A contribution to the study of the intestinal microflora of Indian earthworms

Abstract

1. The literature on the microorganisms in the intestine of earthworms is reviewed in the introduction. 2. Our methods for the isolation of various types of microorganisms are described. 3. The microbiological examination of 60 Indian earthworms mostly by enrichment culture methods resulted in the demonstration of a mixed microflora as represented by our 343 isolates. Their physiological activities, such as oxalate decomposition, cellulose decomposition, nitrogen fixation and asparagine utilisation, are described and their implication in soil fertility pointed out. Some frequently occurring types like Pseudomonas, coryneform Bacteria, Nocardias, Streptomycetes and sporeforming Bacilli compose the normal flora. 4. Nitrosifying and nitrifying bacteria do not appear to be associated with the earthworm intestine. No coliform bacteria of significance from the public health point of view seem to be associated with the earthworm. 5. The isolation of the cellulolytic, but at the same time plant pathogenic, Fusaria presents a problem in judging the practical value of the earthworms. 6. The results suggest the earthworms to be important agents contributing to soil fertility.