Strigolactones (SLs),present in a wide variety of plant species,have been recently recognized as plant hormones.in the shoot,they suppress the outgrowth of preformed axillary buds (reviewed by Brewer et al.,2013);they are negative regulators of adventitious root formation (Rasmussen et al.,2012) and positive regulators of shoot secondary growth (Agusti et al.,2011).