KARAKTERISTIK SERAT KAYU HIBRID Acacia auriculiformis x Acacia mangium SEBAGAI BAHAN BAKU PULP

Abstract

Acacia auriculiformis x Acacia mangium hybrid (Aa x Am) is a promising Acacia hybrid for pulp. Wood properties of the hybrid have been reported for their physical and chemical characteristics, but the fiber characteristics have not been investigated. This study was aimed to investigate the fiber characteristics of the hybrid. Wood samples were collected from three years old of Aa x Am hybrid trees planted in a hybrid seed orchard. For comparison, wood sample from other three species: A. mangium x A. auriculiformis hybrid (Am x Aa), A. mangium and A. auriculformis on the same age, planted in the orchard were also collected. The wood sample was prepared from a slice which was put into a bottle containing a combination of acetic acid and hydrogen peroxide (perhidrol) in 1:20 (v/v) for observing fiber characteristics. The results showed that in general the fiber characteristics of Aa x Am hybrid were comparable to those of three comparison species. The average fiber dimensions were intermediate between the two parents: 0.85 mm, 16.09 µm, 12.56 µm and 1.7 µm for fiber length, fiber diameter, fiber lumen width and fiber wall thickness, respectively. The derived values were variable to three comparison species, with the Muhlstep ratio and flexibility coefficient were slightly lower than those observed in Am x Aa hybrid. Based on the level of fiber quality for pulp, the Aa x Am hybrid was classified as level II, the same level as A. mangium and hybrid Am x Aa.

Wood Anatomical Structures of Tropical Acacias and its Implication to Tree Breeding

“…The fiber dimensions of the wood from the four Acacias as used in this study were previously reported and the value is presented at Table 2 [25]. Except for the fiber length, all fiber dimensions were significantly different (p<0.05) among the four Acacias.…”

“…Although a direct comparison between these two studies is not appropriate because of the differences in the sites and stand, it revealed that the age likely affected the change of fiber dimension of Acacia species. [25] Remark: average numbers followed by the sane letters in a column were not significantly different at the level of Based on the fiber dimension properties as mentioned above, the four Acacias are classified as the short fiber tropical species (fiber length ≤ 0.900 mm). The value of fiber dimension is important to assess the suitability of the wood for the type of end-product, especially for pulp and paper.…”

“…This HSO was established for producing Acacia hybrid seed as the result of the inter-specific out crossing between A. mangium and A. auriculiformis. To optimize the crossing rate, two mother tree species of A. mangium and A. auriculiformis, with a total around 12,000 trees, were planted in the same area using an alternating rows design with an initial spacing of 3 m x 1 m: 3 meter between rows species and 1 meter within row species [25]. The seed of two mother tree species planted in the HSO were collected from selected plus trees in respective first-generation seedling seed orchard.…”

“…The A. mangium and AM x AA hybrid sample tree were selected in the A. mangium's rows, while for the A. auriculiformis and AA x AM hybrid were selected in A. auriculiformis's rows. To detect the hybrid status, all of the Acacia hybrid trees selected based on their morphological markers were then verified using molecular marker before collecting wood sample [25]. Three sample trees for each of four Acacias species were selected for wood sample collection.…”

Anatomical properties of branches and twigs mangrove woods

“…The S. caseolaris branch has the highest Flexibility Ratio (FR) of 0.29 and the A. marina branch has the lowest 0.23. According to Sunarti et al [25] wood as a raw material with a lower Muhlstep number value will produce better pulp quality, the density of the pulp sheet produced will be better with better strength properties. A high coefficient of flexibility will have a thin wall thickness and easily deform so that it will produce pulp sheets with better strength.…”