Applications of Molecular Diagnostics for Quality Control in Rearing of Spodoptera frugiperda (Lepidoptera: Noctuidae) Larvae for Experimental Use

Abstract

Illumina MiSeq sequencing of 16S rRNA genes was applied in a molecular diagnostic analysis of healthy and dead larvae obtained from a Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) colony. The results indicated the presence of Enterococcus (Lactobacillales: Enterococcaceae) with an average abundance of 89.2% and 94.8% in healthy and dead larvae, respectively. Pseudomonas (Pseudomonadales: Pseudomonadaceae) and Acetobacter (Rhodospirillales: Acetobacteraceae) were present in lower abundance. Additional metagenomic results revealed the presence in dead larvae of viral sequences related to Alphabaculovirus in high relative abundance compared with healthy larvae. Additionally, viral sequences of tomato leaf curl Laos virus, Heliothis zea (Boddie) (Lepidoptera: Noctuidae) nudivirus, Clostera anachoreta (Denis & Schiffermüller) (Lepidoptera: Notodontidae) granulovirus, and Tipula oleracea L. (Diptera: Tipulidae) nudivirus were detected. Our results show that molecular detection of pathogenic agents is a useful tool during insect rearing as a quality control to avoid the spread or acquisition of potential pathogens.