INCIDENCE AND SPATIAL ANALYSIS OF ROOT ROT OF <em>ACACIA</em> <em>MANGIUM</em> IN INDONESIA

Abstract

IRIANTO, R. S. B., BARRY, K., HIDAYATI, N., ITO, S., FIANI, A., RIMBAWANTO, A. & MOHAMMED,
C. 2006. Incidence and spatial analysis of root rot of Acacia mangium in Indonesia. Root rot caused by
Ganoderma spp. is a serious concern in commercial plantations of Acacia mangium in Indonesia. This study
surveyed root rot incidence and spatial arrangement in commercial plantations and trials. In second rotation
commercial plantations in Sumatra and Kalimantan, root rot incidence was recorded between 3 and 28%
in trees aged from three to five years old. The compartments surveyed in Riau province and East Kalimantan
had significantly higher root rot than South Sumatra. In a progeny trial of A. mangium in Java, root rot
incidence was surveyed twice, when trees were eight and again at nine years old. Root rot incidence was
about 7 and 13% respectively. Spatial analysis by distance indices (SADIE) revealed that infected trees were
randomly distributed at the first time point but tended to become aggregated by the time of the second
survey. This highlights the probability of vegetative spread of the fungus after initial introduction to the
site. Assessment of root rot incidence on the basis of A. mangium provenance did not reveal any statistically
significant differences.