Abstract:To determine the influence of the LsRGL1 gene on lettuce bolting, the S39 lettuce variety was used as the experimental material, and the LsRGL1 gene was cloned from the S39 lettuce variety using reverse transcription polymerase chain reaction(RT-PCR). The goal gene was silenced using a virus-induced gene silencing(VIGS) method with a tobacco rattle virus(TRV) vector. Methods of phenotypic observation, paraffin section, real-time fluorescence quantitative PCR(qPCR) and enzyme-linked immunosorbent assay(ELISA) were used to study the phenotypes, bud differentiation, relative expression levels of the LsRGL1 gene, and endogenous hormone mass fractions changes in the blank control group(without TRV vector), negative control group(injection of TRV1 empty vector and TRV2 empty vector in a mass ratio of 1∶1 ), and experimental group(injection of TRV1 empty vector and TRV2-LsRGL1 recombinant vector in a mass ratio of 1∶1). The results showed that after virus infection, the stem length of the experimental group was significantly larger than that of the blank control group and the negative control group, and the data of all traits in the experimental group were all greater than those of the two control groups. There was no obvious difference in the traits of the blank control group and the negative control group. The paraffin section results showed that the experimental group had begun bud differentiation, entering the reproductive growth period earlier than the control group. The qPCR analysis results showed that compared with the blank group and the negative control group, the relative expression level of the LsRGL1 gene in the experimental group was significantly downregulated with 50% more in the amplitude. The mass fractions of endogenous hormones gibberellin(GA3), abscisic acid(ABA) and auxin(IAA) in the experimental group were significantly higher than those of the control group, while the mass fraction of jasmonic acid(JA) was significantly lower. In summary, silencing the LsRGL1 gene could accelerate bolting in lettuce.