"As the mycelia develop, no further water is added, thereby allowing the substratum to dry, preferably to a substratum moisture content of below about 75%. Drying of the substratum prior to feeding is considered to be an important factor in inhibiting growth of bacteria and other fungi which would harm or compete with the developing morels."
"It is desirable that as much sclerotia be produced within the substratum as is possible during this stage because there appears to be a direct relationship between the amount of sclerotia in the substratum and the total weight of ascocarps that develop per unit area of the substratum."
"During feeding, the soil moisture is maintained at a level of between about 45% and about 70%, the relative humidity is maintained at between about 85% and about 95% and the temperature is maintained between about 10°C. and about 22°C. Feeding continues for a period of between about 7 and about 40 days, typically about 16 days. At the end of the feeding period, both conidia and sclerotia may be observed in substantial numbers on the surface of the substratum."
Abscisic acid, or dormin, is a plant HORMONE that promotes abscission, the process responsible for the fall of leaves, flowers, and fruits. It is
produced in response to such stimuli as the changing relative lengths of day and night during autumn.
It shouldn't be confused with ascorbic acid.
The morels pick up on this chemical when trees are under heat stress or drought, and of course they are connected to the tree roots.
Probably a temperature around 96°F or 98°F.
Tree roots produce abscisic acid during those times of heat stress or other types of stress, i.e. water, injury.
Its sent to the leaves during those times, but in the fall the excess is sent back down to the roots.
Another thing to note is the possibility that those small morels found in the woodland interior are the direct result of small sapling trees (That have been robbed of water by the much larger adult trees. These little trees only produce so much abscisic acid and sometimes are stressed out by the much larger trees stealing the water from them.) Or adult trees that don't produce the chemical in large amounts.
Abscisic acid is an isoprenoid which makes it structurally related to isoprene.
Isoprene is the basic building block of natural rubber.
Abscisic acid is a plant hormone that inhibits cell division and stimulates the
retention of water.
Abscisic acid is a plant hormone that promotes dormancy.
Abscisic acid biologically is derived from carotenes which are plant pigments.
Abscisic acid is nullified by auxins and gibberellins.
Abscisic acid is leached from roots and seeds by excess water.
The one thing to keep in mind though is that it is similar to rubber!
Also keep in mind that abscisic acid is used to PREVENT FRUIT FROM RIPENING
Another example is the Elm tree which can not get its sap up the trunk due to
the parasitic fungi Dutch Elm's Disease that is killing it which causes it to drop leaves.
Dutch elm disease affects the fluid-transport, or vascular system of elm trees. It is caused by the fungus Ceratocystis ulmi.
When the beetles emerge and feed on young twigs of healthy elms, they introduce the fungus, which then multiplies in the vascular system, causing leaf yellowing, defoliation, and rapid death of the tree.
Glycoside compounds are a large family of plant chemicals composed of a sugar bonded to a nonsugar component, called a glycon, through a hydroxyl (OH) group. The sugar generally is glucose. Their properties--crystalline solids, bitter taste, and limited solubility in water--and chemical makeup have led botanists to postulate that plants may use glycosides to store harmful substances. This hypothesis has been supported by the observation of a chemical, 2-chloroethanol, that breaks the dormancy of tubers. Plant tissue converts the chemical to a glycoside. The reverse process, hydrolysis, can be accomplished in the laboratory with aqueous acid or in the plant with enzymes.
Other possible functions of the glycoside in plants are movement of harmful material to tissues where it can eventually be shed (for example, bark, fruit rinds, or seed coats) and movement of decorative materials, such as pigment, from the leaves to the flowers or fruits. Still, the detoxication thesis is important and is also supported by evidence from animals. The urine of a dog fed hydroquinone will subsequently contain a compound related to the glycosides.
