Induction of mutations with regard to some morphological and grain characteristics in oryza sativa var indica and oryza sativa var javanica varieties of rice oryza sativa
Bulletin of the Botanical Society of Bengal 33(1-2): 51-56
Effects of 2-6 h EMS (ethyl methanesulfonate) treatments of presaked seeds of rice (O. sativa L.) cultivars Dahar Nagra and Baok to induce morphological and genetical changes were studied. EMS-treatment significantly reduced the germination and seed fertility in the M1 but recovery occurred in M2. Differences in the mean values between treated and control for heading duration and 1000-grain weight was not significant in M1 and M2 generations. The treated population had higher 1000 grain weight than the control. Frequency and spectrum of chlorophyll, morphological and grain-type mutations were studied in the M2 generation. The induced morphological mutants included dwarf, extreme dwarf, tall, early, late, non-lodging, maximum tillering, minimum tillering, sterile, narrow leaf and narrow stem. Grain-size mutants varied from long to coarse and small-grain types. A wider spectrum of mutations was induced in Dhar Nagra than in Baok and the frequency and spectrum of mutations was enhanced by 6 h treatment which linearly receded the decrease in treatment duration. Among the morphological and grain-type mutants reported in the present study the dwarfs, early, non-lodging and the fine-grain types presumably appear to be useful for breeding.