Fungal reproduction

Do fungi reproduce in nature most frequently using sexual or asexual reproduction? 

Asexual

Do fungi reproduce in nature most frequently using sexual or asexual reproduction? 

Asexual

What are the general characteristics of sexual reproduction in fungi?

• Diploid stage

• The fusion of (haploid) nuclei from compatible mating types 

• Creates a diploid nuclei, then undergoes meiosis, creating haploid spores

• Involves the production of gametangia (grow towards opposite mating types) in filamentous fungi

What is meant by bipolar compatibility? By tetrapolar compatibility?

Bipolar: 

• 1 mating Locus, 2 alleles (+ and -, so a - and - cannot happen) 

Tetrapolar

• 2 mating locus, 2 or more alleles 

• A, B locus , alleles, A1,A2,...

• Ex A1B1 a partner has to be different at both loci 

Homothallic:

Self fertilization

Heterothallic

 needs partner

Plasmogamy

cytoplasm fuse

Karyogamy

Fusion of nuclei 

Dikaryon

2 nuclei in cytoplasm 

What are the general steps that occur during sexual reproduction in fungi? Be able to describe the major events at each step.

• Secretion and detection of pheromones 

• Production of gametangia (specialized hyphae grows towards) 

• Plasmogamy (degrade cell wall, membranes fuse) 

  • Dikaryon (2 nucleotides)  

• Karyogamy: nuclei fuse for diploid nucleus

• Meiosis (genetic recombination, and reductive division) 

• Formation of sexual spore