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elizabeth helfant

Plant Nutrients - 2 views

www.agr.state.nc.us/...nutrient.htm

shared by elizabeth helfant on 19 Apr 10 - Cached
  • The primary nutrients are nitrogen (N), phosphorus (P), and potassium (K). These major nutrients usually are lacking from the soil first because plants use large amounts for their growth and survival. 
    • Maleeha Habib
      Maleeha Habib on 19 Apr 10
       
      Nitrogen is a major nutrient for plant growth and survival
    • elizabeth helfant
      elizabeth helfant on 28 Jun 10
       
      try to find out whatever>>>>
  • Macronutrients tend to be less available in soils with low pH.
    • Maleeha Habib
      Maleeha Habib on 19 Apr 10
       
      -Coffee has a lot of nitrogen -Coffee is acidic, meaning it has a high pH -When mixing coffee to the soil, the soil recieves has a high pH
  • Nitrogen (N) Nitrogen is a part of all living cells and is a necessary part of all proteins, enzymes and metabolic processes involved in the synthesis and transfer of energy. Nitrogen is a part of chlorophyll, the green pigment of the plant that is responsible for photosynthesis.  Helps plants with rapid growth, increasing seed and fruit production and improving the quality of leaf and forage crops.  Nitrogen often comes from fertilizer application and from the air (legumes get their N from the atmosphere, water or rainfall contributes very little nitrogen)
    • Maleeha Habib
      Maleeha Habib on 19 Apr 10
       
      Explains what nitrogen does
Maleeha Habib

Plant growth definition of Plant growth in the Free Online Encyclopedia. - 0 views

encyclopedia2.thefreedictionary.com/Plant+growth

shared by Maleeha Habib on 02 May 10 - Cached
  • Cell division in plants takes place in discrete zones called meristems.
    • Maleeha Habib
      Maleeha Habib on 02 May 10
       
      Apical Meristem: ---produce all the primary tissues of the stem and root Cylindrical Vascular Cambium: ---produce conducting cells while secondary thickening begins ---sheet of elongated cells which divde to produce xylem, water-conducting cells. and phloen, sugar-conducting cells Cell division in apical meristems increase length of stem and root. __________in vascular cambiums occur the stem and root have reached a fixed length. they then increase in girth (width) Cork Cambium: ---produce newer outer layers. these cells differentiate into the corky layers of the bark so that new protective layers are produced as the tree increases in circumference
  • Light is important in the control of plant growth. It drives the process of photosynthesis which produces the carbohydrates that are needed to osmotically retain water in the cell for growth.
  • An optimal temperature is needed for plant growth.
  • ...4 more annotations...
  • Prime among these are the water and nutrient supplies available in the soil.
  • Mineral nutrients are needed for the biochemical processes of the plant.
    • Maleeha Habib
      Maleeha Habib on 02 May 10
       
      All of my plants are getting minerals from the potting soil, but I am adding more nitrogen to four of my plants to see which will grow more
  • An irreversible increase in the size of the plant.
  • growth involves an increase in cell numbers by cell division and an increase in cell size
elizabeth helfant

Cell Structure and Functions - 0 views

www.tvdsb.on.ca/...cells.htm

shared by elizabeth helfant on 21 Apr 10 - Cached
  •    Endoplasmic Reticulum Vacuole                                                                Ribosomes Nucleus                                                                Golgi Apparatus
Maleeha Habib

Give your garden a jolt with coffee grounds - 0 views

www.seattlepi.com/...143052_lovejoy09.html

shared by Maleeha Habib on 19 Apr 10 - Cached
  • Ground coffee is high in nitrogen, making it a very good mulch for fast-growing vegetables. Many organic growers swear by coffee grounds as mulches for tomato plants, both for the nitrogen boost this heavy feeder appreciates and for coffee's ability to help suppress late blight.
    • Maleeha Habib
      Maleeha Habib on 19 Apr 10
       
