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Structural, Functional And Biochemical Responses Of Datura Innoxia Mill. To Coal-Smoke Pollution, Azamal Husen, Muhammad Iqbal Jan 1999

Structural, Functional And Biochemical Responses Of Datura Innoxia Mill. To Coal-Smoke Pollution, Azamal Husen, Muhammad Iqbal

Dr. Azamal Husen

Effect of coal-smoke pollution on Datura innoxia Mill. was investigated. D. innoxia has shown that leaf length, single leaf area, total leaf area and leaves per plant decreased but leaf biomass increased under pollution stress. Epidermal features of upper and lower leaf surface responded to pollution stress differently. Rate of photosynthesis and stomatal conductance were low, internal CO2 concentration was high and levels of chlorophyll a and b, total chlorophyll and carotenoids were reduced in polluted condition. Levels of proteins, reducing sugar in roots and sulphur contents in leaves, stem, roots and seeds showed significant increase under the polluted condition. …


A Comparison Of Three Methods For Determining Root-Knot Nematode Infection Of Cotton Roots, Robert G. Mcbride, Robert Mikkelsen Jan 1999

A Comparison Of Three Methods For Determining Root-Knot Nematode Infection Of Cotton Roots, Robert G. Mcbride, Robert Mikkelsen

Robert Mikkelsen

Three methods for determining the extent of infection of cotton roots (Gossypium hirsutum L.) by root-knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood, were compared. Root-knot nematode eggs were added to pots containing either sterilized soil or soil amended with rye, and cotton seedlings were planted. Cotton root systems were then assessed for infection/damage after 14 and 28 days of exposure. At the 14-day sampling, the roots were stained, using the lactophenol acid fuchsin method and the juvenile nematodes counted. At the 28-day samplings, the cotton roots were given a visual rating for nematode-induced root galling (0-100), and the galls …


Variation In Competitive Abilities Of Plants And Microbes For Specific Amino Acids, David A. Lipson, Ted K. Raab, Steven K. Schmidt, Russ K. Monson Jan 1999

Variation In Competitive Abilities Of Plants And Microbes For Specific Amino Acids, David A. Lipson, Ted K. Raab, Steven K. Schmidt, Russ K. Monson

Ted K. Raab

Microbes are assumed to possess strong competitive advantages over plants for uptake of nutrients from the soil. The finding that non-mycorrhizal plants can obtain a significant fraction of their N requirement from soil amino acids contradicts this assumption. The amino acid glycine (Gly) has been used as a model amino acid in many recent studies. Our preliminary studies showed that Gly was a poor substrate for microbial growth compared to other amino acids. We tested the hypothesis that the alpine sedge Kobresia myosuroides competes better for Gly than for other amino acids because of decreased microbial demand for this compound. …


Isolation Of A Mannose-Binding And Ige- And Igm-Reactive Lectin From The Seeds Of Artocarpus Integer, Onn Haji Hashim Jan 1997

Isolation Of A Mannose-Binding And Ige- And Igm-Reactive Lectin From The Seeds Of Artocarpus Integer, Onn Haji Hashim

Onn Haji Hashim

A mannose-binding lectin, termed champedak lectin-M, was isolated from an extract of the crude seeds of champedak (Artocarpus integer). On gel filtration chromatography, the lectin eluted in a single peak at elution volumes corresponding to 64 kDa, SDS-PAGE showed the mannose-binding lectin to be composed of 16.8 kDa polypeptides with some of the polypeptides being disulphide-linked to give dimers. When tested with all isotypes of immunoglobulins, champedak lectin-M demonstrated a selective strong interaction with human IgE and IgM, and a weak interaction with IgA2, The binding interactions of lectin-M were metal ion independent. The lectin was also shown to interact …


Pollen Dispersal In Low-Density Populations Of Three Neotropical Tree Species, Jason D. Nason, E. A. Stacy, J. L. Hamrick, S. P. Hubbell, R. B. Foster, R. Condit Aug 1996

Pollen Dispersal In Low-Density Populations Of Three Neotropical Tree Species, Jason D. Nason, E. A. Stacy, J. L. Hamrick, S. P. Hubbell, R. B. Foster, R. Condit

