Applications of gamma rays irradiation and marker assisted selection for improving of bacterial leaf blight resistance rice

Mutation technique is very effective for improving main agronomic characteristics such as yield, quality and resistance to diseases and pests. It is well-known not only in worldwide but also in Vietnam. In this study, the application of irradiation techniques and biotechnology in mutant rice breeding has focused on some major traits, such as high yield, short duration, good quality and bacterial leaf blight resistance. BT62 dry seeds (carrying Xa7, Xa21 genes) were irradiated with 300 grey of Cobalt-60 gamma rays. M1 to M5 generations of this variety were using for evaluation of mutant characteristics in the field, inoculation of bacterial leaf blight in the green house and marker assisted selection to select elite lines which were resistant to bacterial leaf blight resistance. The results showed that eight promising mutant lines of M5 generation retained as short duration, good quality, bacterial leaf blight resistance as original varieties but they have the higher yield than the original ones. These promising mutant lines are suggested for further evaluation. (author)