Potential for Biological Controls of 'Cladophora glomerata'

摘要

The purpose of this research program was to determine whether or not there were natural biological controls of Cladophora glomerata that could be developed. Two avenues of research were pursued. One was to study macroscopic organisms that were known to occur in the Great Lakes area to see if any of them would prefer C. glomerata as a food source and under what conditions the desirability of C. glomerata could be increased. The second approach was to study microorganisms, particularly fungi, which were of common occurrence in aquatic ecosystems to determine if they might function as controls for C. glomerata. The results of these studies show that C. glomerata was a poor food for Physa heterostropha, Orconectes propinquus, Rana pipiens, Ictalurus punctatus, and Pimephales promelas. Not only would these species not eat the food, but if they did eat the food there seemed to be a deleterious effect. In the studies with snails it was evident that egg production was greatly curtailed on the C. glomerata diet. The second avenue of approach was to study the effect of fungi as parasites on C. glomerata. One fungus, Acremonlum killense (Fungi Imperfecti) was found to have an antagonistic effect on C. glomerata.