Basidiomycota
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COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE BASIDIOMYCOTA BY BANGAMOTI HANSDA ASSISTANT PROFESSOR DEPARTMENT OF BOTANY NARAJOLE RAJ COLLEGE BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE GENERAL CHARACTERISTICS The members included in the subdivision Basidiomycotina are characterised by the formation of basidiospores exogenously on the basidium and absence of flagelleted structure. The members include rusts, smuts, mushrooms, puffs balls, toad stools, bracket fungi etc. Presence of well developed, branched and septate mycelium having simple (e.g. Ustilaginales &Uredinales) or dolipore (e.g. Aphyllophorales & Auriculariaceae) septum. The mycelial cells may contain one nucleus, called monokaryotic i.e. primary mycelium or two nuclei, called dikaryotic i.e. secondary mycelium. The secondary mycelia may organise and form fruit body, called tertiary. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE The cell wall is mainly composed of chitin and glucans. Reproduction: (a) Vegetative reproduction takes place by budding and fragmentation. (b) Asexual reproduction takes place by conidia , oidia or chlamydospores that are absent in some higher taxa of this subdivision. (c) Sex organs are absent. During sexual reproduction, the dikaryotic cell is formed by somatogamy, spermatization or by buller phenomenon. Karyogamy occurs in basidium mother cell and forms diploid nucleus which is ephemeral. Basidiospores (4-haploid) are developed exogenously on the horn shaped structure, called sterigmata on the basidium. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Ecology of basidiomycota Basidiomycota are found in virtually all terrestrial ecosystems, as well as freshwater and marine habitats. They are an ecological and taxonomically diverse group. Most are. able to utilize simple carbohydrates, while filamentous species can decompose cellulose, hemicellulose and lignin. Many Basidiomycota obtain nutrition by decaying dead organic matter, including wood and leaf litter. Unfortunately, Basidiomycota frequently attack the wood in buildings and other structures, which has negative economic consequences for humans. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Systematic Position of Puccinia graminis tritici (Ainsworth, 1973) Puccinia graminis tritici is a heteroceious, macrocyclic, polymorphic and obligate parasite. It requires two host to finish its life cycle- The wheat plant (Triticum aestivum) The Barberry plant (Berberis vulgaris) Kingdom- Mycota Division- Basidiomycota Subdivision- Basidiomycotina Class-Teliomycetes Order- Uredinales Family- Pucciniaceae Genus- Puccinia Species- graminis tritci BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Symptoms on wheat plant Characterized by the presence of uredinia on the plant, which are brick-red, elongated, blister-like pustules that are easily shaken off. They most frequently occur on the leaf sheaths, but are also found on stems, leaves, glumes and awns. On leaf sheaths and glumes pustules rupture the epidermis, giving a ragged appearance. Towards the end of the growing season black telia are produced. For this reason stem rust is also known as 'black rust‘. The telia are firmly attached to the plant tissue. Symptoms on Barberry plant Pycnia appear on barberry plants in the spring, usually in the upper leaf surfaces. They are often in small clusters and exude pycniospores in a sticky honeydew. Five to ten days later, cup-shaped structures filled with orange- yellow, powdery aeciospores break through the lower leaf surface. The aecial cups are yellow and sometimes elongate to extend up to 5 mm from the leaf surface. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE The pathogen (Puccinia graminis tritici) can survive on straw of wheat plant, (the primary host), for several months as teleutospores, which then transfer the disease to the barberry (the alternate host). Teleutospores, on germination, produce the basidiospores of two opposite strains i.e., 2 of (+) type and other 2 of (-) type. Basidiospores are dispersed by wind and fall on the berberry plant and infect mainly the leaves. Pycnia (+ and – type) are produced on the upper epidermis of the leaflet by the (+) and (– )type basidiospores, respectively. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE After spermatisation between pycnospore and receptive hypha, and with the help of raindrop or insect, dikaryotic condition is established resulting into the formation of aecia and aeciospores development in different aecium are of the same type. After release from the barberry leaflet with the help of wind, it falls on the surface of wheat plant and after infection it produces uredosorus containing uredospores. Then uredospores infect different region of the same plant or the different plants and develop next crop of uredospores in the same season. This is the secondary cycle which may repeat several times in the growing season. At the end of the growing season i.e. during February to March, infection of uredospores takes place, but instead of developing uredosorus it develops teleutosorus containing teleutospores and thus complete the disease cycle. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Teleutospore is the thick- Each Basidiospores contain a Pycniospores are walled resting spore of haploid nucleus that is the produced in special cup- some fungi from which product of meiosis and like structures called the basidium arises. attached to the basidium by pycnia or pynidia. short spikes called sterigmata. Different type spores Aeciospores have two nuclei Uredospores are thin-walled and are typically seen in chain- spores produced by the uredium, like formations in the aecium. a stage in the life-cycle of rusts. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Loose Smut disease Loose smut of barley is caused by Ustilago nuda. but there are many strains of Ustilago which infect many different cereal crops in a similar manner. Ustilago tritici, causes loose smut of wheat. Systematic Position of Ustilago nuda: Kingdom- Fungi Division- Basidiomycota Class- Ustilaginomycetes Order- Ustilaginales Family- Ustilaginaceae Genus- Ustilago Species- nuda BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Symptoms: .The major symptom of loose smut is the "smutted" grain heads, which contain masses of black or brown spores where the grain would normally be. .The spores completely replace the grain head so that there is no grain to be harvested on infected plants. .The fungus causes infected plants to grow slightly taller and mature slightly sooner than the uninfected plants in the field. .Since it must infect through the open florets, this gives the fungus a competitive advantage by allowing it to fall down to the healthy plants and ensuring that the fungus has a little extra time to produce and disperse spores before the florets of the healthy plants open. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND CIRCULATED BY BANGAMOTI HANSDA, ASSISTANT PROFESSOR, DEPARTMENT OF BOTANY, NARAJOLE RAJ COLLEGE Disease Cycle of Loose smut The disease cycle of loose smut begins when teliospores are blown to open flowers and infect the ovary either through the stigma or directly through the ovary wall. There are multiple mating types for Ustilago spp. So infection will only occur if two compatible mating types are present in the same flower. After landing in an open floret, the teliospores give rise to basidiospores. Without dispersing to any alternate host plant, the basidiospores germinate right where they are. The hyphae of two compatible basidiospores then fuse to establish a dikarytic stage. After germination inside the ovary, the fungal mycelia invade the developing embryo in the seed. The fungus stays alive in the seed until the next growing season, when it is planted along with the seed. As the developing plant grows, the fungus grows with it. Once it's time for the flowers to form, teliospores are produced in place of the flowers and develop where the grain would be. BOATNY: SEM-II, PAPER-C 3T: MYCOLOGY AND PHYTOPATHOLOGY, UNIT 4: BASIDIOMYCOTA COMPILED AND