.
Influence of Placement on Uptake of Tagged Nitrogen by Rice1
Authors: Broadbent F. E. , Mikkelsen D. S.
Published: July 2010

The placement of two N‐15 tagged fertilizer sources applied to lowland rice was studied to determine the effects on yield components, fertilizer N uptake and the residual N present after cropping. Tiller number and bearing tillers were increased by fertilization, but the source and placement had no effect. Grain yield was increased by N fertilization with ammonium sulfate and urea but was not affected by source. Broadcast applications gave lower yields than other treatments while the highest yields were obtained with half the N placed in the soil and the balance top‐dressed. Fertilizer N in the Y‐leaf and total plant uptake showed the superiority of banding with variations in total N uptake varying from 26 to 47%. Ammonium sulfate provided a larger increment of N to grain production than urea and also showed a lower magnitude of N loss from the soil‐plant system.
Critical Plant Nutrient Composition Values Useful in Interpreting Plant Analysis Data1
Authors: Melsted S. W. , Motto H. L. , Peck T. R.
Published: July 2010

Plant analyses can be a powerful tool in the diagnosis of yield depressions. Critical plant composition data for corn, soybeans, wheat, and alfalfa are presented which can be useful in interpreting plant analyses. Data are also presented to indicate “normal” variations that may be expected to occur in plant composition resulting from variations in varieties, seasons and soil. For the corn plant, the nutrient composition of some elements change with the leaf sampled and the maturity of the plant.
Relationship of Corn Silage Yields to Maturity1
Authors: Rutger J. N.
Published: July 2010

Ten years of corn silage yield trials were used to calculate regressions of fresh silage and silage dry matter yields on maturity. Fresh silage yields of late hybrids were considerably higher than those of early hybrids. However, dry matter yields of the early hybrids were nearly as high as those of the late entries. Thus harvest and storage costs per unit of dry matter production would be higher for the late hybrids. Greater dry matter storage losses also would be expected from silage made from the late hybrids. Finally, silage made from early hybrids has a higher feeding value, primarily because an animal can consume more pounds of dry matter per day of dry silage than of wet. For these reasons, in areas where early maturity is a major consideration it is suggested that hybrids used for silage should be fully as early as the best adapted grain hybrids for that region.
Seed Drying and Viability in Dallisgrass1
Authors: Bennett Hugh W. , Marchbanks W. W.
Published: July 2010

Dallisgrass seed was harvested 14, 21, and 28 days after the peak of flowering. They were then dried for 8, 16, 24, 36, and 72 hours, at temperatures of 38, 43, 49, 54, and 60 C (100, 110, 120, 130, and 140 F). These seed and their enclosing glumes contained over 35% moisture which dropped rapidly thereafter. A very rapid loss of moisture occurred at each of the five temperatures used for the first 8‐hour drying period.

The viability of mature seed from all harvests was good when dried at all temperatures. Lower germination of seed harvested 14 days after flowering was due to the presence of immature embryos.

Seed dried at 60 C germinated equal to or better than seed of the same maturity dried at 38 C. This suggests that drying at high temperatures may stimulate the germination of dallisgrass seed.

Revisions in time and method of harvesting dallisgrass seed are suggested from the results of seed drying as well as the rate of importance of seed shattering.
Evaluation of Techniques for Measuring Drought Avoidance in Cereal Seedlings1
Authors: Salim M. H. , Todd Glenn W. , Stutte C. A.
Published: July 2010

Water 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

Daily 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

Late 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

Bray 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

We 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

A 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.
Effects of Soil Moisture Stress on Seed Germination1
Authors: Hadas A.
Published: July 2010

Effects of soil moisture stress were reviewed and calculations were carried out to assess the effects of seed coat permeability, contact area, and water supply on water imbibition in germinating seeds. The calculated values were compared and discussed in the light of experimental data available.
Relationship of Soil Texture to Sulfur Oxidation1
Authors: Rehm G. W. , Caldwell A. C.
Published: July 2010

The 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

Loblolly 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

Four 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

Pot 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

The 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

Corn (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

A 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

Near‐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

Wheat 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

Linum 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.
An Inexpensive Soil Crusher‐Siever1
Authors: Turne B. C. , Isensee A. R.
Published: July 2010

