cast-off mangrove seedlings form a significant contribution to the 

 estuarine productivity of south Florida. 



It was found that the role of fungi in the degradation of red 

 mangrove seedlings appeared to be as invaders of the protective 

 external tissues. In injured seedlings, bacteria and protozoa entered 

 the pith tissues via the wound and rotted them. Both injured and 

 uninjured sets of seedlings exhibited similar fungal successions, 

 involving a procession from Hyphomycetes to Sphaeropsidales, 

 Ascomycetes, and Hyphomycetes. It seemed that the fungi might take 

 the place of mechanical injury as the agents which would cause uninjured 

 seedlings to be susceptible to bacterial -protozoan destruction of the 

 starch-laden pith tissues. In any case, a unique community of fungi 

 appeared to play an important part, in conjunction with bacteria, in 

 the first stages of conversion of seedling biomass to microbial 

 biomass, the first step in the passage of seedling energy into the 

 estuarine food web. (Author's summary and G.S.) 



Keywords: plant succession, fungi, red mangrove, detritus, estuarine 

 ecosystem, Florida 



III-C-8 



Fell, J.W., and I.M. Master. 1973. Fungi associated with the degradation 

 of mangrove ( Rhizophora mangle L.) leaves in South Florida. Pages 455-465 

 in^L.H. Stevenson and R.R. Colwell, eds., Estuarine microbial ecology. 

 University of South Carolina Press, Columbia. 



Odum and Heald observed that during the degradation of the mangrove 

 leaf there is a significant increase in the relative amount of protein 

 and conjectured that the fungal protein might be an important food 

 source for detrital consumers. As a continuation of these observations, 

 the authors initiated a program to ascertain the role of fungi in 

 this degradation system. In the initial phases of the study, they 

 examined the decaying leaves to determine which fungi were present 

 during the various stages of the process. The paper lists those fungi 

 that were identified, discusses observations on the sequences of 

 infestations, and generally characterizes the leaf fungal community. 



The authors conclude that it appears that a wide range of fungal 

 genera, including Phycomycetes , Deuteromycetes, and Ascomycetes, are 

 associated with the degradation of the mangrove leaves. Considerable 

 research is required to determine the specific role of these organisms 

 in the food web, although it has been postulated that they are important 

 in the production of protein as a food source for small fishes and 

 invertebrates. It is extremely important to understand the dynamics 

 of this ecosystem and the effects of alterations in environmental 

 conditions. The mangroves of south Florida are being subjected to 

 a variety of abnormal conditions, including effluents from domestic 

 and industrial sources; therefore, it is necessary to know how these 



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