Jason D Nason

Studies of mating patterns of tropical trees, typically involving common species, have revealed that most species are outcrossed and that, in some cases, a significant reaction of outcross pollen moves long distances. We evaluated mating systems and effective pollen dispersal for three hermaphroditic insect-pollinated Neotropical tree species, Calophyllum longifolium, Spondias mombin and Turpinia occidentalis, all of which occurred at low adult densities at the study site. Mating patterns were estimated for each maternal tree within 84-ha populations of C. Longifoliuman d S. mombin in 1992 and 1993 and within a 50-ha population of T. occidentalis in 1993. Each population was …


Non-Mycorrhizal Uptake Of Amino Acids By Roots Of The Alpine Sedge Kobresia Myosuroides: Implications For The Alpine Nitrogen Cycle, Ted K. Raab, David A. Lipson, Russ K. Monson Jan 1996

Non-Mycorrhizal Uptake Of Amino Acids By Roots Of The Alpine Sedge Kobresia Myosuroides: Implications For The Alpine Nitrogen Cycle, Ted K. Raab, David A. Lipson, Russ K. Monson

Ted K. Raab

Non-mycorrhizal plants of the alpine sedge, Kobresia myosuroides , take up the amino acid glycine from nutrient solutions at greater rates than NO3- or NH4+. The amino acids glutamate and proline were also taken up at high rates. Total plant biomass was twice as high after 4 months of growth on glycine, compared to NH4NO3, with significant increases in both root and leaf biomass. By taking advantage of differences in the d13C signature of air in the growth chamber and the glycine used for growth, a two-member mixing model was used to estimate that a significant amount of the glycine …


Swine Waste Disposal Dilemma, Robert Mikkelsen Jan 1995

Swine Waste Disposal Dilemma, Robert Mikkelsen

Robert Mikkelsen

The swine industry has grown rapidly in North Carolina in the past decade, with the majority of the growth occurring in a few counties in the Coastal Plain region of the state. With this expansion has come the problem of swine waste disposal. Mr. Blevins, a local farmer in this region, has been raising swine since 1985. The swine waste on his farm is collected in an anaerobic lagoon and then irrigated onto a bermudagrass (Cynodon dactylon(L.) Pers.) pasture where cattle are fed using intensive rotational grazing techniques. A study of Mr. Blevins' farm revealed very high nitrate concentrations in …


A Memorable Meeting, February 1994, Fathi Habashi Feb 1994

A Memorable Meeting, February 1994, Fathi Habashi

Fathi Habashi

Decision taken at the Steering Committee Meeting of the International Mineral Processing Congress in San Francisco February 1994 to name the IMPC Award.


Using Hydrophilic Polymers To Control Nutrient Release, Robert Mikkelsen Jan 1994

Using Hydrophilic Polymers To Control Nutrient Release, Robert Mikkelsen

Robert Mikkelsen

Using diverse technological approaches, many types of delivery devices have been used to supply plant nutrients at a controlled rate in the soil. One new approach is the use of hydrophilic polymers as carriers of plant nutrients. These polymers may be generally classified as 1) natural polymers derived from polysaccharides, 2) semi-synthetic polymers (primarily cellulose derivatives), and 3) synthetic polymers. By controlling the reaction conditions when forming the polymers, various degrees of cross-linking, anionic charge, and cationic charge can be added, thereby changing their effectiveness as fertilizer carriers. When fertilizer-containing solutions are mixed with hydrophilic polymers to form a "gel" …


Addition Of Gel-Forming Hydrophilic Polymers To Nitrogen Fertilizer Solutions, Robert Mikkelsen, A David Behel Jan 1993

Addition Of Gel-Forming Hydrophilic Polymers To Nitrogen Fertilizer Solutions, Robert Mikkelsen, A David Behel

Robert Mikkelsen

Environmental and economic concerns are causing a search for more effective fe rtilizer products and improved methods for managing existing fertilizers. This laboratory and greenhouse study was conducted to determine if the addition of gel-forming hydrophilic polymers to N fertilizer solutions could reduce N leaching loss and increase plant uptake of N. In the first experiment, a solution of urea ammonium nitrate (UAN, 32% N) was mixed with a variety of polymers at three concentrations, band applied to a sandy soil, and leached weekly for six weeks. Nitrogen leaching losses were reduced from 0 to 45% during the first four …


