Development of New Drought Tolerant Breeding Lines for Vietnam Using Marker-Assisted Backcrossing

Development of drought tolerant high-yielding varieties is essential because increased areas are subject to drought in the Mekong delta, Vietnam. The purpose of this experiment was developed using IR75499-73-1-B as drought tolerant donor and OMCS2000 as a recipient parent basis of a phenotypic and molecular marker for BC 2 F 2 generation. Seven markers (RM219, RM201 RM105, RM23602, RM23877, RM24103 and RM328) were used for a idifying to drought tolerant. Primer RM23877 detected the highest number of lines as homozygous donor alleles (11 lines), followed by RM105 and RM201 (9 lines). The drought gene was introgressed into the new breeding lines. The plant height, number of tillers, and filled grain had positive correlation with yield/hill under drought stress. The lines BC 2 F 2 -45 and BC 2 F 2 -54 developed as drought tolerant, and gave high yield. This is an opportunity to improve breeding for high yield and drought tolerant rice varieties in Vietnam.