The design and assembly of an inexpensive soil crusher‐siever is described. This machine provides fast operation and a considerable versatility in the quantity of soil that may be prepared; and its design eliminates costly custom construction.
Combined Analysis of Yield Data from Fertilizer Experiments1
Authors: Laird R.J. , Cady F.B.
Published: July 2010

The 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

Barley (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

The 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

Fertilizer 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

Field 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

The 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.
Influence of Soil Salinity on Production of Dry Matter and Uptake and Distribution of Nutrients in Barley and Corn: I. Barley (Hordeum vulgare L.)1
Authors: Hassan Nouri A. K. , Drew James V. , Knudsen Delno , Olson Robert A.
Published: July 2010

The production of dry matter and the uptake and concentration of nutrients by barley (Hordeum vulgare L.) from soil adjusted to different levels of salinity with a mixture of salts were evaluated in a greenhouse study. Following germination of the plants, soil salinity levels ranging from EC values of 0 to 30 mmhos/cm of the soil solution at field capacity were induced by additions of a salt solution containing one part Na2SO4, one part MgSO4, and one part CaCl2. During the growth period of 98 days, increasing soil salinity increased sulfate‐S and chloride in the saturation extract and lowered soil pH. Exchangeable Na, Mg, and Ca increased markedly while exchangeable K and available P increased only slightly. Acid‐extractable Mn increased, but there was little or no effect on acid‐extractable Zn, Fe, and Cu. Production of dry matter by the vegetative parts and grain heads of barley increased up to an EC of 12, then decreased at salinity levels above this value. Coefficients of correlation indicate significant negative relationships between soil salinity and uptake of P, K, Ca, Fe, and Cu by the vegetative parts and grain heads of barley. Conversely, significant positive correlations occur between soil salinity and uptake of Mn and Na by barley.
Associations Among Disease Resistance, Agronomic Characteristics, and Chemical Constituents in Flue‐Cured Tobacco1
Authors: Chaplin James F.
Published: July 2010

Four hundred and sixty‐six F5 breeding lines of fluecured tobacco were evaluated for associations among disease resistance, agronomic characteristics, and chemical constituents. These lines were derived from a cross between ‘NC 95’ and ‘MR Coker 139.’ Resistance to the following diseases were evaluated: tobacco mosaic virus (TMV), root‐knot, black shank, bacterial and fusarium wilt. Considerable yield decreases were associated with mosaic and fusarium wilt resistance. Yield decreases were greater when resistance to these two diseases was combined in the same line. Value per 45.4 kg was reduced slightly in all disease resistant lines when compared with susceptible ones. Further reductions in value per 45.4 kg were associated with lines resistant to more than one disease. Slight associations between resistance to some of the diseases and other characteristics such as percent sugars, total alkaloids, plant height, length and width of leaves were also noted. Narrow leaf type plants were associated with reduced yield and value per 45.4 kg. Black shank resistance was also associated with plant type, the narrow leaf types being slightly more resistant. Yield was highly correlated with value per hectare, value per 45.4 kg, width of leaves, days to flower, and percent sugars. Value per hectare was also correlated with value per 45.4 kg, width of leaves, height of plant, days to flower, and sugars. In addition, value per 45.4 kg was positively correlated with percent sugars.
Amount and Distribution of Hydrocyanic Acid Potential during the Life Cycle of Plants of Three Sorghum Cultivars1
Authors: Loyd Robert C. , Gray Elmer
Published: July 2010

Plant parts of ‘Piper’ and ‘Greenleaf’ sudangrass (Sorghum bicolor var. sudanese (L.) Moench.), and ‘Suhi‐1’, a sorghum (Sorghum bicolor (L.) Moench.) ✕ sudangrass hybrid, were assayed for hydrocyanic acid potential (HCN‐p) at intervals during their life cycle.

Concentrations (ppm) of HCN‐p in aboveground plant parts were generally highest in Suhi‐1, intermediate in Greenleaf, and lowest in Piper. The cultivars did not differ significantly for HCN‐p in roots. The highest concentrations of HCN‐p for each cultivar occurred in the leaves 1 week after emergence. Dry mature seed contained little or no HCN‐p. Relative rankings of leaves, stems, and roots for HCN‐p varied during the life cycle for each cultivar. Concentrations of HCN‐p of tillers, leaves, stems, heads, and roots generally decreased as maturity advanced. Correlation coefficients for concentrations of HCN‐p and total dry weight per plant were negative and significant for each cultivar.

