• Effect of Temperature on the Virulence of Entomopathogenic Nematodes

    Manana Lortkipanidze1, Kazim Hwseynov2, Mzia Kokhia1, Oleg Gorgadze1, Madona Kuchava1

    1. Department of entomopathogens, Ilia State University, Institute of Zoology, 3/5 Kakuca Cholokashvili Ave, Tbilisi 0162, Georgia.
    2. Scientific-Research Institute of Plant Protection and Technical Cultures, 91 St. Aziz Aliyev, Ganja, AZ2002, Azerbaijan.

    Abstract:

    Nowadays, the use of entomopathogenic nematodes as a biological control agent is a key component in IPM system. Entomopathogenic nematodes of the genera Steinernema and Heterorhabditis (Nematoda: Rhabditida) are extraordinarily lethal to many important insect pests, yet are safe for plants and animals. They are the only insect-parasitic nematodes possessing an optimal balance of biological control attributes.

    The effect of temperature on the virulence of three species of entomopathogenic nematodes,  Steinernema thesami, Heterorhabditis bacteriophora and Steinernema feltiae was investigated. Last instar of Tenebrio molitor larvae were choosing for experiment. In the laboratory, all three nematode species successfully reproduced inside T. molitor larvae. H. bacteriophora produced the highest number of infective juveniles per larva at 30°C than S. feltiae and S. thesami. S. feltiae caused the highest mortality of larvae at 20°C, whereas S. thesami infected T. molitor larvae at the widest temperature range and killed insects between 8-35°C. Based on the present study, we indicate that entomopathogenic nematodes have well-defined thermal breadths for their development and reproduction.

    Keywords: Entomopathogenic nematodes, Heterorhabditis, Steinernema, Tenebrio molitor, biocontrol.

    Pages: 32 – 38 | Full PDF Paper