Molecular marker-assisted dissection of genotype x environment interactionfor plant type traits in rice (Oryza sativa L.)

A doubled haploid (DH) population of 123 lines from IR64/Azucena was used t o analyze the genotype x environment (GE) interaction for eight plant type traits in rice (Oryza sativa L.). The total genetic effects were partitione d into genetic main effects and GE interaction effects. These two kinds of predicted effects were used in mapping quantitative trait loci (QTLs). Four to nine QTLs affecting different plant type traits were detected. Results indicated that all common QTLs detected in both environments were controlle d by genetic main effects and some also by GE interaction effects. Some gen omic regions identified significant QTL in only one environment; some also showed genetic main effects. Those QTLs with genetic main effects could be used in marker-assisted selection across environments. For some other map r egions, QTLs were controlled by only GE interaction effects without genetic main effects. Those QTLs could be included in marker-assisted selection on ly tor specific environments. In most cases, the pairs of traits with a hig h genetic correlation shared more common QTL regions than those pairs of tr aits with a lower genetic correlation.