The Impact of a Cypovirus on Parental and Filial Generations of Lymantria dispar L.
by
, , and
Yuriy B. Akhanaev
1,*
,
Sergey V. Pavlushin
1,
Daria D. Kharlamova
1,2,
Daria Odnoprienko
3,
Anna O. Subbotina
1,3,
Irina A. Belousova
1,
Anastasia N. Ignatieva
4,
Anastasia G. Kononchuk
4,
Yuri S. Tokarev
4
and
Vyacheslav V. Martemyanov
1,*
1
Institute of Systematics and Ecology of Animals, SB RAS, Frunze Str. 11, Novosibirsk 630091, Russia
2
Institute of Biology, Irkutsk State University, Karl Marx Str. 1, Irkutsk 664003, Russia
3
Department of Molecular Biology and Biotechnology, Novosibirsk State University, Pirogova Str. 1, Novosibirsk 630090, Russia
4
All-Russian Institute of Plant Protection, Sch. Podbelskogo 3, Pushkin, St. Petersburg 196608, Russia
*
Authors to whom correspondence should be addressed.
Insects 2023, 14(12), 917; https://doi.org/10.3390/insects14120917
Submission received: 2 October 2023
/
Revised: 29 November 2023
/
Accepted: 29 November 2023
/
Published: 30 November 2023
(This article belongs to the Section Insect Behavior and Pathology)
Simple Summary
The spongy moth Lymantria dispar L., formerly known as the gypsy moth, is an important forest pest in the Holarctic region. To control this pest, the use of microbial pathogens is important because they are usually possess more selective and environmentally safe than chemical insecticides. In this study, we estimated the virulence of a new strain of cypovirus-1 isolated from the Siberian moth Dendrolimus sibiricus (DsCPV-1) against L. dispar larvae and its impact on a subsequent L. dispar generation. We observed increased insect mortality and longer larval development times following DsCPV-1 infection. DsCPV-1 did not affect the fecundity of surviving females, but considerably reduced the hatching ability of eggs of these females. Offspring of surviving parents that had been challenged with DsCPV-1 were tested to see if the virus affected their susceptibility to a stress factor (starvation). In addition, we checked the ability of cypovirus-1 to be transmitted vertically via an alternative host (spongy moth). Estimation of this feature may be useful for microbial control. Although the DsCPV-1 infection of parents had adverse effects on the spongy moth larvae, DsCPV-1 was not detectable in their offspring.
Abstract
Recently, we found that the spongy moth Lymantria dispar L. is susceptible to infection by a Dendrolimus sibiricus cytoplasmic polyhedrosis virus (DsCPV-1). In the present study, we evaluated the pathogenicity of DsCPV-1 against L. dispar larvae and its impact on surviving insects after the infection. Offspring of virally challenged insects were tested for susceptibility to a stress factor (starvation). In addition, we used light microscopy and quantitative polymerase chain reaction (qPCR) to test the ability of DsCPV-1 to be transmitted vertically. We found insect mortality of the L. dispar parents following the infection was positively associated with DsCPV-1 dose. DsCPV-1 was lethal to second-instar L. dispar larvae with a 50% lethal dose (LD50) of 1687 occlusion bodies per larva. No vertical transmission of DsCPV-1 to offspring larvae was detected, while the majority of insect deaths among offspring larvae were caused by microsporidia (Vairimorpha lymantriae), which was harbored by the parents. The offspring of virally challenged parents exhibited a higher number of detected microsporidia compared to the control. Our findings suggest that the application of DsCPV-1 is effective in controlling pests in terms of transgenerational impact following virus exposure.
Keywords:
spongy moth; Lymantria dispar; cypovirus; microsporidia; virulence
