Bio-Efficacy of Fusarium humuli and Fusarium incarnatum (Hypocreales: Nectriaceae) Against Larvae of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) Under Controlled Conditions

Abstract

Spodoptera frugiperda has impaired the productivity of staple crops in Tanzania since it was first reported in 2017. The overutilization of synthetic insecticides as an immediate remedy has led to new ecological problems along effects on public health. Using entomopathogenic fungi (EPF) is perceived as a safer way, and therefore, Fusarium incarnatum (Vw3) and Fusarium humuli (Vw5) from the SUA germplasm collection were tested against S. frugiperda larvae at levelled concentrations; C1, C2 and C3 alongside 0.1% Triton X-100 and Banophos 720 EC (20 ml/20 L) as negative (C-) and positive (C+) controls, respectively. The findings showed C+ inflicted the highest death rates (84% and 97% for Vw3 and Vw5, respectively), followed by C1 (48.8% and 55.5% for Vw3 and Vw5, respectively) and C2 (22.2%, 28.8% for Vw3 and Vw5, respectively). Moreover, C3 inflicted mortalities by 11.1% and 12.2% for Vw3 and Vw5 respectively, while C- inflicted mortalities by 7.7% and 1.1% for Vw3 and Vw5, respectively. Significant differences were observed in concentrations and ages of the insects. However, more studies are recommended to validate their safety and compatibility with other IPM components prior to qualifying the EPF for the control of S. frugiperda.