Mycology /studie of fungi

1. MYCOLOGY
Presented by –
Bhoomi Shah

2. CLASSIFICATION OF FUNGI

3.  CLASSIFICATION OF FUNGI BY AINSWORTH G. C. (1966, 71, 73):
Ainsworth G. C. Proposed a more natural system of classification of fungi. This
classification is based on morphology, especially of reproductive structure. He
includes fungi along with slime molds under the kingdom mycota.
Based on the presence or absence of plasmodium and
pseudoplasmodium; the kingdom mycota is further divided into two
divisions:
• Myxomycota i.E., Slime molds and eumycota or true fungi.
• Divisions are subsequently divided into subdivision, class, subclass, order, family
and then to genus.
• According to his classification, division ends in mycota, subdivision in mycotina,
class in mycetes, subclass in mycetidae order in ales and family in aceae.

4. A SCHEMATIC OUTLINE OF AINSWORTH’S
(1973) CLASSIFICATION IS GIVEN:
Kingdom: Mycota
i. Free-living, parasitic or mutualistic symbionts, devoid of chlorophyll.
ii. Cell wall composition is very variable, majority contain chitin and glucan.
iii. Reserve food materials are oil, mannitol and glycogen.
iv. Except some unicellular members, majority are filamentous.
A. Division- Myxomycota
Wall-less organisms possess either a plasmodium (a mass of naked multinucleate protoplasm having amoeboid
movement) or a pseudoplasmodium (an aggregation of separate amoeboid cells). Both are of slimy consistency,
hence slime molds.
1. Class- Acrasiomycetes (cellular slime molds)
2. Class- Hydromyxomycetes (net slime molds)
3. Class-Myxomycetes (true slime molds)
4. Class- Plasmodiophoromycetes (endo- parasitic slime molds).

5. B. Division- eumycota (true fungi, all with walls):
a. Subdivision - mastigomycotina (motile cells – zoospores present, perfect state spore-
oospore).
1. Class- Chitridiomycetes (unicellular, zoospore with single whiplash flagellum).
2. Class- Hyphochytridiomycetes (unicellular, zoospore with single tinsel flagellum).
3. Class- Oomycetes (aseptate mycelium, zoospores with two flagella).
b. Subdivision- zygomycotina (mycelium aseptate, perfect state spore-zygospore).
1. Class- Zygomycetes (mycelium immersed in the host tissue).
2. Class- Trichomycetes (mycelium not immersed in the host tissue).
c. Subdivision- Ascomycotina (yeasts or septate mycelium, perfect state spore- ascospores
formed in ascus, usually within ascocarp).
1. Class- Hemiascomycetes (no ascocarp, asci naked).
2. Class- Loculoascomycetes (fruit body an ascostroma, asci bitunicate i.E., 2-walled).
3. Class- Plectomycetes (fruit body cleistothecium, asci unitunicate i.E., 1-walled).

6. 4. Class- Laboulbeniomycetes (fruit body perithecium, asci unitunicate, exoparasite of arthopods).
5. Class- Pyrenomycetes (fruit body perithecium, asci unitunicate, not parasitic on arthopods).
6. Class- Discomycetes (fruit body apothecium, asci unitunicate).
d. Subdivision- Basidiomycotina (yeast or septate mycelium, perfect state spore – basidiospore formed on a basidium).
1. Class. Teliomycetes
 Basidiocarp lacking, teliospores grouped in sori or scattered within the host tissue, parasitic on vascular plant.
2. Class. Hymenomycetes.
 Basidiocarp present.
 Hymenium is completely or partly exposed at maturity.
 Basidiospore ballistospores.
3. Class. Casteromycetes
 Basidiocarp present.
 Hymenium enclosed in basidiocarp.
 Basidiospore not ballistospores.

7. e. subdivision- Deuteromycotina or fungi imperfecti. Yeast or septate mycelium. Perfect state
unknown.
1. Class. Blastomycetes.
 Budding (yeast or yeast like) cells with or without pseudomycelium.
 True mycelium lacking or not well-developed.
2. Class. Hyphomycetes
 Mycelia sterile or bearing asexual spore directly or on conidiophore, in various aggregation.
3. Class. Coelomycetes
 Mycelial; asexual spore formed in pycnidium or acervulus.

12. NUTRITION IN FUNGI

13. CONTENT
NUTRITIONAL REQUIREMENTS
ESSENTIAL ELEMENTS
SOURCE OF MACROELEMENTS
MODES OF NUTRITION
MECHANISM OF NUTRITION

14. • It is the process of procuring nourishment or nutrient and is the principal
function of the vegetative phase.
• The supply of nutrition is essential for every living organism because the
nutrients serve the structure unit and source for the building up protoplasm
which is the basic of life.
• The fungi are chlorophyl less plants & cannot synthesize their own food
unlike green plants carbon dioxide & water in the presence of sunlight.
NUTRITION IN FUNGI

15. • They are so simple in structure that they cannot obtain inorganic food directly
from the soil, and therefore they are always dependent for their food on some
dead organic materials or living beings.
• The fungi which obtain their food from dead organic materials are called the
saprophytes whereas the fungi obtaining their prepared food from living
plants or animals are called the parasites.