      Nitrogen is very good for plant growth
  • My observation was confirmed by several soil scientists, who explained that coffee contains a number of substances that promote healthy plant growth.
  • Starbucks makes spent coffee grounds available year-round to its North America customers on a first-come, first-served basis. Grounds are packaged in reused coffee bags and come with simple directions for using the grounds in the garden
    • Maleeha Habib
      Maleeha Habib on 19 Apr 10
       
      I'll go to Starbucks to get my coffee grounds!
  • ...1 more annotation...
  • You also can rid areas of slugs and snails by mixing up some instant coffee
    • Maleeha Habib
      Maleeha Habib on 19 Apr 10
       
      coffee is used for many things in the garden!
Maleeha Habib

Coffee grounds- - 1 views

74.125.95.132/search

shared by Maleeha Habib on 17 Apr 10 - Cached
  • try using a thin layer (no more than half an inch) of coffee grounds and cover with a thicker (four inches) layer of coarse organic mulch like wood chips
    • Maleeha Habib
      Maleeha Habib on 17 Apr 10
       
      use a little amount of coffee and a lot of organic mulch like wood chips on top
  • carbon-to-nitrogen ratio of coffee grounds can be as low as 11:1, an ideal ratio for plant and soil nutrition.
    • Maleeha Habib
      Maleeha Habib on 17 Apr 10
       
      nitrogen is very important for plant growth
  • Many people use them as part of their compost pile, but increas- ing numbers of people are using them straight up as mulch, claiming they repel cats, kill slugs, prevent weeds, aerate and acidify the soil, provide nitrogen, attract earthworms … the list goes on.
  • ...1 more annotation...
  • Linda Chalker-Scott, Ph.D. MasterGardener WSU editor Extension Urban Horticulturist and Associate Professor, Puyallup Research and Extension Center, Washington State University Puyallup, Washington www.puyallup.wsu.edu/~Linda%20Chalker- Scot
    • Maleeha Habib
      Maleeha Habib on 17 Apr 10
       
      great for my TOECAP. she's very qualified!
Hayley Landman

Hydroponic Gardens | Plant roots, stems, and leaves - 1 views

www.hydroempire.com/...hydroponic-plant-parts.php

bio project

shared by Hayley Landman on 15 Apr 10 - Cached
  • the health of a plant can be easily seen in them. Leaves do not repair themselves, so the life of a plant can be read by its leaves
    • Hayley Landman
      Hayley Landman on 15 Apr 10
       
      A way to determine results?
  • Roots send nutrients (in exchange for sugar) up through leaf stems to the leaves for final processing. They are also large storage sites for excess energy from the leaves, which is stored as starch. The roots and their capacity to store starch will decide how well a plant will grow and how much the plant will yield.
  • Hayley Landman on 15 Apr 10
     
    possible site for research base
Ellis Brown

Does Music Affect Plant Growth? - 3 views

www.buzzle.com/...music-affect-plant-growth.html

music plant growth effect of music on plant growth

shared by Ellis Brown on 15 Apr 10 - Cached
  • there have been experiments which compel us to believe that music does affect plant growth
  • 'touch me not' which recoils and folds within itself at a slight touch.
  • They do have feelings and can sense
  • ...6 more annotations...
  • those exposed to soothing music grew better than the others. In one case, the plants had bent towards the music playing device! These plants were lush green with healthy stems.
  • does music affect plant growth? Well, yes
  • if there is a constant monotone that is being played, then it does not significantly affect plant growth
  • if it is mild, classical music, definite change of rate can be observed, in the growth of plants
  • It is a lengthy process, though. How music affects plant growth, cannot be observed within days of the plant being exposed to music. It takes weeks to identify the effects of music on plants.
    • Ellis Brown
      Ellis Brown on 15 Apr 10
       
      Could be a problem if not enough time is available...
  • After a while he observed that those plants had grown better than the other plants in the house, even though the regular watering was same for all.
Austin Kong

