GROWTH OF SEVERAL RUBBER CLONES FOR TIMBER PRODUCTION

Abstract

LOKMAL, N., MOHD ZAKI, A., FARAH FAZWA, M. A., SUHAIMI, W. C., AZMY, Y., ZAKARIA, I., TAN, H.,
KHOO, S. K. & WAN-AKIL, T. A. 2008. Growth of several rubber clones for timber production. The study
was aimed at evaluating the growth behaviour of selected existing rubber clones under forest plantation
management to produce timber. The clones were initially developed under intensive agricultural system to
produce latex. We observed growth performance of seven-year-old rubber plantations at Bukit Hari Forest
Reserve and Sungai Buloh Forest Reserve, Selangor. In both sites clone PB 235 had the greatest height
and diameter. All clones performed better under lower density (600 trees/ha) plantation compared with
the higher density (900 trees/ha). Effect of clones was significant in individual as well as in the combined
analyses. Interaction between clone and site was highly significant but all clones maintained the same
ranking across sites. Clone by density interaction was not significant and coefficients of variation of clonal
materials were lower than clonal seedlings.