Cytokinin and auxin effects on survival and rooting of Eucalyptus pellita and E. grandis × E. pellita cuttings

Abstract

Cytokinin and auxin formulations were assessed for propagating cuttings of two tropical eucalypts, Eucalyptus pellita and E. grandis × E. pellita. Foliar sprays of 0.44 mM benzyl adenine (BA) increased cutting survival but also reduced the percentage of cuttings that formed roots. Indole-3-buytric acid (IBA) at 7.8 mM increased the percentage of E. pellita cuttings that formed roots but did not significantly affect rooting of E. grandis × E. pellita. A higher IBA dose, 39.4 mM, greatly increased the number of adventitious roots per rooted cutting in both eucalypts but it reduced cutting survival. Cytokinin application is not recommended for E. pellita and E. grandis × E. pellita cuttings but a low auxin dose, 7.8 mM, is recommended for propagating E. pellita cuttings.