A mycorrhiza is a symbiotic association between a fungus and a plant. The term mycorrhiza refers to the role of the fungus in the plant's rhizosphere, the plant root system and its surroundings. Mycorrhizae play important roles in plant nutrition, soil biology, and soil chemistry.
Howea forsteriana, the Kentia palm, thatch palm or palm court palm, is a species of flowering plant in the palm family, Arecaceae, endemic to Lord Howe Island in Australia. It is also widely grown on Norfolk Island. It is a relatively slow-growing palm, eventually growing up to 10 m (33 ft) tall by 6 m (20 ft) wide. Its fronds can reach 3 m (10 ft) long. The palm gets its common name from the capital of Lord Howe Island, Kentia, and the genus name, Howea, from the island itself. The species name “forsteriana" is after Johann Reinhold Forster and Georg Forster, father and son, who accompanied Captain Cook as naturalists on his second voyage to the Pacific in 1772–1775.
Lord Howe Island is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, part of the Australian state of New South Wales. It lies 600 km (320 nmi) directly east of mainland Port Macquarie, 780 km (420 nmi) northeast of Sydney, and about 900 km (490 nmi) southwest of Norfolk Island. It is about 10 km (6.2 mi) long and between 0.3 and 2.0 km wide with an area of 14.55 km2, though just 3.98 km2 of that comprise the low-lying developed part of the island.
Howea is a genus of two palms, H. belmoreana and H. forsteriana, both endemic to Lord Howe Island, Australia. H. forsteriana in particular is commonly grown as an indoor plant in the Northern Hemisphere, and the two species form the mainstay of the island's palm seed industry and more importantly its trade in newly germinated seedlings. The palms are also cultivated on Norfolk Island, where seeds are produced for export.
An arbuscular mycorrhiza (AM) is a type of mycorrhiza in which the symbiont fungus penetrates the cortical cells of the roots of a vascular plant forming arbuscules. Arbuscular mycorrhiza is a type of endomycorrhiza along with ericoid mycorrhiza and orchid mycorrhiza. They are characterized by the formation of unique tree-like structures, the arbuscules. In addition, globular storage structures called vesicles are often encountered.
Glomeromycota are one of eight currently recognized divisions within the kingdom Fungi, with approximately 230 described species. Members of the Glomeromycota form arbuscular mycorrhizas (AMs) with the thalli of bryophytes and the roots of vascular land plants. Not all species have been shown to form AMs, and one, Geosiphon pyriformis, is known not to do so. Instead, it forms an endocytobiotic association with Nostoc cyanobacteria. The majority of evidence shows that the Glomeromycota are dependent on land plants for carbon and energy, but there is recent circumstantial evidence that some species may be able to lead an independent existence. The arbuscular mycorrhizal species are terrestrial and widely distributed in soils worldwide where they form symbioses with the roots of the majority of plant species (>80%). They can also be found in wetlands, including salt-marshes, and associated with epiphytic plants.
Ophrys insectifera, the fly orchid, is a species of orchid and the type species of the genus Ophrys. It is remarkable as an example of the use of sexually deceptive pollination and floral mimicry, as well as a highly selective and highly evolved plant–pollinator relationship.
Celastrus orbiculatus is a woody vine of the family Celastraceae. It is commonly called Oriental bittersweet, as well as Chinese bittersweet, Asian bittersweet, round-leaved bittersweet, and Asiatic bittersweet.
Glomus aggregatum is an arbuscular mycorrhizal fungus used as a soil inoculant in agriculture and horticulture. Like other species in this phylum it forms obligate symbioses with plant roots, where it obtains carbon (photosynthate) from the host plant in exchange for nutrients and other benefits.
Hedyscepe canterburyana, the big mountain palm or umbrella palm, is the sole species in the genus Hedyscepe of the family Arecaceae. It is endemic to Lord Howe Island, Australia and is threatened by habitat loss. It is a solitary palm with a distinct crownshaft, and bears unisexual flowers of both sexes. With the Rhopalostylis palms of Norfolk Island and New Zealand it forms the botanic subtribe Rhopalostylidinae. If differs from Rhopalostylis in minor floral details including having more than six stamens, and in being protandrous rather than protogynous. The two genera were formerly included in Archontophoenicinae until a recent revision. In some molecular phylogenetic analyses, Hedyscepe was found to be nested in the New Caledonia endemic Basselinia.
The Gibraltar Botanic Gardens or La Alameda Gardens are a botanical garden in Gibraltar, spanning around 6 hectares. The Rock Hotel lies above the park.