Controlled-Release Fertilizers To Increase Efficiency Of Nutrient Use And Minimize Environmental Degradation - A Review, Avi Shaviv, Robert Mikkelsen Jan 1993

Controlled-Release Fertilizers To Increase Efficiency Of Nutrient Use And Minimize Environmental Degradation - A Review, Avi Shaviv, Robert Mikkelsen

Robert Mikkelsen

Total world consumption of fertilizer N, P2 O5, and K2O in 1990 / 1991 was 78. 37. and 26 million tons per annum respectively, with a projected yearly increase of demand of about 2 to 3% . Trends in crop production (maize and wh eat) in the last four decades s how that N application rates increased about 15 times whereas its accumulation in grain increased only 3 to 4 times. At the same time nutrient recovery by crops remained relatively low (e .g. a bout 50% for N). This represents a potentially alarming situation from environmental, economic and resource …


The Effect Of Selenium On Sulfur Uptake By Barley And Rice, Robert Mikkelsen, Hongfu Wan Jan 1990

The Effect Of Selenium On Sulfur Uptake By Barley And Rice, Robert Mikkelsen, Hongfu Wan

Robert Mikkelsen

Because of their chemical and physical similarities, plant uptake of sulfur and selenium are closely related. Barley and rice were grown in greenhouse solution culture to examine the synergistic interactions between sulfate and selenate in plant uptake. In the presence of low concentrations of solution sulfate, shoot and root yields were decreased with additions of selenate. However, when sulfate was present in elevated concentrations, no selenium-induced yield reductions occurred. A synergistic interaction between sulfate and selenate caused an increase in the shoot sulfur concentrations with increasing concentrations of selenate at low sulfate solution concentrations. At elevated sulfate concentrations, no synergism …


Biuret In Urea Fertilizer, Robert Mikkelsen Jan 1990

Biuret In Urea Fertilizer, Robert Mikkelsen

Robert Mikkelsen

Urea has become the leading form of N fertilizer worldwide. Historically there has been concern about biuret formed during the manufacturing of urea fertilizer and the potential adverse effect of biuret on plant growth. In this paper, the fate of biuret in soils and its phytotoxicity is reviewed. Biuret is mineralized by many soil micoorganisms, but the process is much slower than for urea. Excessively high biuret concentrations can damage seedlings and, like urea, should not be placed in close proximity to germinating seeds. Crop tolerance to biuret varies according to the plant species, soil conditions, fertilizer placement, and method …


Presence Of A Cs-Resistant Transient Outward Current Which Distorts Ica Measurements In Guinea-Pig Single Ventricular Cells, Georges Christé, Brigitte Delachapelle, Fouad Lemtiri-Chlieh, Carlos Ojeda Nov 1989

Presence Of A Cs-Resistant Transient Outward Current Which Distorts Ica Measurements In Guinea-Pig Single Ventricular Cells, Georges Christé, Brigitte Delachapelle, Fouad Lemtiri-Chlieh, Carlos Ojeda

fouad Lemtiri-Chlieh

To correctlyr analyse the physical properties of ion channels and the actions of drugs upon them, it is important that the membrane conducts only the ionic species believed permeant. In guinea-pig ventricular cells it has been assumed that only ICaL flows in the potential range -50 to +60 mV in the presence of intra- and extracellular Cs (> 20 mM). We report here that this is not the case due to the presence of a Cs-insensitive, transient outward current.


Measurements Of Cytosolic Free Ca In Cultured Rat Neonate And Adult Guinea-Pig Ventricular Cardiac Myocytes, Jean-Claude Bernengo, Fouad Lemtiri-Chlieh, Carlos Ojeda, Nadine Pltonoff Nov 1989

