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Phylum:ascomycota • General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell wall contain large amount of chitin and less cellulose. 4.Cell wall contain large amount of chitin and less cellulose. 5. Harmful or parasities,causing several diseases to plantand human Saprophytes and may produce useful enzyemes and vitamins.

Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

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Page 1: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Phylum:ascomycota• General characters:1.Mycelium is septated and branched except in yeasts

(unicellular).

2.Complete absence of flagellated cells.

3.Cell wall contain large amount of chitin and less cellulose.

4.Cell wall contain large amount of chitin and less cellulose.

5. Harmful or parasities,causing several diseases to plantand human

Saprophytes and may produce useful enzyemes and vitamins.

Page 2: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

6. Asexual reproduction bu non motile conidia,which are produced on a specialized hypae called conidiophore.

7. Sexual reproduction produse ascospores in ascus(sac like structure) usually 8 spores.

Page 3: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

• Ascocarp:

More than one ascus or even one may enclosed in a fruiting body called ascocarp which may be :

Cleistothecium perithecium apothecium

Cleistothecium:

It is globose ,which has no natural openinig the cleistothecium wall may not covered with out growths

(appendages).

The asci may be arranged in hymenial layer or scatter

Asci are liberated by disintegration of the cleistothecial wall.

Page 4: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

• perithecium:

It is a flask shaped ascocar with an apical opening(ostiole).

The asci and paraphysis are arranged in a hyminial layer, ascospores libareted from the ostiole.

• apothecium:

It is a cup or saucer shaped ascocarp the asci and paraphsis ara arranged on the upper surface in a hymenial layer

Page 5: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Ascus formation

Page 6: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell
Page 7: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Subclass:protoascomycetes.Order: Endomycetales.

Family: Saccharomycetaceae.Saccharomyces cervisae.

• Vegetative structure and economic importance: yeasts are unicellular organisms, oval or spherical shaped,

live in colonies with white or yellow, and they are dimorphic. Dimorphism:

Is the ability of an organism to grow either unicellular or filamentous according to surrounding condition.

Ex:

Yeast at 370 c grow as unicellular.

at 240 c grow as mycelia

• Saccharomyces has avery important role in industries such as fermentation beaking production of vitamins and alchols.

Page 8: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Reproduction:1. budding:

• At favorable conditions (food is abundant) the nucleus of the yeast cell divides mitotically and a bud is formed from the wall of mother cell.

• Then one nucleus passes into this bud with a part of the cytoplasm then this bud separated from the mother cell to give daughter cell.

• Some times the bud itself may give another bud and the bud do not detached from the mother cells resulting in the fromation of

• Achain of bud called pseudomycelium.

Page 9: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

• fission: Parent cell elongates and its nucleus divides to produce

two daughter nuclei , then a wall is formed in the middle of the cell from two new cell.

Page 10: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

sexual reproduction• It takes place when food is exhausted ,it occurs by conjugation

between two vegetative cells the process is called hologamy ,this result in the formation of diploid zygot cell which function directly as an ascus and produce ascospores.

• 1-Haplopiontic life cycle. 2-diplobiontic life cycle. 3- haplodiplobiontic life cycle.

• Candid albicans is ahuman pathogen live in mouth, vagina and cause in young candidomycosis which may treared by amphotrosin c.

Page 11: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

• Subclass: Euascomycetes• Series: Plectomycetes

Order: Asergillales Order: Erysiphales

(Asci are scattered) family: Erysiphaceae

Family: Aspergillaceae

Ex: Aspergillus

Penicillium

)asci are arranged(

Page 12: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Aspergillus• *Aspergillus is a widely distrisbuted genus, most are

saprophytes on dead organic materials(fruits,jams ,leather, wood,……..) on orange, aspergillus form blue mould.

• On otherhand some species are parasites.• *A.flavus,A.fumigtus and A.niger cause diseases to human and

animals known asperilloses also they may cause disease for human ear called otomycosis.

• A.flavus produce mycotoxins.• A. fumigatus give fumes which may contaminate the

enviroment and cause respiratory tract infections of human.• A.niger is very important for industry it produce about (18-

19)enzymes including: cellulases xylanases amaylases pectinases inulinases phylase.

Page 13: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

vegetative structure:• The vegetative structure of Aspergillus is

branched and septated mycelia which may:

Substarte mycelium:

Responsible for fixation and nutrient up take.

Aerial mycelium:

Appeare above and carrying reproductive organs.

Page 14: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Asexual reproduction:• It takes place by means of conidia ,which are

formed in chains externally on conidiophores.1. When asexual reproduction takes place a certain cell of the

hyphae become larger and thick walled(foot cell).

2. From each foot cell a vertical, non-septated conidiophore arise each conidiophore ends with a vesicle.

3. A large number of nuclei and cytoplasm migrate into the vesicle.

4. From each vesicle a tubular outgrowths are produced(sterigmata).

(sterigmata may be used in identification of Aspergillus).

5. From the tips of sterigmata a chain of conidia are formed.

Page 15: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Penicillium• Pencicillium is a saprophytic fungus known as(blue or

green mould),it live on several organic substrates(fruits, vegetables,bread,……………….).

• Vegetative mycelium is branched and septated.

• Some species such as P. chrysogenum produce the antibiotic pencillin(break bonds between peptidoglycan in the cell wall of G+ve bacteria).

 • Conidiophores are spetated and branched.

Page 16: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Order: Erysiphales Family: Erysiphaceae

• members of this family are :• Obligate parasites,cause powdery mildew disease.• Produce their asci arranged on hymenial layer inside a

cleistothecium.• Depending on: The aggregation of conidia on

conidiophores.

Number of asci inside the cleistothecium.

Type of appendages.

Page 17: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

*the order Erysiphales is classified as follow

Family:Erysiphales

Subfamily:phyllactinae sub family:Erysipheae

*conidia

Are solitary

Phyllactinea leivellula

Conidia more one contain more than one ascus appendages are normal myceloid

Ascus ,appendages with

Bulbous base and pointed tips

Page 18: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

• sub family:Erysipheae

Erysiphe uncinulla

More than One ascus. More than one ascus

Normal appendges curved appendeges

Sphaerotheca

have one ascus

normal appendages

Page 19: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Subclass:EuascomycetesSeries:pyrenomycetesFamily:clavisiptaceae.

• This group of fungi profuce their ascus in a perithecium.

• Members of this fungi are parasites on graminae and cause ergot disease.

• The infected grains contain atoxic substance called ergotamine

• This substance has avascoconstrictor effect on the blood vessels and may cause hair falling.

Page 20: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

• This fungi produce asci in an open ascocarp(apothecium).• The apothecium is cup shaped so these fungi may known as

cup fungi.• The asci are arranged on a hymenial layer.

order:Pezizales

Family:Pezizaceae

Peziza sclerotinia morchella

Cup fungi cause rot of onion sponge mushroom

Saprophytes on animal

dungs. saprophytes grow on

And decaying wood cluster in soil rich in

Form large apothecium. Organic substances

Subclass:Euascomycetes Series:Discomycetes

Page 21: Phylum:ascomycota General characters: 1.Mycelium is septated and branched except in yeasts (unicellular). 2.Complete absence of flagellated cells. 3.Cell

Subclass:EuascomyctesSeries:Loculoascomycetes

• This group of fungi are form their asci in ascostroma .

• The ascus has two walls so it called bitunicate ascus

• The inner called endotunica extensible and thin

• The outer called exotunica inextensible and thick