Phloem: Plant tissue that carries nutrients, especially sucrose, by turgor pressure. Movement is bidirectional, in contrast to XYLEM where it is only upward. Phloem originates and grows outwards from meristematic cells (MERISTEM) in the vascular cambium. P-proteins, a type of LECTINS, are characteristically found in phloem.Xylem: Plant tissue that carries water up the root and stem. Xylem cell walls derive most of their strength from LIGNIN. The vessels are similar to PHLOEM sieve tubes but lack companion cells and do not have perforated sides and pores.Plant Stems: Parts of plants that usually grow vertically upwards towards the light and support the leaves, buds, and reproductive structures. (From Concise Dictionary of Biology, 1990)Plant Structures: The parts of plants, including SEEDS.Plant Exudates: Substances released by PLANTS such as PLANT GUMS and PLANT RESINS.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Cucurbita: A plant genus of the family CUCURBITACEAE, order Violales, subclass Dilleniidae, which includes pumpkin, gourd and squash.Cambium: A layer of living cells between the bark and hardwood that each year produces additional wood and bark cells, forming concentric growth rings.Plant Transpiration: The loss of water vapor by plants to the atmosphere. It occurs mainly from the leaves through pores (stomata) whose primary function is gas exchange. The water is replaced by a continuous column of water moving upwards from the roots within the xylem vessels. (Concise Dictionary of Biology, 1990)Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)Wood: A product of hard secondary xylem composed of CELLULOSE, hemicellulose, and LIGNANS, that is under the bark of trees and shrubs. It is used in construction and as a source of CHARCOAL and many other products.Populus: A plant genus of the family SALICACEAE. Balm of Gilead is a common name used for P. candicans, or P. gileadensis, or P. jackii, and sometimes also used for ABIES BALSAMEA or for COMMIPHORA.Plant Shoots: New immature growth of a plant including stem, leaves, tips of branches, and SEEDLINGS.Cucurbitaceae: The gourd plant family of the order Violales, subclass Dilleniidae, class Magnoliopsida. It is sometimes placed in its own order, Cucurbitales. 'Melon' generally refers to CUCUMIS; CITRULLUS; or MOMORDICA.Cucumis sativus: A creeping annual plant species of the CUCURBITACEAE family. It has a rough succulent, trailing stem and hairy leaves with three to five pointed lobes.Apium graveolens: A plant species of the family APIACEAE. The stalks are a food source.Plant Vascular Bundle: A strand of primary conductive plant tissue consisting essentially of XYLEM, PHLOEM, and CAMBIUM.Plasmodesmata: Membrane-like channels of cytoplasm connecting adjacent plant cells. Plasmodesmata connect through pores in the CELL WALL and associate with the CYTOSKELETON machinery. They are essential for intercellular transport and communication.Scrophulariaceae: The figwort plant family of the order Lamiales. The family is characterized by bisexual flowers with tubular corollas (fused petals) that are bilaterally symmetrical (two-lips) and have four stamens in most, two of which are usually shorter.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.Aphids: A family (Aphididae) of small insects, in the suborder Sternorrhyncha, that suck the juices of plants. Important genera include Schizaphis and Myzus. The latter is known to carry more than 100 virus diseases between plants.Lignin: The most abundant natural aromatic organic polymer found in all vascular plants. Lignin together with cellulose and hemicellulose are the major cell wall components of the fibers of all wood and grass species. Lignin is composed of coniferyl, p-coumaryl, and sinapyl alcohols in varying ratios in different plant species. (From Merck Index, 11th ed)Picea: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are evergreen, pyramidal trees with whorled branches and thin, scaly bark. Each of the linear, spirally arranged leaves is jointed near the stem on a separate woody base.Biological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Ricinus: A plant genus of the family EUPHORBIACEAE, order Euphorbiales, subclass Rosidae. The seed of Ricinus communis L. is the CASTOR BEAN which is the source of CASTOR OIL; RICIN; and other lectins.