Physiological reactions of some entomopathogenic nematodes to long-term storage

Entomopathogenic nematodes (EPNs) are commonly used for pest control. Determining the optimal storage duration for EPNs is crucial for their effective utilization. The aim of this study is to determine the efficacy and reproductive capacities of some EPNs stored for different durations. Heterorhabditis bacteriophora Poinar, 1976 (Rhabditida: Heterorhabditidae) HBH Hybrid Strain, HBNL, and HB4 isolates, as well as Steinernema feltiae Weiser, 1955 (Rhabditida: Steinernematidae) SADIÇ and ST5 isolates, were used in the study. The Infective Juveniles (IJs) stored at 4°C for 6, 12, 18, and 24 months were assessed for their efficacy and reproductive capacities on last instar larvae of Galleria mellonella L., 1758 (Lepidoptera: Pyralidae) at the end of the periods. This study was conducted at Bursa Uludaǧ University, Plant Protection Department, Nematology Laboratory. The highest mortality rate observed on G. mellonella larvae was 86.67% on the H. bacteriophora HBH Hybrid Strain stored for 6 months. Similarly, the highest reproductive capacity was determined to be 153 000 IJs/G. mellonella larva, also on the H. bacteriophora HBH Hybrid Strain stored for 6 months. This study showed significant results in determining the effects of storage durations on the efficacy and reproductive capacity of the EPNs.