Optimization of in vitro solid culture of Heterorhabditis bacteriophora Poinar, 1976 (Rhabditida: Heterorhabditidae) HBH hybrid strain

Entomopathogenic nematodes are soil-dwelling biocontrol agents. EPNs need an insect host to complete their life cycle, and they kill during its development. The major disadvantage of is the high cost commercial products. Thus, there many studies focused on reducing production costs by optimization mass production. In a previous project, Heterorhabditis bacteriophora Poinar, 1976 (Rhabditida: Heterorhabditidae) HBH hybrid strain was developed from local isolates. This patented due superior bioecological characteristics. study aimed optimize in vitro solid strain. All laboratory trials were performed between 2017 2018, Nematology Laboratory Bursa Uludağ University, Faculty Agriculture, Department Plant Protection. For optimization, additional supplementary ingredients (soy lecithin egg yolk), temperature (24, 28 32°C) medium pH (5, 7 9) selected as parameters. Optimization evaluated based hermaphrodite numbers, total infective juveniles (IJs), IJ body length virulence. Based results, best combination found agar containing soy lecithin, 28°C 7. Also, media with 9 markedly reduced yield. Consequently, optimum values for some important parameters determined.