The Effects of Various Organic and Inorganic Fertilizers on the Density of Entomopathogenic Nematodes Symbiont

Entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora and their bacterial symbionts Xenorhabdus nematophila and Photorhabdus luminescens (P. luminescens), represent a specific agricultural niche. The successful integration of entomopathogenic nematodes (EPN) as regular use biological control agents require specific knowledge and understanding of the adaptation and establishment of applied biological control agents in agricultural ecosystems. For many years, the pest management capabilities of these pathogenic partnerships have been implemented in biological control settings. In this study, ten fertilizers were examined to explore the effects of nitrogen, phosphorus, and potassium (NPK) on the production of entomopathogenic bacteria Xenorhabdus nematophila and Photorhabdus luminescens. Laboratory exposure to fertilizer concentrations (0.5-2.5%) was used to determine the production of each bacterial species. Results conclude that P. luminescens are generally more sensitive to fertilizer than X. nematophila. Moreover, fertilizers containing high nitrogen suppressed bacterial densities more readily than those with lesser amounts. This paper summarizes the effects of the three important nutrients found in various concentrations of organic and inorganic fertilizers on entomopathogenic bacteria production.