bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Moisture, Plant Population, and Nitrogen on Dryland Corn in the Northern Plains1
Authors: Alessi J. , Power J. F.
Published: July 2010

Synopsis

The effects of total available soil moisture, plant population, and N fertilization upon dryland corn production were studied at 2 locations, over a 6‐year period. Forage and grain yields were highly correlated with total available moisture (soil moisture at planting plus precipitation). Optimum population at each location was 10,000 plants per acre. Applications of N were of little benefit.
Fatty Acid Composition of Seed Oil of Wild Species of Linum1
Authors: Yermanos D. M. , Beard B. H. , Gill K. S. , Anderson M. P.
Published: July 2010

Fatty acid composition of seed oil of 34 wild species of flax was determined. The same fatty acids were present in these species as in cultivated flax. Variability in their relative proportions, however, was greater among wild species than among 266 lines of cultivated flax analyzed. In general wild species had a high linolenic acid content. A few species, however, had high linoleic and low linolenic acid content.
Responses of Some Semi‐Dwarf Spring Wheats to Nitrogen and Phosphorus Fertilizer1
Authors: Woodward R. W.
Published: July 2010

A breeding program that utilized semi‐dwarfs of Norin 10 origin, was commenced at Logan, Utah, in 1953. The ultimate aim was the production of a short, high‐yielding, disease‐resistant, good milling, hard red spring wheat.

Yields of three varieties of hard red spring, semidwarf wheat increased proportionately more than those of three tall, hard red springwheats as a result of applying nitrogen early in the growing season. During a 4‐year study, yield, height, lodging, percent protein, and sedmimentation values were all increased, except in very fertile soil, by the addition of nitrogen. Yield increases were primarily due to the production of more tillers. No increases were evident in the number of kernels per spikelet, per head, or in kernel weight. Added phosphorus gave no significant increase in any measured character. Net dollar returns from semi‐dwarfs were nearly double those from tall, hard red spring wheats when both were fertilized with nitrogen.
Assessing Feed Quality of Fertilized Coastal Bermudagrass (Cynodon dactylon (L.) Pers.) with Rabbits1
Authors: Adegbola Anthony A. , McKell Cyrus M. , Casady Robert B.
Published: July 2010

The forage quality of Coastal bermudagrass hays from plots fertilized at 0, 100, and 250 pounds N per acre was evaluated using 8‐week‐old rabbits as test animals. The grass hays replaced the 40% alfalfa hay normally incorporated into the control diet.

The rabbits fed on fertilized bermudagrass diets were apparently adversely affected by the level of nitrate nitrogen and vitamin A in some of the diets. The results suggest that rabbits may be quite sensitive to high nitrate level and their use in evaluating the supply of metabolisable energy in forage crops or for obtaining data on feed conversion should be carefully examined as such data might lead to wrong interpretation.
Influence of Row Spacing and Nitrogen Levels on Dry Matter Yields of Kenaf (Hibiscus cannabinus L.)
Authors: Williams J. H.
Published: July 2010

Kenaf is a potential annual paper pulp crop. Dry matter yields which are sufficiently high to compete with existing crops in Nebraska are needed. Adaptation and cultural studies were undertaken to determine the levels of productivity that can be expected in Nebraska. Irrigated and nonirrigated studies with different varieties, row spacings, and nitrogen fertilization were studied.

Average dry matter yields of kenaf of 3.70 and 6.89 tons per acre were obtained in 5 years of nonirrigated and 2 years of irrigated tests, respectively. In only 2 of the 5 years were kenaf yields sufficiently high under nonirrigation to compete economically with corn or wheat grown under comparable conditions. Average kenaf yields were almost doubled under irrigation but were not considered high enough to compete with corn grown under similar conditions.

Kenaf planted at a rate of 15 pounds per acre in rows spaced 14 inches apart gave highest yields in irrigated tests. The data indicate that higher populations (narrower rows or heavier rate within rows) might have yielded more dry matter per acre. Under nonirrigated conditions, yields from 21‐inch rows were highest but were not significantly different from other row spacings tested.

Nitrogen applications, up to 150 pounds per acre under irrigation and 100 pounds per acre under nonirrigated conditions, did not significantly increase dry matter yields of kenaf.

Kenaf samples harvested from 7‐inch and 28‐inch row spacings (2.0 and 0.8 plants per square foot) received similar compositional ratings for pulping potential.
Response of Grain Sorghum to Seedbed Compaction1
Authors: Dasberg S. , Hillel D. , Arnon I.
Published: July 2010

Various degrees of compaction were carried out prior to and immediately after planting a summer crop of sorghum under conditions of dryland farming. Soil physical properties—bulk density, penetrability, air permeability and surface cracking—were affected appreciably only to a depth of 15 cm. Preplanting compaction significantly reduced seedling emergence and yields. Postplanting treatments increased sorghum stand density and yield significantly.
Relation of Lime and Preemergence Herbicides to Yields of Cotton and Weeds1
Authors: Savage K. E. , Bardsley C. E.
Published: July 2010