Plant Physiology Online: Symptoms of Deficiency In Essential Minerals - 2 views

4e.plantphys.net/article.php

shared by Austin Kong on 15 Apr 10 - Cached
  • a given individual visual symptom is seldom sufficient to make a definitive diagnosis of a plant’s nutrient status.
  • classic deficiency symptoms such as tip burn, chlorosis and necrosis are characteristically associated with more than one mineral deficiency and also with other stresses that by themselves are not diagnostic for any specific nutrient stress.
  • knowing the location and timing of these symptoms is a critical aspect of any nutrient status evaluation.
  • ...27 more annotations...
  • they respond to environmental changes as that affect nutrient availability.
  • Pathological symptoms can often be separated from nutritional symptoms by their distribution in a population of affected plants.
  • the stress is the result of pathology, the development of symptoms will have a tendency to vary between plants until a relatively advanced stage of the pathology is reached.
  • Plants remove substantial amounts of nutrients from the soil during their normal growth cycle and many long-term environmental changes occur as a result of this process. Effects on the soil go considerably beyond the straight removal or depletion of nutrients.
  • each nutrient has a number of different biological functions and each function may have an independent set of interactions with a wide range of environmental parameters.
  • Acute deficiency occurs when a nutrient is suddenly no longer available to a rapidly growing plant. Chronic deficiency occurs when there is a limited but continuous supply of a nutrient, at a rate that is insufficient to meet the growth demands of the plant.
  • Micronutrients are often present in the seed or as contaminants in the environment, so a plant of adequate size will exhaust these trace amounts of micronutrient and develop characteristic acute deficiency systems. When deficiency symptoms of macronutrients are sought, the macronutrient is removed suddenly from a suitable sized rapidly growing plant.
  • Because macronutrients are continuously required in relatively large amounts by rapidly growing plants, the available nutrients will be rapidly depleted, resulting in an acute deficiency.
  • the most common nutrient deficiency in natural environments is the case of a limited nutrient supply that is continuously renewed at a low rate from soil weathering processes. In such cases, the limited nutrient availability results in chronic nutrient deficiency symptoms.
  • interaction between nutrient mobility in the plant, and plant growth rate can be a major factor influencing the type and location of deficiency symptoms that develop.
  • very mobile nutrients such as nitrogen and potassium, deficiency symptoms develop predominantly in the older and mature leaves. This is a result of these nutrients being preferentially mobilized during times of nutrient stress from the older leaves to the newer leaves near the growing regions of the plant. Additionally, mobile nutrients newly acquired by the roots are also preferentially translocated to new leaves and the growing regions. Thus old and mature leaves are depleted of mobile nutrients during times of stress while the new leaves are maintained at a more favorable nutrient status.
  • The typical localization of deficiency symptoms of very weakly mobile nutrients such as calcium, boron, and iron is the opposite to that of the mobile nutrients; these deficiency symptoms are first displayed in the growing regions and new leaves while the old leaves remain in a favorable nutrient status. (This assume
  • s that these plants started with sufficient nutrient, but ran out of nutrient as they developed).
  • This type of development is likely to occur in the case of weakly mobile nutrients because excess nutrients in the older leaves will eventually be mobilized to supply newly developing tissues. In contrast, a plant with a similar supply that is growing rapidly will develop severe deficiencies in the actively growing tissue such as leaf edges and the growing region of the plant.
  • moderately mobile nutrients such as sulfur and magnesium are the limiting nutrients of the system, deficiency symptoms are normally seen over the entire plant. However the growth rate and rate of nutrient availability can make a considerable difference on the locations at which the symptoms develop. If the nutrient supply is marginal compared to the growth rate, symptoms will appear on the older tissue, but if the nutrient supply is very low compared to the growth rate, or the nutrient is totally depleted, the younger tissue will become deficient first.
  • symptoms are often the result of interactions with other environmental factors limiting the availability of the nutrient whose symptoms are expressed. T
  • Transition metals such as Cu, Zn Cr and Ni compete with Fe and each other for plant uptake.
  • specific to Fe and heavy metals but is true for all mineral nutrients that are chemically similar and have similar uptake mechanisms.
  • The toxicity of a low pH soil is another example of a basic nutrient deficiency. Low pH has a two-fold effect on soil nutrients: It enhances the leaching of cations, reducing their availability in the soil, and the relatively abundant protons in the soil compete with Ca and other cations for uptake. Thus, nutrient deficiencies can be induced by a number of different mechanisms often working in concert to limit the availability of a nutrient.
  • plants of similar species will often show significant differences in their nutrient use efficiency.
  • results from differences in growth rate, root distribution, phase of development, and efficiency of nutrient uptake and utilization. This implies that in any given location, plants from one species may become nutrient-deficient, while those from another species growing in the same environment right next to them, may not show any deficiency symptoms.
  • Growth rate also affects nutrient status. When the nutrient supply is barely inadequate for growth under existing environmental conditions, many plants adjust their growth rate to match that supported by the available nutrient supply without displaying typical visual deficiency symptoms.
  • rapid growth rate results in a high nutrient demand by these plants and a higher incidence of nutrient deficiency unless supplemental fertilizers are supplied.
  • agriculture systems chronic deficiency symptoms develop mostly in crops with little or limited fertilization.
  • all tissues of a plant are at the same nutrient status during times of stress. Leaves on the same plant that are exposed to different environmental conditions, (such as light), or those of different ages may have considerable differences in nutrient status. Mineral nutrients are for the most part acquired by the roots and translocated throughout the plant. The distance of any part of the plant to the roots will influence nutrient availability, particularly in the case of the less mobile nutrients. In plants recovering from nutrient deficiency, the root and conductive tissues recover first.
  • order to maintain rapid, optimal growth, all plant tissues must have a favorable nutrient status. Although a plant may be marginally low in a number of nutrients, only one nutrient at a time will limit overall growth. However, if the supply of that limiting nutrient is increased even slightly, the resulting increase in growth will increase the demand for all other nutrients and another nutrient, the next lowest in availability, will become limiting.
  • Because of their parallel veins, grasses and other monocots generally display the affects of chlorosis as a series of stripes rather than the netted interveinal chlorosis commonly found in dicots. The other major difference is that the marginal necrosis or chlorosis found in dicots is often expressed as tip burn in monocots.
julia olson

