CpGV-M Replication in Type I Resistant Insects: Helper Virus and Order of Ingestion Are Important

Abstract

The genetic diversity of baculoviruses provides a sustainable agronomic solution when resistance to biopesticides seems to be on the rise. This genetic diversity promotes insect infection by several genotypes (i.e., multiple infections) that are more likely to kill the host. However, the mechanism and regulation of these virus interactions are still poorly understood. In this article, we focused on baculoviruses infecting the codling moth, Cydia pomonella: two Cydia pomonella granulovirus genotypes, CpGV-M and CpGV-R5, and Cryptophlebia peltastica nucleopolyhedrovirus (CrpeNPV). The influence of the order of ingestion of the virus genotypes, the existence of an ingestion delay between the genotypes and the specificity of each genotype involved in the success of multiple infection were studied in the case of Cydia pomonella resistance. To obtain a multiple infection in resistant insects, the order of ingestion is a key factor, but the delay for ingestion of the second virus is not. CrpeNPV cannot substitute CpGV-R5 to allow replication of CpGV-M.

Effects of Mixed Baculovirus Infections in Biological Control: A Comprehensive Historical and Technical Analysis

“…Regarding GV + GV mixtures, no study has been published describing natural co-infection produced by different GVs. However, several studies have described natural or experimental co-infections with mixtures of GV genotypic variants [ 84 , 85 , 86 ] or laboratory assays using closely related GVs on permissive hosts [ 87 ].…”

Nucleopolyhedrovirus Coocclusion Technology: A New Concept in the Development of Biological Insecticides

“…Nonetheless, other possible interactions could occur between viruses infecting the same host, but different cells, in a trans interaction mode. For NPVs, the success of primary infections appears to rely on the former, but granuloviruses probably use the latter, possibly mediated through cells infected by helper genotypes, which release a diffusible factor that circulates within the infected larva ( Hinsberger et al, 2021 ). Future studies will doubtless provide additional evidence of the importance of intra- and interspecific social interactions among viruses ( Sanjuán, 2021 ), and aid the growing recognition of the value of sociovirological approaches to understanding these pathogens.…”