OBSERVATIONS ON VERTICAL-DISTRIBUTION OF FUNGI ASSOCIATED WITH STANDING SENESCENT ACANTHUS-ILICIFOLIUS STEMS AT MAI-PO MANGROVE, HONG-KONG

The present study was carried out to investigate the higher fungi colo nizing the herbaceous mangrove associate Acanthus ilicifolius. This pa per reports part of an investigation to determine if there is vertical distribution of fungi on the standing plant. The Mai Po Mangrove, Hon g Kong is estuarine with great variations in salinity mainly due to th e influence of the Pearl River. Senescent and dead stems of standing A canthrus ilicifolius were collected from mangroves in Mai Po from Apri l to December 1992. The maximum tidal range observed was 2.6 m. A stra tified sampling strategy was employed to assess the vertical distribut ion on the standing plant. A total of 44 fungi were collected: 32 Deut eromycotina, 11 Ascomycotina and 1 Basidiomycotina. Very frequent spec ies were Acremonium sp.(55%), Colletatrichum gloeosporioides cf.(42.5% ), Phoma sp. (42.5%) Fusarium sp.,(25%), Tubercularia sp. (24.2%) and Phialophora sp. cf. (19.2%). Agerita sp., Corynespora cassiicola, Stac hybotrys chartarum, Trichoderma sp. and D82 were frequent, while the r emaining species were recorded at less than 10%. Vertical zonation of fungi colonizing the standing stems was observed. The apical portions were colonized by typical terrestrial fungi and the basal portions by marine species. This can be attributed to both the nature of the subst ratum and the degree of exposure due to tidal inundation.