Q. Select a correct statement w.r.t. dikaryotic phase in fungi:
Solution:
Sexual reproduction in fungi:
Except Deuteromycotina (Fungi imperfecti), amphimixis is found altogether groups of fungi. During sexual reproduction, the compatible nuclei show a selected behaviour. This is often liable for the onset of three distinct mycelial phases as follows-
- Plasmogamy: Fusion of two protoplasts.
- Karyogamy: Fusion of two nuclei.
- Meiosis: The educational division.
These three events are liable for the arrival of the subsequent three mycelial phases :
- Haplophase: As a result of meiosis the haploid (n) or haplophase mycelium is made.
- Dikaryotic phase: The plasmogamy leads to the formation of dikaryotic mycelium (n + n). It occurs when karyogamy is delayed.
- Diplophase: As a result of karyogamy the diplophase mycelium (2n) is made.
In some fungi plasmogamy, karyogamy and meiosis do occur during a regular sequence but not at a specified time or points within the life cycle. Such a cycle is described as parasexual cycle and phenomena celled parasexuality recorded by Pontecorvo and Roper.
Except Deuteromycotina (Fungi imperfecti), amphimixis is found altogether groups of fungi. During sexual reproduction, the compatible nuclei show a selected behaviour. This is often liable for the onset of three distinct mycelial phases as follows-
- Plasmogamy: Fusion of two protoplasts.
- Karyogamy: Fusion of two nuclei.
- Meiosis: The educational division.
- Haplophase: As a result of meiosis the haploid (n) or haplophase mycelium is made.
- Dikaryotic phase: The plasmogamy leads to the formation of dikaryotic mycelium (n + n). It occurs when karyogamy is delayed.
- Diplophase: As a result of karyogamy the diplophase mycelium (2n) is made.