6 strains of norflurozon-resistant mutants of Chlamydomonas reinbardtii have been hybridized with a wild type individual

a cbn1-43 allelic mutant which lost the ability of synthesize chlorophyll b and an Arginine-dependent mutant respectively

and the tetrad analysis and random sampling was performed. It appeared that

on the mutants Nfr-4-Nfr-7

only have nuclear monogenic character for norflurozon-resistance

while on the Nfr-1 and Nfr-3 mutants

the norflurozon-resistant trait are determined by two non-linkaged genes. The result of self-crossing of norflurozon-resistant mutant indicated that

the resistant traits of Nfr-1 and Nfr-3~Nfr-7 are determined by a mutation on the Nfr-1 gene

and that of Nfr-4 is determined by another gene

Nfr-2.On the norflurozon-resistant mutants Nfr-1 and Nfr-3

a mutation of Nfr-3 gene is participated in the representation of resistant character

as well as the mutation of Nfr-1.