Mini‐cutting technique application in Corymbia and Eucalyptus: effects of mini‐tunnel use across seasons of the year

Abstract

The forestry sector has been able to sustainably satisfy the increasing global demand for forest products, thereby positively impacting the economy, while mitigating climate change. It is therefore necessary to continue developing technologies to support vegetative propagation activities that consider the diverse genetic resources and their optimal production environments. This study aimed to investigate the influence of mini-tunnel use in the clonal mini-garden (MG) and greenhouse (GH) environments on the survival and rooting of mini-cuttings of three Eucalyptus species and a Corymbia species under subtropical climate conditions across the four annual seasons. A factorial experimental scheme was adopted with two environments for stock plants [MG with mini-tunnel (MGWT) and without mini-tunnel (MGOT)], and two rooting environments [GH with mini tunnel (GHWT) and without mini-tunnel (GHOT)]. We found that the use of a mini-tunnel did not influence mini-cutting survival, and all species exhibited superior performance during cold seasons. Eucalyptus mini-cuttings had high rooting under average temperatures of 23.9 °C (GHWT), which occurred in autumn. Conversely, the rooting of Corymbia mini-cuttings was enhanced in winter, in environments with average temperatures of 19.55 °C (MGWT and GHWT). Mini-tunnels altered the clonal production microenvironment, thereby enhancing adventitious rooting. For Eucalyptus, their use is recommended in the GH in autumn and winter. For clonal production of Corymbia, mini-tunnel use is recommended in both the clonal MG and GH.