The growth of cotton and weeds on Wickham sandy loam was used to evaluate the effectiveness of pre‐emergence herbicides on limed and unlimed soil. Diuron, cotoran, prometryne, and trifluralin were more effective in controlling weeds in limed soil than in unlimed soil, primarily because of weed growth. Although there were no significant differences in weed yields among the different herbicides, as a group they were more consistent in behavior on unlimed soil than on limed soil. The herbicides were responsible for a highly significant increase in the yields of seed cotton over yields obtained with no herbicides. Competition between weeds and cotton for moisture and fertility was largely ruled out in this difference. However, delayed maturity of the cotton indicated that weeds probably affected the air, light, and humidity in the crop. The correlation coefficients for yields of cotton with yields of weeds were −0.91** for unlimed soils and −0.67 for limed soils.
Comparison of Nitrogen Fertilized Grasses with a Grass‐Legume Mixture as Pasture for Dairy Cows I. Dry Matter Production, Carrying Capacity, and Milk Production1
Authors: Clark N. A. , Leslie J. I. , Hemken R. W.
Published: July 2010

A study was conducted in 1960, 1961, and 1962 to compare orchardgrass grown under three rates of nitrogen, 100, 200, and 300 pounds per acre; orchardgrass‐ladino clover; and Midland bermudagrass with sod seeded cereal rye, as pasture for lactating dairy cows. The bermudagrass became overmature and unpalatable in 1960, but in 1961 and 1962 the quality was improved through higher nitrogen fertilization, and more severe clipping and grazing practices. Nitrogen applications up to 200 pounds per acre resulted in increased dry matter production over the grass‐clover mixture. Clover in the mixture declined each year. Crude protein and nitrate nitrogen increased with increasing rates of nitrogen fertilization. Management of the bermudagrass greatly affected its protein content. The nitrate levels obtained were not considered to be toxic. Animal carrying capacity followed the pattern of dry matter production. Average per cow milk production was highest on grass‐clover pastures, and the response of cows on the other pastures was quite variable. Milk production dropped drastically on poorly managed bermudagrass, but in 1961 and 1962 production was comparable to that of cows on orchardgrass. The potential yield of milk per acre was higher on pastures where higher stocking rates were possible.
Factors Affecting Measurements of Oxygen Diffusion Rate (ODR) with Bare Platinum Microelectrodes1
Authors: Kristensen K. J.
Published: July 2010

The electrical resistance in the soil between the platinum electrode and the reference cell is very high in normal soils. Depending on the salt and water content, values from 5,000 to 20,000 ohms are commonly found. Drainage of the soil tends to increase the resistance, while the potential oxygen diffusion increases. However, the actual oxygen reduction will partly depend on the electrical resistance according to Ohm's law. This is discussed in the present paper and a method is suggested by which the current flow (ODR) can be corrected.
Comparisons of F1 and F2 Grain Sorghums for Yield and Other Agronomic Characteristics1
Authors: Nasr H. G. , Worzella W. W.
Published: July 2010

A 2‐year study was conducted under irrigation in Lebanon comparing F1 and F2 grain sorghums.

Average grain yields of F2 hybrids were 13.5 and 20.8% less than those of F1 hybrids for the 2 years. Stover yields and test weights, however, were not influenced by planting either F1 or F2 generation seed. Average date of flowering of the F2 sorghum plants was delayed a few days, and the F2 heads were a few grams lighter than F1 heads. In some hybrids the F1 plants were taller and their heads were longer than the F2 plants and heads. However, kernel weights from F2 sorghum plants were heavier than from F1 plants.

Less variation was observed between plants in each F1 population than between plants of the corresponding F2 population for the following characteristics of six sorghum hybrids: days to flowering, plant height, head length, head weight, and 100‐kernel weight. The study revealed that F2 grain sorghum hybrids were inferior in yield to F1 hybrids. In addition, the F2 produced plants that varied widely in maturity, height and other agronomic characteristics, which made sorghum harvesting and processing more difficult.
Testing for Drought and Heat Resistance in Kentucky Bluegrass
Authors: Gaskin T. A.
Published: July 2010

Strains of Kentucky bluegrass (Poa pratensis L) were tested for growth and survival under conditions of high temperature with adequate moisture and under conditions of soil drougth. Several clones (A–31, A–17, and A–21) had both heat and drought resistance, while others (A–34, A–1o, A–18, A–19, and A–36) were superior only in growth under high temperature.
Comparison of Methods for Evaluating the Response of Lawngrass to Irrigation and Nitrogen Treatments1
Authors: Mantell A. , Stanhill G.
Published: July 2010

The growth of a Kikuyu grass lawn on sandy loam soil was studied in a factorial experiment which included five irrigation frequencies (7, 14, 21, 25, and 30 days) and three levels of nitrogen fertilization (0, 2.1, and 4.2 kg N/1000 m2/month). Four methods were used in evaluating lawn quality: visual rating, leaf chlorophyll content, light reflection, and plant density. All methods were highly sensitive in detecting changes in the condition of the grass. An increase in either irrigation frequency or nitrogen application improved lawn quality (higher visual rating, lower light reflection, greater chlorophyll content, and higher plant density). The light meter readings indicated regular cycles of color change during the irrigation season. Correlations between all the methods were highly significant. It is suggested that by selecting a desirable lawn rating and determining the equivalent level of reflected light, management practice could be regulated with the use of a photocell. The method is characterized by its simplicity, rapidity, and objectivity.
Effects of Air Movement and Syringing on the Microclimate of Bentgrass Turf1
Authors: Duff D. Thomas , Beard James B.
Published: July 2010

Air movement of 4 mph reduced turf mat temperature a maximum of 13 F compared to that reached when air movement was restricted. A maximum difference of 10 F was observed at a two inch soil depth under the two air movement regimes. Relative humidity 3 inches above the grass was not influenced by air movement at 4 mph.