Soil Types and Testing - 0 views

www.rain.org/...soil-types-and-testing.htm

project

shared by julia olson on 14 Apr 10 - Cached
  • Soil can be described in many different ways, such as heavy, light, sandy, clay, loam, poor or good.
  • Although each of these factors is important, three factors (texture, organic content and pH) are more important than the others.
  • To be healthy, a soil needs to be able to breath and water needs to be able to move through it reasonably easily.
  • ...15 more annotations...
  • Sand doesn't hold many nutrients or water
  • Silt is a soil particle whose size is between sand and clay.
  • Soils high in clay content are called heavy soils.
  • Most of the water in a clay soil is so tightly bound to the clay particles that plants can't get it loose.
  • The amount if moisture found in soil varies greatly with the type of soil, climate and the amount of humus (organic material) in that soil.
  • The organic content of soil greatly influences the plant, animal and microorganism populations in that soil.
  • rainwater (if its not polluted) has a normal pH of about 6 - 6.5, which is slightly acidic.
  • It should then come as no surprise that most plants grow their best at around the same pH*.
  • Soil structure tells how the soil affects the movement of water, air and root penetration into the soil.
  • Soil temperature has a significant role in helping to determine the rate of plant growth, and whether a plant will even survive.
  • Sandy soil absorbs more than two inches of water per hour. It is very porous, with large spaces between soil particles.
  • Loam soil absorbs from .25 inches to 2 inches per hour.
  • Clay soil absorbs less than .25 inches of water per hour.
  • Sandy soil Loam soil, and Clay soil
  • It is a combination of sand and clay particles.
  • julia olson on 14 Apr 10
     
    plant soil
Cameron Jackson

How Does Color of Light Affect Plant Growth? | Garden Guides - 0 views

www.gardenguides.com/light-affect-plant-growth.html

shared by Cameron Jackson on 15 Apr 10 - Cached
  • he color of light is a major consideration when you grow plants indoors. Fluorescent light that contains lots of blue light is good for starting seeds indoors
    • Cameron Jackson
      Cameron Jackson on 15 Apr 10
       