Measurements Of Cytosolic Free Ca In Cultured Rat Neonate And Adult Guinea-Pig Ventricular Cardiac Myocytes, Jean-Claude Bernengo, Fouad Lemtiri-Chlieh, Carlos Ojeda, Nadine Pltonoff

fouad Lemtiri-Chlieh

Cytosolic free Ca was measured with Indo-1 (Grynkiewicz et al. 1985) as free acid (in guinea-pig cells) or as the ester (in rat neonate cells). Using image analysis we obtained concentration maps at 40 ms intervals at two wavelengths (Cannell et al. 1986). In rat neonate cells, at rest and during contraction, calcium was apparently non-uniformly distributed, in contrast to guinea-pig adult cells. Using a dual PM spectroscopic system adapted to an inverted microscope we found: (1) the conversion of Indo-AM to Indo- 1 in the cytosol is not complete (< 40% contribution to the total light); (2) rat neonate cells buffer Ca (at rest 130-170 nM) only for [Ca]. between 1 and 3 mM, whereas in adult guinea-pig cells the range extended to 10 mM; (3) during contraction [Ca]i rose from 200 nm to no more than 1 microM. Digitoxin increases basal and peak [Ca]i; (4) during spontaneous contractions, in guinea-pig cells, [Ca]i rises from 70 to 200 nm when [Ca]o = 0, and from 170 nm to about 1 microM when [Ca]o = 2 mM; (5) in voltage-clamp conditions the rise in [Ca]i does not exceed 2 microM and oscillations occur in the presence of forskolin. When loading with Indo-1, cells frequently cease to contract (Powell et al. 1988) and the variations in [Ca]i are then very small (about 200 nm at peak ICa). In both cases these values are small compared to the total charge crossing the membrane.


Phosphorus Fertilization Through Drip Irrigation, Robert Mikkelsen Jan 1989

Phosphorus Fertilization Through Drip Irrigation, Robert Mikkelsen

Robert Mikkelsen

Although P fertilization through drip irrigation systems has not been widely recommended, a review of currently available literature indicates this fertilizer application technique can offer many advantages when performed properly. Using drip irrigation to apply P fertilizer allows nutrient placement directly into the plant root zone during critical periods of nutrient demand. Less P fertilizer is generally required to achieve sufficient tissue P concentrations and equivalent yields when it is drip-applied than with other application methods. The distribution of drip-applied P in soil depends on soil properties, the source of P fertilizer, the rate of application, and the amount of …


Factors Affecting Selenium Accumulation By Agricultural Crops, Robert Mikkelsen, Albert L. Page, Frank T. Bingham Jan 1989

Factors Affecting Selenium Accumulation By Agricultural Crops, Robert Mikkelsen, Albert L. Page, Frank T. Bingham

Robert Mikkelsen

The accumulation of selenium by plants is of concern worldwide. Many regions grow crops that contain insufficient Se to meet animal nutritional requirements. In these locations with low Se, efforts have been made to increase tissue Se concentrations. Other areas have problems with excessive Se found in vegetation grown on seleniferous soils. Plant species vary in their ability to accumulate and tolerate Se. Selenium accumulator plants can accumulate extremely high Se concentrations (several thousand mg Se kg-1) when grown in seleniferous soils, whereas typical agricultural crops have a much lower Se tolerance (<50 mg Se kg>-1 ). It has been suggested that …


Application Of Urea Phosphate And Urea Sulfate To Drip-Irrigated Tomatoes Grown In Calcareous Soil, Robert Mikkelsen, Wesley Jarrell Jan 1987

Application Of Urea Phosphate And Urea Sulfate To Drip-Irrigated Tomatoes Grown In Calcareous Soil, Robert Mikkelsen, Wesley Jarrell

Robert Mikkelsen

The potential benefit of acid applied through drip urrigation on soil nutrient availability, plant nutrition, and yield was studied. Tomatoes (Lycopersicon esculentum Mill., cv. Better Boy) were grown in a P-deficient calcareous loam soil in 114-L plastic-lined cans. Phosphorus was added weekly through drip irrigation as urea phosphate (UP) (17-19-0) at four concentrations (0, 20, 40, 80 kg P/ha). Two other treatments entailed 40 kg P/ha soil-banded triple superphosphate (TSP) (0-20-0) with or without the addition of drip­ applied urea sulfate (US) (15-0-0-16). Urea sulfate was added at the rate equivalent to the titratable acidity of the 40 kg UP-P/ha …


Influence Of Hormonal Chemicals And Genotypes On Fruit Growth Of Lycopersicon Esculentum, Henry R. Owen May 1984

Influence Of Hormonal Chemicals And Genotypes On Fruit Growth Of Lycopersicon Esculentum, Henry R. Owen

