IMPROVING SUBMERGENCE TOLERANCE OF VIETNAMESE RICE CULTIVAR BY MOLECULAR BREEDING

Abstract

Submergence stress has caused by climate change is the major hindrance to enhancing rice production of Vietnam. In this study, we have evaluated the levels of submergence tolerance ability of the imported rice cultivars under the 4 different field trials. Among these, IR64-Sub1 exhibits the highest submergence tolerance with stable and high yield, and was used as a donor plant, while Bacthom 7, an elite Vietnamese rice cultivar was used as the recipient plant. In molecular markers study, we have used closely linkage markers with Sub1, flanking markers Sub1, and unlinked marker to Sub1 for the foreground, recombinant and background selections in the backcrossing generations between the donor and the recipient plants. In BC₃F₁ generation, the individual plant number 116 has carried QTL/Sub1 and retained the highest genetic background of the recipient parent up to 98.6%. The newly improved rice line may be useful for growing in the flooding areas of Vietnam to cope with the climate change.