Total HCN‐p (µg/plant) during the life cycles was greatest in Suhi‐1, intermediate in Greenleaf, and lowest for Piper. Correlation coefficients for total HCN‐p and dry weight per plant were positive but not significant for any cultivar.
Herbicides for Control of Ragweeds in Korean Lespedeza1
Authors: Peters E. J. , Lowance S. A.
Published: July 2010

We evaluated (2,4‐dichlorophenoxy)acetic acid (2,4‐D); 4‐(2,4‐dichlorophenoxy)butyric acid (2,4‐DB); 3,5‐dibromo 4‐hydroxybenzonitrile (bromoxynil); and 3,5‐dichloro‐4‐hydroxybenzonitrile (chloroxynil) for control of common ragweed (Ambrosia artemisiifolia L.) and lanceleaf ragweed (Ambrosia bidentata Michx.). Effects of the herbicides on yields of lespedeza (Lespedeza stipulacea Maxim.) forage, and yields and germination of lespedeza seed were also evaluated. The ester of 2,4‐D controlled ragweed, but seriously injured lespedeza. The ester of 2,4‐DB was not as effective as 2,4‐D on ragweed, but resultant yields of lespedeza were greater. Injury to lespedeza from .56 kg/ha 2,4‐D amine, when applied early, was offset by increased yields resulting from excellent weed control. Bromoxynil and chloroxynil at .56 kg/ha controlled ragweeds effectively and injured lespedeza less than 2,4‐D) and 2,4‐DB.
Influence of Dimethyl Sulfoxide (DMSO) on Nutrient Uptake by Potatoes and Bush Beans1
Authors: Estes G. O. , Mack H. J. , Willis D. L.
Published: July 2010

Greenhouse investigations were conducted on the effects of dimethyl sulfoxide (DMSO), as an additive to the growth media, on the uptake of P, Zn, and Mn by potatoes, Solanum tuberosum L., and bush beans, Phaseolus vulgaris L. In initial work, severe phytotoxicity occurred with beans when DMSO was applied in excess of 0.1% (wt/wt) to a mixture of Chehalis soil and sand. Severe marginal burning and desiccation of foliage of both crops occurred at higher DMSO concentrations. No visible toxicity or significant yield reductions occurred when DMSO was applied to soil at concentrations less than 0.01%.

DMSO significantly increased the uptake of Mn and decreased P uptake by beans when applied to soil at concentrations in excess of 0.01%. Hydroponic experiments with 54Mn in combination with DMSO indicated that the influence on Mn and P uptake is likely mediated through a change of pH of the growth medium rather than permeability changes of the root membrane.
Na and K Interactions in Increasing the Salt Tolerance of Atriplex halimus L.: I. Yield Characteristics and Osmotic Potential
Authors: Mozafar Ahmad , Goodin J. R. , Oertli J. J.
Published: July 2010

Growth of Atriplex halimus on four different saline media was studied. Growth was strongly stimulated by low levels of all saline media and reached a maximum at different external osmotic potentials for different salinity treatments. Plants grew much better on saline media containing equal parts of NaCl and KCl, and seemed to tolerate much lower external water potential than plants growing on NaCl, KCl, or on different concentrations of Hoagland solutions. In all the four different salinity treatments, osmotic potential of the expressed leaf sap remained nearly constant over all the external osmotic potentials. Although salinity did not change final size of the leaves, the fresh weight and dry weight of a given area of the leaves changed tremendously, depending upon the osmotic substrate. The effect of the kind of osmotically active salt present in the saline medium on the growth of A. halimus indicates that growth reduction under saline media is not solely a function of its osmotic potential. It appears that overall growth effects can best be described as a combination of stimulatory and inhibitory effects.
Effect of Growth, Senescence, and Curing on Fatty Acid Composition of Tobacco
Authors: Tso T. C. , Chu Hilda
Published: July 2010

