TOPIC:KINGDOM-FUNGI BY DARADI GOSWAMI.pptx

The topic of the entire Kingdom Fungi is covered, including its general characteristics, reproduction methods, and classification.

1. Prepared by: DARADI GOSWAMI KINGDOM-FUNGI

2. INTRODUCTION Fungi -E ukaryotic, non-phototrophic living organisms with rigid cell walls that belong to the fungi kingdom.  Fungi are placed into a separate kingdom primarily due to their distinct characteristics and biological differences from plants, animals, and other organisms. Here are some key reasons why fungi have their own kingdom-

3. FUNGI Cell Structure : Fungi have cell walls made of chitin, unlike plants, which have cell walls made of cellulose. This structural difference is significant in classifying organisms. Nutrition : Fungi are heterotrophic, meaning they obtain nutrients by absorbing organic matter from their surroundings. They often decompose dead organisms or form symbiotic relationships to get their nutrients, whereas plants are autotrophic and produce their own food through photosynthesis. Reproduction : Fungi reproduce through both sexual and asexual means, with various unique mechanisms like spore production, which are different from the reproductive methods seen in plants and animals.

4. Growth and Development : The growth forms of fungi, such as hyphae (long, filamentous structures) and mycelium (a network of hyphae ), are distinct from the structures found in plants and animals. Genetics and Biochemistry : Molecular studies and genetic analyses have revealed significant differences between fungi and other kingdoms. For example, fungal genetics and biochemistry differ from those of plants and animals in various ways, supporting their classification into a separate kingdom. Ecological Roles : Fungi play unique ecological roles, such as decomposers, which are crucial for nutrient cycling in ecosystems. Their ecological functions are different from those of plants, animals, and other organisms, highlighting their distinctiveness. FUNGI

5. GENERAL CHARACTERISTICS OF FUNGI Cell Wall Composition : Fungi have cell walls made of chitin, a strong, flexible polysaccharide. Nutritional Mode : Fungi are heterotrophic and absorb nutrients from external sources. They can be saprophytic (decomposing dead organic matter), parasitic (feeding on living hosts), or mutualistic (engaging in symbiotic relationships). Structure : The basic structural unit of most fungi is the hypha , which is a thread-like filament. Hyphae form a network called mycelium, which constitutes the main body of the fungus. Some fungi also produce structures like mushrooms or puffballs for reproduction.

6. Reproduction : Fungi reproduce through both sexual and asexual means. Asexual reproduction often occurs via the production of spores or conidia, while sexual reproduction involves the fusion of specialized sexual structures and the formation of new spores. Spore Production : Fungi produce spores, which are reproductive cells capable of developing into a new organism. Spores can be dispersed by air, water, or animals, and they play a critical role in fungal reproduction and survival. Growth : Fungi grow by extending their hyphae , which allows them to spread out and explore their environment. This growth is often visible as mold or yeast colonies. GENERAL CHARACTERISTICS OF FUNGI

7. Diverse Habitats : Fungi can thrive in a wide range of environments, from soil and decaying matter to extreme conditions like high salinity or extreme temperatures. Lack of Chlorophyll : Unlike plants, fungi do not contain chlorophyll and do not perform photosynthesis. Instead, they rely on external sources of organic carbon. Metabolism : Fungi have a diverse range of metabolic processes, including the ability to break down complex organic materials, which makes them crucial decomposers in ecosystems. Symbiosis : Many fungi engage in symbiotic relationships with other organisms. Examples include mycorrhizae (associations with plant roots) and lichen (a mutualistic relationship between fungi and algae or cyanobacteria ). GENERAL CHARACTERISTICS OF FUNGI

8. CELL STRUCTURE OF FUNGI

9. CELL STRUCTURE OF FUNGI Cell Membrane : Composition : The cell membrane, or plasma membrane, lies just inside the cell wall and is composed of a lipid bilayer with embedded proteins. It controls the movement of substances in and out of the cell. Function : It regulates nutrient uptake, waste removal, and communication with the environment.

