Assessement of the performance of rubber clones utilizing the selection index method

Abstract

An assessement study of two-year-old rubber tree clones (Hevea spp.) was conducted utilizing four selection indexes. The characters considered were yield, plant height, stem diameter, bark thickness and diameter of the latex vessels. In a hypothetical selection of the best clones, the expected genetic gain was estimated. The four indexes showed the same clones as superior, although the b_j values estimated were different in absolute and relative values. In selecting the best clones during the growth phase, genetic gain was not increased with inclusion of a large number of characters in the selection index. No advantages ware observed in utilizing the methodology of selection index over tandem selection or in utilizing the selection of two-year-old rubber trees.