Leaf samples were obtained from two varieties of tobacco (Nicotiana tabacum L.) at various stages of growth, senescence, and under two methods of flue curing. Under the experimental condition, fatty acids detected included 12:0, 14:0, 15:1, 16:0, 16:1, 18:0, 18:1, 18:2, and 18:3. The combined fatty acids reached a peak amout 4 weeks after transplanting while crude lipid continued to increase with the physiological age of the leaf. Higher fatty acids, especially unsaturated ones, decreased beginning at early senescence; the most extensive decrease occurred at the yellowing stage of leaf curing. The decrease was approximately in proportion to the degree of fatty acid unsaturation. During the same period, there was a slight increase of comparatively shorter and more saturated fatty acids. However, no interconversion between long chain unsaturated fatty acids and short chain saturated acids was detected by air‐curing experiments with C14‐U‐linolenic acid supplied to detached leaves.
Wind Structure above and within a Soybean Canopy1
Authors: Perrier E. R. , Millington R. J. , Peters D. B. , Luxmoore R. J.
Published: July 2010

The turbulent structure of wind within and above a soybean canopy was studied utilizing observations of wind speed, standard deviation, and frequency distributions. Within the validity of the one‐dimensional logarithmic profile relation .(above the soybean canopy) the transfer coefficient and mixing length are calculated. The data indicate that the fluid motion within the soybean canopy is aerodynamically different from the turbulent air layer above the plant canopy, which suggests a two‐dimensional flow cavity. The skewed frequency distribution and high standard deviations within the soybean canopy suggest difficulty in describing the vector direction and gradient relations using data collected from anemometers which measure all wind components in the horizontal plane.
Tannin Content and Digestibility of Sorghum Grain as Influenced by Bagging1
Authors: Harris H. B. , Cummins D. G. , Burns R. E.
Published: July 2010

The relationship was studied between tannin content and in vitro dry matter digestibility (DMD) of sorghum [Sorghum bicolor (L.) Moench] grain of various colors grown in the Georgia uniform grain sorghum variety trials at Experiment and Blairsville, Ga., in 1968. Bagging panicles before or immediately following anthesis significantly (P < .05) reduced the tannin content brown‐seeded hybrids permitting the evaluation of the effect of tannin content at two levels in the same genetic background and growing conditions on DMD percentages. Regardless of whether panicles were bagged or not, highly significant (P < .01) negative correlation coefficients were obtained between tannin and DMD percentages. This finding substantiates the hypothesis that high levels of tannin in sorghumg rain reduces the feeding efficiency. Genetic reduction of the brown color and tannin content of the grain, as in the case of one tan‐seeded hybrid, demonstrates that the feeding quality of bird and weather resistant varieties may be improved through breeding.
Influence of Row Spacing, Irrigation, and Weeds on Dryland Flax Yield, Quality, and Water Use1
Authors: Alessi J. , Power J. F.
Published: July 2010

Field experiments were conducted during 1966 and 1967 at Mandan, N. D. to evaluate the effects of row spacing (7.5, 15, and 30 cm), irrigation water at fruiting, and weed competition (primarily from Setaria virilis) on water use by flax (Linum usitatissinum L.). An irrigation of 50 mm at the fruiting stage increased flaxseed yields only when weeds were controlled, particularly in the dry year of 1967. Flaxseed yields increased at row spacing narrowed from 30 to 7.5 cm only on unweeded plots. Weed growth reduced flaxseed yields for the 2‐year period from 26 to 53%, with the least reduction from 7.5‐cm row spacing. Midsummer rains or supplemental water at fruiting was less effective in increasing flaxseed production when weeds were present, but some degree of weed control was achieved with narrower row spacing. Oil content of flaxseed was not affected by treatments, but iodine number was slightly higher for the wider spacing (30 cm) in 1966. Total water use was not affected by row spacing or weed treatment, but water use efficiency was increased by narrow row spacing and by weed control. Water use patterns indicated deeper root penetration during the drier year.
Semidwarf Winter Wheat Response to Early Spring Clipping and Grazing1
Authors: Pumphrey F. V.
Published: July 2010

Vegetation removal in early spring by clipping or by grazing was studied in six fields of semidwarf winter wheat (Triticum aestivum L.). Varieties grown were ‘Games’ or ‘Nugaines’ which are common soft white wheat having exceptional stooling and yielding ability. Grazing was started as soon as livestock could obtain adequate feed from the early spring growth and stopped prior to the time the upper node could be removed by grazing. Clipping treatments were applied during this period.

