Evaluating the effectiveness of isolated fungi against Fall armyworm (Spodoptera frugiperda)

Abstract

Spodoptera frugiperda, also known as the fall armyworm (FAW), is a polyphagous, destructive, and internationally dispersed insect pest that poses a serious danger to the production of cereals in Africa. Entomopathogens are a safe and environmentally beneficial way to control insect infestations when the all types of insecticides being used to control FAW are linked to a range of serious human health problems from respiratory to cancer. The objective of this study was to identify fungi from local soil that were effective against S. frugiperda larvae. Aluminum foil was used to gather soil samples from various maize growing regions in Ethiopia. Fungi isolated from soil samples and suspended conidia preparation was done in the mycology lab of Addis Ababa University in Ethiopia. At Melkasa Agricultural Research Center a bioassay test was conducted on S. frugiperda larvae. Three replications and a fully randomized design was used to set up the six treatments for the experiment. Twenty FAW larvae (3rd instar) were put into sterile Petri dishes with a diameter of 9 cm and a filter paper lining. A new, unopened syringe was used to inject 3 ml of the suspended solution into each treatment. As a negative control, distilled and sterilized water was used. FAW larval mortality was measured and examined independently for each treatment using GLM, followed by a Tukey's HSD post-hoc test. The cumulative mortality rate (P = 0.0001) and second-day mortality rate (P = 0.001) showed a significant difference between regimens. These noteworthy variations were seen in third instar larvae. S. frugiperda larvae from isolation fungi F1 and F5 had the highest (96.67%) and lowest (80.0%) mean cumulative death rates. Under negative control, the mean cumulative mortality rate was 8.33%. The outcomes showed that S. frugiperda could potentially be controlled by fungal isolates found in maize fields. Conidial concentration, as well as field evaluation, characterisation, and species identification of isolate fungi, all require more study.