10. CELL STRUCTURE OF FUNGI Cell Wall : Composition : Fungal cell walls are primarily composed of chitin, a long-chain polymer of N- acetylglucosamine , which provides structural support and rigidity. This is different from plant cell walls, which are made of cellulose. Function : The cell wall provides protection, maintains cell shape, and contributes to the fungal body's overall structural integrity.

11. Cytoplasm: Contents : The cytoplasm contains various organelles, including mitochondria, ribosomes , and endoplasmic reticulum. It is the site of many metabolic processes. Function : It supports cellular functions and provides a medium for biochemical reactions. CELL STRUCTURE OF FUNGI

12. Nucleus : Structure : The nucleus is usually enclosed by a double membrane and contains the cell's genetic material (DNA). Function : It controls gene expression and cell division. CELL STRUCTURE OF FUNGI

13. Mitochondria : Structure : Mitochondria are membrane-bound organelles with their own DNA. Function : They are responsible for producing ATP through cellular respiration, which provides energy for various cellular processes. CELL STRUCTURE OF FUNGI

14. Vacuoles : Structure : Vacuoles are membrane-bound organelles that can vary in size. Function : In fungi, vacuoles store nutrients, waste products, and help maintain turgor pressure. They can also play roles in detoxification and pH regulation. CELL STRUCTURE OF FUNGI

15. Hyphae and Mycelium : Hyphae : These are the thread-like, branching filaments that make up the body of most fungi. They grow at their tips and spread out to form a network. Mycelium : A collective network of hyphae that constitutes the main vegetative structure of the fungus. Mycelium is responsible for nutrient absorption. CELL STRUCTURE OF FUNGI

16. Septate and Coenocytic Hyphae : Septate Hyphae : These hyphae are divided into cells by internal cross-walls called septa. Each cell contains one or more nuclei. Coenocytic Hyphae : These hyphae lack septa and have a continuous cytoplasm with multiple nuclei distributed throughout. CELL STRUCTURE OF FUNGI

17. Reproductive Structures : Spores : Fungi produce spores, which are reproductive cells capable of developing into a new organism. Spores are often produced in specialized structures like sporangia or conidiophores. Plasmodesmata : Presence : Some fungi have plasmodesmata , which are channels that allow for the exchange of materials between adjacent cells CELL STRUCTURE OF FUNGI

18. REPRODUCTION IN FUNGI Fungi have diverse and often complex methods of reproduction, involving both sexual and asexual processes. Asexual Reproduction Spore Production : Conidia : Many fungi produce asexual spores called conidia, which are not enclosed in a sac. Conidia are often produced on specialized structures called conidiophores. Sporangia : Some fungi produce spores within a sac-like structure called a sporangium. When the sporangium bursts, the spores are released into the environment. Chlamydospores : These are thick-walled, dormant spores that can survive unfavorable conditions and germinate when conditions become favorable.

19. Budding : Process : In yeast fungi, a form of asexual reproduction called budding occurs. A new organism develops from an outgrowth or bud on the parent organism. The bud eventually pinches off to become a separate individual. Fragmentation : Process : Some fungi reproduce asexually by breaking apart. Each fragment of the fungal mycelium can grow into a new individual, provided it has the necessary nutrients and conditions. REPRODUCTION IN FUNGI

20. Sexual Reproduction Plasmogamy : Process : Sexual reproduction often begins with the fusion of two sexually compatible hyphae from different mating types. This fusion is called plasmogamy , where the cytoplasm of the two cells merges, but their nuclei remain separate. Karyogamy : Process : Following plasmogamy , the nuclei from the two parent cells eventually fuse in a process called karyogamy . This results in the formation of a diploid nucleus. Meiosis : Process : The diploid nucleus undergoes meiosis to produce haploid spores. These spores are genetically diverse due to the recombination of genetic material during meiosis. REPRODUCTION IN FUNGI