Removing vegetation either by clipping or by grazing significantly decreased grain yields. Plant height, heads per square meter, and straw production were reduced by vegetation removal. Increasing the amount of vegetation removed, extending the length of time vegetation was removed, or delaying the starting of clipping or grazing increased the reduction in each of these characters.

Clipping simulated grazing of the early spring growth within the limits of humans to estimate when and how much forage to remove to duplicate grazing.
Water Deficit Effects on Corn. I. Vegetative Components1
Authors: Claassen M. M. , Shaw R. H.
Published: July 2010

Corn was grown in large buried containers and stressed nonrepetitively by cessation of irrigation at nine different times during the season. Each stress treatment consisted of 4 days on which the uppermost, fully‐expanded leaves were wilted. Water status of the yield plants was estimated in terms of the relative turgidity (RT) of like‐treated plants, soil moisture and other environmental factors. Vegetative component yields were determined in two experiments, the first including the additional factor of limiting soil fertility. Each component was significantly influenced by one or more of the stress periods. Maximum reductions in total vegetative dry matter production of 15 to 17% resulted from water deficits approximately 3 weeks before 75% silking. Significant increases in stalk weight occurred as a result of stress at late silking and very early ear stages.
Wheat Seed Protein: Chemical Influence on and Relationship to Subsequent Growth and Yield in Michigan and Mexico1
Authors: Ries S. K. , Moreno O. , Meggitt W. F. , Schweizer C. J. , Ashkar S. A.
Published: July 2010

Simazine [2‐chloro‐4,6‐bis (ethylamino)‐s‐triazine] and terbacil [3‐tert‐butyl‐5‐chloro‐6‐methyluracil] were applied at subherbicidal rates as protein and growth regulators to wheat at two Michigan locations in 1968 and 1969 and at Ciudad Obregon, Mexico in 1969. Different N levels were used at all locations. Winter wheat from Michigan and spring wheat from Mexico were planted at two Michigan locations to determine the effect of herbicide and N treatments on the growth, yield, and protein content of the second generation.

Neither supplemental N nor herbicides increased the yield and protein content in all experiments. Nitrogen increased both the yield and protein content in three out of the four tests. Subherbicidal applications increased the protein content in all tests and also the yield in two tests.

Increases in seed protein due to both herbicide and N applications were reflected in higher yields the next generation in all three Michigan field experiments. Yield was directly correlated with seed protein content, but not with seed size. In one test in Mexico the effect of protein in the seed on the next generation was eliminated by 120 kg N/ha applied at time of planting.
Measurement of Soil‐grown Roots in a Rhizotron1
Authors: Taylor H. M. , Huck M. G. , Klepper Betty , Lund Z. F.
Published: July 2010

Measurements were made of both shoot and root growth on a corn (Zea mays L.) and a tomato (Lycopersicon esculentum Mill.) plant in a rhizotron. Root intensity at the transparent panel was estimated by two methods. It increased during the growing season for both species, but was always greater for corn. Estimates of root density and total root length were three times greater for corn than for tomato at the end of the growing season. Side walls and glass panels showed no concentrating effect on root growth.
2‐Chloro‐6‐(Trichloromethyl) Pyridine as a Nitrification Inhibitor for Anhydrous Ammonia Applied in Different Seasons1
Authors: Hughes T. D. , Welch L. F.
Published: July 2010

Field experiments were conducted to study the effects of 2‐chloro‐6‐(trichloromethyl) pyridine, N‐Serve, on nitrification of anhydrous NH3. Applications of 0, 0.56, and 1.12 kg N‐Serve/ha in all possible combinations with 0, 112, and 224 kg N/ha were made on March 30, June 4, and November 25, 1968. Concentrations of NH4+‐N in the NH3 retention zones were determined at various times following application.

N‐Serve decreased the rate of nitrification. Nitrification inhibition was evident at the first sampling (14 to 41 days from NH3 application) and persisted until almost all NH4+ had nitrified. N‐Serve was inhibitory at all locations within the NH3 retention zone. As an average of all application dates and N rates, there was 52% as much NH4+ present at the first sampling with no N‐Serve as with 1.12 kg/ha of N‐Serve. There was 82% as much NH4+ present at the first sampling with 0.56 kg/ha N‐Serve as with 1.12 kg/ha N‐Serve.