Guillaume Lacour1, Florian Vernichon2, Nicolas Cadilhac3, Sébastien Boyer4, Christophe Lagneau5, Thierry Hance6. 1. EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France; Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium. Electronic address: glacour@eid-med.org. 2. EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France. Electronic address: florian.vernichon@gmail.com. 3. EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France. Electronic address: cadilhac.nicolas@hotmail.fr. 4. UMR-MIVEGEC, Institut de Recherche pour le Développement, 34394 Montpellier, France. Electronic address: sebastien.boyer@ird.fr. 5. EID Méditerranée, 165 Avenue Paul-Rimbaud, 34184 Montpellier, France. Electronic address: clagneau@eid-med.org. 6. Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium. Electronic address: thierry.hance@uclouvain.be.
Abstract
BACKGROUND: The diapause of Aedes albopictus is maternally induced by photoperiod and initiates at the pharate larvae stage in eggs. This pre-diapause results in enhanced survival eggs during the winter. This study aims to disentangle the effects of photoperiod and diapause on embryonic developmental time and egg size in A. albopictus. A temperate strain capable to perform diapause and a tropical strain unable of diapause were reared at 21°C with long-(LD) and short-day (SD) lengths. Four distinct traits were studied on embryos and eggs were measured at the end of embryogenesis. RESULTS: The chronologies of embryo development for both strains were influenced by maternal photoperiod, especially in the temperate strain in which the development of SD eggs took longer than LD eggs. The delay increased gradually in the temperate strain, and reached up to 38 h at the end of embryogenesis. The kinetics of embryogenesis differed among the temperate and the tropical strains, each one of the 4 studied traits showing differences. For example the serosal cuticle was secreted precociously in the tropical strain. Egg width and volume are influenced by the maternal photoperiod and the strain×photoperiod interaction. For both strains, larger eggs were laid by female reared under SD when compared to LD. CONCLUSIONS: The influence of several maternal effects was demonstrated in this study. The diapause process modifies greatly the length of embryogenesis in the temperate strain, whereas the maternal photoperiod has a direct influence on egg size and embryogenesis regardless of the strain considered. These findings provide useful data on chronology of embryonic development for integrative biology studies of egg pre-diapause stages.
BACKGROUND: The diapause of Aedes albopictus is maternally induced by photoperiod and initiates at the pharate larvae stage in eggs. This pre-diapause results in enhanced survival eggs during the winter. This study aims to disentangle the effects of photoperiod and diapause on embryonic developmental time and egg size in A. albopictus. A temperate strain capable to perform diapause and a tropical strain unable of diapause were reared at 21°C with long-(LD) and short-day (SD) lengths. Four distinct traits were studied on embryos and eggs were measured at the end of embryogenesis. RESULTS: The chronologies of embryo development for both strains were influenced by maternal photoperiod, especially in the temperate strain in which the development of SD eggs took longer than LD eggs. The delay increased gradually in the temperate strain, and reached up to 38 h at the end of embryogenesis. The kinetics of embryogenesis differed among the temperate and the tropical strains, each one of the 4 studied traits showing differences. For example the serosal cuticle was secreted precociously in the tropical strain. Egg width and volume are influenced by the maternal photoperiod and the strain×photoperiod interaction. For both strains, larger eggs were laid by female reared under SD when compared to LD. CONCLUSIONS: The influence of several maternal effects was demonstrated in this study. The diapause process modifies greatly the length of embryogenesis in the temperate strain, whereas the maternal photoperiod has a direct influence on egg size and embryogenesis regardless of the strain considered. These findings provide useful data on chronology of embryonic development for integrative biology studies of egg pre-diapause stages.
Authors: Kamil Erguler; Stephanie E Smith-Unna; Joanna Waldock; Yiannis Proestos; George K Christophides; Jos Lelieveld; Paul E Parham Journal: PLoS One Date: 2016-02-12 Impact factor: 3.240
Authors: Annelise Tran; Morgan Mangeas; Marie Demarchi; Emmanuel Roux; Pascal Degenne; Marion Haramboure; Gilbert Le Goff; David Damiens; Louis-Clément Gouagna; Vincent Herbreteau; Jean-Sébastien Dehecq Journal: PLoS One Date: 2020-01-17 Impact factor: 3.240