Temperature reduction resulting from syringing with 0.25 inch of water at 12 noon was small in both the mat and at the 2‐inch soil depth. However, syringing prevented temperature from reaching the maximum which would have occurred had no water been applied.
Prostrate vs. Common Dallisgrass Under Different Clipping Frequencies and Fertility Levels1
Authors: Hart Richard H. , Burton Glenn W.
Published: July 2010

Prostrate and common dallisgrasses were fertilized with 0, 50, 100, 200, or 400 pounds of nitrogen per acre, and harvested every 2 or 4 weeks. Prostrate consistently produced higher forage yields than common, with the difference between varieties more marked at higher nitrogen levels and when cut every 4 weeks. Yields of both grasses were higher when cut every 4 weeks than when cut every 2 weeks, and increased with increasing rates of nitrogen, up to 400 pounds per acre. Higher yields of prostrate were due to faster growth in June, July, and August, with little difference between varieties before or after this period. Crude protein content of both grasses increased with increasing nitrogen and more frequent cutting, with no significant difference between grasses. Forty months after establishment, there were fewer weeds in prostrate dallis than in common. In view of these results, prostrate dallisgrass is recommended for light, poorly drained soils in the South when seed becomes commercially available.
Physical Soil Amendments, Soil Compaction, Irrigation, and Wetting Agents in Turfgrass Management III. Effects on Oxygen Diffusion Rate and Root Growth1
Authors: Letey L. , Morgan W. C. , Richards S. J. , Valoras N.
Published: July 2010

The O.D.R. values under tensiometer guided irrigation were found to be high at the time measurements were made. Under the set irrigation program, the O.D.R. were lowest for unamended soil, next lowest for peat amended soil, and highest for soil amended with lignified redwood and calcined clay. Root growth in containers receiving water on a set schedule was associated with the measured O.D.R. A value of about 0.15 µg cm−2min−1 appeared to be the lower limit for root growth. Each amendment promoted the development of a root system of unique characteristics.
Evaluation of Methods for Estimating Numbers of Rhizobia on Alfalfa Seed1
Authors: Ham G. E. , Frederick L. R.
Published: July 2010

Comparative studies were made to determine the relative efficiency of different laboratory tests in detecting Rhizobium meliloti when alfalfa seeds were inoculated with known numbers of bacteria. The bottomless bottle (modified Leonard) and crock techniques, which utilize more than one seed per container, overestimated the number of rhizobia present on alfalfa seeds due to the transfer of rhizobia among seedlings in the test container. The transfer effect probably was due to root growth accompanied by multiplication and movement of rhizobia. Positive results (nodulated plants) in a container indicated that at least one seed carried one rhizobium. When rhizobia were present on the seed, a container with one inoculated seed gave results that were not significantly different from the results obtained when all seeds were inoculated. The agar tube technique tended to underestimate the number of rhizobia present on alfalfa seeds because the anaerobic conditions in the support medium inhibited nodule formation. The sand tube technique gave the most accurate information.
Protein Content of Wheat Kernels from Different Parts of the Spike1
Authors: McNeal F. H. , Davis D. J.
Published: July 2010

Three varieties of spring wheat were grown in replicated trials at six Montana locations. Grain protein percentages from different spikes and different parts of the same spikes were compared. Differences were not observed between main and tiller spike averages or between central and lateral kernels. However, a significant protein X location interaction for main and tiller heads indicates they are not always equal in protein content. Kernels from the top third of the spike were significantly lower in protein than those from the bottom and middle portions.
Influence of Moisture and Fertilizer on Growth and N and P Uptake by Sweet Peppers1
Authors: Thomas James R. , Heilman Marvin D.
Published: July 2010

abstract

Two soil moisture treatments were combined factorially with four N and three P levels in a greenhouse study. Dry matter production and N assimilation by sweet peppers were significantly affected by the application of N and P and by soil moisture level. Growth ratios under dry and wet soil conditions suggest that high soil moisture reduced N absorption or N availability at low levels of N. The inhibiting effect of high soil moisture on N uptake was overcome by application of high rates of N. Application of P fertilizer increased N uptake. Moisture and N application rate affected the recovery of fertilizer N. Under high soil moisture conditions, fertilizer N recovery increased with rate of application. The opposite effect was noted under the dry moisture regime. Total P uptake increased with the application of N fertilizer on both P‐fertilized and nonfertilized soils. Total P uptake decreased as available moisture decreased. The critical NO3‐N content of leaf tissue was approximately 500 ppm.
Effect of Placement Depth and Root‐Inhibiting Chemicals on Uptake of Strontium‐85 by Field Crops1
Authors: Menzel R. G. , Eck H. V. , Champion D. F.
Published: July 2010

