Molecular mapping of early vigour related QTLs in rice

Upland rice plays a major role in the sustainable food security of the country. Early vigour trait is important in the drill-sown rice for weed suppression as well as initial establishment. The IR64/Azucena was used as a reference population to identify Quantitative Trait Loci (QTLs) for early vigour related traits. The Simple Sequence Repeat (SSR) markers flanking QTLs in IR64/Azucena and other populations were used for validation in the new populations (BPT5204/A67 and BPT5204/Dodiga). Twenty-two QTLs distributed on chromosomes 1 to 6 were identified for different vigour related traits. The QTLs controlling germination were located on chromosome 1 in the region RM5-RM306 near to alpha-amylase genes which controls germination. The congruence of QTLs was observed on Chromosome 5 in the region RM87-RM334 for rate of germination, seedling dry weight and vigour index. RM253 (Chromosome 6) was associated with the shoot length at 10th and 14th day after sowing (DAS) with 9.6% and 10.1% contribution in BPT5204/A67. RM178 (Chromosome 5) was associated with shoot length (18%) and root length (11.2%) at 10th DAS in BPT5204/Dodiga.