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.Carbohydrate Metabolism: Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.Sucrose: A nonreducing disaccharide composed of GLUCOSE and FRUCTOSE linked via their anomeric carbons. It is obtained commercially from SUGARCANE, sugar beet (BETA VULGARIS), and other plants and used extensively as a food and a sweetener.Trees: Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.Xylella: A genus of gram-negative, aerobic bacteria, in the family XANTHOMONADACEAE. It is found in the xylem of plant tissue.Pinus: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are evergreen trees mainly in temperate climates.Plant Diseases: Diseases of plants.Acer: A plant genus of the family ACERACEAE, best known for trees with palmately lobed leaves.Coniferophyta: A plant division of GYMNOSPERMS consisting of cone-bearing trees and shrubs.Vitis: A plant genus in the family VITACEAE, order Rhamnales, subclass Rosidae. It is a woody vine cultivated worldwide. It is best known for grapes, the edible fruit and used to make WINE and raisins.Plantago: A plant genus of the family Plantaginaceae. The small plants usually have a dense tuft of basal leaves and long, leafless stalks bearing a terminal spike of small flowers. The seeds, known as PSYLLIUM, swell in water and are used as laxatives. The leaves have been used medicinally.Eucalyptus: A genus of trees of the Myrtaceae family, native to Australia, that yields gums, oils, and resins which are used as flavoring agents, astringents, and aromatics.Bignoniaceae: A plant family of the order Lamiales. The family is characterized by oppositely paired, usually compound leaves and bell- or funnel-shaped, bisexual flowers having a five-lobed calyx and corolla.Arabidopsis Proteins: Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.Tobacco: A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.Brassica napus: A plant species of the family BRASSICACEAE best known for the edible roots.Cell Wall: The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.Papaveraceae: The poppy plant family of the order Papaverales, subclass Magnoliidae, class Magnoliopsida. These have bisexual, regular, cup-shaped flowers with one superior pistil and many stamens; 2 or 3 conspicuous, separate sepals and a number of separate petals. The fruit is a capsule. Leaves are usually deeply cut or divided into leaflets.Plant Bark: The outer layer of the woody parts of plants.Angiosperms: Members of the group of vascular plants which bear flowers. They are differentiated from GYMNOSPERMS by their production of seeds within a closed chamber (OVARY, PLANT). The Angiosperms division is composed of two classes, the monocotyledons (Liliopsida) and dicotyledons (Magnoliopsida). Angiosperms represent approximately 80% of all known living plants.Lycopersicon esculentum: A plant species of the family SOLANACEAE, native of South America, widely cultivated for their edible, fleshy, usually red fruit.Vitamin U: A vitamin found in green vegetables. It is used in the treatment of peptic ulcers, colitis, and gastritis and has an effect on secretory, acid-forming, and enzymatic functions of the intestinal tract.Vicia faba: A plant species of the genus VICIA, family FABACEAE. The edible beans are well known but they cause FAVISM in some individuals with GLUCOSEPHOSPHATE DEHYDROGENASE DEFICIENCY. This plant contains vicine, convicine, Vicia lectins, unknown seed protein, AAP2 transport protein, and Vicia faba DNA-binding protein 1.Ranunculaceae: The buttercup plant family of the order Ranunculales, subclass Magnoliidae, class Magnoliopsida. The leaves are usually alternate and stalkless. The flowers usually have two to five free sepals and may be radially symmetrical or irregular.Genes, Plant: The functional hereditary units of PLANTS.Prunus: A plant genus in the family ROSACEAE, order Rosales, subclass Rosidae. It is best known as a source of edible fruits such as apricot, plum, peach, cherry, and almond.Botany: The study of the origin, structure, development, growth, function, genetics, and reproduction of plants.Asteraceae: A large plant family of the order Asterales, subclass Asteridae, class Magnoliopsida. The family is also known as Compositae. Flower petals are joined near the base and stamens alternate with the