21. Formation of Sexual Structures : Ascomycetes : In ascomycetes (sac fungi), sexual reproduction involves the formation of asci (sac-like structures) that contain the ascospores . The asci are typically formed within a fruiting body called an ascocarp . Basidiomycetes : In basidiomycetes (club fungi), sexual reproduction involves the formation of basidia (club-shaped structures) that produce basidiospores . Basidia are usually found on the gills or pores of the mushroom cap. Zygomycetes : In zygomycetes (conjugated fungi), sexual reproduction involves the fusion of specialized hyphae to form a zygospore . This zygospore eventually undergoes meiosis to produce haploid spores. REPRODUCTION IN FUNGI

22. Spore Dispersal : Process : Both asexual and sexual spores are dispersed into the environment. Spores can be spread by wind, water, or animals, and they germinate when they land in suitable conditions. Fungi utilize both asexual and sexual reproduction to propagate and adapt to their environments. Asexual reproduction allows for rapid colonization and persistence, while sexual reproduction promotes genetic diversity and adaptability. Each method of reproduction involves specialized structures and processes, highlighting the complex and varied nature of fungal biology. REPRODUCTION IN FUNGI

23. REPRODUCTION IN FUNGI

24. ECONOMIC IMORTANCE OF FUNGI 1. Medicine Antibiotics : Penicillium chrysogenum produces penicillin, the first widely used antibiotic, revolutionizing medicine by treating bacterial infections. Antifungals : Fungi like Aspergillus and Penicillium are sources of antifungal drugs used to treat fungal infections in humans. Immunosuppressants : Tolypocladium inflatum produces cyclosporine, an immunosuppressant used to prevent organ rejection in transplants.

25. 2. Food Industry Edible Fungi : Agaricus bisporus (button mushroom), Pleurotus ostreatus (oyster mushroom), and Lentinula edodes (shiitake mushroom) are cultivated for consumption, providing essential nutrients and flavors. Fermentation : Yeasts like Saccharomyces cerevisiae are crucial for baking, brewing, and winemaking, facilitating the production of bread, beer, wine, and spirits. Cheese Production : Molds such as Penicillium roqueforti and Penicillium camemberti are used in the production of blue cheeses and camembert, respectively. ECONOMIC IMORTANCE OF FUNGI

26. 3. Agriculture Biopesticides : Some fungi, like Beauveria bassiana , are used as biological control agents against pests, reducing the need for chemical pesticides. Soil Health : Mycorrhizal fungi, such as those in the genus Glomus , form symbiotic relationships with plant roots, enhancing nutrient uptake and improving soil fertility. ECONOMIC IMORTANCE OF FUNGI

27. 4. Biotechnology Enzyme Production : Fungi produce a variety of enzymes used in industrial processes, including cellulases for biofuel production and proteases for detergent manufacturing. Genetic Engineering : Fungi are used as model organisms in genetic research and biotechnology, facilitating the development of new products and processes. IMORTANCE OF FUNGI

28. 5. Environmental Applications Bioremediation : Fungi such as Aspergillus niger and Phanerochaete chrysosporium are employed to degrade environmental pollutants, including pesticides and hydrocarbons, aiding in the cleanup of contaminated sites. Mycoremediation : Certain fungi are used to degrade or transform toxic substances in the environment, contributing to pollution control and soil restoration. IMORTANCE OF FUNGI

29. 6.Research and Development Model Organisms : Fungi such as Saccharomyces cerevisiae (baker’s yeast) and Neurospora crassa are used in genetic and biochemical research, helping scientists understand fundamental biological processes and develop new technologies. IMORTANCE OF FUNGI

30. CLASSIFICATION OF FUNGI

31. DIFFERENCE -

32. Examples of fungi

33. PHYCOMYCETES Phycomycetes are a class of fungi-like organisms within the phylum Oomycota (often referred to as water molds or oomycetes) Characteristics of Phycomycetes Cell Wall Composition : Cellulose : The cell walls of phycomycetes are primarily composed of cellulose, distinguishing them from the true fungi ( Eumycota ), which have cell walls made of chitin. Body Structure : Hyphal Structure : Phycomycetes typically have coenocytic (non- septate ) hyphae . These hyphae are multinucleate and lack the cross-walls (septa) found in many other fungi.

