Reproduction in Fungi (3 Types of Reproduction) | Mycology

In this article we will discuss about reproduction in fungi :- Vegetative reproduction in fungi, asexual reproduction in fungi and sexual reproduction in fungi

Reproduction in Fungi

• The production of new individuals from parent organisms is called Reproduction.
• Reproduction in fungi takes place by vegetative, asexual and sexual methods.

1. Vegetative Reproduction in Fungi

• A portion of body becomes separated off and gives rise to new individual is called vegetative reproduction
• In vegetative reproduction the union of mature sex cells or sex organs does not involve.
• The common method of vegetative reproduction are: Fragmentations, Fission and Budding

A. Fragmentation

• In this process, the mycelium breaks into two or more similar fragments either accidentally or due to some external force.
• Each fragment grows into a new mycelium.
• E.g., Aspergillus, Alternaria, Mucor and Rhizopus

B. Fission

• The parent cell splits into two equal halves.
• Each of these halves then develops into a new individual
• E.g., Yeast

C. Budding

• The parent cell produces one or more projections called buds.
• The bud detaches and grows into a new individual.
• E.g., Yeast, Ustilago

2. Asexual Reproduction in Fungi

• It is the type of reproduction, a special reproductive structures called spores or propagates are formed.
• About 20% fungi have only asexual reproduction.
• The fungal spores always result from mitosis and hence are described as mitospores.
• The different types of asexual spores in fungi are: Zoospores, Conidiophore, Chlamydospores, Oidia and Aplanospores

A. Zoospores

• They are flagellated, motile spores produced inside structures called zoosporangia.
• These spores do not have a cell wall.
• E.g., Achyla, Pythium, Phytophthora, Albugo

B. Conidiophore or Conidia

• These are non-motile spores produced singly or in chains at the tip of the hypha branches that are called conidiophores.
• E.g., Aspergillus and Penicillium.

C. Chlamydospores

• These are thick walled resting spores which arise directly from hyphal cells.
• They store reserve food.
• E.g., Ustilago

D. Oidia

• These are spore like structures formed by the breaking up of hypha cells.
• They do not store reserve food and hence cannot survive under unfavourable conditions.
• E.g., Collybia, Coprinus

E. Aplanospores

• These are non-motile, thick wall spores produced inside structures called sporangia.
• They are dispersed by wind or water currents.
• E.g., Mucor, Rhizopus and Pilobolus

3. Sexual Reproduction in Fungi

• Sexual reproduction occur in all groups of fungi except Dueteromycetes (Fungi imperfecti).
• Sexual reproduction is carried out by fusion of compatible nuclei of two parent cell.
• The process of sexual reproduction involves three phases:
  • Plasmogamy: fusion of protoplasm of two compatible haploid cells.
  • Karyogamy: fusion of the two haploid nuclei within the dikaryotic cell.
    • In Phycomycetes: Karyogamy just after plasmogamy
    • In Ascomycetes and Basidiomycetes: Karyogamy after some time.
  • Meiosis: The diploid zygote undergoes meiosis, a type of cell division that reduces chromosome number by half. This produces haploid spores, which can germinate to form new fungal hyphae.