Efficiency of Three Egg Parasitoid Species on Fall Armyworm (Lepidoptera: Noctuidae) in Laboratory and Field Cages

Egg parasitoids are the most used natural enemies in biological control of Spodoptera frugiperda (J.E. Smith), a pest of gramineous plants native to the Americas that recently invaded Africa and some countries of Asia. Although Trichogramma pretiosum (Riley) is one of the main species used against this pest, there are other species with equal or greater parasitism potential. The objective of this work was to compare, in laboratory and in field cages, the parasitism of Telenomus remus Nixon, Trichogramma atopoviritia (Oatman and Platner), and T. pretiosum on S. frugiperda eggs. Telenomus remus and T. atopoviritia reached the highest percentages of parasitism in laboratory (>70%) which did not differ statistically from each other. Trichogramma pretiosum had the lowest percentage of parasitism (29%) of the three. In the field cage assays. Te. remus parasitized 30% of the S. frugiperda egg masses. and T. pretiosum parasitized about 7.5% of the egg masses. These results underscore the importance of adequate selection of egg parasitoids for their use in biological control programs by augmentation against S. frugiperda.

Automated summary

Egg parasitoids such as Telenomus remus and Trichogramma atopoviritia showed high levels of parasitism on Spodoptera frugiperda eggs in laboratory settings, while Trichogramma pretiosum had the lowest rate. In field cage assays, Te. remus parasitized around 30% of the egg masses, highlighting the importance of selecting the right egg parasitoids for biological control programs against S. frugiperda.