      Consider using fluorescent light in experiment as the "blue light" 
Beth Ignatova

AccessScience | Encyclopedia Article | Soil fertility - 2 views

www.accessscience.com/content.aspx

shared by Beth Ignatova on 09 Apr 10 - Cached
  • Sixteen chemical elements are required for the growth of all plants: carbon, oxygen, and hydrogen (these three are obtained from carbon dioxide and water), plus nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, molybdenum, and chlorine. Some plant species also require one or more of the elements cobalt, sodium, vanadium, and silicon.
  • 13 essential mineral nutrien
  • J. R. Brown (ed.), Recommended Chemical Soil Test Procedures for the North Central Region, Missouri Agricultural Experiment Station, Columbia, 1998
  • ...1 more annotation...
  • dissolution
    • Beth Ignatova
      Beth Ignatova on 12 Apr 10
       
      Dissolution (chemistry), or solvation, in chemistry, the process of dissolving a solid substance into a solvent to yield a solution (From Wikipedia and this was Hayley's idea)
  • Laura Bradford on 09 Apr 10
     
    Soil Fertility: How is this important to growth of a plant?
  • Laura Bradford on 09 Apr 10
     
    Note the Bibliography. I've highlighted an article, available as a pdf file, with information on interesting experimental procedures for how to handle and test soil. Might be helpful for your experimental design.
Sarah Tolch

AccessScience | Research Update | Phototropin - 5 views

www.accessscience.com/content.aspx

shared by Sarah Tolch on 09 Apr 10 - Cached
  • Typically, stems show positive phototropism (movement toward the light), whereas roots exhibit negative phototropic movement (away from the source of light).
  • Arabidopsis contains two phototropins referred to as phot1 and phot2. Mutants of Arabidopsis lacking both phototropins lose their phototropic responsiveness
  • Phototropic response
  • ...10 more annotations...
  • phototropins control the movement of chloroplasts
  • these responses serve to enhance the photosynthetic
  • a small fraction of the receptor pool is rapidly internalized (within minutes) upon blue light irradiation
  • Phototropins, like photoreceptor pigments associated with mammalian vision, comprise many amino acids (900–1000) that form the main structure of the protein (the apoprotein) to which an accessory chemical cofactor is bound that can absorb light and impart color (the chromophore)
  • Phototropins are typically associated with the plasma membrane
  • However, the biological significance
  • As light passes through the stem, it becomes progressively diffracted, thereby generating a gradient of phototropin activation across the organ, with the highest level of activity occurring on the irradiated side
  • In some plant species, including the fern Adiantum capillus-veneris, phototropism and chloroplast movement are induced by red light as well as blue.
  • novel
  • The presence of such a hybrid photoreceptor is proposed to enhance light sensitivity and aid the prevalence of species such as ferns in low light conditions
Judi Crouch

Hypoxia in the Northern Gulf of Mexico - 4 views

www.gulfhypoxia.net/Overview

Crouch

shared by Judi Crouch on 12 Apr 10 - Cached
  • Hypoxia, or oxygen depletion, is an environmental phenomenon where the concentration of dissolved oxygen in the water column decreases to a level that can no longer support living aquatic organisms.
  • Hypoxic and anoxic (no oxygen) waters have existed throughout geologic time, but their occurrence in shallow coastal and estuarine areas appears to be increasing as a result of human activities (Diaz and Rosenberg, 1995). The largest hypoxic zone currently affecting the United States, and the second largest hypoxic zone worldwide, occurs in the northern Gulf of Mexico adjacent to the Mississippi River on the Louisiana/Texas continental shelf.
  • What causes hypoxia? Major events leading to the formation of hypoxia in the Gulf of Mexico include: Freshwater discharge and nutrient loading of the Mississippi River Nutrient-enhanced primary production, or eutrophication Decomposition of biomass by bacteria on the ocean floor Depletion of oxygen due to stratification
  • ...5 more annotations...
  • Mississippi River nutrient concentrations and loading to the adjacent continental shelf have greatly changed in the last half of the 20th century. During this time there has been a marked increase in the concentration of nitrogen and phosphorous in the Lower Mississippi River. This increase has been attributed to the increased use of nitrogen and phosphorous fertilizers,
  • Eutrophication
  • eutrophication initiates a massive growth of phytoplankton on the water’s surface.
  • This stratification leaves the bottom layer isolated from the surface layer and cut off from a normal resupply of oxygen from the atmosphere.
  • Hypoxia was first documented in the northern Gulf of Mexico off the Louisiana coast in 1972.
  • Judi Crouch on 12 Apr 10
     
