Progeny Test of Shorea Leprosula as Key Point to IncreaseProductivity of Secondary Forest in Pt Balik Papan ForestIndustries, East Kalimantan, Indonesia

Shorea leprosula is one of the valuable species in the tropical rain forest and it has distributed widely in the lowland tropical rain forest with altitude up to 700 m above sea level. Due to decreasingthe number of forest area, it will affect the sustainability of S. leprosula in the tropical rain forest. Ex situ conservation through establishment of S.leprosula progeny test was one of the best way to evaluate the best genotypes of mother trees (family) in order toset up the breeding program and produce the improved planting stock materials for forest rehabilitation.The research was conducted in Balik Papan Forest Industries (BFI), a Forestry Company in East Kalimantan, Indonesia. A total of 60 open pollinated plus trees have been selected and used for the genetic materials of the study. The progeny test wasplanted in 2009and laid out in randomized completely block design (RCBD), 4-tree line plots/family with 3 replications and at a spacing6 x 3 meter. The result of research showed significant in both high and DBH variable at tα Family5%. The biggest and lowest of DBH growth were the family no. 51018 (2.78 cm.year-1 of mean annual increment/MAI) and family no. 51052 (1.66 cm.year-1 of MAI). Moreover, the highest and the lowest of height growth were family 51030 (2.6 m.year-1 of mean annual increment/MAI) and 51003 (1.5 m.year-1 of MAI) respectively. Families selected in this research could be used to produce the improved planting stock material for rehabilitation insecondary tropical rain forest