Anatomical Characteristics of Reaction Wood in Tropical Softwood Species Grown in Indonesia

다국어 초록 (Multilingual Abstract)

Pinus merkusii and Agathis loranthifolia woods are common raw materials for lumber, wood panels, musical instruments, pulp, and paper. However, compression wood commonly occurs in the stem wood of fast-growing species, such as Pinus, Agathis, and Podocarpus and also caused trouble in the industry when mixed with the normal wood. Therefore, it is essential to identify the occurrences of reaction in commercial wood to increase efficiency in utilizing Pinus merkusii and Agathis loranthifolia woods. The present study observed and compared the anatomical characteristics of compression (CW), lateral (LW), and opposite (OW) woods in the stem wood of Pinus merkusii and Agathis loranthifolia. The qualitative and quantitative anatomical characteristics were observed by optical and scanning electron microscopy, and the crystalline characteristics were analyzed with an x-ray diffractometry. In qualitative anatomical characteristics, CW of both species showed a gradual transition from earlywood to latewood in both species, circular tracheid shape, many intercellular spaces, irregular tracheid tips, helical cavities, and slit-like bordered pits. CW of Pinus merkusii showed an indistinct growth ring, while CW of Agathis loranthifolia showed a distinct growth ring. Helical ribs occurred only in CW of Pinus merkusii. LW and OW of both species showed similar qualitative anatomical characteristics. The quantitative anatomical characteristics of CW, LW, and OW in both species will be shown in the oral presentation.