Investigation on comparison of persistence and storage of the entomopathogenic nematode Heterorhabditis bacteriophora HBHhybrid strain after In vivo and In vitro productions

Entomopathogenic nematodes (EPN) are living things that play an active role in biological control. EPNs are known as one of the most effective solutions against underground pests due to the difficulty of applying synthetic pesticides and the serious threat to the environment. EPNs are stored according to certain storage conditions before being applied. It is expected to maintain its effectiveness in the area where it is applied for a maximum period of time after application. This thesis study is carried out to determine the persistence and storage time of EPNs in the soil under predetermined climatic conditions. Heterorhabditis bacteriophora HBH hybrid strain infective juveniles (IJ) are produced in two different methods in vivo and in vitro. To assess the persistence of Heterorhabditis bacteriophora HBH hybrid strain, is produced in vivo and in vitro, are filled into 6 cm petri dishes, infective juveniles (IJ) are left inside and dishes and Galleria mellonella (end stage) larvae are deposited into the soil at ten-day intervals. After two days, G. mellonella larvae in the petri dish are removed and dissected. It is determined that in vivo production method (77.2 IJ / larva) is more effective than in vitro production (22.6 IJ / larva) in terms of the number of IJ individuals developed in G. mellonella. The IJs obtained by the in vivo method are able to maintain their effectiveness in the soil for 140 days in terms of infecting G. mellonella larvae, and the maximum infecting ability of IJs is determined on the 50th day. The IJs obtained by the in vitro method, on the other hand, are able to maintain their effectiveness in the soil for 170 days in terms of infecting G. mellonella larvae and the best time to infect is determined as the 40th day. In this thesis, the storage conditions of H. bacteriophora HBH hybrid strain IJs, which are produced in vivo and in vitro, are tested and kept in an incubator at 8, 12, 16, 20 and 24 °C for 3, 6, 9 and 12 days, respectively. The study showed that the lowest mortality rate (0.0548%) is produced in vivo and kept in an incubator at 8 °C for 3 days, the highest mortality rate (11.238%) is obtained with in vitro production and kept in an incubator at 24 °C for 12 days. H. bacteriophora HBH is found in hybrid strain IJs.