Long before anything was known about their chemistry, glycosides were used as natural dyes, drugs, and condiments. MADDER, an ancient vegetable dye, was the first glycoside whose chemical structure was determined. After hydrolysis, the plant's root yields glucose, xylose, and alizarin, which, in combination with certain metallic salts or mordant, produces colors. Madder root has been replaced by a synthetic product. Willow bark, which contains an aglycon related to aspirin, was used to treat fever and acute rheumatism. Mustard seeds contain a glycoside, sinigrin, in which the glucose is connected to the aglycon through a sulfur rather than an oxygen atom.
K. Thomas Finley
(abscisic acid + glucose) = glycoside?
Below I've gathered some notes in an attempt to map out the metabolic pathways that the mycelial morel fungus would take in chemical assimilation and conversions.
In addition to being readily oxidized to form organic acids and reduced to form alcohols, aldehydes can also undergo polymerization. The first commercially successful synthetic resin, BAKELITE, for example, is a polymerization product of formaldehyde and phenol, and Formica derives from formaldehyde and urea. Aldehydes are used as intermediates in the production of resins, dyes, pharmaceuticals, and other products, and are employed as solvents and perfume ingredients. Biologically, various sugars and hormones found in the body contain the aldehyde structure.
Isoprene is a five-carbon conjugated diene; it is of industrial importance because it is the basic chemical unit of natural rubber. Thus it is the major ingredient used to make certain types of synthetic RUBBER and other elastomers. Isoprene does not occur in nature in monomeric form but is widespread in TERPENES. Common terpenes include phytol, menthol, the carotenoids (vitamin A), and the sterols (cholesterol).
Dienes, also called alkadienes, are a class of organic compounds that have two sets of carbon-carbon double bonds. When the double bonds are separated by one or more CH2 groups, the bonds are said to be isolated, and the properties of their compounds are similar to those of simple ALKENES. Different and interesting behavior is shown, however, by dienes possessing cumulated and conjugated double bonds:
Categories: Plant hormones | Carboxylic acids | Sesquiterpenes | Alcohols | Ketones | Apocarotenoids
Apocarotenoids = apo (formed from; related to) carotenoids
Could also be Apoisoprenoid but isoprenoid is the same thing
Abscisic acid is a ketone that can form a glycoside with glucose that is a ketose, which effectively makes it a polymer of an isoprenoid and making a natural rubber derivative.
Effectively it is a polymer that is similar to a polysaccharide.
But can ketones undergo polymerization?
Yes they can!
Methyl isobutyl ketone is used as a solvent for paints and lacquers. Polymerization of methyl methacrylate using peroxide initiators gives a strong, highly transparent, thermoplastic solid polymer that is sold under such trade names as Lucite and Plexiglas.
An alkene is any of a group of organic compounds that contain a carbon-carbon double bond. The molecules of alkenes are composed only of carbon and hydrogen atoms but contain less hydrogen per carbon atom than the ALKANES, or paraffins, to which they can be converted by the addition of hydrogen. The alkenes (often called olefins) are thus unsaturated hydrocarbons.
Ethene or ethylene is the simplest member of the series. Systematic names for alkenes are derived by appending the suffix ene to the root name for the alkane with the same carbon content. Whereas carbon-carbon single bonds permit rotation of the atoms or groups of atoms linked to the carbons, double bonds between two atoms completely restrict rotation about the double bond. As a result 2-butene can exist in two different configurations of its atoms, called geometric isomers; the two forms are cis-2-butene and trans-2-butene. These isomers possess the same number of atoms but have different structures and different physical properties.
Alkene hydrocarbons are much more chemically reactive than the alkanes because the double bond is more susceptible to attack by other reagents. The double bond can readily be oxidized or reduced, and a wide variety of reagents can be added to the alkene molecule at the double-bond site.
Ethylene, propylene, and related compounds are leading organic raw materials in the chemistry industry; they are used in the production of many other compounds, including various polymers. Butene (butylene) has played an important role in the rubber industry, but heavier alkenes are commercially insignificant.