abstract

Uptake of strontium‐85 was sharply reduced by burying it deeply enough in the soil or by burying it in contact with chemicals that inhibited root development in the contaminated zone. With soybeans grown at Beltsville, Md., uptake of strontium‐85 from 75 cm below the soil surface was only 1% of that from the surface 15 cm. But with sorghum grown at Bushland, Texas, uptake from 100 cm was 40% of that from the surface 15 cm. Application of sodium carbonate with strontium‐85 at 50 cm reduced uptake by both crops to only a few percent of that from the same depth when no chemical was used.
Oat Forage Production in the Cool Tropics as Represented by Colombia1
Authors: Crowder L. V. , Lotero Jaime , Fransen James , Krull C. F.
Published: July 2010

abstract

In the cool tropics, forage yields of imported oat varieties and selections ranged from 5.5 to 9.5 T/A of dry material when harvests were made at the milk stage of growth. Production declined with two cuts, one made at the vegetative stage and one at the milk stage. Yields were considerably reduced when several harvests were made at the vegetative stage.

Crude protein content of forage cut when the plants were 12 to 15 inches high varied between 15 and 20% on a dry weight basis. The more mature forage (milk stage) had from 6 to 10% protein.

On land previously uncultivated, oats responded to application of P and, to a lesser extent, N. After several fertilized cash crops, a response to N was observed in the early stage of growth of the oats and at the harvests taken in the vegetative stage. As the plants became more mature and were harvested in the milk stage, less benefit was noted from applied N and little or no response occurred with P. Oats planted after potato harvest gave high yields without the use of additional fertilizer.

Interseeded grasses and legumes became well established when oats were harvested several times in the vegetative stage of growth. When oats reached the milk stage, plant competition for soil water, light, soil nutrients and space often caused poor stands of the intersown crop, especially under water stress.

Excellent oat silage was made from plants harvested in the milk stage and stored in a tower silo. Feeding trials showed that oat silage alone gave daily beef gains of 1.6 pounds per day.
An Inexpensive Raingauge1
Authors: Gamble E. E. , Daniels R. B.
Published: July 2010

Small, inexpensive raingauges were made from 2.5‐cm electrical conduit supported in short lengths of sunken pipe. They gave readings about 5% below those of standard gauges (20‐cm diam.) but were much less susceptible to damage and vandalism.
Effect of Leaf Removal on Amylose Content of Corn Endosperm1
Authors: Helm J. L. , Fergason V. L. , Thomas J. P. , Zuber M. S.
Published: July 2010

Inheritance studies involving amylose synthesis in corn require precise estimates of the genetic potential of the genotype. Information on the effect of nongenetic factors on the amylose‐amylopectin ratio are necessary. Corn plants are often subject to loss of photosynthetic area by such factors as hail, insect damage, leaf blights, and mechanical damage. Previous workers have shown that defoliation treatments at pollinating time did not influence grain quality, but affected grain yield by a reduction in the number of developed kernels. In this study, defoliation treatments at pollinating time were used to simulate loss of photosynthetic area. The treatments changed the amylose‐amylopectin ratios of the endosperm only slightly. The removal of the 6 upper leaves at pollinating time reduced the amylose percentage in high‐amylose inbred lines and hybrids by 1 to 3%. While statistically significant, these small reductions would be of little importance in interpreting the results from an inheritance study of amylose synthesis in corn.
Teaching Techniques Integrating New Developments in Agronomy1
Authors: Lynd J. Q. , Mitchell Roger , Miller D. A. , Allen B. L.
Published: July 2010

Improved teaching techniques are essential for integrating the rapid expansion of new knowledge within agronomic sciences. The time lag in publication of texts results in distinct gaps between research information and classroom applications. There is great need for close cooperation among the several educational and research divisions of the societies in preparation of instructional materials.

Methodology for attaining improved‐updated instruction are presented for the new comprehensive soil classification system, improved techniques for soil and plant nutrient: deficiency diagnosis and soil pesticide interactions.
Effect of Reflective Coatings on Soil Temperatures, Soil Moisture, and the Establishment of Fall Bell Peppers1
Authors: Gerard C. J. , Chambers G.
Published: July 2010

Reflective coatings when applied to modify the soil surface were effective in maintaining favorable soil temperatures and in suppressing evaporation for establishing plant stands. A high inverse relationship was obtained between soil temperatures at planting depth and stand establishment of fall bell peppers. Soil temperatures at 45 C to 47 C at planting depth prevented germination of peppers. Certain coatings were effective in suppressing soil temperatures below 43 C at planting depth and in providing a favorable environment for germination of fall peppers. The data suggest that the use of 41 to 61 liters/are (10 to 15 gal/1000 ft2) of better reflective coating materials adequately suppress evaporation and insure desired plant population of peppers. Pepper yields were a function of stand with the peppers growing under the better coatings producing about 5 metric tons per hectare or over five times the yield on the multi‐irrigated bare plots.
Surface Drainage Research: I. Bedding as Evaluated by Corn Response Under Two Fertility Levels on a Very Fine Textured Aeric Ochraqualf1
Authors: Rykbost K. A. , Zwerman P. J. , Lucey R. F.
Published: July 2010

