ABSTRACT:
The objective of this study was to evaluate extent of larval period, larval survival (%), food consumption, and pupal biomass ofSpodoptera eridania and Spodoptera frugiperda (Lepidoptera:Noctuidae ) fed on fresh ears of field corn expressing Bt proteins (Cry1F and Cry1F+Cry1A.105+Cry2Ab2). Larvae ofSpodoptera spp. survived less than two days when they consumed Bt corncobs and showed 100% mortality.Spodoptera eridania reared on non-Bt corn cobs showed higher larval development (21.6 days) thanS. frugiperda (18.4 days) and lower viability (56.4% and 80.2% forS. eridania and S. frugiperda , respectively). A higher amount of corn grains was consumed byS. eridania (5.4g) than byS. frugiperda (3.9g). In summary, this study demonstrated that the toxins Cry1F and Cry1F + Cry1A.105 + Cry2Ab2 expressed in fresh corn cobs contributed to protect ears of corn against S. frugiperda and the non-target pestS. eridania . However, itis important to monitor non-Bt cornfields because of the potential of both species to cause damage to ear sof corn.
Key words:
biology; integrated pest management; fall armyworm; Southern armyworm; varietal resistance