34. Habitat : Aquatic and Moist Environments : Phycomycetes are commonly found in aquatic environments, including freshwater and marine habitats, as well as in moist terrestrial environments. Nutrition : Saprophytic and Parasitic : Many phycomycetes are saprophytic, decompose dead organic matter. Others are parasitic, attacking plants, algae, or other organisms. Reproductive Structures : Specialized Structures : Phycomycetes produce specialized reproductive structures for both sexual and asexual reproduction, which are adapted to their aquatic or moist habitats.

35. Reproduction in Phycomycetes 1. Asexual Reproduction Sporangia : Asexual reproduction in phycomycetes often involves the formation of sporangia, which are sac-like structures that produce and release asexual spores ( sporangiospores ). The sporangia can be borne on specialized hyphal structures. Sporangiospores : The spores produced within the sporangia are typically motile (in water molds) or non-motile (depending on the species) and are released into the environment. They can germinate to form new hyphae and mycelium. Zoospores : In some phycomycetes , the asexual spores are zoospores, which are motile and have one or two flagella that help them swim through water. They can encyst and germinate to form new fungal colonies.

36. 2. Sexual Reproduction Oogamy : Sexual reproduction in phycomycetes involves a process called oogamy , where two distinct types of sexual structures, oogonia (female) and antheridia (male), come together. Oogonia and Antheridia : The oogonium is a swollen, spherical structure that contains one or more eggs. The antheridium is a specialized structure that produces male gametes ( spermatia ) that fertilize the eggs in the oogonium . Oospore Formation : After fertilization, the zygote develops into an oospore , which is a thick-walled, resistant structure. The oospore can survive unfavorable conditions and germinate when conditions improve. Germination : When the oospore germinates, it typically produces a new hyphal structure that grows and eventually forms sporangia, completing the reproductive cycle.

37. Phycomycetes , as part of the Oomycota , exhibit unique characteristics such as cellulose-based cell walls, coenocytic hyphae, and specialized reproductive structures adapted to aquatic or moist environments. Their reproduction includes both asexual methods (via sporangia and zoospores) and sexual methods (involving oogonia and antheridia). These characteristics and reproductive strategies help them thrive in their diverse habitats.

38. ASCOMYCETES Ascomycetes (or Ascomycota ) are a large and diverse group of fungi known for their unique reproductive structures and wide range of ecological roles. Characteristics of Ascomycetes Cell Wall Composition : Chitin : Like other true fungi ( Eumycota ), ascomycetes have cell walls composed of chitin, a strong, flexible polysaccharide. Body Structure : Hyphae : Ascomycetes typically have septate (partitioned) hyphae , which are divided by cross-walls (septa) that contain one or more nuclei. This allows for compartmentalization within the fungal mycelium. Reproductive Structures : Asci : The defining feature of ascomycetes is the ascus , a sac-like structure where sexual spores are produced. The asci are often contained within a larger fruiting body called an ascocarp .

39. Habitats : Diverse Environments : Ascomycetes inhabit a wide range of environments, including soil, decaying organic matter, plants, animals, and even extreme habitats. Some form symbiotic relationships, such as lichens and mycorrhizae . Nutrition : Saprophytic, Parasitic, and Mutualistic : Ascomycetes can be saprophytic (decomposing dead matter), parasitic (attacking living hosts), or mutualistic (forming beneficial partnerships with other organisms). ASCOMYCETES

40. Reproduction in Ascomycetes 1. Asexual Reproduction Conidia : Asexual reproduction often involves the production of conidia, which are non-motile, asexual spores produced on specialized hyphal structures called conidiophores. Conidia can be dispersed by wind, water, or animals and germinate to form new mycelium. Blastoconidia : In some yeasts within the Ascomycetes , asexual reproduction occurs through budding, where a new organism forms as a bud from the parent cell and eventually separates. ASCOMYCETES