16. NUTRIOTION REQUIREMENTS
• The fungi utilise both organic compounds and inorganic materials as the
source of their nutrition supply. In other words, organic and inorganic
compounds constitute their food.
• No fungi is able to make their food, because of lacking chlorophyll the fungi
are unable to photosynthesize and use carbon dioxide to build up organic food
materials. They are, thus heterotrophic.

17. ESSENTIAL ELEMENTS
• The constituent element of the organic and inorganic substances which fungi
make use of are C, O, H, N, P, K, Mg, Cu, Mn, Mo, Fe, Zn. Calcium is
required by some fungi but not all. These elements which fungi require as food
are termed the essential elements.
• The fungi need in extremely small trance amounts and the others in
comparatively larger amounts. The former are called the trance or micro
elements and the latter macro elements.

18. SOURCES OF MACROELEMENTS.
• The organic substance usually utilized by fungi are very varied in nature.
The carbohydrates are needed for building up the body and also as a source
of energy.
• In typical fungus,50% of the dry weight is carbon next in preference are the
fructose. Less commonly used are the hexose sugars and some pentose.
• Some fungi are able to make good growth on fats as the only sources of
carbon.

19. • Many elements such as hydrogen, oxygen, nitrogen, small amount of
potassium, phoshours & sulphur with the trance of magnesium & iron are
required for the growth and other metabolic activities of the fungi
• Each fungus has its own specific requirements which may be known
experimentally.
• Most fungi are able to synthesize the vitamins they need.

20. MODES OF NUTRITION
• THE FUNGI LACK CHLOROPHYLL. THEY ARE, THEREFORE UNABLE
TO SYNTHESIZE CARBOHYDRATE FOOD FROM INORGANIC
MATERIALS AND GET IT READYMADE FROM SOURCE EXTERNAL TO
THEMSELVES.
• THESE HETERONOMOUS ACCORDING THEIR METHOD OF
OBTAINING FOOD ARE DIVIDED INTO TWO CATEGORIES, NAMELY,
THE SAPROPHYTIC OR SAPROBES AND PARASITES. THE
SAPROPHYTES CANNOT INGEST SOLID FOOD.
• THE PARASITE LIVES IN OR ON THE LIVING BODY OF A PLANT OR
PLANT OR ANIMAL AND ABSORBS ORGANIC MOLECULES AS

21. MECHANISM OF NUTRITION
• THE WHOLE MYCELIUM MAY HAVE THE POWER TO
ABSORB THESE NUTRIENTS OR THIS TASK MAY BE
ASSIGNED TO SPECIAL PORTIONS OF THE MYCELIUM.
• IN SAPROPHYTIC FUNGI, THE HYPHAE OR RHIZOIDAL
HYPHAE COME IN INTIMATE CONTACT WITH THE
NUTRIENT IN THE SUBSTRUM AND ABSORB SOLUBLE
SMALLER MOLECULES SUCH AS SUGAR AND AMINO ACID.
• THE FUNGAL HYPHAE SECRET ENZYMES WHICH CONVERT
INSOLUBLE FOOD MATERIALS IN THE SUBSTRATUM TO
SOLUBLE ONCE.

22. • THE MYCELIUM OF THE PARASITES IS RARELY ECTOPHYTIC BUT
FREQUENTLY IT GROWS INSIDE THE HOST. THE HYPHAE EITHER
RAMIFY IN THE INTERCELLULAR SPACE BETWEEN THE HOST CELLS
OR PENETRATE INTO THE HOST CELLS.
• THE INTERCELLULAR HYPHAE OBTAIN NUTRITION THROUGH THE
CELL WALLS OR MEMBRANE OF THE HOST CELLS.
• THE FORMER ARE CALLED INTERCELLULAR AND THE LATTER
INTERCELLULAR HYPHAE. THE INTERCELLULAR HYPHAE OBTAIN
NUTRITION THROUGH THE CELL WALL OR MEMBRANE OF THE HOST
CELL.

23. • IT MAKES THE MEMBRANE MORE PERMEABLE TO ON THE
CONTAINED SOLUTES.
• THE INTERCELLULAR HYPHAE OF SOME HIGHLY SPECIALIZED PLANT
PARASITES GIVE OUT SLENDER, LATERAL OUTGROWTHS.
• THE HYPHAL OUTGROWTH PUNCTURES THE HOST CELL WALL
MAKING A MINUTE PORE THROUGH WHICH IT ENTERS THE HOST
CELL.

24. MECHANISM OF
NUTRITION

25. •The intercellular hyphae of
some highly specialized plant
parasites give out slender,
lateral outgrowths. It punctures
the host cell wall making a
minute pore through which
enters the hostcell.
•This type of feeding organ of
the parasitic fungi is called a
haustorium.
•The haustorium is intracellular
and thus robs the host of its
food without killing it.
Haustorium are characteristic of
obligate parasites.

26. • THE FUNGI AS MENTIONED ABOVE ARE UNABLE TO SYNTHESIZE SUGARS FROM CARBON DIOXIDE
AND WATER.
• MANY FUNGI OBTAIN NUTRITION BY LIVING IN MUTUALLY BENEFICIAL ASSOCIATIONS WITH OTHER
PLANTS.
• THE ASSOCIATION IS NOT CAUSAL BUT PERMANENT AND IS ESTABLISHED DURING LONG PROCESS
OF EVOLUTION
• THE TWO BEST KNOWN EXAMPLES OF MUTUALIST ASSOCIATIONS OF FUNGI WITH OTHER PLANS ARE
SYMBIOSIS AND MYCORRHIZA.

