CLASSIFICATION OF PENICILLIUM (BLUE MOLD)
Kingdom :- Mycota
Division :- Eumycota
Sub-division :- Ascomycotina
Class :- Plectomycetes
Order :- Eurotiales
Family :- Eurotiaceae
Genus :- Penicillium
The Penicillium fungus can easily be found or grown on citrus and other fruits and on foodstuff. It generally grows in association with Aspergillus, but since it is a weak saprophyte it is dominated by Aspergillus.
STUDY OF VEGETATIVE STRUCTURE
- The fungus is a saprophyte and is commonly found on citrus and other fruits, jellies and other foodstuffs.
- The mycelium is freely branched, septate and each cell is uni- or multinucleate.
- The mycelium may grow superficially on the surface of substratum or may penetrate deeply.
- The hyphae are generally coloured due to pigments on the surface of hyphal walls.
STUDY OF CONIDIA
- The conidia are the asexual spores borne on long, erect and branched conidiophores.
- The branched conidiophore, with its conidia looks like a small ‘Penicillus’ (a brush in Latin).Each conidiophore grows vertically from the mycelium and branches at its upper end. The ultimate branches are known as metulae.
- Each branch of conidiophore ends in bottleshaped sterigmata bearing a group of conidia arranged basipetally.
- The conidia are generally blue, sometimes green or -yellow and give characteristic colour to the colony.
- The conidia are globose to ovoid in shape and appear as glass beads under the microscope.
ASCOCARP, ASCI AND ASCOSPORES
- The fruiting body or ascocarp is called cleistothecium. It has a wall-peridium made of sterile hyphae which encloses many asci and paraphyses.
- The globose or pear-shaped asci lie scattered inside the cleistothecium.
- Each ascus has eight uninucleate and wheelshaped ascospores.
- The ascospores are ultimately released by the rupture of cleistothecium and after falling on a suitable medium germinate into new mycelia.
- The perfect stage i.e. cleistothecium is known as Eupenicillium, Teleromyces, Carpenteles.
- Kingdom – Mycota
- Chlorophyll absent
- Reserve food glycogen
- Cell wall of fungal cellulose.
- Division – Eumycota
- A definite cell wall present.
- Sub-division:- Ascomycotina
- Mycelium septate.
- Spores borne endogenously in the ascus.
- Spores in definite numbers, in multiples of two, usually eight.
- Class:- Plectomycetes
- Ascocarp, a cleistothecium.
- Order– Eurotiales
- Cleistothecia sessile
- Family – Eurotiaceae
- Asci lie scattered, hymenium not formed.
- Peridium made of closely interwoven hyphae.
- Genus – Penicillium
- Branched, brush-like conidiophore.