Polymerization is a reaction in which small molecules react to form large molecules, called polymers, that contain many repeating units (poly = many, mer = units). Polymers find wide use as plastics, finishes, and fibers. For a molecule (called a monomer) to form a polymer, it must have at least two reactive sites; that is, it must be difunctional.
Condensation Polymerization
An example of a difunctional molecule is hydroxy acid. The hydroxyl (OH) group of one hydroxy acid monomer reacts with the carboxyl group (COOH) of another hydroxy acid monomer to form an ester (a dimer). The ester dimer is also difunctional and may react further to form a polyester, where n is the number of repeating units in the polymer chain. Polyesters may also be formed by reacting a dihydric alcohol (glycol) with a dicarboxylic acid.
The production of Dacron is an example of reaction (2) in which ethylene glycol is the dialcohol and terephthalic acid is the dicarboxylic acid. The above reactions are condensation reactions because a smaller molecule is split off, and the polymers are called condensation polymers. Another important class of condensation polymers is the polyamides, which are produced by the reaction of AMINO ACIDS or by the reaction of a diamine with a dicarboxylic acid. The product of the amino acid reaction is polyalanine, the protein in wild silk, and the product of the reaction of a diamine with a dicarboxylic acid is Nylon 66, a commercial fiber.
Polymers have useful mechanical properties only if they are of sufficiently high molecular weight. Only four condensation reactions give sufficiently high yields to ensure reliably high-molecular-weight polymers: (a) esterification by ester interchange, (b) esterification and amidation by the Schotten-Baumann reaction of acyl chlorides, (c) amidation by thermal dehydration of ammonium salts, and (d) formation of urethanes from isocyanates and alcohols, and ureas from isocyanates and amines.
Addition Polymerization
In an addition polymerization the product molecule contains all the atoms that were present in the reactant monomer. The resulting polymer is called an addition polymer. Alkenes are difunctional, so they also react to form polymers by addition. In the latter reaction, ethylene reacts in the presence of a suitable catalyst--free radicals, acids, or bases--to form polyethylene (see CHAIN REACTION, CHEMICAL). Other alkenes also yield important addition polymers such as polyacrylonitrile, or Orlon, and poly(methyl methacrylate), marketed under the trade names Lucite, Plexiglas, and Perspex. Other important addition polymers are polyvinyl chloride, and Teflon (polytetrafluoroethylene).
Acetone, or 2-propanone, or dimethylketone, is a fragrant, colorless, and flammable liquid that boils at 56.2°C and solidifies at -34.8°C. Acetone is mainly produced by the dehydrogenation of isopropyl alcohol, which is obtained from propylene. Small amounts of acetone are present in blood and urine, but some diabetic patients show larger than normal concentrations. Diabetics evacuate this excess in urine (acetonuria) and through their lungs; its presence in the exhaled air causes an odor known as "acetone breath." In industry, acetone is an important solvent for cellulose nitrate and cellulose acetate and is also used in the production of explosives.
Abscisic acid
Abscisic acid (ABA), also known as abscisin II and dormin, is a plant hormone. ABA functions in many plant developmental processes, including bud dormancy; it is degraded by the enzyme, (+)-abscisic acid 8'-hydroxylase.
Function
ABA was originally believed to be involved in abscission - this is now known only to be the case in a small number of plants. ABA-mediated signalling also plays an important part in plant responses to environmental stress and plant pathogens.[2][3] The plant genes for ABA biosynthesis and sequence of the pathway have been elucidated.[4][5] ABA is also produced by some plant pathogenic fungi via a biosynthetic route different from ABA biosynthesis in plants.[6]
Abscisic acid owes its names to its role in the abscission of plant leaves. In preparation for winter, ABA is produced in terminal buds.[citation needed] This slows plant growth and directs leaf primordia to develop scales to protect the dormant buds during the cold season. ABA also inhibits the division of cells in the vascular cambium, adjusting to cold conditions in the winter by suspending primary and secondary growth.
