Ovipositional choice tests among Heliothis virescens (F.), Helicoverpa zea (Boddie), and the H. virescens-H. flexa backcross were conducted in the-laboratory for Microplitis croceipes (Cresson). The mean number of hosts parasitized was 7.2, 6.3, and 6.5/petri dish for H. virescens, H. zea, and the backcross, respectively. There were no significant differences among these means. In field tests, the mean number of H. viresecens larvae parasitized (0.373/M2) was not significantly different from the mean number of H. viresecens - H. subflexa larvae parasitized (0.392/m²). The mean number of H. zea larvae parasitized (0.233/m²) was significantly lower than those of the other two species.