Microbial inoculants, also known as soil inoculants or bioinoculants, are agricultural amendments that use beneficial rhizosphericic or endophytic microbes to promote plant health. Many of the microbes involved form symbiotic relationships with the target crops where both parties benefit (mutualism). While microbial inoculants are applied to improve plant nutrition, they can also be used to promote plant growth by stimulating plant hormone production. Although bacterial and fungal inoculants are common, inoculation with archaea to promote plant growth is being increasingly studied.
Nitrogen nutrition in the arbuscular mycorrhizal system refers to...
A mycorrhizal network is an underground network found in forests and other plant communities, created by the hyphae of mycorrhizal fungi joining with plant roots. This network connects individual plants together. Mycorrhizal relationships are most commonly mutualistic, with both partners benefiting, but can be commensal or parasitic, and a single partnership may change between any of the three types of symbiosis at different times.
Soil carbon storage is an important function of terrestrial ecosystems. Soil contains more carbon than plants and the atmosphere combined. Understanding what maintains the soil carbon pool is important to understand the current distribution of carbon on Earth, and how it will respond to environmental change. While much research has been done on how plants, free-living microbial decomposers, and soil minerals affect this pool of carbon, it is recently coming to light that mycorrhizal fungi—symbiotic fungi that associate with roots of almost all living plants—may play an important role in maintaining this pool as well. Measurements of plant carbon allocation to mycorrhizal fungi have been estimated to be 5 to 20% of total plant carbon uptake, and in some ecosystems the biomass of mycorrhizal fungi can be comparable to the biomass of fine roots. Recent research has shown that mycorrhizal fungi hold 50 to 70 percent of the total carbon stored in leaf litter and soil on forested islands in Sweden. Turnover of mycorrhizal biomass into the soil carbon pool is thought to be rapid and has been shown in some ecosystems to be the dominant pathway by which living carbon enters the soil carbon pool.
An ectomycorrhiza is a form of symbiotic relationship that occurs between a fungal symbiont, or mycobiont, and the roots of various plant species. The mycobiont is often from the phyla Basidiomycota and Ascomycota, and more rarely from the Zygomycota. Ectomycorrhizas form on the roots of around 2% of plant species, usually woody plants, including species from the birch, dipterocarp, myrtle, beech, willow, pine and rose families. Research on ectomycorrhizas is increasingly important in areas such as ecosystem management and restoration, forestry and agriculture.
Rhizophagus irregularis is an arbuscular mycorrhizal fungus used as a soil inoculant in agriculture and horticulture. Rhizophagus irregularis is also commonly used in scientific studies of the effects of arbuscular mycorrhizal fungi on plant and soil improvement. Until 2001, the species was known and widely marketed as Glomus intraradices, but molecular analysis of ribosomal DNA led to the reclassification of all arbuscular fungi from Zygomycota phylum to the Glomeromycota phylum.
Cenococcum geophilum Fr., synonym Cenococcum graniforme (Sow.) Ferd. and Winge, is an Ascomycete fungal species and is the only member in the genus Cenococcum. It is one of the most common ectomycorrhizal fungal species encountered in forest ecosystems. The geographic distribution of the species is notably cosmopolitan; it is found in ecosystems with a wide range of environmental conditions, and in many cases in high relative frequency. Because of its wide distribution and abundance in forest soils, it is one of the most well-studied ectomycorrhizal fungal species. While the species has long been known to be sterile and not produce asexual or sexual spores, cryptic sexual stages may exist. The hyphae produced by C. geophilum are characterized by their thick (1.5-8 um), straight and jet black appearance with little branching. They usually form monopodial (unbranched) ectomycorrhizas. The mantles of C. geophilum ectomycorrhizas are usually thick with few to many emanating hyphae.
Falko Feldmann is a German biologist and practitioner of phytomedicine. He is coordinator of matters concerning approval and registration of active substances and agents for plant protection, including international cooperation on questions about European Plant Protection Laws. He also holds the post of director of the Deutschen Phytomedizinischen Gesellschaft e.V. and is involved in a number of organisations and committees relevant to plant protection.
Mycorrhiza helper bacteria (MHB) are a group of organisms that form symbiotic associations with both ectomycorrhiza and arbuscular mycorrhiza. MHBs are diverse and belong to a wide variety of bacterial phyla including both Gram-negative and Gram-positive bacteria. Some of the most common MHBs observed in studies belong to the phylas Pseudomonas and Streptomyces. MHBs have been seen to have extremely specific interactions with their fungal hosts at times, but this specificity is lost with plants. MHBs enhance mycorrhizal function, growth, nutrient uptake to the fungus and plant, improve soil conductance, aid against certain pathogens, and help promote defense mechanisms. These bacteria are naturally present in the soil, and form these complex interactions with fungi as plant root development starts to take shape. The mechanisms through which these interactions take shape are not well-understood and needs further study.