41. 2. Sexual Reproduction Ascocarp Formation : Sexual reproduction involves the formation of a complex fruiting body called the ascocarp . The ascocarp houses the asci , where sexual spores are produced. Different types of ascocarps include apothecia (cup-shaped), perithecia (flask-shaped), and cleistothecia (closed). Ascus Formation : Within the ascocarp , specialized cells called asci develop. Each ascus contains eight ascospores , which are produced following meiosis and mitosis. ASCOMYCETES

42. 2. Sexual Reproduction Karyogamy and Meiosis : Sexual reproduction begins with the fusion of two compatible hyphae, leading to the formation of a dikaryotic cell (with two distinct nuclei). The nuclei eventually fuse ( karyogamy ), forming a diploid zygote. This zygote undergoes meiosis to produce haploid ascospores . Spore Release : The ascospores are released from the asci into the environment. Upon germination, they grow into new hyphae and mycelium, continuing the life cycle. ASCOMYCETES

43. Ascomycetes , or Ascomycota , are characterized by their chitin-rich cell walls, septate hyphae , and the production of sexual spores within asci . They exhibit a wide range of ecological roles and can reproduce both asexually (via conidia and budding) and sexually (through the formation of asci and ascocarps ).

44. Ecological Role of Ascomycetes 1 Decomposers : Example : Aspergillus niger - This mold breaks down organic materials and contributes to the decomposition process in soil and decaying matter. 2 Symbiotic Relationships : Lichens : Example : Cladonia rangiferina (reindeer lichen) - Forms a mutualistic relationship with green algae or cyanobacteria , thriving in arctic and subarctic regions.

45. Ecological Role of Ascomycetes 3 Mycorrhizae : Example : Tuber melanosporum (black truffle) - Associates with oak and hazelnut roots, enhancing nutrient uptake for the plant while obtaining carbohydrates. 4 Pathogens : Plant Pathogens : Example : Erysiphe graminis (causes powdery mildew in wheat) - Affects crops and natural vegetation, influencing plant health.

46. 5 Food Source : Example : Morchella esculenta (morel) - An edible fungus highly prized for its culinary uses and contributes to diverse diets . 6 Bioindicators : Example : Lecanora conizaeoides - Sensitive to air pollution, used to monitor atmospheric quality and environmental changes. Ecological Role of Ascomycetes

47. 7 Bioremediation : Example : Aspergillus flavus - Known for its ability to degrade environmental pollutants and is used in bioremediation processes. 8 Nutrient Cycling : Example : Penicillium chrysogenum - Contributes to nutrient cycling by decomposing organic matter and releasing nutrients back into the soil. Ecological Role of Ascomycetes

48. BASIDIOMYCETES Basidiomycetes ( Basidiomycota ) are a diverse and ecologically significant group of fungi known for their distinctive reproductive structures and roles in various environments. Here’s an overview of their characteristics and reproduction : Characteristics of Basidiomycetes Cell Wall Composition : Chitin : Like other true fungi, basidiomycetes have cell walls composed of chitin, which provides structural support and rigidity .

49. BASIDOMYCETES Characteristics of Basidiomycetes Body Structure : Hyphae : Basidiomycetes typically have septate (partitioned) hyphae , which are divided by cross-walls called septa that contain one or more nuclei. This allows for compartmentalization within the mycelium. Fruiting Bodies : Basidiocarps : They produce elaborate fruiting bodies known as basidiocarps , which include mushrooms, toadstools, and shelf fungi. These structures are involved in the production and release of sexual spores.

