The tomato leaf miner is recently emerged threat of solanaceae plants. It was addressed to compare the efficacy of two species of entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora at three different soil textures (loamy― sand, sandy― loam and coco— peat), three ranges of temperature (19, 25 and 31 ºC), and three different exposure times (65, 240 and 480 min). Results showed that H. bacteriophora with LC50 1 IJs/cm2 was more effective compared to S. carpocapsae with LC50 2 IJs/cm2. The last instar larva was more susceptible compared to pupa and adult stages. The emergence of IJs from adult demonstrated the reproduction of S. carpocapsae within adult. Both nematode species induced a high mortality rate in the loamy― sand (88.9%) compared to sandy― loam soil (16.8%). The maximum mortalities of 95% for H. bacteriophora and 90.6% for S. carpocapsae were observed at 31±1 ˚C. However, at 25± 1 ˚C, the mortality rate was obtained 96% and 89.2% for H. bacteriophora and S. carpocapsae, respectively. The exposure of the last instar larvae for 240 min to the S. carpocapsae was appropriate to induce an infection level about 95.5±3.2% on the larvae, whereas 76.9±4.4% of the larvae were infected after 65 min of exposure. The EPN species were able to find and to kill larvae within the galleries. These results suggest that S. carpocapsae might have the potential to control T. absoluta in greenhouse under 31±1 ˚C with 65 min exposure, although this assertion requires greenhouse testing.

Keywords