Two‐year results show similar yields for nonbedded and bedded treatments. Bedding depressed silage yields 2.5 metric tons/ha and increased yield of grain in silage 190 kg/ha. Average precipitation in the fall of 1962 prevented the mechanical harvest of corn on 50% of the nonbedded and 5% of the bedded area due to wet soil conditions. After average spring precipitation in 1963, bedded areas dried faster and were planted 1 week earlier than nonbedded areas. This difference in planting date influenced yield and maturity. The application of 101 kg/ha of N, 29 kg/ha of P, and 28 kg/ha of K increased silage yield and grain in silage 13.4 tons/ha and 1750 kg/ha respectively. Mean silage yields at 1.8 meter increments from the center of the bed channel to the crown were 9.2, 18.4, 28.2, 35.2, 39.6, 41.5, 41.9, and 48.6 tons/ha. Response to the fertilizer treatment over the same spacing increments were 12.3, 14.6, 21.5, 18.8, 16.8, 11.6, 15.2, and 12.3 tons/ha of silage. Effect of fertilizer on grain in silage followed similar trends.
Effect of Radial Restriction on Lateral Growth of the Root‐Shoot Axis of Young Cotton Plants1
Authors: Mathers Aubra C.
Published: July 2010

Cotton was grown in the greenhouse with restrictions at the root‐shoot axis. These restrictions were produced by puddling the soil, which subsequently dried to form a high‐strength layer, or by using plexiglass clamps. They were created to simulate restrictions observed in the field so that observations could be made of cell injury caused by restriction of lateral growth.

Observations of cross sections from these cotton plants indicated that both xylem and phloem cells formed after lateral growth was restricted were smaller than normal. Phloem cells already present were damaged by pressure exerted by cell division that occurred after plants were restricted.
Portable Equipment for Weighing Sweet Sorghum Stalks from Small Plots1
Authors: Coleman Otto H. , Broadhead Dempsey M.
Published: July 2010

Portable equipment is described for use in weighing sweet sorghum stalks from small experimental plots. The three‐point base fits irregular soil surfaces. One man can easily transport this light (about 15.4 kg) equipment that weighs up to 34 kg.
Punch Planting to Establish Lettuce and Carrots Under Adverse Conditions1
Authors: Cary J. W.
Published: July 2010

It was observed in both the greenhouse and field that lettuce and carrots may be established by planting single seeds in holes punched through the soil crust. When the holes are not back‐filled, seeds planted as deep as 60 mm will produce healthy plants in a few days. Preliminary experiments indicate that in some climatic regions a practical field management system could be developed which will eliminate emergence problems arising from soil crusting and premature drying of shallow seedbeds. The open hole punch method may also prove useful in controlling the temperature and salinity adjacent to the seed and in reducing initial tillage and irrigation requirements.
Effect of Continuous Submergence Versus Alternate Flooding and Drying on Growth, Yield, and Nitrogen uptake of Rice1
Authors: Patrick W. H. , Quirk W. A. , Peterson F. J. , Faulkner M. D.
Published: July 2010

A comparison was made of rice (Oryza saliva) grown under continuously submerged conditions and under alternately dry and flooded conditions in several greenhouse and field experiments. With nitrogen‐deficient soils, alternately dry and submerged conditions caused an appreciable decrease in growth, yield, and nitrogen uptake. With soils high in available nitrogen as a result of being in permanent pasture for several years, drying and reflooding resulted in a yield increase. Drying and reflooding apparently resulted in a loss of soil nitrogen which was detrimental in the nitrogen‐deficient soils and beneficial in the soils that had been in pasture.
Castorbean Yield and Quality as Influenced by Irrigation Schedules and Fertilization Rates1
Authors: Kittock D. L. , Williams J. H. , Hanway D. G.
Published: July 2010

Irrigation of the growing crop in addition to preplant irrigation did not significantly increase yields of castorbeans (Ricinus communis L.) in 2 of 3 years. In 1963 one irrigation on July 25 produced yields that were significantly higher than either no postplant irrigation or six weekly irrigations. Delay of first irrigation 14 days reduced yields significantly. High nitrogen (180 kg/ha) significantly increased yields of ‘Baker 296’ variety, but not of ‘Lynn,’ grown only in 1963. Irrigation treatments had a significant effect on field loss of seed of Lynn. Highest field losses were from treatments receiving the earliest irrigation. Baker 296 seed losses were lower and differences between treatments were not significant. Nitrogen level had no significant effect on field loss. Weight per 100 seeds and oil content were inversely related to amount of irrigation water applied. Added nitrogen significantlty reduced Alternaria leaf spot infection. In the no‐irrigation treatment soil moisture approached the permanent wilting point in the 30‐ to 61‐cm depth of soil in late August, in the 91‐ to 122‐cm depth in late September, and significant utilization of soil moisture in the 152‐ to 183‐cm depth was evident in early September.
A Micro‐Digestion Procedure for the Determination of Aminoid Nitrogen in Plant Material1
Authors: Qashu Hasan K.
Published: July 2010

Plant material from two brush species, Ceanothus crassifolius and Adenostoma fasciculatum, was analyzed for aminoid N content using three different digestion procedures. A micro‐digestion procedure in a sealed tube gave higher organic nitrogen recovery than two standard Kjeldahl digestion methods. Partial recovery of nitrate N was found when standard digestion procedures were used, but no nitrate N recovery was apparent from the sealed tube method.
An Experimental Plot Planter for Peanuts, Arachis hypogaea L.1
Authors: Culp Thomas W.
Published: July 2010

