General characters of Basidiomycetes

Basidiomycetes

1.The mycelium is branched,septate with simple pore (Uredinales & Ustilaginales ) & dolipore (Agaricales)

2. The mycelia are of 3 types:

Primary: Monokaryotic, ephemeral & formed from basidiospores .

Secondary: Dikaryotic & formed by the dikaryotization of primary mycelium .

Tertiary: Dikaryotic ,formed from the secondary mycelium & termed as basidiocarp (Agaricus , Polyporus,etc.)

3 .There is no specialized sex organs  and sexual reproduction is just the fusion of two nuclei of different strains (+& -).

4. Meiosis takes place immediately after karyogamy in basidium to form 4 haploid nucleus which are lastly converted to exogenous basidiospores.

5.Clamp connection is a common phenomenon.

6. Basidia are of 2 types:

Holobasidium is non-septate having 4 terminal sterigmata bearing a spore at the tip .

Phragmobasidium is septate bearing a lateral sterigmata with a spore .

Difference between Basidiomycetes and Ascomycetes

(1) Septation:

 In Basidiomycetes septal pore is dolipore type .On the other hand in Ascomycetes it is simple type.

(2) Primary mycelium:

Short lived in Basidiomycetes,but long-lived in Ascomycetes.

(3) Dikaryophase:

Long-lived in Basidiomycetes, opposite in Ascomycetes.

(4) Sexual apparatus:

Ill-developed in Basidiomycetes or lacking, degenerating in Ascomycetes.

(5) Basidiomycetes show Clamp connection,whereas Ascomycetes show Crozier formation.

(6)Spore formation:

Exogenous in Basidiomycetes, whereas endogenous in Ascomycetes.

(7) Number of spore :

Usually 4 per basidia & 8 per ascus.

(8)Fruit body:

Basidiocarp is entirely of dikaryotic, whereas ascocarp may be of both of monokaryotic or dikaryotic.