Lifecycle of Neurospora

A. Asexual reproduction in Neurospora:

a) By culture:

• Placing a fragment of the threadlike hyphae of a mycelium of the fungus on a suitable culture medium.
• Each hyphae is segmented and each segment usually contains more than haploid nucleus.

b) By conidia:

• Conidia helps in formation of new mycelia.

B. Sexual reproduction in Neurospora:

• Usually takes place by ascospore.
• Conidia acts as male gamete and trichogyne acts as female organ.
• When a conidium from one mating type contacts a receptive trichogyny of the opposite mating type, it moves into the fruiting body, dividing mitotically as it goes alone, and fertilizes a no. of maternal nuclei.
• Diploid sexual zygotes are thus formed that are each enclosed in an oval ascus sac.
• The zygote in each ascus immediately divides meiotically to yield 4 haploid cells which then under goes a single mitosis to furnish a total of 8 haploid cells per ascus called ascospore.
• The ascospore is haploid and grows directly into a new mycelium.