A two‐row Cole planter was modified to seed experimental plots of peanuts. A spring‐clutch is inserted in the drive shaft to disengage the seed plate assembly and the drive wheel. A hand‐crank is attached to the drive shaft above the slip‐clutch. When the crank is turned, the seed plate spins and expels the seed from the hopper. Thus, the seed hopper can be rapidly cleaned of remnant seed after each plot is planted.
Effects of Temperature and Soil Moisture on Single vs. Split Nitrogen Applications to Rye (Secale cereale L.) Forage1
Authors: Cummins D. G. , Burns R. E. , Smart W. W. G.
Published: July 2010

Nitrogen was applied in single and split applications at rates of 0, 300, and 600 mg per pot (equivalent to 0, 50, and 100 pp2m) to rye grown in a growth chamber at 10 and 21 C. Low and high soil moisture levels were maintained by watering to field capacity when soil moisture reached 15 and 60% of field capacity. Responses to these variables were measured by forage yields, total N uptake, and percent N in the plants.

With either low temperature or low soil moisture, higher forage yields were obtained with single N applications. Only under both high temperature and high soil moisture was it advantageous to split N. With high soil moisture, split N improved yields in the second harvest. This would, in effect, extend the grazing period. Soil moisture was more limiting to growth in the first harvest, while temperature was more limiting in the second harvest.

When N was applied in a single application, plant uptake (mg N per pot) was usually greater than or equal to treatments with split applications.

Plant N content at 21 C was higher with single N applications but at 10 C was higher with split applications. Generally, low soil moisture increased N content of the forage compared with high soil moisture.

The variable responses to N obtained under different temperatures and soil moisture levels will aid in interpreting field results.
Yield of Corn Grain as Affected by Fertilizer Rates and Environmental Factors1
Authors: Voss Regis , Pesek John
Published: July 2010

Eighteen experiments were conducted on the Clarion, Nicollet, and Webster soil series in Iowa to determine which selected measureable soil, management and weather factors affect the yield and response of corn grain to applied N, P, and K in multirate experiments and to quantify these combined effects through multiple regression analyses. The unfertilized plot grain yields were related to soil test values for N. P. K. and pH; time of planting; yielding ability of the corn hybrids planted; plant population and weather as characterized by a stress day criterion based on moisture depletion of the rooting zone. Soil pH and soil sources of N, P, and K; time of planting; plant population; yielding ability of the hybrids; and the stress days in the 5 weeks following planting affected the yield response to applied nutrients as indicated by multiple regression analyses.

Methods for determining which factors affected yield and response to applied nutrients are described. The effect of a measurable uncontrolled factor on the response to an applied nutrient was determined by examining the slopes of the n‐dimensional yield surface.
Influence of Plant Spacing and Population on Aspects of the Microclimate within Corn Ecosystems1
Authors: Colville W. L.
Published: July 2010

Three experiments were designed to evaluate the influence of planting pattern (drilled, hill‐dropped, and checked) and plant population on the microclimate of corn. Data were collected on an hourly basis between 0600 and 2400 hours for a period of days following pollination. The quantity of light reaching the soil through the leaf canopy was statistically greater under hilled than drilled corn, diminished with increasing plant population but remaining stable at populations of 49,400 or more plants per hectare. Light was the only factor influenced significantly by planting patterns. Soil temperatures at a depth of five centimeters under a stand of 69,160 plants/ha were reduced 10 C and under a stand of 19,760 by 5.5 C (at 1400 hours) compared to an outside bare soil location. Air temperatures within ecosystems were not greatly modified by population or method of planting. Relative humidity increased with increasing plant population. Microclimate readings were affected by the time at which the reading was taken.
Relationships between Five Laboratory Stress Tests, Seed Vigor, Field Emergence, and Seedling Establishment in Reed Canarygrass1
Authors: Mark Jerry Lee , McKee Guy W.
Published: July 2010

Field emergence and seedling growth from spring and summer plantings of 21 seed lots of reed canarygrass were compared with germination results from four stress tests (cold flood, hot flood, accelerated aging, and acid) and with the standard laboratory germination test. For the 21 seed lots, results of all tests were significantly correlated with each other and with field emergence and fall dry‐top weight. Germination following either the hot flood test or the cold flood test was a better indicator of actual field performance than the standard germination test alone. Considering speed and convenience of testing as well as relation to field performance, a combination of standard laboratory germination test and hot flood test was superior to either alone or to other test combinations. The standard laboratory germination test percentage multiplied by 0.33 provided a fairly adequate evaluation of field emergence, somewhat underestimating emergence under relatively favorable environmental conditions and slightly overestimating emergence under less favorable environmental conditions. Seed lots which were comparable in germination on the standard germination test and which were no more than a year old were variable in vigor and in field performance. In contrast, seed lots 3 or more years old were consistent in performance on the several tests although their vigor was reduced compared to seeds 1 year old.
Effect of Corn Population and Simazine on Weed Growth1
Authors: Eplee Robert E. , Klingman G. C.
Published: July 2010

