Insect Viruses

Abstract

Viruses from over 16 families have been isolated from insects to date and show as much variation in structural and organisational paradigms as viruses from most other animal classes. Unique to the insect viruses is the ability of several families to produce a large pseudocrystalline occlusion body that protects the mature virus particles in the environment. Such occlusion bodies have led to these viruses evolving a complex array of associations with their insect host and in many cases causing large‐scale disease epizootics. Some of these viruses have been used for the purposes of biocontrol of insect pests in agriculture. Among the remaining nonoccluded insect viruses all of the basic structural and organisational paradigms are present in different families. Many insect viruses seem able to coexist in a single host without causing obvious disease. However, the life history strategies of their insect hosts has led the insect viruses to evolve some intriguing replicative strategies of their own that have few, if any, counterparts among the other animal viruses. Key Concepts: Insect viruses have genomes that may comprise double‐ or single‐stranded DNA or RNA. Insect viruses exhibit as much structural diversity as viruses that infect any other form of life. Insect viruses may be enveloped or non‐enveloped. Some insect viruses may form occlusion bodies comprising virions embedded within a protein matrix. Insect viruses may have evolved 350–400 million years ago. Many insect viruses share genetic and structural similarities with viruses of vertebrates. Some insect viruses are unique to invertebrate species. Insect viruses can be highly pathogenic to their hosts or cause little or no signs of infection. Some insect viruses have been used as biopesticides to control insect pests.

Genome organization and molecular characterization of the threeFormica exsectaviruses—FeV1, FeV2 and FeV4

“…obs., 2013), but the underlying cause has not been investigated. To date, no close relatives to FeV4 have been reported from social insects, and in Mononegavirales disease symptoms are mostly unknown, with the exception of the Sigma virus that causes vulnerability to CO 2 exposure in Drosophila melanogaster (Possee & King, 2014) . We also found cases of co-infection by two FeV strains in F. exsecta , cases of which have also been reported in S. invicta, and honey bees, where it carries an elevated risk of colony demise (Chen et al, 2004; Allen, Valles & Strong, 2011; Tantillo et al, 2015).…”

“…Insect-infecting viruses are known from 16 different virus families, and these show extensive variation in genome, and surface protein structure (Possee & King, 2014). However, to date viruses that infect ants are only known from the Dicistroviridae and Iflaviridae families, which belong to the order Picornavirales (positive sense single strand RNA viruses).…”

The Role of Chrysoperla carnea (Steph.) (Neuroptera: Chrysopidae) as a Potential Dispersive Agent of Noctuid Baculoviruses

“…In contrast to chemical pesticides, BV act as ecological entities that have the potential to infect, multiply, spread (both horizontally and vertically), and persist on plants and soil [4]. Amongst the dissemination strategies of BV, the horizontal transmission by the release of occlusion bodies (OBs) from infected corpses represents the main spreading path [1,5].…”

“…IL = Infected Larvae 1. Larvae consumed daily (total number of larvae daily offered = 10), F 2,141 = 1.13, p= 0.327; 2 Duration of the third larval stage, F 2,141 = 18.30, p < 0.001;3 Number and percentage of formed pupae, X 2 2 = 3.50, p = 0.174;4 Duration of the pupal stage, F 2,131 = 61.91, p < 0.001; 5 F 2,131 = 7.49; p < 0.001.…”

Diverse RNA Viruses Discovered in Three Parasitoid Wasps of the Rice Weevil Sitophilus oryzae

“…stranded RNA viruses (1)(2)(3). Species abundance and diversity of RNA viruses also exist in insects, the largest group in invertebrates (4)(5)(6). Nowadays, the application of metagenomics accelerates the studies of viral identification, persistence, spread, and interaction with both their insect hosts and other microbes.…”