Further report on the incorporation of the rice blast durable resistance into hybrid rice.

By crossing two durably resistant cultivars (Sanhuangzhan 2, Sanluzhan 7), and two resistant cultivars (Wai xuan 35, Aisanluzhan), with two popular sterile lines susceptible to rice blast (Guang A,Bo A), their hybrid rice combinations were studied with respect to qualitative resistance, quantitative resistance and field resistance in different blast conducive areas. Results indicated that the combinations with durably resistant donor showed the same durably resistant characteristics as correspondingly durably resistant cultivars. Quantitative resistance and field resistance in different blast conducive areas could be as indicators of durability of resistance. Quantitative resistance was closely related to field resistance in different blast conducive areas, and might be an important indicator of durable resistance to blast. These results suggested that it would be possible to breed for durable resistance to rice blast by means of selecting quantitative resistance which could be tested under artificial inoculation in greenhouse.