DELLA-NAC interactions mediate GA signaling to promote secondary cell wall formation in cotton stem

Gibberellins promote secondary cell walls (SCW) development in plants, but the underlying molecular mechanism is still to be elucidated. Here, we employed a new system, the first internode of cotton, and virus-induced gene silencing (VIGS) method to address this problem. We found that knocking down the major DELLA genes via VIGS phenocopied GA treatment and significantly enhanced the SCW formation in the xylem and phloem of cotton stems.