Inhibitory effects of Acremonium sp. on Fusarium wilt in bananas

An endophytic fungus, strain Q34, isolated from Kandelia candel (L.) Druce showed strong in vitro antagonistic activity toward Fusarium oxysporum f. sp. cubense (foc) race 4. The crude extract of the strain inhibited the growth of foc race 4 and caused conidial deformation. In gas chromatography-mass spectrometry (GC-MS) analysis, the crude extract showed 18 main peaks. Three substances from the main peaks showed strong inhibitory activity against the growth of foc race 4. Moreover, the strain Q34 reduced the incidence of Fusarium wilt in banana plantlets under greenhouse conditions and in the field. This strain was identified as Acremonium sp. on the basis of morphology. These results suggest that strain Q34 is potentially useful for the biological control of foc race 4.   Key words: Fusarium oxysporum f. sp. cubense race 4, Acremonium sp., biological control, Fusarium wilt.