B,D,E transgenic clones with rolABC genes and wildtype plants were used as materials to construct binary standard curves of rol genes and β-actin gene with SYBR Green I fluorescent dye.After normalizing the influence of amplification efficiency with different primers in qRT-PCR,comparative Delta-delta Ct method was applied to develop suitable qRT-PCR method for analysising the expression of rolA,rolB,rolC genes in 5 tested tissues of B,D,E clones.The primary result showed that rolC expressed highest among 3 rol genes in tender stem,tender leaf,functional leaf and bark,rolA gene's expression in the middle level and mainly in tender stem,and rolB expressed lowest and mainly in root.