corolla lobes. The common name of "daisy" refers to several genera of this family including Aster; CHRYSANTHEMUM; RUDBECKIA; TANACETUM.RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Actinidia: A plant species of the family ACTINIDIACEAE, order Theales.Plants: Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.Gymnosperms: Gymnosperms are a group of vascular plants whose seeds are not enclosed by a ripened ovary (fruit), in contrast to ANGIOSPERMS whose seeds are surrounded by an ovary wall. The seeds of many gymnosperms (literally, "naked seed") are borne in cones and are not visible. Taxonomists now recognize four distinct divisions of extant gymnospermous plants (CONIFEROPHYTA; CYCADOPHYTA; GINKGOPHYTA; and GNETOPHYTA).Abscisic Acid: Abscission-accelerating plant growth substance isolated from young cotton fruit, leaves of sycamore, birch, and other plants, and from potatoes, lemons, avocados, and other fruits.Malus: A plant genus in the family ROSACEAE, order Rosales, subclass Rosidae. It is best known as a source of the edible fruit (apple) and is cultivated in temperate climates worldwide.Phytoplasma: A genus of minute bacteria in the family ACHOLEPLASMATACEAE that inhabit phloem sieve elements of infected PLANTS and cause symptoms such as yellowing, phyllody, and witches' brooms. Organisms lack a CELL WALL and thus are similar to MYCOPLASMA in animals. They are transmitted by over 100 species of INSECTS especially leafhoppers, planthoppers, and PSYLLIDS.Elements: Substances that comprise all matter. Each element is made up of atoms that are identical in number of electrons and protons and in nuclear charge, but may differ in mass or number of neutrons.Plant Physiological Phenomena: The physiological processes, properties, and states characteristic of plants.Verbascum: A plant genus of the family SCROPHULARIACEAE.Lamiaceae: The mint plant family. They are characteristically aromatic, and many of them are cultivated for their oils. Most have square stems, opposite leaves, and two-lipped, open-mouthed, tubular corollas (united petals), with five-lobed, bell-like calyxes (united sepals).Boron: A trace element with the atomic symbol B, atomic number 5, and atomic weight [10.806; 10.821]. Boron-10, an isotope of boron, is used as a neutron absorber in BORON NEUTRON CAPTURE THERAPY.Verticillium: A mitosporic fungal genus commonly isolated from soil. Some species are the cause of wilt diseases in many different plants.Plant Growth Regulators: Any of the hormones produced naturally in plants and active in controlling growth and other functions. There are three primary classes: auxins, cytokinins, and gibberellins.Flowers: The reproductive organs of plants.Cucumis: A plant genus of the family CUCURBITACEAE, order Violales, subclass Dilleniidae best known for cucumber (CUCUMIS SATIVUS) and cantaloupe (CUCUMIS MELO). Watermelon is a different genus, CITRULLUS. Bitter melon may refer to MOMORDICA or this genus.Inflorescence: A cluster of FLOWERS (as opposed to a solitary flower) arranged on a main stem of a plant.Seedling: Very young plant after GERMINATION of SEEDS.Larix: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta.Citrus: A plant genus of the family RUTACEAE. They bear the familiar citrus fruits including oranges, grapefruit, lemons, and limes. There are many hybrids which makes the nomenclature confusing.Plant Cells: Basic functional unit of plants.Eucommiaceae: A plant family of the order Eucommiales, subclass Hamamelidae, class Magnoliopsida (some botanists have classified this in the order Hamamelidales or Urticales). Eucomia is an elmlike tree of central and eastern China. Leaves are alternate; deciduous flowers are solitary and unisexual and lack petals and sepals. The male flowers have 6 to 10 stamens and female flowers have one ovary of two carpels, one of which aborts during development so the fruit (a dry, winged structure) contains only one seed. The latex is a source of RUBBER. Tochu tea is an aqueous extract of Eucommia ulmoides leaves and a popular beverage in Japan. (Mutat Res 1997 Jan 15;388(1):7-20).Nerium: A plant genus of the family APOCYNACEAE. It is a very poisonous plant that contains cardioactive agents.Clethraceae: A plant family of the order Ericales, subclass Dilleniidae, class Magnoliopsida.Meristem: A group of