The generation of mutants by irradiation with gamma rays is a
useful technique for improving function and conducting physiological and biotechnological studies.Mutant induction technology is avaluable tool for the development of new varieties by improving the tolerance of organisms to biotic and abiotic stresses. Indeed,induction and isolation of mutants has been widely used as a key technique for both strain improvement and the analysis of complex path ways(Fischer, 1998). Forexample,a
Haematococcus mutant was obtainedby treatment withUV,ethyl
methane sulfonate(EMS),and1-methyl-3-nitro-1-nitrosoguani-
dine (NTG)(Park etal.,2006)