Rapid and high-precision marker assisted backcrossing to introgress the SUB1 QTL into the Vietnamese elite rice variety

Submergence stress regularly influences about 15 million hectares of rice growing areas in South and Southeast Asia. Vietnam is one of the most vulnerable countries affected by submergence stress in Asia. Submergence caused by typhoons and floods is one of the major reasons for rice production losses in this country. A major quantitative trait locus (QTL) on chromosome 9, SUB1, has provided the opportunities to apply marker-assisted backcrossing (MABC) to develop submergence tolerant for an elite variety that is popularly grown in Vietnam. Improving rice tolerance with submergence is vital to minimize the risks from submergence stress. In this study, we reported a successful application of MABC method to select a line number 19 in BC2F1 populations that has genetic background up to 89.8%.