Relative qPCR values of St1A, St2A , St2B , St3A and St3B transcripts in sorghum GA06/18 and Sila plants inoculated with S. turcica , 24 hpi. Water treatment was used on respective genotypes as a control. Error bars indicate standard deviation between three biological replications. * Indicates a significant increase (P < 0.05) compared to control levels. Primer used listed in Additional file 2.