THE POTENTIAL OF CHITOSAN IN SUPPRESSING GANODERMA BONINENSE INFECTION IN OIL-PALM SEEDLINGS

Abstract

This paper discusses the possible use of chitosan in controlling Ganoderma infection in oil-palm nursery. Research was conducted to determine the suitable concentration of chitosan in suppressing Basal Stem Rot (BSR) in oil-palm seedlings caused by Ganoderma. Three different concentrations of chitosantested were 0.5, 1.0 or 1.5% (w/v). In addition to this, a lower concentration (0.1%) was also evaluated at two different intervals of addition to the seedlings. The effectiveness of chitosan was measured through concentration of ergosterol (the fungal sterol) found in oil-palm roots, mean percentage of disease severity, percentage of bole tissue infection and possible isolationof Ganoderma on Ganoderma Selective Mediwn (GSM). Results showed the minimum concentration of chitosan; 0.5% (w/v) suppressed the fungal sterol to the minimum and scored the lowest percentage mean disease severity in comparison to other concentrations. However, there was no significant difference shown between all concentrations ofchitosan for bole tissue infection as no infection was noted. Ganoderma was successfully isolated from seedlings roots of all treatments except healthy control using GSM. Ganoderma-infected seedlings that were treated with chitosan (0.1%, w/v ) also showed slightly lower disease severity compared to seedlings pre-treated with chitosan and later infected by Ganoderma at the same concentration.