plant cells that are capable of dividing infinitely and whose main function is the production of new growth at the growing tip of a root or stem. (From Concise Dictionary of Biology, 1990)Indoleacetic Acids: Acetic acid derivatives of the heterocyclic compound indole. (Merck Index, 11th ed)Plant Components, Aerial: The above-ground plant without the roots.Zea mays: A plant species of the family POACEAE. It is a tall grass grown for its EDIBLE GRAIN, corn, used as food and animal FODDER.Liquidambar: A plant genus of the family HAMAMELIDACEAE. The sap is a source of storax, which should not be confused with the similar named STYRAX genus.Oryza sativa: Annual cereal grass of the family POACEAE and its edible starchy grain, rice, which is the staple food of roughly one-half of the world's population.Droughts: Prolonged dry periods in natural climate cycle. They are slow-onset phenomena caused by rainfall deficit combined with other predisposing factors.Hypocotyl: The region of the stem beneath the stalks of the seed leaves (cotyledons) and directly above the young root of the embryo plant. It grows rapidly in seedlings showing epigeal germination and lifts the cotyledons above the soil surface. In this region (the transition zone) the arrangement of vascular bundles in the root changes to that of the stem. (From Concise Dictionary of Biology, 1990)Solanum tuberosum: A plant species of the genus SOLANUM, family SOLANACEAE. The starchy roots are used as food. SOLANINE is found in green parts.Citrullus: A plant genus of the family CUCURBITACEAE known for the edible fruit.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
  • Additionally, aphids did not demonstrate a preference between artificial diets with low or high levels of dissolved oxygen, making it unlikely that oxygen gradients in the cortex assist orientation towards the phloem. (biologists.org)
  • The differences in vascular bundles organisation, parenchymatic pith development in the root centre and the reduction of phloem part of vascular bundles were well observable. (mdpi.com)
  • The leaves draw water from the ground in the transpiration stream through a vascular conducting system known as xylem and obtain carbon dioxide from the atmosphere by diffusion through openings called stomata in the outer covering layer of the leaf ( epidermis ), while leaves are orientated to maximize their exposure to sunlight. (wikipedia.org)
  • For efficient translocation to seeds, amino acids are loaded into the phloem in source leaves and along the long distance transport pathway through xylem-phloem transfer. (plantcell.org)
  • AAP2 T-DNA insertion lines showed changes in source-sink translocation of amino acids and a decrease in the amount of seed total N and storage proteins, supporting AAP2 function in phloem loading and amino acid distribution to the embryo. (plantcell.org)
  • This minimal model predicts a power law phloem distribution consistent with transport energy minimization, suggesting that energetics are more important than translocation speed at the leaf level. (royalsocietypublishing.org)
  • Plants have two networks of 'fine tubes' to transport molecules and ions (xylem tubes and phloem tubes). (docbrown.info)
  • The expression of EPFL4 or EPFL6 in the endodermis, a layer adjacent to phloem, is sufficient to rescue the er -like inflorescence of epfl4 epfl6 plants. (pnas.org)
  • In larger plants such as trees , the root pressure and transpirational pull work together as a pump that pulls xylem sap from the soil up to where it is transpired. (newworldencyclopedia.org)
  • Hormone treatment examinations verified that xylem phenotypes in PdC3H17 transgenic plants, which were readily apparent in normal condition, were attenuated by treatment with either brassinolide or the BR biosynthesis inhibitor propiconazole. (frontiersin.org)
  • Aphids ( Aphis fabae ) ingested less phloem sap of plants transporting hexoses compared with plants transporting the normal sucrose. (biologists.org)
  • RPN9 -silenced plants display extra leaf vein formation with increased xylem and decreased phloem. (plantphysiol.org)
  • Similar phenotypes, including discontinuous formation of xylem vessels ( Fig. 1 F ) and stele enlargement ( Fig. 1 U ), were also observed in transgenic plants overexpressing CLE44 . (pnas.org)
