Rapid and pervasive occupation of fallen mangrove leaves by a marine zoosporic fungus.

摘要: Samples of leaves red mangrove (Rhizophora mangle) were incubated on an agar medium selective for pythiaceous oomycetes. Leaves trees above the water did not contain Marine oomycetes, principally Phytophthora vesicula, had colonized within 2 h leaf submergence, probably finding them by chemotaxis. The frequency occurrence P. vesicula in submerged reached 100% 30 submergence. By 43 most, if all, parts occupied, and surface treatment with a biocide indicated that occupied internally. Frequencies remained near through about weeks submergence then declined to 60% older (≥4 weeks) leaves. white (Laguncularia racemosa) also extensively after falling into column, but decaying turtlegrass (Thalassia testudinum) Ergosterol analysis standing crop living, non-oomycete (ergosterol-containing) fungal mass red-mangrove rise which been present senescent tree; ergosterol content was only 2% maximum concentration detected These results suggest oomycetes are predominant mycelial eucaryotic saprotrophs fall column live, die, decompose under conditions, eucaryotes make no substantial contribution decomposition.