| Armillaria fuscipes | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Basidiomycota |
| Class: | Agaricomycetes |
| Order: | Agaricales |
| Family: | Physalacriaceae |
| Genus: | Armillaria |
| Species: | A. fuscipes |
| Binomial name | |
| Armillaria fuscipes Petch (1909) | |
Armillaria fuscipes is a plant pathogen that causes Armillaria root rot on Pinus , coffee plants, tea and various hardwood trees. It is common in South Africa. [1] The mycelium of the fungus is bioluminescent. [2]
Armillaria root rot is a disease that affects a wide variety of trees and is caused by multiple species in the Armillaria species complex. Armillaria spp. is a basidiomycete fungi. The symptoms for Armillaria spp. can vary greatly because of the wide host range and different species of pathogen. The hosts of Armillaria fuscipes specifically are tropical members of the genus Pinus, Camellia sinensis (tea), and members of the genus Coffea. [3] General symptoms of A. fuscipes, include stunting of the plant, sparse foliage and chlorosis of the leaves. [4] For hosts in the Pinus genus, such as Pinus elliottii, P. kesiya, P. patula, P. taeda, chlorosis of the needles of the infected plant is also a common symptom. [5] Signs of this pathogen are white fans of hyphae that grow between the bark and wood of infected trees as well as the black mycelial cord or rhizomorph of the fungi growing in a net around the root system. [6] The mycelium of A. fuscipes are bioluminescent and the rhizomorph is used to transfer nutrients over large distances to create fruiting bodies as well as infect other trees. The fruiting bodies are brown and white mushrooms that emerge from the base of the tree. The cracking of bark and resin leaking from the base of the tree are other symptoms seen mostly in the Pinus hosts.
Armillaria root rot caused by this A. fuscipes can result in the death of many Pinus species native to South Africa. The disease can spread from one tree to many and result in patches of dead trees of a considerable area. [5] A. fuscipes is the major cause of armillaria root rot on tea in Kenya and has been found in other African countries. This has major economic implications for the tea industry in countries where the pathogen is prevalent, especially because of its wide distribution in Africa ranging from South Africa to as far north as Ethiopia. [3] Kenya is the largest producer of tea in Africa, which accounts for 17–20% of the revenue made from exports. [7] The way the disease spreads and symptoms, which greatly affect yield, make it an important disease to control, primarily in places where the plants it affects are of economic importance. A. fuscipes can infect coffee plants as well, but it mostly affects stands of tea.
Managing A. fuscipes can be difficult because removing the pathogen via the application of fungicides isn't very straight forward. While fumigation of the plants is an option for control, it isn't often used because many fumigants, such as methyl bromide, are banned due to their extreme toxicity and the adverse effects they have on the environment. Another option for controlling inoculum is mechanical removal of infected stumps and plant material. It is difficult to completely eradicate the pathogen in this manner and it is invasive, expensive and labor-intensive. Some newer and more promising methods of management include solarization of the soil and the application of Trichoderma harzianum to the soil as a biological control. In a German study, it was found that solarization for 10 weeks increased the soil temperature enough that the viability of the pathogen was almost eliminated. The application of T. harzianum was effective in controlling A. fuscipes in woody species, and when combined with 5 weeks of solarization, caused a total loss of pathogen viability. [7] Breeding for resistance and increasing host vigor are also options for long term management of this pathogen.
Armillaria is a genus of fungi that includes the A. mellea species known as honey fungi that live on trees and woody shrubs. It includes about 10 species formerly categorized summarily as A. mellea. Armillarias are long-lived and form the largest living fungi in the world. The largest known organism covers more than 3.4 square miles (8.8 km2) in Oregon's Malheur National Forest and is estimated to be 2,500 years old. Some species of Armillaria display bioluminescence, resulting in foxfire.
Armillaria mellea, commonly known as honey fungus, is an edible basidiomycete fungus in the genus Armillaria. It is a plant pathogen and part of a cryptic species complex of closely related and morphologically similar species. It causes Armillaria root rot in many plant species and produces mushrooms around the base of trees it has infected. The symptoms of infection appear in the crowns of infected trees as discoloured foliage, reduced growth, dieback of the branches and death. The mushrooms are edible but some people may be intolerant to them. This species is capable of producing light via bioluminescence in its mycelium.
Fusarium wilt is a common vascular wilt fungal disease, exhibiting symptoms similar to Verticillium wilt. This disease has been investigated extensively since the early years of this century. The pathogen that causes Fusarium wilt is Fusarium oxysporum. The species is further divided into formae speciales based on host plant.
Mycelial cords are linear aggregations of parallel-oriented hyphae. The mature cords are composed of wide, empty vessel hyphae surrounded by narrower sheathing hyphae. Cords may look similar to plant roots, and also frequently have similar functions; hence they are also called rhizomorphs. As well as growing underground or on the surface of trees and other plants, some fungi make mycelial cords which hang in the air from vegetation.
