FIRST REPORT OF POSTHARVEST DRY ROT OF RAPHIA HOOKERI FRUITS CAUSED BY XYLARIA FEEJEENSIS
D.O. Esiegbuya, F.I. Okungbowa, E.A. Oruade-Dimaro, C.E. Airede
Raphia hookeri palm is cultivated in Nigeria and other parts of the world for its economic products ranging from building and construction materials to local beverage. The plant is propagated only by seed. R. hookeri-induced dry rot of palm fruits, a storage and field disease, was found to be associated with Xylaria feejeensis, Penicillium dierckxii, Botryodiplodia theobromae, Aspergillus niger and Trichoderma sp. A total of 309 seeds were examined and 17.48, 23.95 and 27.18% were found to be affected by the disease after two, four weeks and three months of storage, respectively. When healthy fruits were inoculated separately with the various fungi according to Oruade-Dimaro (1989) only X. feejeensis produced disease symptoms (dryness and flaky nature of the entire fruit, affecting the testa and embryo). Symptoms began with the growth of a mycelial mat on the fruit scales which gradually penetrated the mesocarp, forming a weft of mycelium surrounding it. The Commonwealth Mycological Institute (UK) confirmed the identity of the fungus by processing a partial ITS DNA sample of the organism followed by sequencing (IMI No. 501772). Analysis of the sequence showed top matches at >99% identity to the ITS sequences reported from X. feejeensis (Hsieh et al., 2010). This is apparently the first time that X. feejeensis has been isolated from Raphia palm and the first report of dry rot of Raphia palm fruit caused by X. feejeensis.