Eco-friendly management of fall armyworm: can host-plant intercropping drive to a sustainable IPM?

Although over 350 species of plants have been documented to host the fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), its invasion in West Africa has been mainly on maize. This study investigated the factors that limit the host utilization and tested the effects of intercropping of Poaceae (maize, sorghum, rice and Proso millet), Solanaceae (tomato and sweet pepper), and Fabaceae (cowpea and soybean) plants on FAW severity. The laboratory larvae fed with those crops showed higher pupation rates for maize (33.6%) than sorghum (20%), rice (24.2%), Proso millet (17.6%), tomato (fruit = 5.3% and leaf = 6 .4%), sweet pepper (fruit = 1.3% and leaf = 1.6%). Only larvae fed with Poaceae plants reached the adult stage. Female ovipositional potentiality was higher with maize compared to other Poaceae plants. In the field experiments, FAW severities were recorded only on Poaceae plants. However, the severity of FAW was significantly reduced on the intercropped maize with other crops compared to monocultures of maize. Therefore, intercropping can be considered as an eco-friendly FAW-IPM program in West Africa.