  • The leaders of 50 plants were destructively sampled and the resin canal density, the canal area and its relative conductive area in the phloem and xylem were assessed. (csic.es)
  • Experimentally increased nutrient availability significantly decreased resin canal density in the phloem of the seedlings in the two analysed trials, where unfertilised seedlings presented up to 30% more resin canal density than the fertilised seedlings (mean value ± SEM = 0.32 ± 0.02 resin canals mm−2 in the fertilised plants versus 0.45 ± 0.04 resin canals mm−2 in the control plants). (csic.es)
  • The Xylem is the other transport tube system in plants. (google.com)
  • The Xylem also take up the various minerals found in the soil that are essential for plants to grow. (google.com)
  • The water‐conducting function of xylem is one of the major distinguishing features of vascular plants. (els.net)
  • The phloem vascular system facilitates transport of energy-rich sugar and signalling molecules in plants, thus permitting long-range communication within the organism and growth of non-photosynthesizing organs such as roots and fruits. (royalsocietypublishing.org)
  • The role of the phloem in the transport of photoassimlates has been known since the seventeenth century [ 2 ], but it was not until 1930 that the role of the phloem sieve element as the channel of carbohydrate transport in plants was experimentally demonstrated [ 3 - 5 ]. (royalsocietypublishing.org)
  • The morphology, frequency and distribution of xylem cell types determine its biological, physical and chemical properties, and the resulting properties of wood. (els.net)
  • They are also found in xylem, and are the main component of many textiles such as paper, linen, and cotton. (wikipedia.org)
  • Our results suggest that intercell layer communication between the endodermis and phloem mediated by peptide ligands and a receptor kinase coordinates proper inflorescence architecture in Arabidopsis . (pnas.org)
  • Here we report that proper inflorescence architecture in Arabidopsis can be specified by intertissue layer communication between the phloem and the endodermis mediated by ER and its signaling ligands, EPFL4 and EPFL6, 2 of the 11 members of the EPFL family of secreted cysteine-rich peptides (CRPs) ( 9 , 14 , 15 ). (pnas.org)
  • 綱 綱 綱 綱 Protostele: Haplostele  the simplest protostele  this consists of a solid core of xylem surrounded by a layer of phloem  an endodermis surrounds the stele  ex. (coursehero.com)
  • In this way, three main behavioural phases of functionally related activities (pathway, xylem and phloem phase) were identified ( Tjallingii, 2006 ). (biologists.org)
  • The xylem cell walls are strengthened by a material lignin. (docbrown.info)
  • The onset of phloem cell production occurred in early and mid-May in southern and northern Finland, respectively. (springer.com)
  • Exogenous 24-epibrassinolide (BL) and brassinazole (BRZ) have regulatory roles in G-fiber cell wall development and secondary xylem cell wall carbohydrate biosynthesis during tension wood formation in hybrid poplar. (springer.com)
  • Wood chemistry analyses and immunolocalization demonstrated that BL and BRZ treatments increased the cellulose content and modified the deposition of cell wall carbohydrates including arabinose, galactose and rhamnose in the secondary xylem. (springer.com)
  • the living material in the interior disintegrates, leaving behind thickened cell walls through which xylem sap flows. (newworldencyclopedia.org)
  • A vascular-specific Gly-rich protein inhibits the long-distance movement of Turnip vein - clearing virus , probably by inducing callose accumulation in the phloem cell walls ( Ueki and Citovsky, 2002 ). (plantphysiol.org)
  • However, little is known about the molecular mechanism of cell communication governing xylem-phloem patterning. (pnas.org)
  • Our results indicate that we have discovered a cell communication system governing phloem-xylem cross-talk. (pnas.org)
  • The physical differences is that Xylem has more of a hard cell wall while Phloem has a softer cell wall. (kongregate.com)
  • This model describes a series of radial, transverse and tangential walls in the xylem that ultimately confine the putative pathogen and its damages, resisting their spread. (biomedcentral.com)