Studies on Anatomical and Physico-Mechanical Properties of Candidate Plus Culms (CPCs) of Dendrocalamus strictus for Planting Stock Improvement Programme

Abstract

Five candidate plus culms (CPCs) of about 2-year-old Dendrocalamus strictus (namely 16, 17, 21, 55 and 110) were collected from Sirsi, Karnataka, India, for investigations on anatomical, physical and mechanical properties. Various morphological (inter-nodal length, culm diameter and culm wall thickness), anatomical (fibre length, fibre diameter, fibre lumen diameter, fibre wall thickness and vascular bundles), physical (moisture content and specific gravity) and mechanical (fibre stress at elastic limit-FS at EL, modulus of rupture-MOR and modulus of elasticity-MOE) properties were evaluated for inter-comparison among the CPCs. Among all the CPCs, specific gravity was maximum in CPC 55 and minimum in CPC 17. A comparison of different properties was carried out at 2^nd and 4^th internode for all the five CPCs. The results indicate that the internodal length was lower in 2^nd than 4^th internodes with maximum and minimum values observed in CPC 55 and CPC 16 respectively. The culm diameter and culm wall thickness was higher in the 2^nd internode than 4^th internode. The maximum value of culm wall thickness was observed in CPC 110 and minimum in CPC 21 whereas culm diameter was maximum in CPC 16 and minimum in CPC 17. The fibre morphology did not show significant variation between 2^nd and 4^th internode among all the CPCs.

However, the number of vascular bundles remained more in 4^th internode of all the CPCs compared to 2^nd internode. While FS at EL was maximum in CPC 55, the minimum corresponding values were found in CPC 110. Similarly, the MOR was maximum in CPC 55 and minimum in CPC 110. The maximum value of MOE was observed in CPC 55 while minimum values was in CPC 16. The data analysis shows that CPCs 55 having superior strength properties is comparatively more suitable for structural applications. CPCs 16 showed most of the anatomical parameters in the higher range and may be utilized for general applications including pulp and paper. The data generated on CPCs may be of use for bamboo improvement program and bamboo plantations which can produce quality product.