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Elicitors
In plant biology, elicitors are extrinsic or foreign molecules often associated with plant pests, diseases or synergistic organisms. Elicitor molecules can attach to special receptor proteins located on plant cell membranes. These receptors are able to recognize the molecular pattern of elicitors and trigger intracellular defence signalling via the octadecanoid pathway. This response results in the enhanced synthesis of metabolites which reduce damage and increase resistance to pest, disease or environmental stress. This is an immune response called pattern triggered immunity (PTI). PTI is effective against necrotrophic microorganisms. An example is chitosan which is found in insects, fungi and the shells of crustaceans. Chitosan is used in agriculture as a natural biocontrol agent, to improve plant health and increase crop yields. Effectors and hormones Effectors and hormones are other signalling molecules often confused with elicitors. Elicitors and effectors differ fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chitosan
Chitosan is a linear polysaccharide composed of randomly distributed β-(1→4)-linked D-glucosamine (deacetylated unit) and ''N''-acetyl-D-glucosamine (acetylated unit). It is made by treating the chitin shells of shrimp and other crustaceans with an alkaline substance, such as sodium hydroxide. Chitosan has a number of commercial and possible biomedical uses. It can be used in agriculture as a seed treatment and biopesticide, helping plants to fight off fungal infections. In winemaking, it can be used as a fining agent, also helping to prevent spoilage. In industry, it can be used in a self-healing polyurethane paint coating. In medicine, it is useful in bandages to reduce bleeding and as an antibacterial agent; it can also be used to help deliver drugs through the skin. History In 1799, British chemist Charles Hatchett experimented with decalcifying the shells of various crustaceans, finding that a soft, yellow and cartilage-like substance was left behind that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Biology
Botany, also called plant science, is the branch of natural science Natural science or empirical science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer ... and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who specialises in this field. "Plant" and "botany" may be defined more narrowly to include only land plants and their study, which is also known as phytology. Phytologists or botanists (in the strict sense) study approximately 410,000 species of Embryophyte, land plants, including some 391,000 species of vascular plants (of which approximately 369,000 are flowering plants) and approximately 20,000 bryophytes. Botany originated as history of herbalism#Prehistory, prehistoric herbalism to identif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octadecanoid Pathway
The octadecanoid pathway is a biosynthesis, biosynthetic pathway for the production of the phytohormone jasmonic acid (JA), an important hormone for induction of defense genes. JA is synthesized from alpha-linolenic acid, which can be released from the plasma membrane by certain lipase enzymes. For example, in the wound defense response, phospholipase C will cause the release of alpha-linolenic acid for JA synthesis. In the first step, alpha-linolenic acid is redox, oxidized by the enzyme lipoxygenase. This forms 13-hydroperoxylinolenic acid, which is then modified by a dehydrase and undergoes cyclization by allene oxide cyclase to form 12-oxo-phytodienoic acid. This undergoes reduction and three rounds of beta oxidation to form jasmonic acid. Footnotes References * * Metabolic pathways {{biochem-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pattern Triggered Immunity
A pattern is a regularity in the world, in human-made design, or in abstract ideas. As such, the elements of a pattern repeat in a predictable manner. A geometric pattern is a kind of pattern formed of geometric shapes and typically repeated like a wallpaper design. Any of the senses may directly observe patterns. Conversely, abstract patterns in science, mathematics, or language may be observable only by analysis. Direct observation in practice means seeing visual patterns, which are widespread in nature and in art. Visual patterns in nature are often chaotic, rarely exactly repeating, and often involve fractals. Natural patterns include spirals, meanders, waves, foams, tessellation, tilings, fracture, cracks, and those created by Symmetry, symmetries of rotation symmetry, rotation and reflection symmetry, reflection. Patterns have an underlying Mathematics, mathematical structure; indeed, mathematics can be seen as the search for regularities, and the output of any function is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Necrotrophic
A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as one of the traditional eukaryotic kingdoms, along with Animalia, Plantae, and either Protista or Protozoa and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''true fungi'' or ''Eumycete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Hormone
Plant hormones (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, including embryogenesis, the regulation of Organ (anatomy), organ size, pathogen defense, Stress (biology), stress tolerance and Reproduction, reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Frits Warmolt Went, Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in vascular plant, vascular plants ("higher plants"). Some phytohormones also occur in microorganisms, such as unicellular fungus, fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites. Characteristi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
