Gamma-ray radiation and sodium azide (NaN3) mutagenic efficiency in rice
Akihiko Ando and Ricardo Montalván
Rice (Oriza sativa L.) cultivar IAC-1246 seeds were treated with 10, 15, 20 and 30 Krads of gamma-rays and sodium azide (SA) concentrations of 0.5, 1.0 and 5.0 mM to study their efficiency in inducing chlorophyll mutations. Combined treatments incremented the damages when compared to single treatments, especially for seedling height and M1 panicles fertility. Treatments with SA showed a higher frequency of chlorophyll mutations than the gamma-ray treatments, both in single and combined treatments. The gamma-ray spectrum was different for the various types of mutations, whether in individual or combined treatments. The SA efficiency was higher than that of gamma – rays at 1.0 and 5.0 mM concentrations and lower at 0.5 mM. On average, the additive effect of the mutagenic combinations was more evident than the frequencies of the mutations.