Three strains of Steinernema carpocapsae (strains 25, DD-136, and All) were used to investigate the possibility of parthenogenesis in this species of entomopathoganic nematode. A plaster plate with a depression (dia. of 1 cm) in the center was designed for this experiment. Heat-treated last instar Galleria larvae or an equivalent weight of autoclaved poultry egg yolk were used in separate experiment to fill up the hole. A single S. carpocapsae infective juvenile was inoculated onto each sample of medium. Each plaster plate was assigned as 1 replicate and each treatment consisted of 20 replicates. For both media plates without nematode inoculation were assigned as the control. Oevelopment was observed daily and the number of progeny produced per nematode was counted 7 days after inoculation. For the yolk medium, the ratios of replicates producing progeny were 45% for strains 25 and DD-136, and 55% for strain All. The number of progeny produced by strain 25 was below 100. The number of progeny produced by DD-136 ranged from 103 to 104 with a high proportion at 103. For strain All, the number of progeny produced ranged from 102 to 104 with a high proportion at 103. For the Galleria larva medium, the ratios of replicates producing progeny were 50% for strains 25 and All, and 55% for strain DD-136. The number of progeny produced by strain 25 was below 100. The number of progeny produced by DD-136 ranged from 103 to 104 with a high proportion at 103. For strain All, the number of progeny produced ranged from 102 to 104 with a high proportion at 103.
Parthenogenesis, Steinernema carpocapsae, Progeny, Poultry egg yolk, Galleria