Abscisic acid is also produced in the roots in response to decreased soil water potential and other situations in which the plant may be under stress. ABA then translocates to the leaves, where it rapidly alters the osmotic potential of stomatal guard cells, causing them to shrink and stomata to close. The ABA-induced stomatal closure reduces transpiration, thus preventing further water loss from the leaves in times of low water availability.
Seed germination is inhibited by ABA in antagonism with gibberellin. ABA also prevents loss of seed dormancy.
Several ABA mutant Arabidopsis thaliana plants have been identified both those deficient in ABA production and those with altered sensitivity to its action. Plants that are hypersensitive or insensitive to ABA show phenotypes in seed dormancy, germination, stomatal regulation, and some mutants show stunted growth and brown/yellow leaves.[7] These mutants reflect the importance of ABA in seed germination and early embryo development.
Pyrabactin (a pyridyl containing ABA activator) is a naphthalene sulfonamide hypocotyl cell expansion inhibitor, which is an agonist of the seed ABA signaling pathway.[citation needed] It is the first agonist of the ABA pathway that is not structurally related to ABA.[citation needed]
Biosynthesis
Abscisic acid (ABA) is an isoprenoid plant hormone, which is synthesized in the plastidal 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway; unlike the structurally related sesquiterpenes, which are formed from the mevalonic acid-derived precursor farnesyl diphosphate (FDP), the C15 backbone of ABA is formed after cleavage of C40 carotenoids in MEP. Zeaxanthin is the first committed ABA precursor; a series of enzyme-catalyzed epoxidations and isomerizations via violaxanthin, and final cleavage of the C40 carotenoid by a dioxygenation reaction yields the proximal ABA precursor, xanthoxin, which is then further oxidized to ABA.[4]
Abamine has been designed, synthesized, developed and then patented as the first specific ABA biosynthesis inhibitor, which makes it possible to regulate endogenous level of ABA. [8]
The biological significance of the C-terminal methylester and the farnesyl group of a-factor has been tested with synthetic peptides in which these groups have been replaced by other substituents (Marcus et al., 1991). Removal of the farnesyl or methyl group resulted in significant reduction but not complete loss of activity. The farnesyl group could be replaced by other hydrophobic side chains, resulting in pheromones that were equally active or even more active than wild-type a-factor (Marcus et al., 1991)
- Sexual Pheromones and Mating Responses in Fungi
Michael Bolker and Regine Kahmann
Location and timing of ABA biosynthesis
(SO ABSICISIC ACID IS NECESSARY FOR FUNGAL SEXUAL PHEROMONES)
Released during desiccation of the vegetative tissues and when roots encounter soil compaction.[9]
Synthesized in green fruits at the beginning of the winter period
Synthesized in maturing seeds, establishing dormancy
Mobile within the leaf and can be rapidly translocated from the roots to the leaves by the transpiration stream in the xylem
Produced in response to environmental stress, such as heat stress, water stress, salt stress
Synthesized in all plant parts, e.g., roots, flowers, leaves and stems
Effects
Antitranspirant - Induces stomatal closure, decreasing transpiration to prevent water loss.[10]
Inhibits fruit ripening
Responsible for seed dormancy by inhibiting cell growth inhibits seed germination
Inhibits the synthesis of Kinetin nucleotide [11]
Downregulates enzymes needed for photosynthesis.[12]
References
Abscisic Acid Chemical Name
Zhu JK. (2002). "Salt and drought stress signal transduction in plants". Annu Rev Plant Biol. 53: 247273. doi:10.1146/annurev.arplant.53.091401.143329. PMID 12221975.
Seo M, Koshiba T (2002). "Complex regulation of ABA biosynthesis in plants". Trends Plant Sci. 7 (1): 4148. doi:10.1016/S1360-1385(01)02187-2. PMID 11804826.
a b Nambara E, Marion-Poll A. (2005). "Abscisic acid biosynthesis and catabolism". Annu Rev Plant Biol. 56: 165185. doi:10.1146/annurev.arplant.56.032604.144046. PMID 15862093.