27. • The common example of Symbiosis is
an association of a fungus and an
Algae in a lichen thallus.
• The duty of alga in this partnership is
to synthesize food with the help of
green chloroplast and share it with
its fungal partner.
• The fungal absorbs minerals in
solution and water from the
substratum and passes them on to
alga.
a. Symbiosis

28. B. MYCORRHIZA
• IT IS DEFINED AS THE SYMBIOTIC ASSOCIATIONS BETWEEN THE HYPHAE OF
CERTAIN FUNGI AND ROOTS OF PLANTS. IT IS OF THREE TYPES:
1. ECTOMYCORRHIZA
2. ENDOMYCORRHIZA
3. ECTOENDOMYCORRHIZA

29. 1.ECTOMYCORRHIZA
• The fungal hyphae in this case form a
complete envelope around the root tip and
also penetrate and extend into the first few
cortical layers to form an intercellular
network of hyphae known as the Hartignet.
• The presence of the fungus thus increases
root absorption. In return fungus receive
food.

30. 2. ENDOMYCORRHIZA
• The fungal hyphae in this case penetrate root
hairs.
• Epidermis and reach the cortex where they
grow intracellular forming fungal knots in the
cortical cells.
• A portion of the mycelium lives in the soil but it
forms no dense hyphal growth.

31. 3. ECTOENDOMYCORRHIZA
• It is a combination of the first two.
• The fungal hyphae form a sheath at the
surface of the root.
• Within the root they grow intercellular
and intracellular.

32. SAPROPHYTES
• SAPROPHYTES FUNGI LIVE ON DEAD ORGANIC
MATERIALS PRODUCED BY THE DECAY OF ANIMALS
& PLANTS TISSUES.
• THEY GROW UPON DEAD ORGANIC MATTERS SUCH
AS ROTTEN FRUITS, ROTTEN VEGETABLES, MOIST
WOOD, MOIST LEATHER. JAMS, PICKLES, CHEESE,
MOIST BREAD, &MANY OTHER POSSIBLE DEAD
ORGANIC MATERIALS.

33. PARASITE
•The parasitic fungi absorb their food material from the
living tissues of the hosts on which they parasitize.
•Such parasitic fungi are quite harmful totheur hosts and
cause many serious diseases.
•These fungi cause the great losses to the human beings
or indirectly.
•Many diseases of the important crops are caused by
parasitic fungi.

34. 34

35. CONTENT
 INTRODUCTION
 DEFINITION & TYPES OF REPRODUCTION.
VEGETATIVE REPRODUCTION
¤ FRAGMENTATION, FISSION, BUDDING, SCLEROTIA, RHIZOMORPH.
ASEXUAL REPRODUCTION
¤ ENDOGENOUS SPORES
¤ EXOGENOUS SPORES
SEXUAL REPRODUCTION
¤ PLASMOGAMY
¤ KARYOGAMY
¤ MEIOSIS
¤ METHODS OF SEXUAL REPRODUCTION
35

36.  DEFINITION :
 FUNGI ARE REPRODUCE WITH ALL THE CHARACTERISTICS
TYPICAL OF THE SPECIES AND THE FORMATION OF NEW
INDIVIDUALS.
SOME OF THE IMPORTANT METHODS OF REPRODUCTION IN FUNGI
ARE AS FOLLOWED :
1. VEGETATIVE REPRODUCTION
2. ASEXUAL REPRODUCTION
3. SEXUAL REPRODUCTION.
36

37. 1.VEGETATIVE
REPRODUCTION
 VEGETATIVE REPRODUCTION DOES NOT INVOLVE THE UNION OF NUCLEI, SEX CELLS
(GAMETES) OR SEX ORGANS (GAMATANGIA).
 VEGETATIVE REPRODUCTION HELPS TO INCREASE THE NUMBER OF INDIVIDUALS IN
THE POPULATIONS.
 VEGETATIVE REPRODUCTION IN FUNGI OCCURS BY :
 FRAGMENTATION
FISSION
BUDDING
SCLEROTIA
RHIZOMORPHS
37

38.  FRAGMENTATION :
 THE MYCELIUM BREAK UP INTO SMALL FRAGMENTS OR PIECES AND EACH OF WHICH IS ABLE TO
DEVELOP INTO NEW INDIVIDUALS.
 THIS IS OF TWO TYPES:(A)ACCIDENTAL:(LIKE A FAST FLOWING WATER)
(B) PURPOSIVE :(LIKE VEGETATIVE REP.)
 COMMON IN FILAMENTOUS FUNGI. ( RHIZOPUS,ASPERGILLUS) (CLASS- ASCOMYCOTA,
BASIDIOMYCOTA)
FISSION :
 MATURE CELLS ARE MITOTICALLY DIVIDED INTO TWO DAUGHTER CELLS AND RISE TO NEW
INDIVIDUALS.
 OCCURS IN UNICELLULAR FUNGI. ( YEAST)
38

