The main control practice of Leifsonia xyli subsp. xyli (Lxx) in sugarcane is to heat-treat cane 15 cuttings used as planting material in an attempt to eradicate the bacterium. A real time 16 quantitative PCR (qPCR) protocol specific for Lxx was developed to assess the effectiveness of 17 this practice. Primers were designed from the sequence of an Lxx-specific gene and detected as 18 were collected from plant canes with low bacterial titers whereas in the second they were 22 collected from first-ratoon canes with higher titers. Lxx was quantified in leaves by qPCR 90 23 *Manuscript Click here to view linked References 2 days after planting. Lxx was detected at variable titers in 50 to 90% of the plants, indicating that 24 the heat treatment was not effective in eradicating Lxx from all plants. However, in the second 25 experiment the bacterial population was reduced, as the median number of Lxx cells was lower 26 compared to the non-treated control. In the case of SP70-3370, the treatment also reduced the 27 number of Lxx-infected plants considering the pooled data of the two experiments. The results 28 indicated that although the heat treatment did not completely eliminate the bacterium, it can be 29 used to reduce the pathogen population in plants propagated from canes with high bacterial titers. 30