Growth Variation of Swietenia macrophylla King. Progeny Trial at 18 Months of Age in Trenggalek East Java

Swietenia macrophylla King. as known as wide leaf mahogany is a type of exotic species from Latin America that is common planted in Indonesia. This species is widely cultivated in several regions in Indonesia due to the high demand for carpentry timber. Therefore, to meet the high demand of wide leaf mahogany wood, the development of plantation forests of S. macrophylla with high productivity is very much needed. Development of plantation forests with high productivity requires the support of improvement seeds. Therefore, this study was conducted to determine the survival rate, growth variation between land race and between mother trees of 18 months old of S. macrophylla progeny trial. This progeny trial at the end of the selection can be converted into a seedling seed orchard (SSO) to produce the improvement seeds. Incomplete Block Design with two factors, i.e. land race (5 levels) and mother tree (50 levels) was used in this study. The results of the analysis showed that the survival rates of plant was significantly different between the land race but not among the mother trees. The average of survival rate of this species is only 71.58%, due to the landslide during the rainy season, burnt during the dry season and also exposed to stem borer attacks. Growth parameters (height and stem diameter) were significantly different between land race and mother tree. It showed that the Bondowoso land race exhibited the best performance of height and stem diameter, respectively 151.55 cm and 21.97 mm. The best mother tree in terms of growth (height and stem diameter) were exhibited on 19 individual tresses, with a range from 130.38 to 171.64 cm for height character and from 20.46 to 26.47 mm for stem diameter character.