39.  BUDDING :
 THE PRODUCTION OF A SMALL NEW CELL FROM THE OUTGROWTH (BUD) OF A
CELL IT’S CALLED BUDDING.
 PSEUDO MYCELIUM : CHAINS OF BUDS , IS IT.
 OCCURS IN UNICELLULAR FORMS SUCH AS YEAST. (CLASS – SACCHAROMYCES
).
39

40.  SCLEROTIA :
 SCLEROTIA ARE PSEUDO PARENCHYMATOUS MYCELIUM
AGGREGATIONS.
 THE SCLEROTIA ARE RESISTANT AND PARENNATING BODIES SO THEY
SURVIVE FOR MANY YEARS.
 EACH SCLEROTIUM IS CUSHION-LIKE STRUCTURE OF COMPACT
MYCELIUM.
 THE COMPACT MYCELIUM GIVE A RISE TO NEW MYCELIA ON THE
APPROACH OF FAVOURABLE CONDITIONS.
 E.G. CLAVICEPS PURPUREA , RHIZOCTONIA SOLANI.
 RHIZOMORPH :
 MODIFIED MYCELIUM, THE ROPE LIKE RHIZOMORPHS ARE ALSO
RESISTANT TO UNFAVOURABLE CONDITIONS, AFTER SEVERAL YEARS ON
THE APPROACH OF FAVOURABLE CONDITIONS THEY GIVE RISE TO NEW
40

41. 2. ASEXUAL REPRODUCTION
 THE ASEXUAL REPRODUCTION TAKES PLACE BY MEANS OF SPORES , ANY SPORES FORMED ARE THUS
MITOSPORES, AND NOT THE ZYGOTES OR MEIOSPORES. EACH SPORE MAY DEVELOP INTO A NEW
INDIVIDUAL.
 SPOROPHORES : THE SPORES ARE OF DIVERSE TYPE AND BORNE UPON SPECIAL STRUCTURES, IT
IS ..
 PLEOMORPHIC / POLYMORPHIC : WHEN THE FUNGUS PRODUCING MORE THAN ONE TYPES OF THE
SPORES IT’S CALLED IT IS.
 FOLLOWING THE SPORE’S PLACE ON THE SPORANGIA , THERE ARE TWO TYPES SPORE IN THE ASEXUAL
SPORES.
(A) ENDOGENOUS SPORES
(B) EXOGENOUS SPORES
ZOOSPIRANGIUM & ZOOSPORE OF
PHYTOPHTHORA CONIDIOPHORES & CONIDIA
OF PENICILIUM
41

42. (A) ENDOGENOUS SPORES :
 THE SPORES PRODUSED INSIDE THE SPORANGIA ARE TERMED THE ENDOGENOUS SPORES.
 SPORANGIUM: THE ENDOGENOUS SPORES ARE PRODUCED WITHIN THE SPECIAL SPORE PRODUCING
CELL IT’S CALLED IT.
 SPORANGIOPHORES: THE SPOROPHORES WHICH BEAR THE SPORANGIA ON THEIR APICES ARE
CALLED THE SPORANGIOPHORES.
 ENDOGENOUS SPORES ARE TWO TYPES :
(A) APLANOSPORES
(B) ZOOSPORES
42

43. (A) APLANOSPORES :
 THE APLANOSPORES ARE NON-MOTILE, WITHOUT FLAGELLA AND THEY MAY
BE UNI / MULTINUCLEATE.
 THEY LACK VACUOLES.
 THEY POSSESS TWO LAYERED CELL WALLS.
• EPISPORE / EXOSPORE: THE OUTER THICK LAYER.
• ENDOSPORE : THE INNER THICK LAYER.
 E.G. MUCOR,RHIZOPUS APLANOSPORE OF
MUCOR RHIZOPUS
APLANOSPORE & CLEISTOTHESIUM OF ERYSIPHE
43

44. (B) ZOOSPORES :
 ZOOSPORES ARE MOTILE AND THEY HAVE UNI/BIFLAGELLATE , WITHOUT ANY
CELL WALL , UNINUCLEATE , VACUOLATE.
 USUALLY KIDNEY SHAPED OR RENIFORM.
 THE FLAGELLA ARE INSERTED POSTERIORLY OR LATERALLY ON THEM.
E.G. ALBUGO, PYTHIUM, PHYTOPHTHORA AND MANY OTHER LOWER FUNGI.
ALBUGO SPORANGIUM & ZOOSPORES OF
PHYTOPHTHORA 44

45. (B) EXOGENOUS SPORES :
 THE SPORES PRODUSING EXTERNALLY OR EXOGENOUSLY ON THE TERMINAL ENDS OF
SPOROPHORES ARE CALLED THE EXOGENOUS SPORES OR CONIDIA.
• CONIDIOPHORES : WHICH PART IS PRODUCED CONIDIA EXTERNALLY ON THE BRANCHED OR
UNBRANCHED IT’S CALLED IT.
 THE CONIDIA ARE DIVERSE IN THEIR SHAPE AND SIZE & ALSO IN COLOUR, UNI/MULTI CELLULAR
AND UNI/MULTI NUCLEATE.
 THE BLUE-GREEN MOLDS : THE CONIDIA OF ASPERGILLUS & PENICILLIUM ARE SMOKY GREEN
COLOURED SO THE FUNGI ARE CALLED IT.
 IN OTHER TYPE OF EXOSPORES, THE SPOROPHORES DEVELOP IN GROUPS AND FORM THE
SPECIALIZED STRUCTURE CALLED THE PUSTULES, PYCNIDIA, AECIDIA, AND SPORODOCHIA.
45