Five rates of 2‐chloro‐4,6‐bis(ethylamino)‐s‐triazine (simazine) were applied both preemergence and at lay‐by to five levels of corn (Zea mays L.) populations. Increased weed control resulted from the combination of corn competition and the herbicide simazine. This increased weed control may be associated with a competitive advantage given to the corn and/or the effect of shading upon the retention of the herbicide on the soil surface. Corn 46 cm tall significantly reduced weed growth with additional suppression obtained from simazine. It is proposed that shading may reduce soil temperatures, which in turn may reduce the loss of simazine through photodecomposition and/or volatilization.
Herbicides or Oat Companion Crops for Alfalfa Establishment and Forage Yields1
Authors: Kust Cyril A.
Published: July 2010

‘Vernal’ alfalfa (Medicago sativa L.) was established with herbicides in 1964, 1965, and 1966 at the University of Wisconsin Arlington Experimental Farm. The objective was to determine the forage yields that could be obtained from a pure alfalfa stand in the seeding year and to compare them with yields that have been obtained from oat companion crops removed at an immature stage for silage or hay. The assumption was that the previous alfalfa stand had been destroyed by winter killing and that maximum forage production per acre in the seeding year was of prime importance. Alfalfa established with herbicides was comparatively unproductive during the seeding year and much higher forage yields were obtained when alfalfa was established with an oat companion crop and both harvested as forage.
Seed Soaking As A Pre‐Sowing, Drought‐Hardening Treatment in Wheat and Barley Seedlings1
Authors: Salim M. H. , Todd Glenn W.
Published: July 2010

The effect of seed soaking treatment of winter wheat (Triticum aestivum L.) was investigated using distilled water or nine other dilute solutions — CaCl2, ZnSO4, Fe2(SO4)3, adenine, gibberellic acid, vitamin K3, 2,4‐D, and garlic extract. Three wheat varieties and two barley (Hordeum vulgare L.) varieties were also subjected to seed pre‐sowing treatment in water or 0.25% CaCl2 solution.

The seedlings were tested at 3 to 4 weeks of age for desiccation resistance, transpiration, germination and growth in mannitol, and recovery. CaCl2 solution, 0.25%, seemed to be somewhat effective in inducing more desiccation resistance in wheat, with the ‘Ponca’ variety showing the highest response and ‘Red Chief’ the lowest. In barley, water or CaCl2 induced better water retention in ‘Ward’ variety only. No response was detected in ‘Rogers.’ Seed pre‐soaking in 2,4‐D caused a decrease in desirable xeromorphic features. Most of the other treatments had either no effect or undesirable effects.

It is concluded that no generalized statement as to the effect of pre‐sowing seed treatment can be made since the response seems to depend upon the treatment and variety used. This may help to explain some of the contradictory results reported in the literature.
Effect of Skip‐Row Culture on Agronomic and Fiber Properties of Upland Cotton (Gossypium hirsutum L.) Varieties1
Authors: Hawkins B. S. , Peacock H. A.
Published: July 2010

Average lint yields of eight varieties of Upland cotton (Gossypium hirsutum L.) planted in 1963 and 1964 in solid and 2×2 skip‐row designs showed a significant yield increase in favor of skip‐row planting. Yields from skip‐row planting were 30 and 61% greater in 1963 and 1964, respectively, than yields from solid planting. Yields are reported on an allotted hectare basis.

Comparison of average lint yields of all varieties planted in tests from 1959 to 1964 (no test planted in 1961) showed a significant (P=.01) over‐all increase 42% in favor of skip‐row planting. Differential varietal response to method of planting on lint yields was indicated by significant (P=.01) variety) × method interaction for four varieties studied for 5 years. A significandy (P=.01) greater percentage of total seed cotton was harvested at first picking from solid than from skip‐row planting.

Bolls from the skip‐row planting were significantly (P=.01) larger than bolls from solid planting in the 1959–1964 tests. Fiber length increased significantly (P=.05) on varieties grown in the skip‐row design, but mean length, strength, and fineness were unaffected by method of planting.
Growth of Roots of Seven Varieties of Spring Wheat at High and Low Moisture Levels1
Authors: Hurd E. A.
Published: July 2010

Seven varieties of spring wheat, T. aestivum L., were grown at two levels of moisture in glass‐faced boxes. Weekly measurements, made of the roots showing on the glass, and the total weight at each depth were required to determine the root pattern. Four of the varieties were grown in both Weyburn Oxbow Loam and Regina Heavy Clay. Yield of ‘Thatcher’ was reduced less by moisture stress than that of other varieties. Roots of Thatcher penetrated the soil more quickly in dry soil than in wet soil and more quickly than other varieties tested at both moisture levels. When soil dried out in surface layers, root growth of Thatcher increased in the moist layer just below. Two lines developed for the Canadian Prairies were similar to Thatcher but yielded slightly less when moisture stress was high. ‘Nainari 60,’ ‘Lemhi 53,’ and especially ‘Koga II’ produced more roots at high levels of moisture than Thatcher but suffered more under moisture stress. ‘Narino 50’ was earlier and lower yielding but suffered less from moisture stress than most varieties tested. The pattern of roots of the different varieties help to explain their yield performances at different moisture levels. The loam soil was more satisfactory to use in root studies than the clay soil, as it tended to accentuate the differences in response to high and low levels of moisture.
Effect of Oil Treatment of Fertilizers on Crop Yields and Uptake of Fertilizer Constituents1
Authors: Thompson S. O. , Wedin W. F. , Attoe O. J.
Published: July 2010