Henry R. Owen

The effects of hormonal chemicals and different genotypes on fruit growth of greenhouse-grown tomatoes ( Lycopersicon esculentum Mill.) were examined. Continuous root application of lOnM N6 -benzylaminopurine in Hoagland's nutrient solution to tomato seedlings of 'Fireball' and 'Red Cherry' significantly delayed anthesis of 'Fireball', but not 'Red Cherry'. Ovary diameter at anthesis, final fruit diameter, and fruit weight of both cultivars were unaffected. Irrespective of treatments, a significant positive correlation was obtained between ovary diameter at anthesis and final fruit diameter. A single foliar application of 0.25mM or 0.37mM 6-naphthoxyaceticacid (betaNOA) at the appearance of the first inflorescence of 'Fireball' …


Tva Fluid Fertilizers Chapter Two - Agronomic Aspects, Eugene C. Sample, Gary W. Akin, Robert Mikkelsen Jan 1984

Tva Fluid Fertilizers Chapter Two - Agronomic Aspects, Eugene C. Sample, Gary W. Akin, Robert Mikkelsen

Robert Mikkelsen

No abstract provided.


Tva Fluid Fertilizers Chapter One- History, Growth, And Status, Robert Mikkelsen Jan 1984

Tva Fluid Fertilizers Chapter One- History, Growth, And Status, Robert Mikkelsen

Robert Mikkelsen

No abstract provided.


Tva Fluid Fertilizers Chapter Four - Chemical Properties, A W. Frazier Jan 1984

Tva Fluid Fertilizers Chapter Four - Chemical Properties, A W. Frazier

Robert Mikkelsen

No abstract provided.


Tva Fluid Fertilizers Chapter Five - Production, Handling, And Use Of Anydrous Ammonia And Status, G. M. Blouin, H. L. Kimborough, W. J. Sharratt Jan 1984

Tva Fluid Fertilizers Chapter Five - Production, Handling, And Use Of Anydrous Ammonia And Status, G. M. Blouin, H. L. Kimborough, W. J. Sharratt

Robert Mikkelsen

No abstract provided.


Hidrometalurjide Yeni, Fathi Habashi Jan 1979

Hidrometalurjide Yeni, Fathi Habashi

Fathi Habashi

Turkish translation of F. Habashi, “Recent Advances in Hydrometallurgy,” Proceedings International Mineral Processing Congress, Warsaw, 1979, edited by J. Laskowski, published by Elsevier, pp. 902–935


Greenhouse Techniques For Soil-Plant-Fertilizer Research, S E. Allen, G L. Terman, L B. Clements, Robert Mikkelsen May 1976

Greenhouse Techniques For Soil-Plant-Fertilizer Research, S E. Allen, G L. Terman, L B. Clements, Robert Mikkelsen

Robert Mikkelsen

PART 2: Special problems and procedures Principles of nutrient uptake in pot experiments


Greenhouse Techniques For Soil - Plant - Fertilizer Research, S E. Allen, G L. Terman, L B. Clements, Robert Mikkelsen May 1976

Greenhouse Techniques For Soil - Plant - Fertilizer Research, S E. Allen, G L. Terman, L B. Clements, Robert Mikkelsen

Robert Mikkelsen

PART 3: Design & sample calculaitons for specific types of experiments Typical greenhouse report References


Greenhouse Techniques For Soil-Plant-Fertilizer Research, S E. Allen, G L. Terman, L B. Clements, Robert Mikkelsen May 1976

Greenhouse Techniques For Soil-Plant-Fertilizer Research, S E. Allen, G L. Terman, L B. Clements, Robert Mikkelsen

Robert Mikkelsen

PART 1: Introduction Greenhouse facilities General techniques


Progress In Extractive Metallurgy, Volume 1. Review By G.N. Dobrokhotov, Fathi Habashi Jan 1975

Progress In Extractive Metallurgy, Volume 1. Review By G.N. Dobrokhotov, Fathi Habashi

Fathi Habashi

Review of the first volume of Progress in Extractive Metallurgy edited by Fathi Habashi and published by Gordon & Breach in New York in 1975. The review was written by Professor Dobrokhotov at the Leningrad Mining Institute.