Trans-generational effects on diapause and life-history-traits of an aphid parasitoid

K Tougeron; M Devogel; J van Baaren; C Le Lann; T Hance

doi:10.1016/j.jinsphys.2019.104001

Trans-generational effects on diapause and life-history-traits of an aphid parasitoid

J Insect Physiol. 2020 Feb-Mar:121:104001. doi: 10.1016/j.jinsphys.2019.104001. Epub 2019 Dec 24.

Authors

K Tougeron¹, M Devogel², J van Baaren³, C Le Lann³, T Hance⁴

Affiliations

¹ Institut de recherche en biologie végétale, Département de sciences biologiques, Université de Montréal, 4101, Sherbrooke Est, Montréal, Québec H1X 2B2, Canada; Univ Rennes, CNRS, ECOBIO (écosystèmes, biodiversité, évolution) - UMR 6553, 263 Avenue du Général Leclerc, 35000 Rennes, France; Earth and Life Institute, Centre de recherche sur la biodiversité, Université Catholique de Louvain, 1348 Louvain-la-Neuve, Belgium. Electronic address: tougeron.kevin@gmail.com.
² Univ Rennes, CNRS, ECOBIO (écosystèmes, biodiversité, évolution) - UMR 6553, 263 Avenue du Général Leclerc, 35000 Rennes, France; Earth and Life Institute, Centre de recherche sur la biodiversité, Université Catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.
³ Univ Rennes, CNRS, ECOBIO (écosystèmes, biodiversité, évolution) - UMR 6553, 263 Avenue du Général Leclerc, 35000 Rennes, France.
⁴ Earth and Life Institute, Centre de recherche sur la biodiversité, Université Catholique de Louvain, 1348 Louvain-la-Neuve, Belgium.

PMID: 31874137
DOI: 10.1016/j.jinsphys.2019.104001

Abstract

Transgenerational effects act on a wide range of insects' life-history traits and can be involved in the control of developmental plasticity, such as diapause expression. Decrease in or total loss of winter diapause expression recently observed in some species could arise from inhibiting maternal effects. In this study, we explored transgenerational effects on diapause expression and traits in one commercial and one Canadian field strain of the aphid parasitoid Aphidius ervi. These strains were reared under short photoperiod (8:16 h LD) and low temperature (14 °C) conditions over two generations. Diapause levels, developmental times, physiological and morphological traits were measured. Diapause levels increased after one generation in the Canadian field but not in the commercial strain. For both strains, the second generation took longer to develop than the first one. Tibia length and wing surface decreased over generations while fat content increased. A crossed-generations experiment focusing on the industrial parasitoid strain showed that offspring from mothers reared at 14 °C took longer to develop, were heavier, taller with wider wings and with more fat reserves than those from mothers reared at 20 °C (8:16 h LD). No effect of the mother rearing conditions was shown on diapause expression. Additionally to direct plasticity of the offspring, results suggest transgenerational plasticity effects on diapause expression, development time, and on the values of life-history traits. We demonstrated that populations showing low diapause levels may recover higher levels through transgenerational plasticity in response to diapause-induction cues, provided that environmental conditions are reaching the induction-thresholds specific to each population. Transgenerational plasticity is thus important to consider when evaluating how insects adapt to changing environments.

Keywords: Aphidius ervi; Bet-hedging; Climate-change; Phenotypic plasticity; Temperature; Transgenerational plasticity.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adaptation, Physiological
Animals
Aphids / parasitology
Body Size / physiology
Climate Change
Cohort Effect*
Diapause, Insect / physiology*
Environment
Fat Body / physiology
Hymenoptera / physiology*
Life History Traits
Temperature