CHEMICAL PROPERTIES OF THE TROPICAL BAMBOO CULMS: NATURE OR NURTURE? INSIGHTS FROM <em>GIGANTOCHLOA</em> <em>SCORTECHINII</em>, <em>DENDROCALAMUS</em> <em>PENDULUS</em> AND THEIR HYBRID SPECIES IN PENINSULAR MALAYSIA

Abstract

The most sought–after timber bamboo species in Peninsular Malaysia, Gigantochloa scortechinii (Buluh semantan, GS), is directly harvested from forests due to a lack of large-scale plantations. GS was confused with its hybrid species (×Gigantocalamus malpenensis, GM), resulted from natural hybridisation with another wild common species, Dendrocalamus pendulus (Buluh akar, DP). This study assessed the similarity and distinctiveness of chemical constituents in DP, GM and GS. On the basis of hybrid intermediacy, we assumed that a chemical property is likely to be heritable if its level in GM is intermediate between those of DP and GS. Culms of all species were collected from the logged-over forests in Perak. Culm dimensions, density and moisture were measured for each species. Based on the Technical Association of the Pulp and Paper Industry (TAPPI) standards of testing methods, the contents of cellulose, hemicellulose, lignin, ash and solvent extractives were analysed for 18
samples (six for each species) using ANOVA and Tukey’s test. DP culms are the longest and they have significantly longer (p < 0.05) internodes, smaller diameter and thinner walls than those of GM and GS. GS has a relatively high cellulose content (58.38 ± 1.19%, crystallinity index = 78.30%). Cellulose, hemicellulose and lignin were significantly (p < 0.05) different between DP and GS by 6.31%, 5.70% and 6.27%, respectively. Whereas, those of GM were intermediate, implying that they are heritable characteristics. Lignocellulose contents are rather consistent within each of these species, that is low relative standard deviation (RSD), while ash content and solvent extractives exhibit higher intraspecies variation, possibly attributed to stronger environmental influences than genetics. Based on its chemical properties, we suggested that prospective biomaterials for biofuels, chemicals, pulps and fabrics can be derived from GS.