Rhizopus stolonifer

Rhizopus diagram 

General characteristics

1. R. stolonifer (Syn = R. nigricans) is commonly known as "Bread mold".
2. Hyphae are aseptate and multinucleate.
3. Hyphae grow horizontally to the substratum called "stolon".
4. Branched rhizoids are produced at the point where stolon touches the substratum.
5. Opposite to the rhizoids, aerial "sporangiophores" are born.
6. Sporangiophores are long, unbranched and produced in umbell fashion.
7. At the tip of sporangiophore, single terminal sporangium is produced.
8. Sporangium is differentiated into lower sterile columella and upper fertile sporangial sac.
9. Sporangiospores are born endogenously in the fertile sporangial sac.
10. On maturity sporangial wall breaks into the fragments and columella hangs above the sporangiophores, this appears like an umbrella or inverted bowl.
11. Spores are non-sticky and blown to a wider area in the air.
12. Spores are non-motile (=aplanospores).

Economic importance

1. R. stolonifer is a facultative parasite over mature fruits and vegetables.
2. It is the source of
   1. Fumaric acid
   2. Lactic acid
   3. Cortisone (=steroid)
3. Some species cause "mucoromycosis" in human.
4. It is a common contaminant in microbial laboratories.

Rhizopus growing in habitat

Rhizopus stolonifer (Microscopic view)

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Content first created on 30-11-2022
last updated on 10-12-2022