46.  OTHER TYPES OF EXOSPORES :
CONIDIA OF ASPERGILLUS CONIDIA OF CERCOSPORA
CONIDIA OF COLLETOTRICHUM CONIDIA OF FUSARIUM CONIDIOPHORE & CONIDIA OF
PENICILLIUM
46

47. 47

48. 3. SEXUAL REPRODUCTION
 UNION OF TWO NUCLEI OR GAMETES OF OPPOSITE SEX , A
GAMETE IS UNISEXUAL (HAPLOID) IT’S CALLED THE SEXUAL
REPRODUCTION.
 DEUTEROMYCETES LACK SEXUAL REPRODUCTION.
THERE ARE TWO DISTINCT PHASES IN THE LIFE CYCLE :
(1) HAPLOID PHASE : (X) NUMBER OF CHROMOSOMES IN THE
NUCLEUS.
(2) DIPLOID PHASES : (2X) NUMBERS OF CHROMOSOMES IN
(A) ENDS WITH FERTILIZATION,
(B) WITH MEIOSIS.
48

49. MONOECIOUS / HOMOTHALLIC:
 WHEN BOTH THE SEX ORGANS OR STRAINS OCCUR ON THE SAME MYCELIUM,
THIS FUNGUS IS SAID TO BE MONOECIOUS / HOMOTHALLIC.
DIOECIOUS / HETEROTHALLIC:
 WHEN THE MALE AND FEMALE SEX ORGANS OR PLUS OR MINUS STRAINS
OCCUR SEPARATELY ON DIFFERENT MYCELIA, THIS FUNGUS IS SAID TO BE
DIOECIOUS / HETEROTHALLIC.
ISOGAMY :
 THE MORPHOLOGICALLY SIMILAR IDENTICAL MALE AND FEMALE GAMETES
ARE CALLED THE ISOGAMETES AND WHEN FUSION TO EACH OTHER THAN IT’S
CALLED ISOGAMY.
49

50.  ANISOGAMY :
 THE MORPHOLOGICALLY DISSIMILAR MALE AND FEMALE GAMETE
ARE CALLED THE HETEROGAMETES, WHEN THEY FUSION TO EACH
OTHER THAN IT’S CALLED ANISOGAMY.
50

51. PLASMOGAMY :
THE FUSION OF THE PLASMA OF THE GAMETES
KARYOGAMY :
 THE FUSION OF THE NUCLEAR OF THE GAMETES
 KARYOGAMY IN LOWER FUNGI: THERE IS COMPLETE FUSION OF THE NUCLEI OF
THE TWO DIFFERENT STRAINED GAMETES IN THE SEXUAL UNION.
 DICARYONS IN HIGHER FUNGI: THE FUSION OF THE TWO NUCLEI OF DIFFERENT
STRAINS IS DELAYED AND THE PAIRS OF THE NUCLEI, IT’S CALLED THE
DICARYONS.
51

52.  DICARYOTIC MYCELIUM : THE MYCELIUM HAVING SUCH PAIRS OF NUCLEI IS CALLED THE
DICARYOTIC MYCELIUM.
 MONOCARYOTIC MYCELIUM : WHERE THE MYCELIUM POSSESSES SINGLE HAPLOID NUCLEUS
OF EITHER STRAIN IN EACH CELL IS CALLED THE MONOCARYOTIC MYCELIUM.
 MEIOSIS :
ZYGOTE IMMEDIATELY UNDERGO MEIOSIS TO PRODUCE MEIOSPORES.
AFTER KARYOGAMY REDUCTION DIVISION TAKES PLACES IN THE DIPLOID NUCLEUS AND THUS
HAPLOID STAGE IS ESTABLISHED.
52

53. METHODS OF SEXUAL
REPRODUCTION
 THE MOST COMMAN METHODS OF SEXUAL REPRODUCTION ARE
AS FOLLOWS :
1) PLANOGAMETIC COPULATION
2) GAMETANGIAL CONTACT
3) GAMETANGIAL COPULATION
4) SPERMATIZATION
5) SOMATOGAMY 53

54. 1)PLANOGAMETIC COPULATION :
 INVOLVE THE FUSION OF TWO NAKED GAMETES .
 ONE OR BOTH GAMETES ARE MOTILE, MOTILE GAMETES ARE KNOWN AS
PLANOGAMETES.
 ISOGAMOUS PLANOGAMETES : SYNCHYTRIUM , PLASMODIOPHORA….
 ANISOGAMOUS PLANOGAMETES : ALLOMYCES
 OOGAMOUS :MONOBLEPHARIS
54

