General characteristics of fungi

General characteristics of fungi

1. General characteristics of fungi Sankrita Gaonkar Assistant Professor in Botany [email protected]

2. Contents General characteristics of fungi References

3. General characters of fungi: Thallus Body of fungus Vegetative phase of fungus Consists of tubular filaments called hyphae (sing. Hypha) Mass of hyphae – mycelium (pl. mycelia) A) Unicellular thallus B) Filamentous thallus

4. A) Unicellular thallus Chytrids – thallus is spherical and single-celled – becomes reproductive unit (asexual or sexual cells) during reproduction  Holocarpic Plasmodiophora – vegetative phase – naked, multinucleate, amoeboid mass of protoplasm – Plasmodium (cleaves to form resting spores). Yeast cells

5. B) Filamentous thallus Originates through germination of spore Spore on germination produces hypha – forms fluffy thallus of long filaments – hyphae At maturity, some hyphae extend into air and form reproductive bodies Hyphae spread on substratum – Eucarpic Vegetative body formed collectively by hyphae - mycelium Mycelium

6. Types of mycelia i ) Aseptate mycelium Lack internal partitions Multinucleate - coenocytic ii) Septate mycelium Develop internal partitions – septa Uninucleate or multinucleate Septate mycelium Aseptate mycelium

7. Modifications of hyphae i ) Plectenchyma – false tissue of hyphal aggregation a) Prosenchyma – loosely woven tissue of hyphae b) Pseudoparenchyma – compact mass of interwoven hyphae formed during fructification ii) Rhizomorph – root-like aggregation of somatic hyphae iii) Sclerotium – compact globose or elongated structure formed by hyphal aggregation Rhizomorph

8. iv) Stromata (sing. stroma) – fungal tissue forming reproductive structures v) Pseudosclerotium – sclerotia-like bodies formed at the base of fruiting bodies vi) Appressorium – swollen structure of germtube vii) Haustorium – intracellular absorbing structures

9. Modes of nutrition Saprophytes or saprobes – absorb nutrients through cell membrane from substratum (dead organic matter – animal or plant) Parasites – live in or on living body of a plant or animal and absorb nutrients through cell walls from host tissue. Eg. Rusts, smuts Reproduction – vegetative, asexual and sexual Infection by fungal parasite Saprophytic fungi

10. References Vashishta B.R., Sinha A.K. and Singh V.P. 2012. Botany for degree students: Algae. S. Chand & company ltd.