Division: Mastigomycota

for more on the Plasmodiophora refer back to the ppt

Mastigomycota Characteristics

1. produce both uniflagellate or biflagellate zoospores

2. whiplash or tinsel flagellum

3. mostly aquatic and/or terrestrial

4. filaminentous and have coenonytic mycelium

5. unicellular form show pseudosepta

6. saprophytes or parasites

what are pseudosepta

false cross walls

all mastigomycota produce motile flagellate zoospores during

asexual reproduction

Sexual reproduction for mastigocycota is

isogamy or heterogamy and Oospore

Division : Mastigomycota is divided into

Haplomastigomycotina and Diplomastigocotina

Classification of Haplomastigomycotina

1. Chytridiomycetes

2. Hyphochytrimycetes

3. Plasmodiphoromyctes

Hyphochytrimycetes

anteriorly uniflagellate, aquatic fungi whose thallus is holocarpic ,and their vegatative systems is rhizoidal or hypa-like with intercalary swellings

Plasmodiphoromycetes

known as endo-parasitic slim molds. they are obligate parasites of freshwater algae, aquatic fungi, and higher plants. somatic body consists of necked holocarpic plasmodium

Chytridiomycetes

posteriorly uniflagellate zoospores they occur as saprobes on plants and animals remain in water while other members occur as parasites on algae and aquatic animals

classification of sub division : Chytridiomycetes

1. Chytridiales

2. Harpochytridiales

3. Blastchytridiales

4. Monoblepharidales

Order : Chytridiales

1. live as parasites or saprophytes

2. found in soil or aquatic environments

3. grow internally in algae or water mold

4. thallus is holocarpic or eucarpic

5. cell wal made of chitin

6. zoospores are spherical, posteriorly uniflagellate, and the flagellum is whiplash type

Sexual reproduction of Order : Chytridiales

by motile gametes released from gametangia

Synchytrium endobioticum

1. about 200 species worldwide

2. their vegetative consists of minute endobiotic holocarpic thallus.

3. do not develop any mycelium

4. produce summer sporangia haploid and winter sporangia diploid

5. zoospores attack the tubers

summer sporangia haploid

thin walls

winter sporangia diploid

thick walls

Reproduction in Synchytrium

both sexually and asexually , and the thallus transforms into holocarpic

Synchytrium endobioticum division

Mastigomycota

Synchytrium endobioticum Subdivison

Haplomastigomycotina

Synchytrium endobioticum Class

Chrytridiomycetes

Synchytrium endobioticum Order

Chytridiales

Synchytrium endobioticum Family

Synchytriaceae

what cause wart disease of potato

Synchytrium endobioticum

Pathology Synchytrium endobioticum

1. disease of potato

2. quarantine in effect in many countries to limit introduction

3. Biotrophic pathogen

4. causes hypertrophy of host

5. motile spores can function as zoospores

Synchytrium endobioticum has two different sporangia

1. winter sporangia - long lived stages

2. summer sporangia - short lived

Biotrophic pathogen

a lot of plant-pathogenic fungi establish a long-term feeding relationship with the living cells of their hosts, rather than killing the host cell as part of the infection proces.

Sexual Reproduction

2n

Asexual Reproduction

1n

why do zoospores migrate in soil water for a limited distance (50nm)

because they are short-lived and must encyst and infect susceptible host tissue within 1-2hr after their formation

After infection by zoospores

host cells enlarge and haploid sori form inside the host cells while neighboring hots cells begin to proliferate , resulting in the characteristics.

each sours contain

one to nine summer sporangia

rapidly repeating secondary disease cycles results in

an extensive invasion of host cells and rapid onset of gall formation

young galls

a nutrients sink and expand rapidly at the expense of other plant tissue

Favorable conditions of Synchytrium endobioticum

1. warm temperatures with enough humidity

2. winter sporangia can remain viable for up to 20-30 years

3. survive at depths of 50 cm in the soil

Control of Warts

largely on the breeding of resistance varieties of potato

Snowdrops

immune from the disease and could be planted on land heavily infected without developing warts

Plasmodiophora division.

Mastigomycota.

Plasmodiophora Subdivision.

Haplomastidomycotina.

Plasmodiophora class

plasmodiophoromycetes

Plasmodiophora order

Plasmodiophorales

Plasmodiophora Family

plasmodiophorceae

Club roots

caused by Plasmodiophora brassicae

club root disease found in

cabbage, cauliflower, turnip, and radish

Plasmodiophora characteristics

obligate endoparasites of aquatic and terrestrial plants, algae and fungi. causes both hypertrophy and / or hyperplasia

Hypertrophy

enlargement of host cells

hyperplasia

abnormal multiplication of cells

A

Posteriorly uniflagellate zoospores. (whiplash flagella)

B

Anteriorly uniflagellate zoospores. (tinsel flagella)

C

Anteriorly biflagellate zoospores. (whiplash and tinsel flagellum)

D

Laterally biflagellate zoospores. ( tinsel upwards and whiplash downwards)

E

Laterally biflagellate zoospores. (both whiplash)

Synchytrium endobioticum causes wart disease of potato

Sexual reproduction

Asexual reproduction

cells undergoing isogamy, plasmogamy, and karyogamy

resting spore in a wart of a potato

zoosporangium

Plasmodiophora brassicae

A

In the root

B

In the soil

C

In the root hair

the life cycle of a Plasmodiophora

Holocarpic

denoting a fungus in which the entire thallus is differentiated into a reproductive sporangium when mature

Eucarpic

denoting a fungus in which the thallus is differentiated into vegetative and reproductive regions