The effect of the number of bacteria Photorhabdus luminescens(Thomas and Poinar, 1979) on the population dynamics of nematodesHeterorhabditis megidis (Poinar, Jackson and Klein, 1987) in in vitro culture

Abstract: The study aimed at estimating the correlation between the nematode Heterorhabditismegidis (strain KV–136) development and the number of bacterial colonies of Photorhabdusluminescens. Analyses concentrated on the dynamics of the population growth of H. megidis inliquid cultures at different aeration (160rpm, 200rpm), at constant biotic and abiotic parameters(initial dose of nematodes introduced to the culture 2,340 dauer larvae (DL)/ml, temperature25°C, the number of bacterial colonies 0.3 x 107). Performed experiments showed that aeration at200 rpm favourably affected the number of colonies of P. luminescens (24.14 x 107). Highdensity of bacteria at this aeration variant resulted in an earlier (on the fifth day of the culture)maximum increase in the number of nematode individuals (1,239.6 H/ml) than in the cultureaerated at 160rpm.