Mycorrhizae: Symbiotic combination (dual organism) of the MYCELIUM of FUNGI with the roots of plants (PLANT ROOTS). The roots of almost all higher plants exhibit this mutually beneficial relationship, whereby the fungus supplies water and mineral salts to the plant, and the plant supplies CARBOHYDRATES to the fungus. There are two major types of mycorrhizae: ectomycorrhizae and endomycorrhizae.Glomeromycota: A phylum of fungi that are mutualistic symbionts and form ARBUSCULAR MYCORRHIZAE with PLANT ROOTS.Symbiosis: The relationship between two different species of organisms that are interdependent; each gains benefits from the other or a relationship between different species where both of the organisms in question benefit from the presence of the other.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)Corylus: A plant genus of the family BETULACEAE known for the edible nuts.Ericaceae: The heath plant family of the order Ericales, subclass Dilleniidae, class Magnoliopsida that are generally shrubs or small trees. Leaves are alternate, simple, and leathery; flowers are symmetrical with a 4- or 5-parted corolla of partly fused petals.Lotus: A plant genus of the family FABACEAE. This genus was formerly known as Tetragonolobus. The common name of lotus is also used for NYMPHAEA and NELUMBO.Daucus carota: A plant species of the family APIACEAE that is widely cultivated for the edible yellow-orange root. The plant has finely divided leaves and flat clusters of small white flowers.Fungi: A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including MUSHROOMS; YEASTS; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies.Polygonum: A plant genus of the family POLYGONACEAE that is an ingredient of Shou-Wu-Pian, a Chinese herbal preparation (DRUGS, CHINESE HERBAL). The common name of black bindweed also refers to TAMUS or Fallopia (use POLYGONACEAE).Basidiomycota: A phylum of fungi that produce their sexual spores (basidiospores) on the outside of the basidium. It includes forms commonly known as mushrooms, boletes, puffballs, earthstars, stinkhorns, bird's-nest fungi, jelly fungi, bracket or shelf fungi, and rust and smut fungi.Amanita: A genus of fungi of the family Agaricaceae, order Agaricales; most species are poisonous.Frankia: Genus of BACTERIA in the family Frankiaceae. They are nitrogen-fixing root-nodule symbionts of many species of woody dicotyledonous plants.Pseudotsuga: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are coniferous evergreen trees with long, flat, spirally arranged needles that grow directly from the branch.Pinus sylvestris: A plant species of the genus PINUS which is the source of pinosylvin. It is sometimes called Scotch pine or Scots pine, which is also a common name for other species of this genus.Medicago: A plant genus of the family FABACEAE. It is distinct from Sweet Clover (MELILOTUS), from Bush Clover (LESPEDEZA), and from Red Clover (TRIFOLIUM).Mycelium: The body of a fungus which is made up of HYPHAE.Medicago truncatula: A plant species of the family FABACEAE used to study GENETICS because it is DIPLOID, self fertile, has a small genome, and short generation time.Biomass: Total mass of all the organisms of a given type and/or in a given area. (From Concise Dictionary of Biology, 1990) It includes the yield of vegetative mass produced from any given crop.Soil: The unconsolidated mineral or organic matter on the surface of the earth that serves as a natural medium for the growth of land plants.Orchidaceae: A plant family of the order Orchidales, subclass Liliidae, class Liliopsida (monocotyledons). All orchids have the same bilaterally symmetrical flower structure, with three sepals, but the flowers vary greatly in color and shape.Agaricales: An extensive order of basidiomycetous fungi whose fruiting bodies are commonly called mushrooms.Soil Microbiology: The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.Root Nodules, Plant: Knobbed structures formed from and attached to plant roots, especially of LEGUMES, which result from symbiotic infection by nitrogen fixing bacteria such as RHIZOBIUM or FRANKIA. Root nodules are structures related to MYCORRHIZAE formed by symbiotic associations with fungi.Trees: Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.Plant Shoots: New immature growth of a plant including stem, leaves, tips of branches, and SEEDLINGS.Phosphorus: A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.Ascomycota: A phylum of fungi which have cross-walls or septa in the mycelium. The perfect state is characterized by the formation of a saclike cell (ascus) containing ascospores. Most pathogenic fungi with a known perfect state belong to this phylum.Nitrogen: An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.Spores, Fungal: Reproductive bodies produced by fungi.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.Seedling: Very young plant after GERMINATION of SEEDS.DNA, Ribosomal Spacer: The intergenic DNA segments that are between the ribosomal RNA genes (internal transcribed spacers) and between the tandemly repeated units of rDNA (external transcribed spacers and nontranscribed spacers).Lycopersicon esculentum: A plant species of the family SOLANACEAE, native of South America, widely cultivated for their edible, fleshy, usually red fruit.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Genes, Plant: The functional hereditary units of PLANTS.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.DNA, Fungal: Deoxyribonucleic acid that makes up the genetic material of fungi.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.