Colchicine-resistant mutants of Chlamydomonas reinhardi

Five colchicine-resistant mutant strains of Chlamydomonas reinhardi have been isolated. In colchicine-free medium they all have abnormally long cell doubling times and tend to occur within palmella envelopes, rather than as free-swimming cells. Zygote germination of all the mutants is abnormal, but crosses with wild type suggest that resistance is in each case due to a Mendelian mutation. It is suggested, though not proved, that the mutations may affect microtubular structures.