Cytokinins: Plant hormones that promote the separation of daughter cells after mitotic division of a parent cell. Frequently they are purine derivatives.Zeatin: An aminopurine factor in plant extracts that induces cell division. (Grant & Hackh's Chemical Dict, 5th ed)Kinetin: A furanyl adenine found in PLANTS and FUNGI. It has plant growth regulation effects.Isopentenyladenosine: N(6)-[delta(3)-isopentenyl]adenosine. Isopentenyl derivative of adenosine which is a member of the cytokinin family of plant growth regulators.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.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)Plant Shoots: New immature growth of a plant including stem, leaves, tips of branches, and SEEDLINGS.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)Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Helleborus: A plant genus of the family RANUNCULACEAE. Members contain hellebrin (BUFANOLIDES). The extract is the basis of Boicil preparation used to treat rheumatism.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.Indoleacetic Acids: Acetic acid derivatives of the heterocyclic compound indole. (Merck Index, 11th ed)Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.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.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)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.Alkyl and Aryl Transferases: A somewhat heterogeneous class of enzymes that catalyze the transfer of alkyl or related groups (excluding methyl groups). EC 2.5.Adenine: A purine base and a fundamental unit of ADENINE NUCLEOTIDES.Scopoletin: Plant growth factor derived from the root of Scopolia carniolica or Scopolia japonica.Crassulaceae: The stonecrop plant family of the order ROSALES, subclass Rosidae, class Magnoliopsida that grow in warm, dry regions. The leaves are thick. The flower clusters are red, yellow, or white.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.Tobacco: A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.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.Coleus: A plant genus of the family Lamiaceae. The species of Coleus should be distinguished from PLECTRANTHUS BARBATUS - which is also known as Coleus forskohlii.Seedling: Very young plant after GERMINATION of SEEDS.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)Sophora: A plant genus of the family FABACEAE.Genes, Plant: The functional hereditary units of PLANTS.Naphthaleneacetic Acids: Naphthalene derivatives containing the -CH2CCO2H radical at the 1-position, the 2-position, or both. Compounds are used as plant growth regulators to delay sprouting, exert weed control, thin fruit, etc.Photoreceptors, Plant: Plant proteins that mediate LIGHT SIGNAL TRANSDUCTION. They are involved in PHOTOTROPISM and other light adaption responses during plant growth and development . They include the phototropins, phytochromes (PHYTOCHROME), and members of the ubiquitous cryptochrome family.Plant Development: Processes orchestrated or driven by a plethora of genes, plant hormones, and inherent biological timing mechanisms facilitated by secondary molecules, which result in the systematic transformation of plants and plant parts, from one stage of maturity to another.Plants, Toxic: Plants or plant parts which are harmful to man or other animals.Bryopsida: A class of plants within the Bryophyta comprising the mosses, which are found in both damp (including freshwater) and drier situations. Mosses possess erect or prostrate leafless stems, which give rise to leafless stalks bearing capsules. Spores formed in the capsules are released and grow to produce new plants. (Concise Dictionary of Biology, 1990). Many small plants bearing the name moss are in fact not mosses. The "moss" found on the north side of trees is actually a green alga (CHLOROPHYTA). Irish moss is really a red alga (RHODOPHYTA). Beard lichen (beard moss), Iceland moss, oak moss, and reindeer moss are actually LICHENS. Spanish moss is a common name for both LICHENS and an air plant (TILLANDSIA usneoides) of the pineapple family. Club moss is an evergreen herb of the family LYCOPODIACEAE.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.Oxidoreductases: The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)Seeds: The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.Plant Tumors: A localized proliferation of plant tissue forming a swelling or outgrowth, commonly with a characteristic shape and unlike any organ of the normal plant. Plant tumors or galls usually form in response to the action of a pathogen or a pest. (Holliday, P., A Dictionary of Plant Pathology, 1989, p330)RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Flowers: The reproductive organs of plants.Benzyl CompoundsPlant Immunity: The inherent or induced capacity of plants to withstand or ward off biological attack by pathogens.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)beta-Fructofuranosidase: A glycoside hydrolase found primarily in PLANTS and YEASTS. It has specificity for beta-D-fructofuranosides such as SUCROSE.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.Ethylenes: Derivatives of ethylene, a simple organic gas of biological origin with many industrial and biological use.Plant Structures: The parts of plants, including SEEDS.Gibberellins: A class of plant growth hormone isolated from cultures of Gibberella fujikuroi, a fungus causing Bakanae disease in rice. There are many different members of the family as well as mixtures of multiple members; all are diterpenoid acids based on the gibberellane skeleton.Chlorophyll: Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.Glucosides