CHARACTERISTICS OF EPIDERMAL CELLS IN RALATING TO TAXONOMY AND QUALITY OF RATTAN CANES

Abstract

This paper is a detailed analysis emphasizing on the epidermis of rattan canes. The imformation was taken from the final report on “Anatomical Investigation of Javanese Rattan Canes as a Guide to their Identification,” submitted to BIOTROP, Bogor, Indonesia, by Siripatanadilok, S. (1974). In the report, 25 species of 5 genera (Calamus, Ceratolobus, Daemonorops, Korthalsia and Plectocomia) of Javanese rattan canes were studied anatomically. Only the figures of epidermal cells both from longitudinal and transverse sections were copied and also restudied from the available specimens.

Generally, epidermal cells are composed of three main components : cuticle or siliceous layer, cell wall and void or lumen.

The siliceous layer, which is non - epidermal substance, is normally found cover the outermost surface of the epidermis. The thickness of this layer is varied, however, half of the species studied lack siliceous layer. Some species of the genus Calamus which lack the siliceous layer show highly reflective bodies. These are the bodies siliceous like substance with more reflected property plugged at intercellular spaces. They are of different shapes are triangle, ovate and star shape. The epidermis of the spicies of genus Korthalsia, which also bare of siliceous layer, are serrated like surface and are always fastened with the epidermis of a leaf sheath making the cane looking dirty.

The outer wall thickness of epidermal cells is conspicuously different. It can be classified into 2 categories; the outer wall thickness is thicker than the height of its lumen, and the outer wall thickness is less than the height of the lumen. The shape of the lumens is also varied which can be categorized into oblong, rectangular, ovate, oval, narrow column irregular and ovate which specifically. located at the base. The height and width of the epidermal cells are also different between the species. It is found that the correlation between the size of the canes and the parameters, viz, height (H), width (W) and the outer wall thickness (T) of the epidermal cells are small.  The correlation coefficients are as follows : r (H)= 0.4082, r (W) = - 0.1038 and r (T) = 0.1058.

The epidermal cells are a strong taxonomic importance which can be used along with the other cane characteristics to identify the cane in to species. The epidermal cells, moreover, can be very well related to the cane quality.  In the presence of siliceous layer make the cane look shiny. The siliceous layer of some species are firmly fixed which will not be loosened when the canes are bent. This will upgrade the cane in the trade. Both the siliceous layer and the highly reflective bodies are somewhat the devices for protecting the cane from fungi and microorganism. The thickness of the outer wall of the epidermal cells is also a very important component in controlling the strength of the epidermis. The height and width of the epidermal cells also impart to the epidermal strength, that the long narrow epidermal cells, as a column like, will give higher wall material per unit area of the epidermis. As the principle the cel1s with higher cel1 wall matterial will show the greater strength. In utilization of rattan canes, therefore, those epidermal characteristics will. be very important parameters which is necessary for rattan cane grading.