The objective of this research was to evaluate the biology and the thermal requeriments of five strains of Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) collected in commercial areas of tomato, in Espírito Santo State, on eggs the tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) under constant and alternating temperatures. The duration of the development cycle (egg-adult) of the five strains of T. pretiosum reared in eggs of T. absoluta was affected significantly by the temperature, in the band of the constants (15 to 30°C). This same fact was not observed in the alternated temperatures (26/14 and 29/16°C). The performance of the strains in the different temperatures, showed that L2 and L5 presented the best results concerning the emergency rate of their descendants of viability. The sex ratio of the five strains was affected by the temperature, with significant differences obtained in all the bands of the temperatures (constant and alternating) studied. The strains of T. pretiosum showed a base temperature (tb) variyng from 8.70 to 13.45°C, and a thermal constant (K) from 90.09 to 159.43 day degrees.
Insecta; Trichogrammatidae; biological control; tomato leafminer
