Sprouting and rooting ability of the plus trees of Eucalyptus pellita, E. brassiana and its hybrid in Wanagama, Indonesia

Abstract

The demand for eucalypts has greatly increased since they are raw materials for timbers, plywoods, pulp and papers, and essential oil production. This study aimed to select the plus trees and determine the sprouting and rooting ability of E. pellita, E. brassiana, and their hybrids in Wanagama. Plus trees selection and girdling were conducted in December 2019. Cuttings were picked from the 3rd-4th nodes of sprouting at 8-10 cm in length. A completely randomized design was applied in a factorial experiment with three levels of Indole Butyric Acid (IBA) (100, 1000, and 4000 ppm) and two types of media (media 1: sand, rice husk charcoal and cocopeat (2:2:1), media 2: sand, topsoil and dung-fertilizer (2:2:1)), with ten replications. Results selected a total of 53 plus trees candidates (29 of E. pellita, 12 of E. brassiana, and 12 of hybrid). E. pellita is the best in sprouting ability (100% survival; 41-60 shoot/trees, 127-161cm shoot length, 0.53-0.57cm shoot diameter, and 194-252 leaves/shoot). Cuttings of E. pellita treated with 100 ppm IBA gained the highest survival and leaves production (96%-100%; 14-16 leaves), followed by E. brassiana (52%-66.67%; 7 leaves) and the hybrid (4% to 8.33%; 3-4 leaves). These results may contribute to arranging better strategies for mass production of selected eucalypts.

Effect of Continuous Planting on Tree Growth Traits and Growth Stress in Plantation Forests of Eucalyptus urophylla × E. grandis

“…(2) forests II and III sprouts grow from the root base, and as trees respond to environmental factors (light, wind, and slope) and forestry factors (planting density, interplanting, pruning), growth strain gradually accumulates; or (3) forests II and III may have formed cells characteristic of tension wood, i.e., a gelatinous layer, at sites of high strain eastward and northward, and the anatomical characteristics and chemical properties of these cells influence the magnitude of growth strain [44]. The accumulation of phenolic and allelopathic factors in soil may also account for rising growth stress in continuous planting [33].…”