50. Reproductive Structures : Basidia : The defining feature of basidiomycetes is the basidium , a club-shaped cell where sexual spores are produced. Each basidium typically bears four basidiospores . Habitats : Diverse Environments : Basidiomycetes inhabit a wide range of environments, including forests, grasslands, and decaying wood. They play key roles in decomposing organic matter and forming mycorrhizal associations . BASIDOMYCETES

51. Nutrition : Saprophytic, Parasitic, and Mutualistic : They can be saprophytic (decomposing dead organic matter), parasitic (attacking plants or other organisms), or mutualistic (forming beneficial partnerships with plants). BASIDIOMYCETES

52. Reproduction in Basidiomycetes 1. Asexual Reproduction Vegetative Propagation : While less common, some basidiomycetes can reproduce asexually through vegetative means such as fragmentation, where pieces of mycelium can grow into new individuals. Asexual Spores : Some species produce asexual spores called conidia or chlamydospores , although this is less characteristic compared to their sexual reproduction. BASIDIOMYCETES

53. 2. Sexual Reproduction Plasmogamy : Sexual reproduction begins with the fusion of two compatible hyphae from different mating types. This fusion results in the formation of a dikaryotic mycelium, where each cell contains two separate nuclei. Basidium Formation : The dikaryotic mycelium develops into a basidiocarp (fruiting body). Within the basidiocarp , specialized cells called basidia form . BASIDIOMYCETES

54. 2. Sexual Reproduction Karyogamy and Meiosis : In the basidium , the two nuclei fuse ( karyogamy ) to form a diploid zygote. This zygote undergoes meiosis, producing four haploid basidiospores . Basidiospores : The basidiospores are released from the basidia into the environment. They are often dispersed by wind, water, or animals and can germinate to form new mycelium. Germination : Upon landing in a suitable environment, basidiospores germinate and grow into new hyphae , continuing the life cycle. BASIDIOMYCETES

55. Basidiomycetes , or Basidiomycota , are distinguished by their chitinous cell walls, septate hyphae, and complex fruiting bodies called basidiocarps . Their sexual reproduction involves the formation of basidia that produce basidiospores , crucial for dispersal and survival. Basidiomycetes play essential roles as decomposers, pathogens, and mutualistic partners in various ecosystems. BASIDIOMYCETES

56. DEUTEROMYCETES Deuteromycetes (also known as Deuteromycota or imperfect fungi ) are a diverse group of fungi that are classified based on their asexual reproductive structures Characteristics of Deuteromycetes Asexual Reproduction : Lack of Sexual Stage : Deuteromycetes are primarily characterized by the absence of a known sexual reproductive stage. They are often referred to as "imperfect fungi" because their sexual reproductive structures have not been observed or described .

57. DEUTEROMYCETES Characteristics of Deuteromycetes Asexual Reproductive Structures : Conidia : Most deuteromycetes reproduce asexually through the production of conidia, which are non-motile, asexual spores. These conidia are produced on specialized structures called conidiophores. Conidiophores : The conidiophores are specialized hyphal structures that bear the conidia. They can be simple or branched, and the arrangement of conidia can vary widely among species.

58. Hyphal Structure : Septate or Coenocytic : Deuteromycetes may have septate (partitioned) or coenocytic (non- septate ) hyphae . Septate hyphae have cross-walls that compartmentalize the fungal cells, while coenocytic hyphae lack these partitions . DEUTEROMYCETES

59. Habitats : Diverse Environments : Deuteromycetes are found in a wide range of habitats, including soil, decaying organic matter, plant surfaces, and as pathogens of plants and animals. Nutrition : Saprophytic, Parasitic, and Mutualistic : They can be saprophytic (decomposing dead organic matter), parasitic (attacking living hosts), or mutualistic (forming beneficial relationships with other organisms). DEUTEROMYCETES

60. R eproduction in Deuteromycetes 1. Asexual Reproduction Conidial Development : Conidia can develop in various ways: Blastospores : Produced by budding from the parent cell (similar to budding in yeasts). Chlamydospores : Thick-walled, resistant spores formed in certain conditions that can survive harsh environments and germinate when conditions improve. DEUTEROMYCETES

61. R eproduction in Deuteromycetes 1. Asexual Reproduction Conidia Formation : The primary mode of reproduction in deuteromycetes is asexual, involving the production of conidia. Conidia are formed on conidiophores and are released into the environment where they can germinate to form new fungal colonies . DEUTEROMYCETES

