Starch RVA profile parameters of rice are mainly controlled by Wx gene

Quantitative trait locus (QTLs) mapping for rapid visco: analyser (RVA) profile parameters has been carried out by using a double haploid (DH) population derived from a cross between indica variety Zhai-Ye-Qing 8 and japonica variety Jing-Xi 17 and its genetic linkage map. The results indicate that the segregation of the RVA profiles:is continually distributed among the DH lines, and some DH lines show transgressive segregation for all the parameters, A major QTL, Wavy (Wx) gene on chromosome 6 which controls the amylose synthesis, has been detected significantly for 5 traits: hot paste viscosity (HPV), cool paste viscosity (CPV), breakdown viscosity (BDV), consistency viscosity (CSV) and setback viscosity (SBV), Therefore, the RVA profile parameters are mainly controlled by Wx gene. Other 3 and 2 QTLs have also been identified for BDV and SBV, respectively, and two of them share the same region on chromosomes 1 and 5, However, the peak viscosity (PKV) is controlled by a minor QTL on chromosome 12, qPKV-12.