Nutrition in Fungi Key Points with PPT (Saprophytic, Parasitic, Symbiotic and Predator Fungi)

nutrition in fungi

Ø  Fungi are heterotrophic in nutrition

Ø  They are chlorophyll deficient plants and hence they cannot manufacture carbohydrates using carbon dioxide, water and sunlight

Ø  Fungi are with simple structural organization, thus they always depends on dead or living organic matter for their energy requirements

Ø  On the basis of mode of nutrition, fungi are classified into four groups:

(1). Saprophytes

(2). Parasites

(3). Symbionts

(4). Predacious fungi

saprophytic fungi example

Rhizopus (source wikipedia)

(1). Saprophytes

Ø  Saprophytic fungi obtain nutrition from dead organic matter

Ø  These fungi lives on dead organic matter or excreta of both plant and animal origin

Ø  Examples: Mucor, Rhizopus, Penicillium and Aspergillus

Ø  Vegetative hyphae of these fungi directly absorb food materials from organic matter

Ø  Saprophytic fungi may be of two types:-

(1). Ectophytic saprophytes: grown on the surface of organic matter

(2). Endophytic saprophytes: grown inside the organic matter

Ø  In some ectophytic fungi such as Rhizopus, special absorptive structures such as rhizoids are developed for the easy absorption of food materials

Ø  Saprophytic fungi produce exo-enzymes (enzymes which acts outside the cell)

Ø  These enzymes digest the complex organic matter in the substratum into simpler compounds to facilitate easy absorption by the hyphae

Learn more: Fungi- General Characteristics

stem rust of wheat

Rust Disease of Wheat by Puccinia

(2). Parasites

Ø  Parasitic fungi take food from other living plants or animals

Ø  The living organism on which the fungi parasitize are called host

Ø  Parasitic fungi are harmful to the host and they produce disease condition in host organisms

Ø  The relationship of host and parasite in pathology is known as parasitism

Ø  Parasitic fungi are of three types:-

(1). Obligate parasites: these fungi can live only as parasite on a living host

       Obligate parasites cannot live on dead organic matter

       Example: Puccinia which cause rust disease in several crop plants including wheat

(2). Facultative saprophytes: They are parasites, but they can also survive on dead organic matter in the absence of living host

       Example: Taphrina

disease caused by rhizopus in plants

Rhizopus infection in Jack-fruits (wikipedia)

(3). Facultative parasites: these fungi usually follow saprophytic mode of nutrition

               Under certain conditions, they parasitize suitable host plants

               Example: Fusarium and Pythium which cause soft rot disease in crop plants

Ø  On the basis of location of parasite in host organism, the parasites may be:

Endoparasite: parasite live inside the host tissue

Ectoparasite: parasite fungi which live on the outside surface of host

Ø  Parasitic fungi possess specialized absorptive structures called haustoria for the absorption of nutrients from the host cells

Ø  Haustoria are specialized hyphal modifications

Learn more: Hyphal Modifications in Fungi

Ø  Haustoria may be inter-cellular (occupy between two cells) in intra-cellular (occupy within the cell)

Ø  Size and shape of haustoria varies in different fungal groups

Ø  Haustoria may be round, knob like, club like or branched

fungal haustorium

Haustoria of Parasitic Fungus (source wikipedia)

(3). Symbionts

Ø  These fungi grow on or with other living organism but both of them are mutually benefited

Flavoparmelia caperata - lichen - Caperatflechte

Foliose Lichen (source wikipedia)

Ø  Lichens and mycorrhiza are examples

Ø  Lichens are the symbiotic association between algae and fungi

Ø  Here both fungi and algae are mutually benefited

Ø  Algae synthesize carbohydrates where as the fungi provides shelter for algae

Ø  Mycorrhizae are the symbiotic association between fungi and roots of some higher plants

Ø  Mycorrhizae helps in the absorption of nutrients by the host plant

what is ectomycorrhiza

Amanita Mycorrhiza (wikipedia)

Ø  Mycorrhiza may be ectophytic or endophytic

Ø  Ectophytic mycorrhiza are external mycorrhiza and they are confined to the outer region of the roots

Ø  Endophytic mycorrhiza are internal mycorrhiza and they are found deeply in the root cells

(4). Predacious fungi

Ø  They are animal capturing fungi (predators)

Ø  These types of fungi possess special hyphal traps called snares to tap and capture small animals such as nematodes and protozoa

Ø  They usually inhabit in the soil

Ø  They possess rapidly constricting hyphal traps which hold the captive for long time

Ø  They also have haustoria which directly inserted into the tissue of the prey

Ø  Some predacious fungi also produce sticky secretions for capturing nematodes

Ø  Examples of predator fungi: Arthrobotrys, Dactylella, Dactylaria

what are snares?

<< Back to BOTANY Lecture Notes

Mycology Short Notes

Get our Updates on Botany Lecture Notes in your E-mail Inbox
We will not spam your account…

Enter your e-mail address

You may also like…

@. Fungi: General Characteristics

@. Hyphal Modifications in Fungi

@. Botany Lecture Notes

@. Biology Lecture Notes

@. Biology Exams

@. Biology MCQ

@. Biology PPTs

@. Video Tutorials

Please Share for your Students, Colleagues, Friends and Relatives…

Posted in Lecture Notes, Mycology: Fungi and tagged , , , , .


Leave a Reply

Your email address will not be published. Required fields are marked *