55. 2) GAMETANGIAL CONTACT :
FOUND IN MANY LOWER FUNGI. ( CLASS- PHYCOMYCETES).
 IN THIS METHOD TWO GAMETANGIA OF OPPOSITE SEX (OOGONIUM AND
ANTHERIDIUM ) COME IN CONTACT AND ONE OR MORE GAMETE NUCLEI
MIGRATE FROM THE MALE GAMETANGIUM (ANTHERIDIUM) TO THE FEMALE
GAMETANGIUM (OOGONIUM).
MALE NUCLEI MIGRATE TO FEMALE GAMETANGIUM BY DISSOLUTION OF WALL.
E.G., ASPERGILLUS, PENICILLIUM ETC.
55

56. IN OTHER SPECIES THE MALE NUCLEI MIGRATE THROUGH A FERTILIZATION TUBE.
E.G., PYTHIUM , ALBUGO , PERONOSPORA ETC.
56

57. 3) GAMETANGIAL COPULATION :
 THE FUSION OF THE ENTIRE CONTENTS OF TWO CONTACTING COMPATIBLE
GAMETANGIA TAKES PLACE ( BY PORE )
E.G., MUCOR , RHIZOPUS , ENTOMOPHTHORA ETC.
57

58. 4) SPERMATIZATION :
IN SOME ADVANCED FUNGI SEX ORGANS ARE COMPLETELY ABSENT.
HERE SEXUAL PROCESS IS ACCOMPLISHED BY MINUTE SPORE LIKE SPERMATIA
AND SPECIALIZED HYPHAE ACTING AS MALE AND FEMALE STRUCTURE.
SPERMATIA IS CARRIED BY AIR, WATER OR INSECT TO THE RECEPTIVE
HYPHAE.
SPERMATIA ATTACHED TO THE TRICHOGYNE OF RECEPTIVE HYPHAE AND
MIGRATE INTO THE CYTOPLASM.
58

59. 5) SOMATOGAMY :
 SEX ORGANS ARE NOT PRODUSED.
TWO SOMATIC CELLS TAKE PART IN SEXUAL FUNCTION AND FUSE TOGETHER.
E.G., MORCHELLA, PEZIZA, AGARICUS & MANY HIGHER FUNGI.
59

61. CONTENT
INTRODUCTION
MORPHOLOGICAL HETEROTHALLISM
PHYSIOLOGICAL HETEROTHALLISM
(1) TWO ALLELOMORPHS
(2) MULTIPLE ALLELOMORPH
¤ BIPOLAR MULTIPLE-ALLELE
HETEROTHALLISM.
¤ TETRAPOLAR MULTIPLE-ALLELE
HETEROTHALLISM.

62. INTRODUCTION
 While studying sexual process in mucorales, A.F. Blakeslee (1904) observed
that some species develop zygospores independently.
 Where as other form zygospore only when two mycelia of different strains
come in contact with each other.
 On this basis, he divided the species of mucorales into two
groups, viz., Homothallic and Heterothallic.

63. WHAT IS
HETEROTHALLISM ?
 Heterothallic species have sexes that reside in different individuals. The
term is applied particularly to distinguish heterothallic fungi, which require
two compatible partners to produce sexual spores, from homothallic ones,
which are capable of sexual reproduction from a single organism.
Blakeslee experiment :
Blakeslee proved the phenomenon of heterothallism on the basis of the
experiments he conducted using several species of mucorales.

64.  He inoculated spores of two different strains of mucor hiemalis on the a
petridish containing synthetic agar medium.
 After a few days it was observed that the zygospores were formed along the
zone of contact of two mycelia.
 In another experiment he inoculated spores of only one strain on a petridish
containing synthetic agar medium.
 After sometime observed absolutely no zygospores were prodused in this
experiment.

65. From these experiments
 He conducted that zygospores could be formed
only when mycelia of two different strains
were allowed to come in contact.
 Blakeslee and his co – workers (1928)
examined different genera of mucorales to test
whether these were homothallic or
heterothallic.

66. Since the discovery of heterothallism in mucorales by blakeslee,
the phenomenon has been reported in several groups of fungi.
While in dictyuchus monosporous it is dioecism in ascobolus
magnificus, it is expressed self-sterility.
Both the fungi resemble the heterothallic mucorales in that sex
organs are formed only when opposite strains come in contact.
 In dictyuchus monosporous in
two sex organs they are different
strains.
 In ascobolus magnificus in
each strain are produces sex organs self – sterile.

67. HETEROTHALLISM
MORPHOLOGICAL PHYSIOLOGICAL
HETEROTHALLISM HETEROTHALLISUM
TWO ALLELOMORPHS MULTIPLE ALLELOMORPH
BI-POLAR TETRA-POLAR
MULTIPLE-ALLELE MULTIPLE ALLELE

68. MORPHOLOGICAL
HETEROTHALLISM
When morphologically different male and female sex organs are
present in two closely associated mycelia, it is known as
morphological heterothallism.
The two sex organs are so morphologically different.
This type of heterothallism is found in lower fungi.
Such as achlya ambisexualis, a.Bisexualis, blastocladiella variabilis,
dictyuchus monosporus, phytophthora palmivora and

69. WHITEHOUSE (1949) ALSO USED THE HAPLODIOECIUS
FOR MORPHOLOGICALY HETEROTHALLIC SPECIES OF FUNGI

70. PHYSIOLOGICAL HETEROTHALLISM
In physiological heterothallism, sexual reproduction takes place by two
morphologically similar but physiologically different hyphae.
 The mating hyphae are different in compatibility factors.
Also known as haploid incompatibility.
 It is of the following two types :
(1) two allelomorphs or two-allele heterothallism
 When nuclei of both the mating types are different in genetic characters,this
type known as two-allele heterothallism.

