Among-family variations in growth traits, the stress-wave velocity of stems, and log characteristics of the first-generation Neolamarckia macrophylla (Roxb.) Bosser in Indonesia

Abstract

The growth traits (stem diameter at 1.3 m above the ground and tree height), stress-wave velocity of the stems, and log characteristics (taper and dynamic Young’s modulus of logs) were examined for 54 trees from 18 half-sib families planted in a seedling seed orchard of the first-generation Neolamarckia macrophylla (11-year-old) in Wonogiri, Central Java, Indonesia. The mean values for stem diameter and tree height were 20.2 cm and 20.0 m, respectively. The stress-wave velocity of the stems was 3.76 km s^－1. Meanwhile, the taper and dynamic Young’s modulus of logs were 0.57 cm m^－1 and 8.13 GPa, respectively. The heritability values of each trait were 0.412, 0.365, 0.101, <0.001, and 0.092 for the stem diameter, tree height, stress-wave velocity of stems, taper of logs, and dynamic Young’s modulus of logs, respectively, suggesting that the improvement of all traits is possible for the next generation, with the exception of the log taper. The 18 half-sib families could be classified into three groups for different potential uses based on the principal component analysis and cluster analysis results.