    Good intro to the concept of "dead zones" (hypoxia)
  • Judi Crouch on 12 Apr 10
     
    This is a good introduction to the concept of a "dead zone."
  • Judi Crouch on 12 Apr 10
     
    What does anthropogenically mean?
bacoco coco

Essential Plant Nutrients - 2 views

www.cartage.org.lb/...EssentialPlant.htm

Plant nutrients

shared by bacoco coco on 09 Apr 10 - Cached
  • Essential plant nutrients: their relative amounts in plants, functions and classification
    • bacoco coco
      bacoco coco on 09 Apr 10
       
      This table may be helpful in determining a topic for an experiment. You would only want to choose one nutrient with which to run an experiment.
  • Five types of deficiency or toxicity symptoms are observed:
    • bacoco coco
      bacoco coco on 09 Apr 10
       
      Here are the visible signs if the soil does not have enough of or too much of a nutrient.
    • bacoco coco
      bacoco coco on 09 Apr 10
       
      Plants can be damaged is there is too much of one nutrient (toxicity) or not enough of a nutrient (deficiency).
  • ...2 more annotations...
    • bacoco coco
      bacoco coco on 09 Apr 10
       
      Nutrients (in the soid) are needed either in large amounts (macronutrients), medium amounts (micronutrients), or in trace amounts
  • Table 2. Generalized Symptoms of Plant Nutrient Deficiency or Excess
Pascale Michelon

Plant hormone and growth regulators - 2 views

extension.oregonstate.edu/...hormones.html

plant hormones

shared by Pascale Michelon on 11 Apr 10 - Cached
  • (Table 5)
  • Hormones are produced naturally by plants, while plant growth regulators are applied to plants by humans
    • Pascale Michelon
      Pascale Michelon on 11 Apr 10
       
      This is interesting because it shows you that if you want to manipulate hormones in an experiment you can use plant growth regulators to mimic the action of hormones.
  • ...3 more annotations...
  • There are five groups of plant-growth-regulating compounds: auxin, gibberellin (GA), cytokinin, ethylene, and abscisic acid (ABA).
  • Ethylene is unique in that it is found only in the gaseous form. It
  • induces ripening, causes leaves to droop (epinasty) and drop (abscission), and promotes senescence.
    • Pascale Michelon
      Pascale Michelon on 11 Apr 10
       
      The effects of ethylene (promotion of both aging/death and ripening) may explain why just one bad apple in a basket may spoil the whole bunch.
  • Pascale Michelon on 11 Apr 10
     
    Plant hormones and growth regulators are chemicals that affect flowering; aging; root growth; killing of leaves; prevention or promotion of stem elongation; color enhancement of fruit; prevention of leafing and/or leaf fall; etc.
elizabeth helfant

http://bonzobox.com/out/?u=http://www.paessp.org/documents/conference/2008_McTighe_slid... - 2 views

docs.google.com/viewer

differentiation

shared by elizabeth helfant on 05 Apr 10 - No Cached
    • elizabeth helfant
      elizabeth helfant on 05 Apr 10
       
      What unit do you really march through content in?
elizabeth helfant

State of the Union speech unlikely to ease worries, analysts say - CNN.com - 0 views

www.cnn.com/...index.html

shared by elizabeth helfant on 27 Jan 10 - Cached
  • Frum said Obama's new populist tone, which he said emerged after the Democrats' surprising loss in the
    • elizabeth helfant
      elizabeth helfant on 27 Jan 10
       
      Is this a violation 1st
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