Gibberellin A3 stimulates adventitious rooting of cuttings from cherry (Prunus avium)

We have examined the effect of exogenous gibberellin A(3) (GA(3)) on adventitious rooting of Prunus avium (cherry) cultivars Stella, F12/1 and Charger. We show that GA(3) pre-treatment of P. avium stock plants causes an increase in shoot growth rate and also improves the rooting of cuttings subsequently taken from the treated plants. Approximately 37% of cuttings from control shoots rooted, whereas the percentage rooting could be increased to 80% or more with GA(3) pre-treatment. The number of roots per rooted cutting was also increased by GA(3) pretreatment. The stimulation of adventitious rooting could be partially explained by the increase in shoot growth rate. Cultivar Charger responded better than the other cultivars to the lowest level of GA(3) treatment. In vitro cultures of cultivar Charger were also treated with GA(3). However, the stimulation of adventitious rooting was less marked than in the GA(3)-treated stock plants: percentage rooting increased from 70% to 85%. The results are discussed in the context of 'rejuvenation' effects of GA(3).