The effects of culture medium formulations on the kinetics of infective juvenile (IJ) production of the entomopathogenic nematode Steinernema carpocapsae in submerged monoxenic culture, were studied at the cylindrical-bottle scale using six culture media containing agave juice from Agave spp. among other ingredients. The IJ production kinetics was well modelled through a re-parameterised 3-parameter Gompertz model with kinetic parameters: IJ-lag phase lambda (IJ) (day), maximum IJ-stage production rate m (max )(day(-1)), and IJ-multiplication factor (C (IJ)/C (IJ,0))(max)(-). The variation of lambda (IJ) was not very important within fermentations (10.3-16.2 days); nonetheless, important effects were observed on m (max) (32.8-241.2 days(-1)) and (C (IJ)/C (IJ,0))(max) (66(-) to 611.4(-)). Particularly, maximum values of m (max) and (C (IJ)/C (IJ,0))(max) were obtained in medium A4 (0.276 l l(-1) agave juice, 17 g l(-1) yeast extract, 12 g l(-1) dried egg yolk, 0.025 l l(-1) corn oil). Also, the maximum IJ concentration (249,444 per ml) was achieved in A4-fermentations.