Summary
Artificial heterokaryons between carotene mutants ofPhycomyces blakesleeanus Bgff. have been prepared by squeezing cytoplasm out of two different mutant sporangiophores and allowing the fused droplets to regenerate.
These heterokaryons are used to study the distribution of nuclei at different stages of the asexual life cycle. It is proposed that the nuclear ratio is constant in all parts of the mycelium, sporangiophores and sporangia, and that random samples of nuclei are packaged into spores. This model permits quantitative predictions regarding the proportions of phenotypes in the asexual progeny and these predictions are corroborated by experiments. The nuclear ratio remains constant during repeated mycelial transfers.
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Heisenberg, M., Cerdá-Olmedo, E. Segregation of heterokaryons in the asexual cycle ofPhycomyces . Molec. Gen. Genet. 102, 187–195 (1968). https://doi.org/10.1007/BF00385973
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DOI: https://doi.org/10.1007/BF00385973