Coppicing Abilities of Decapitated Elite Tree Trunks of Selected Acacia Species Genotypes in Mixed-Species Plantation

Abstract

Maturation-related loss in the shooting and rooting ability of a species through macro or micropropagation techniques has been a limiting factor in any forest tree improvement program. The rejuvenation capacity of mature elite trees of Acacia mangium, Acacia crassicarpa, Acacia auriculiformis, and Acacia aulococarpa was investigated by evaluating the sprouting ability of decapitated trunks. Thus, a total of 120 trees were selected based on their superior phenotypic characteristics from four provenance and five progenies of each species, and trunks of the elite trees were decapitated into two different height groups to induce coppicing from the collar and base of the trunk. Coppicing ability varies with species, provenance, progeny, and cutting height. A. auriculiformis was the easiest to produce shoots by having the highest shooting percentage (84%) and the number of shoots per trunk (13.5), followed by A. mangium (75%) and A. aulococarpa (40%). The total shoot number increased significantly with the increase in the height of the stumps. Data indicated that there is a possibility to rejuvenate matured cutting through coppicing in the natural environment. This study will help in the standardization of the stumping procedure for the rejuvenation of elite Acacia genotypes while simultaneously assisting in preserving germplasm through clonal propagation.