Armillaria luteobubalina, commonly known as the Australian honey fungus, is a species of mushroom in the family Physalacriaceae. Widely distributed in southern Australia, the fungus is responsible for a disease known as Armillaria root rot, a primary cause of Eucalyptus tree death and forest dieback. It is the most pathogenic and widespread of the six Armillaria species found in Australia. The fungus has also been collected in Argentina and Chile. Fruit bodies have cream- to tan-coloured caps that grow up to 10 cm (4 in) in diameter and stems that measure up to 20 cm (8 in) long by 1.5 cm (1 in) thick. The fruit bodies, which appear at the base of infected trees and other woody plants in autumn (March–April), are edible, but require cooking to remove the bitter taste. The fungus is dispersed through spores produced on gills on the underside of the caps, and also by growing vegetatively through the root systems of host trees. The ability of the fungus to spread vegetatively is facilitated by an aerating system that allows it to efficiently diffuse oxygen through rhizomorphs—rootlike structures made of dense masses of hyphae.
Armillaria tabescens is a species of fungus in the family Physalacriaceae. It is a plant pathogen. The mycelium of the fungus is bioluminescent.
Phytophthora cactorum is a fungal-like plant pathogen belonging to the Oomycota phylum. It is the causal agent of root rot on rhododendron and many other species, as well as leather rot of strawberries.
Pythium aphanidermatum is a soil borne plant pathogen. Pythium is a genus in the class Oomycetes, which are also known as water molds. Oomycetes are not true fungi, as their cell walls are made of cellulose instead of chitin, they are diploid in their vegetative state, and they form coenocytic hyphae. Also, they reproduce asexually with motile biflagelette zoospores that require water to move towards and infect a host. Sexually, they reproduce with structures called antheridia, oogonia, and oospores.
Rosellinia bunodes is a plant pathogen infecting several hosts including avocados, bananas, cacao and tea.
Rigidoporus microporus is a plant pathogen, known to cause white root rot disease on various tropical crops, such as cacao, cassava, tea, with economical importance on the para rubber tree.
Armillaria sinapina is a species of mushroom in the family Physalacriaceae. A plant pathogenic fungus, it causes Armillaria root disease, and has been found on a variety of tree hosts in Alaska. The mycelium of the fungus is bioluminescent.
Armillaria novae-zelandiae is a species of mushroom-forming fungus in the family Physalacriaceae. This plant pathogen species is one of three Armillaria species that have been identified in New Zealand.
Armillaria gallica is a species of honey mushroom in the family Physalacriaceae of the order Agaricales. The species is a common and ecologically important wood-decay fungus that can live as a saprobe, or as an opportunistic parasite in weakened tree hosts to cause root or butt rot. It is found in temperate regions of Asia, North America, and Europe. The species forms fruit bodies singly or in groups in soil or rotting wood. The fungus has been inadvertently introduced to South Africa. Armillaria gallica has had a confusing taxonomy, due in part to historical difficulties encountered in distinguishing between similar Armillaria species. The fungus received international attention in the early 1990s when an individual colony living in a Michigan forest was reported to cover an area of 15 hectares, weigh at least 9.5 tonnes, and be 1,500 years old. This individual is popularly known as the "humongous fungus", and is a tourist attraction and inspiration for an annual mushroom-themed festival in Crystal Falls. Recent studies have revised the fungus's age to 2,500 years and its size to about 400 tonnes, four times the original estimate.
Forest pathology is the research of both biotic and abiotic maladies affecting the health of a forest ecosystem, primarily fungal pathogens and their insect vectors. It is a subfield of forestry and plant pathology.
Armillaria root rot is a fungal root rot caused by several different members of the genus Armillaria. The symptoms are variable depending on the host infected, ranging from stunted leaves to chlorotic needles and dieback of twigs and branches. However, all infected hosts display symptoms characteristic of being infected by a white rotting fungus. The most effective ways of management focus on limiting the spread of the fungus, planting resistant species, and removing infected material. This disease poses a threat to the lumber industry as well as affecting recreational areas.
Armillaria ostoyae is a species of fungus (mushroom), pathogenic to trees, in the family Physalacriaceae. In the western United States, it is the most common variant of the group of species under the name Armillaria mellea. A. ostoyae is common on both hardwood and conifer wood in forests west of the Cascade Range in Oregon, United States. It has decurrent gills and the stipe has a ring. The mycelium invades the sapwood and is able to disseminate over great distances under the bark or between trees in the form of black rhizomorphs ("shoestrings"). In most areas of North America, Armillaria ostoyae can be separated from other species by its physical features: cream-brown colors, prominent cap scales, and a well-developed stem ring distinguish it from other Armillaria. Like several other Armillaria, the mycelium of Armillaria ostoyae can display bioluminescence, resulting in foxfire.
Fusarium circinatum is a fungal plant pathogen that causes the serious disease pitch canker on pine trees and Douglas firs. The most common hosts of the pathogen include slash pine, loblolly pine, Monterey pine, Mexican weeping pine, and Douglas fir. Like other Fusarium species in the phylum Ascomycota, it is the asexual reproductive state of the fungus and has a teleomorph, Gibberella circinata.
Helicobasidium is a genus of fungi in the subdivision Pucciniomycotina. Basidiocarps are corticioid (patch-forming) and are typically violet to purple. Microscopically they have auricularioid basidia. Asexual anamorphs, formerly referred to the genus Thanatophytum, produce sclerotia. Conidia-bearing anamorphs are parasitic on rust fungi and are currently still referred to the genus Tuberculina.
Black rot on orchids is caused by Pythium and Phytophthora species. Black rot targets a variety of orchids but Cattleya orchids are especially susceptible. Pythium ultimum and Phytophthora cactorum are known to cause black rot in orchids.