Result of Breeding New Two-Line Hybrid Rice Combination TH8-3

Abstract

The new two-line hybrid rice variety TH8-3 (T7S/R3)has been selected and tested by the Devision of Hybrid Rice Technology of HUA. The female line T7S is a TGMS line with Critical Sterility Inducing Temperature (CSIT) at 240C, has duration from seeding to heading 82-85 days with acceptable plant type. T7S can be multiplied in Spring season and hybid seed production in Summer season in the Red river delta. The male line R3 is the same male line used for TH3-3 hybrid. TH8-3 is a temperature sensitive hybrid variety, with short growth duration (105-110 days in Summer crop; 121-126 days in Spring crop); with high yield (5-8 t ha-1), good quality, resistant to lodging, diseases and pests, i.e. blast, sheath blight, bacterial leaf blight. TH8-3 is suitable for growing in the late Spring and early Summer crop seasons in the northern provincies of Vietnam. The technical protocols for female line multiplication and hybrid seed production of TH8-3 wereset up with the F1 hybrid seed yield of 2 -2.67 t ha-1