Milborrow BV (2001). "The pathway of biosynthesis of abscisic acid in vascular plants: a review of the present state of knowledge of ABA biosynthesis". J Exp Bot. 52 (359): 11451164. doi:10.1093/jexbot/52.359.1145. PMID 11432933.
Siewers V, Smedsgaard J, Tudzynski P. (2004). "The P450 monooxygenase BcABA1 is essential for abscisic acid biosynthesis in Botrytis cinerea". Appl Environ. Microbiol. 70 (7): 38683876. doi:10.1128/AEM.70.7.3868-3876.2004. PMC 444755. PMID 15240257. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=444755.
NASC - Arabidopsis Stock Centre
http://www.google.com.au/patents?id=BnN6AAAAEBAJ
DeJong-Hughes, J., et al. (2001) Soil Compaction: causes, effects and control. University of Minnesota extension service
Zhang, J., U. Schurr, and W.J. Davies, Control of Stomatal Behaviour by Abscisic Acid which Apparently Originates in the Roots. Journal of Experimental Botany, 1987. 38(7): p. 1174.
J. A. MIERNYK, Abscisic Acid Inhibition of Kinetin Nucleotide Formation in Germinating Lettuce Seeds. Physiologia Plantarum, 45 '1': p. 63 - 66.
P M Chandler, and M Robertson, GENE EXPRESSION REGULATED BY ABSCISIC ACID AND ITS RELATION TO STRESS TOLERANCE. Annu. Rev. Plant Physiol. Plant Mol. Biol, 1994. 45: p. 113-141. v · d · ePlant hormones
Abscisic acid Auxins Cytokinins Ethylene Gibberellins
Brassinosteroids Florigen Jasmonates Karrikins Plant peptide hormones Polyamine Salicylic acid Strigolactones
Categories: Plant hormones | Carboxylic acids | Sesquiterpenes | Alcohols | Ketones | Apocarotenoids
Abscisic acid
Melting point
186-188 °C, 459-461 K, 367-370 °F
Boiling point
120 °C, 393 K, 248 °F (sublimes)
Cytokinin is an isoprenoid!
---------------------------
There are two types of cytokinins: adenine-type cytokinins represented by kinetin, zeatin and 6-benzylaminopurine.
The majority of adenine-type cytokinins are synthesized in the roots.
Adenosine phosphate-isopentenyltransferase (IPT) catalyses the first reaction in the biosynthesis of isoprene cytokinins. It may use ATP, ADP or
AMP as substrates and may use dimethylallyl diphosphate (DMAPP) or hydroxymethylbutenyl diphosphate (HMBDP) as prenyl donors.[8] This
reaction is the rate limiting step in cytokinin biosynthesis. DMAPP and HMBDP used in cytokinin biosynthesis are produced by the
methylerythritol phosphate pathway (MEP).[8]
Kinetin is the most important agent from the cytokinin group. Many experiments were done by the scientists on the effect of Cytokinin on plant
physiology. As mentioned above, it increases the cell division, have effects on the initiation and development of root, helps in breaking bud
dormancy.
--------------------------------
Gibberillic Acid
-----------------------------
Gibberellins are produced in greater mass when the plant is exposed to cold temperatures. They stimulate cell elongation, breaking and budding,
seedless fruits, and seed germination. They do the last by breaking the seed's dormancy and acting as a chemical messenger. Its hormone
binds to a receptor, and Ca2+ activates a protein, calmodulin, and the complex binds to DNA, producing an enzyme to stimulate growth in the
embryo.
--------------------------------
Stearic acid is used to combine rubber with other substances, such as pigments, or materials that control the flexibility of rubber products; it is also
used in the polymerization of styrene and butadiene in making artificial rubber
--------------------
If you wanna ride, don't ride the white horse, if you wanna ride, ride the white pony
Edited by AcidHorse (11/22/14 12:52 PM)
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