Introgression of Sub1 QTL into an elite rice (Oryza sativa L.) variety Jyothi through Marker Assisted Backcross Breeding

Sub1 QTL for submergence tolerance was introgressed into the most popular rice variety of Kerala, Jyothi, from the donor parent Swarna-Sub1 using Marker Assisted Backcross Breeding. For the foreground and recombinant selection of the F1 as well as the backcross populations, molecular markers linked to Sub1locus and markers flanking the locus, respectively, were used. Markers unlinked to the Sub1locus were used for background selection among the selected progeny. Selected BC2F2progeny were found to have recurrent parent genome recovery in the range of 83.4 - 85.9%. The size of the introgressed donor fragment into the selected lines was estimated to be 1.6 - 5.6 Mb. Analysis of the selected BC3F2progeny showed the recipient parent genome recovery varying from 92.1 - 98.9% with the introgressedSub1 donor fragment size ranging from 4.2 - 5.6 Mb. The survival score of the developed BC2F2 and BC3F2 lines were same as that of the donor parent, confirming the introgression of Sub1 QTL.