The growth and genetic potentials of gempol (Nauclea orientalis L.) as shading trees in urban landscapes

Abstract

Gempol (Nauclea orientalis L.) is a fast-growing species with a wide crown and large diameter. This native species has the ability to replenish soil fertility and to control erosion and may be integrated in urban landscapes for genetic conservation purposes. However, the ecological function of the species as well as the genetic potentials of this species have not been investigated. This study aimed to assess the growth performance and to evaluate the genetic potentials of gempol by utilizing the progeny test stand that was established in 2011 using a Randomized Complete Block Design (RCBD). The area was divided into 10 blocks in which each block was represented by 49 families planted using 4-tree-plot replication. The observation showed that as much as 67% of the trees had a straight stem form with the average score of 4.38. The diameter ranged between 9.17 – 14.23 cm, with a total height that ranged 5.90 – 8.60 m and a crown diameter with a range of 2.06 – 3.32 m. Depending on the traits, the heritability varied between low to high. Clear bole height performed the highest heritability with a value of 0.60 (family) and 0.52 (individual). A Crown diameter indicated a moderate positive correlation with a diameter degree of 0.328 and denoted a strong positive correlation with a total height degree of 0.798.