The addition of up to 5% of fuel oil to fertilizers to reduce dustiness and caking had little or no effect on yield and uptake of N, P and K by greenhouse grown oats. Similar results were obtained for field grown corn and for greenhouse and field grown tobacco.
Response of Sudangrass Hybrids to Cutting Practices1
Authors: Holt Ethan C. , Alston George D.
Published: July 2010

Two sorghum ✕ sudangrass hybrids were planted in rows I m wide and cut at three stages of development (frequencies) and three stubble heights. Location of apical and secondary meristems at cutting and origin and type of regrowth were recorded as well as yield and total growth. Best forage yields were obtained with less frequent harvest and shorter stubble heights, but stubble height within frequencies did not influence total plant development (forage yield + stubble weight). The number of primary growth primordia left in the stubble increased with greater stubble heights and with earlier harvest stages. The number of secondary meristems remaining after second cutting increased both with greater stubble height and later harvest stages. Tillering was greater with short stubble, while aerial branching increased with stubble height and later stages of maturity. These results suggest that for maximum forage yields, the plants should be allowed to grow long enough between cuttings to fully recover. The most favorable cutting height for forage yield removes the apical meristems and most of the secondary meristems and results in primarily tiller growth. Total carbohydrates increased in the initial growth to the early flowering stage. Although carbohydrates were expended (disappeared) during regrowth, there seemed to be no actual relationship between carbohydrate percentage and yield.
Seedbed Design for Minimizing Sugar Beet (Beta vulgaris) Seedling Damage by Mild Radiation Freeze1
Authors: Mayland H. F. , Cary J. W.
Published: July 2010

Greenhouse and field tests were made to evaluate the frost protection afforded by various seedbed designs. Planting in pockets was the most effective in reducing radiative freeze damage to sugar beet (Beta vulgaris) seedlings in the two‐leaf stage. Pockets were 7.5 cm in diameter by 5 cm deep, formed at 45° to the horizon in 45° south‐facing slopes on sides of 20‐cm‐high soil ridges. During freeze periods, leaf temperatures of the plants in the pockets averaged 3.4 C and 2.2 C higher than leaf temperatures of plants in the conventional seedbed under greenhouse and field conditions, respectively. Temperature differences were not as great under field conditions because of low soil temperatures. The planting system could, however, add 2 weeks to the spring growing season for sugar beets in southern Idaho, provided soil temperatures are high enough for germination.
Effect of Row and Within‐Row Spacings on Yield and Quality of Flue‐Cured Tobacco1
Authors: Chaplin J. F. , Ford Z. T. , Pitner J. B. , Currin R. E.
Published: July 2010

Two experiments were conducted to study the effects of spacing on the cured leaf of flue‐cured tobacco. One involved different numbers of skipped rows and the other involved plant spacings within the row. Yields increased as the number of skipped rows increased. Also, the value per 45.35 kg increased as the number of skipped rows increased, which may indicate a better quality of tobacco produced with the wide rows. Alkaloid content was somewhat lower as the number of skipped rows increased, and the filling value decreased as the number of rows increased. In comparing the common practice of planting four rows and skipping one to the older method of continuous rows, there seemed to be little difference in the cured leaf for reducing sugars, total alkaloids, filling value, or equilibrium moisture content. However, an increase in yield (92 kg) and value per hectare ($188.00) was obtained by skipping every fifth row. In general, the more plants per acre the greater the yield when the plants were topped to a common leaf number. Wider spacings within the row gave the higher value per 45.35 kg; however, there was no difference between the 61‐ and 69‐cm spacing. There was little difference in reducing sugars for any of the spacings, but there was a tendency for alkaloids to increase as spacings increased. Distance between plants in the row seemed to have little effect on filling value and equilibrium moisture content. Results indicate that above 61‐cm spacing in the row is too wide and that close spacing although producing more money return per hectare may tend to reduce the quality of the cured leaf.
Organic Matter Removal from Liquid Peach Waste by Percolation Through Soil and Interrelations with Plant Growth and Soil Properties1
Authors: Hunt Patrick G. , Peele T. C.
Published: July 2010

Peach cannery waste of three concentrations was applied to Cecil sandy clay loam and Lakeland sand in lysimeters on which Coastal bermudagrass was growing. The soil was artificially placed in the lysimeters to simulate subsoiling to a depth of 50.8 cm. The waste was applied at a rate of 2.54 cm/hr with total amounts of 7.62 cm twice a week. No ponding was observed, indicating an infiltration rate of at least 2.54 cm/hr. A total of 82.55 cm of waste was applied during the season. The BOD (biochemical oxygen demand) was reduced 98% by the Cecil and 64% by the Lakeland soil. Yield of the grass decreased somewhat as the waste concentration increased but was larger in all cases than non‐irrigated grass. Application of the waste increased the exchangeable sodium in the soil but no appreciable effect on soil structure was found.
Variation in Foam Production by Plants of ‘Vernal’ Alfalfa1
Authors: Rumbaugh M. D.
Published: July 2010

A simplified technique to evaluate in vitro foam‐producing capabilities of forage plants is described. The method was successfully used to examine 100 unselected clones of ‘Vernal’ alfalfa (Medicago sativa L.). Sufficient variation was observed to believe the technique may be useful in selecting and breeding cultivars with low foam producing capabilities and possibly low bloat probability of grazing ruminants.