In previous studies, we reported that a QTL for 1000-grain weight (TGW), qTGW3 was located in the interval between RM60 and RM523 (1.2Mb) on chromosome 3 using advanced backcross lines derived from a cross between Oryza sativa ssp. Indica cv. Milyang 23 and O. glaberrima. The O. glaberrima alleles at this locus increased TGW and GL in the Milyang 23 background. To further confirm and narrow down the position of the QTLs on chromosome 3, twenty lines with different O. glaberrima segments in the target region were selected. Twenty lines were evaluated for seven agronomic traits including 1,000 grain weight and grain length and also genotyped with ten SSR markers. Sixteen lines(A, B, C groups) with the O. glaberrima segment flanked by SSR markers, RM60 and RM7332 displayed significantly higher values than Milyang 23 in TGW and GL whereas four lines(D, E groups) without the O. glaberrima segment displayed no difference in TGW and GL. The result indicates that two QTL, qTGW3 and qGL3 are located near RM60 and RM7332.

• Ju-Won Kang(Department of Agronomy, Chungnam National University)
• Dong-Min Kim(Department of Agronomy, Chungnam National University)
• Yeo-Tae Yun(Chungnam Agricultural Research and Extension Services)
• Hyun-sook Lee(Department of Agronomy, Chungnam National University)
• Sang-Nag Ahn(Department of Agronomy, Chungnam National University) Corresponding Author