71.  AT THE TIME OF MEIOSIS, SEPARATION OF THE CHROMATIDS TAKE
PLACE.
HALF OF THE HAPLOID SPORES THUS HAVE (+) AND THE OTHER HALF (-)
ALLELE.
THE SPORES BEARING (+) ALLELE WILL PRODUCE (+) MYCELIA AND (-)
ALLELE WILL GIVE RISE TO (-) MYCELIA.
THE MYCELIA OF (+) AND (+) , (-) AND (-) ARE SELF STERILE.
THUS, TWO COMPLIMENTARY MATING TYPES (+) AND (-) ARE ESSENTIAL

72.  IN THESE TYPES COMPATIBILITY IS GOVERND BY A PAIR OF ALLELES
REPRESENTED BY A AND A LOCATED AT SINGLE SAME LOCUS OF
THE CHROMOSOME.
DUE TO THE DOMINAUCE OF A OVEER A, A IS REPRESENTED BY (+)
AND A IS (-).

73. (2) MULTIPLE ALLELOMORPH
 IN THIS TYPE OF HETEROTHALLISM, SEXUAL COMPATIBILITY IS
DETERMINED BY MORE THAN TWO ALLELES.
ONE OR TWO LOCI. BECAUSE OF THE LARGER NUMBER OF ALLELES
INVOLVED IN THIS TYPE , CHANCES OF MATING OF COMPATIBLE
STRAINS INCREASE .
THE MULTIPLE ALLELE HETEROTHALLISM MAY BE OF TWO TYPES :
(A)BIPOLAR MULTIPLE – ALLELE HETEROTHALLISM
(B)TETRAPOLAR MULTIPLE – ALLELE HETEROTHALLISM

74. (A) BIPOLAR MULTIPLE ALEELE
 THIS TYPE OF HETEROTHALLISM IS CONTROLLED BY MULTIPLE
ALLELES AT A SINGLE LOCUS, INSTEAD OF A PAIR OF ALLELES.
 IF THE LOCUS IS NAMED AS L, THE MULTIPLES ALLELES WILL BE
DESIGNATED AS L1,L2,L3,L4-LN AND THESE ARE PRESENT ON THE
SINGLE LOCAL L.
 BIPOLAR MULTIPLE ALLELE
HETEROTHALLISM IS CHARACTE-
RISTIC OF BASIDIOMYCETES
EXPECT RUSTS AND SMUTS.

75. (B) TETRAPOLAR MULTIPLE-ALLELE
HETEROTHALLISM
 THIS TYPE VERY SIMILAR TO BIPOLAR MULTIPLE-ALLELE
HETEROTHALLISM. BUT HERE THE COMPATIBILITY IS DETERMINED
BY TWO LOCI.
 THE COMPATIBILITY FACTOR , I.E., MULTIPLE ALLELE IS PRESENT
ON TWO LOCI ARE SEPARATED WITH THE CHROMATIDS.
 AT THE TIME OF MEIOTIC DIVISION, BOTH THE LOCI ARE
SEPARATED WITH THE CHROMATIDS.

76.  IN SCHIZOPHYLLUM COMMUNE, 122 , ALLELES OF FACTOR A AND
61 OF B HAVE BEEN IDENTIFIED IN THE LABORATORY.
 ACCORDING TO ROUGH ESTIMATES, ABOUT 350-450 OF L1, AND
65 OF L2.

77.  THIS TYPE OF HETEROTHALLISM ENCOURAGES OUT-BREEDING.
WHEREAS BIPOLAR MULTIPLE ALLELE HETEROTHALLISM, THE OUT-
BREEDING IS 25%, IN TETRAPOLAR, IT IS 100%. THIS MAY BE DUE
TO ENORMOUS INCREASE IN THE NUMBER OF POSSIBLE MATING
TYPES OF THALLI.
 ACCORDING TO GARRETT (1963), HETEROTHALLISM PROMOTES
THE OUT-BREEDING AND THEREFORE SUBSERVES THE SAME AND
AS THE SEXUAL PROCESS , WHICH IT RENDERS MOST EFFICIENT.
HETEROTHSAASLLISM IS NOT THE SAME AS SEX, IT IS REFINEMENT
SUPER IMPOSED UPON IT.

78. ECONOMIC IMPORTANCE
OF FUNGI

79. CONTENTS
• INTRODUCTION
• FUNGI AS FOOD AND AS FOODER
• AS A MEDICINE
• INDUSTRIAL USES

80. Introduction
• Fungi include hundreds of fungi species which are of tremendous
economic importance to man.
• In fact our lives are intimately linked with those of fungi.
• Hardly a day passes when we are not benefited or harmed
directly or indirectly by these organisms.

81. • They play an important role in medicine yielding antibiotics in agriculture, by maintaining
the fertility of the soil and causing crop and fruit diseases, forming basis of many industries
and as important means of food.
• Some of the fungi are important research tools in the study of fundamental biological
processes.
• Fungi are important to us as they affect our daily life directly or indirectly. Some of them are
gracious and provide us food, medicine and other items, while others cause diseases in man
and plants and spoil food and other articles.
• Fungi provide us food rich in proteins and carbohydrates, low fats, rich in vitamins and
minerals.