62. 2. Sexual Reproduction Unknown or Undiscovered : In many deuteromycetes , sexual reproduction has not been observed, or the fungi are known only from their asexual reproductive stages. When sexual reproduction does occur, it may not be well-documented or understood, often leading to reclassification once sexual stages are discovered. Taxonomic Reclassification : Many fungi previously classified as deuteromycetes have been reclassified into other fungal groups (such as Ascomycetes or Basidiomycetes ) once their sexual reproductive stages were observed and characterized. DEUTEROMYCETES

63. Deuteromycetes are defined by their asexual reproduction through conidia and conidiophores, with their sexual reproduction often unknown or undiscovered. They occupy diverse environments and include important saprophytic, parasitic, and mutualistic species. Due to the lack of observed sexual stages, many fungi in this group have been reclassified into other fungal phyla as more information about their reproductive biology becomes available. DEUTEROMYCETES

64. SYMBIOTIC RELATIONSHIP Fungi engage in a variety of symbiotic relationships with other organisms, including plants, algae, bacteria, and animals. These relationships can be mutualistic , commensalistic , or parasitic, and they play crucial roles in ecosystem. 1. Mutualistic Symbiosis Mutualism is a type of symbiotic relationship where both partners benefit from the interaction. In fungi, mutualistic relationships are often seen in mycorrhizae and lichens. Mycorrhizae Definition : Mycorrhizae are symbiotic associations between fungi and plant roots. The fungus enhances nutrient and water uptake for the plant, while the plant provides carbohydrates and other organic compounds to the fungus

65. Types of Mycorrhizae : Ectomycorrhizae : The fungal hyphae form a sheath around the root and penetrate between the root cells but do not enter the cells. Example : Boletus edulis (king bolete ) - Forms ectomycorrhizal associations with trees like oak and pine. Endomycorrhizae : The fungal hyphae penetrate the root cells and form structures like arbuscules or vesicles inside the cells. Example : Glomus species - Commonly associated with many plant species, including crops like maize and wheat.

66. LICHENS Lichens Definition : Lichens are mutualistic partnerships between fungi and photosynthetic organisms (algae or cyanobacteria ). The fungus provides a protective environment and access to nutrients, while the photosynthetic partner produces organic compounds through photosynthesis. Examples : Cladonia rangiferina (reindeer lichen) - Associates with green algae or cyanobacteria , thriving in arctic and subarctic environments. Xanthoria parietina - A common lichen that partners with green algae, found on rocks, tree bark, and buildings.

67. 2. Commensalistic Symbiosis Commensalism is a type of symbiotic relationship where one partner benefits while the other is neither helped nor harmed. Fungal Commensalism Definition : In these relationships, fungi live on or within other organisms without causing harm or providing a significant benefit to the host. Examples : Penicillium species - Some species of this genus live on decaying organic matter or in soil without affecting their hosts significantly. Aspergillus species - Commonly found in soil and on decaying plant material; can also colonize indoor environments without directly harming human hosts.

68. 3. Parasitic Symbiosis Parasitism is a type of symbiotic relationship where one partner benefits at the expense of the other. In fungi, parasitism can be quite harmful to the host. Plant Pathogens Definition : Parasitic fungi that infect and damage plants, often causing diseases and affecting agricultural productivity. Examples : Puccinia graminis (wheat rust) - Causes rust disease in wheat, leading to significant crop losses. Fusarium oxysporum - Causes wilt diseases in various crops, including tomatoes and bananas.

69. Animal Pathogens Definition : Parasitic fungi that infect animals, including humans, causing diseases and health issues. Examples : Candida albicans - Causes opportunistic infections like thrush and candidiasis in humans. Batrachochytrium dendrobatidis ( chytrid fungus) - Infects amphibians, contributing to declines in amphibian populations worldwide.

70. Fungi participate in a range of symbiotic relationships, including mutualistic partnerships ( mycorrhizae and lichens), commensalistic interactions (some environmental fungi), and parasitic relationships (plant and animal pathogens). These interactions play essential roles in ecosystems, agriculture, and human health.