Evaluating the implications of moisture deprivation on certain biochemical parameters of the earthworm Eudrilus eugeniae with microbial population and exoenzyme activities of the organic substrate

Abstract

Reduction in moisture in the top soil and decomposing organic substrate is likely to influence the epigeic earthworms along with the microbial population and exoenzyme secretions. This study reports the results of the effects of consistent moisture reduction in semidecomposed organic substrate on the tissue protein, lipid peroxidation and catalase activity of the earthworm Eudrilus eugeniae along with pH, organic carbon reduction, bacterial-fungal population, activities of exoenzymes, amylase, cellulase, invertase over an experimental period of 22 days. Consistent depletion in tissue protein, increase in lipid peroxidation level and catalase activity was observed in the earthworm with moisture depletion. Catalase activity indicated significant negative correlation with substrate moisture. Significant differences in the carbon reduction, microbial population, exoenzyme activities in the substrate was observed with reduction of moisture and with respect to control. Significant positive correlation was observed between percent substrate moisture with microbial population and activities cellulase. It was concluded that desiccation of decomposing organics could enhance physiological stress on the earthworm and adversely impact the microbial population, exoenzyme secretions, consequently impairing mineralization.