82. Role of fungi as food and as fooder
• Many species of fungi are edible about 2000 species of
them have been reported from all over the world.
• Of these about 200 are said to occur in the western
himalayas.
• Many edible fungi are of great economic values as
food.

84. • Agarics and Marchella, are eaten a food and
cultivated on a commercial basis.
• They are rich source proteins.

85. • The honey coloured mushrooms, the fairy ring mushrooms, the puff balls (lycoperdon,
and clavatia ), morels (morchella, guchhi),and truffles are edible.
• The content of available food in them is not high but they supply vitamins and are
valuble as appetisers.
• Yeasts and some filamentous fungi are valuable sources of vitamins of the b - complex.

86. YEAST CAKES:
The large scale production
of yeast cake is called
microbial farming .These
are prepared by mixing a
large number of yeast cells
with some inert
substances such as ,
starch and then
compressed to form cakes

87. ROLE OF FUNGI IN MEDICINE
• Some fungi produce substances which help to cure diseases caused by
the pathogenic microorganisms. These substance are called the
antibiotics.
• The most important antibiotics are produced by the moulds,
actinomycetes or bacterial.
• The use of antibiotics is not limited to disease treatment. They
discovery of antibiotic agents as drugs is comparatively a recent history.

88. USE IN MEDICINE:
• SOME METABOLIC PRODUCTS
OF FUNGI USED IN MEDICINE
ARE :
• 1. ERGOT
• 2.ANTIBIOTICS
• 3. VITAMINS

89. 1. ERGOT:
• IT IS A MOST USEFUL DRUG
OBTAINED FROM
SCLEROTIA OF CLAVICEPS
PURPUREA . THE FUNGUS IS
PARASITIC ON GRASSES ,
ESPECIALLY RYE .THE
DISEASE IS CALLED
`ERGOT OF RYE`. IT IS
ALSO USED TO INCREASE

90. 2.ANTIBIOTICS:
• AN ORGANIC SUBSTANCE ,
PRODUCED BY
MICROORGANISM , WHICH
INHABIT OR REDUCE THE
GROWTH OF CERTAIN
MICROORGANISM ,IS CALLED
ANTIBIOTIC . SOME OF THE
ANTIBIOTICS OBTAINED FROM
FUNGI IS PENICILLIN ,

91. • The role of fungi in producting antibiotic substance was first established by sir
ALEXANDER FLEMING in 1929.
• He extracted the great antibiotic drug penicillin from penicillium notatum. It was the first
antibiotic to be widely used.
• Penicillin is an organic substance lethal to microbes. It is for more effective than
ordinary drugs and germicides.
• It has no adverse effect on human protoplasm but kills bacteria especially gram- positive
type.

92. 3. VITAMINS:
• Fungi are rich source of many
vitamins. Vitamin B complex is
obtained from yeasts .Other
vitamins obtained from yeasts
and moulds are – vitamin D ,
riboflavin, ergosterol etc.

93. ROLE OF FUNGI IN INDUSTRY
• Fungi are used in industries for manufacturing large varieties of used materials for
mankind such as metabolites, enzymes and food.
• The filamentous fungi are used in many different process in food industry for
manufacture of different metabolites and variety of other processes.

94. INDUSTRIAL USES:
• Fungi are used in many important industries in the production of
varied products .
• 1: alcoholic fermentation
• 2: industrial products
• 3: enzymes
• 4: gibberellic acid

95. ALCOHOLIC FERMETION

96. The common alcoholic beverages-wine and beer are fermentation
products produced by the activity of different species of
saccharomyces. Some of fermentation products are:
1:wine:
wine is made from juice of graps or other fruits by allowing yeast to
induce alcoholic fermentation. It contain about 10 to 12% alcohol.
2:beer:
beer is chiefly made from barley grains.It contain 3 to 8% alcohole .

97. ENZYMES:

98. GIBBERELLINS
• These are plant hormones produced by the fungus gibberella fujikuroi which causes a
disease of rice accompanied by abnormal elongation.
• Gibberellin is a growth promoting hormone obtained from Gibberella. It also accelerates
flowering and breaks dormancy of certain resting bodies such as potato tubers.
• Gibberellin is used to accelerate growth of several horticultural crops.
• The phytohormone gibberellic acid is obtained from the culture of gibberella fujukuroi
and fusariun moniliforme. It is used to induce growth and flowering in plants.

99. GIBBERELLIC ACID:
• The phytohormone gibberellic acid is
obtained from the culture of gibberella
fujukuroi and fusariun moniliforme.It is
used to induce growth and flowering in
plants.

100. REFERENCE
1. A text book of botany fungi: b. P. Pandey
2. fungi and allied organisms: p. D. Sharma
3. A TEXT BOOK OF BOTANY ( volume 1 ): edition: first edition (2008): N.C.
Kumar
4. Botany for degree students fungi by : B.R.Vashishta & A.K. Sinha
5. A text book of botany : P.C pande, D.K. Jain, singh V.
6. An introduction to fungi: Third edition: H.C.Dube
7. Www.Slideshare.Net
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