Fig. 4

Quantitative RT-PCR analysis of expression of GhCPD and GhDWF4 genes in cotton fibers treated with BL and Brz. Cotton bolls (9 DPA) were in vitro cultured in liquid BT medium without or with 100 nM 2, 4-epibrassinolide (eBL) or brassinazole2001 (Brz) at 30 °C in darkness for 3 h. Transcript levels of GhCPD and GhDWF4 were determined by quantitative RT-PCR, using GhUBI1 (EU604080) as a quantification control, and expression levels of the genes in the untreated samples (0 nM BL or Brz) were set to 1. Data were processed with Microsoft Excel. Mean values and standard deviations are shown from three independent experiments. Two asterisks represent there was very significant difference (P < 0.01) in gene expression level between the treated sample and the untreated sample (control). DPA, day post anthesis