A successive time-to-event model of phyllochron dynamics for hypothesis testing: application to the analysis of genetic and environmental effects in maize
2023
Plancade, Sandra | Marchadier, Elodie | Huet, Sylvie | Ressayre, Adrienne | Noûs, Camille | Dillmann, Christine | Unité de Mathématiques et Informatique Appliquées de Toulouse (MIAT INRAE) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Mathématiques et Informatique Appliquées du Génome à l'Environnement [Jouy-En-Josas] (MaIAGE) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Génétique Quantitative et Evolution - Le Moulon (Génétique Végétale) (GQE-Le Moulon) ; AgroParisTech-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire Cogitamus = Cogitamus Laboratory | BASC labex (ITEMAIZE Project) supported by IDEX Paris-Saclay | ANR-11-LABX-0034,BASC,Biodiversité, Agroécosystèmes, Société, Climat(2011)
International audience
显示更多 [+] 显示较少 [-]英语. Background: The time between the appearance of successive leaves, or phyllochron, characterizes the vegetative development of annual plants. Hypothesis testing models, which allow the comparison of phyllochrons between genetic groups and/or environmental conditions, are usually based on regression of thermal time on the number of leaves; most of the time a constant leaf appearance rate is assumed. However regression models ignore auto-correlation of the leaf number process and may lead to biased testing procedures. Moreover, the hypothesis of constant leaf appearance rate may be too restrictive.Methods: We propose a stochastic process model in which emergence of new leaves is considered to result from successive time-to-events. This model provides a flexible and more accurate modeling as well as unbiased testing procedures. It was applied to an original maize dataset collected in the field over three years on plants originating from two divergent selection experiments for flowering time in two maize inbred lines.Results and conclusion: We showed that the main differences in phyllochron were not observed between selection populations but rather between ancestral lines, years of experimentation and leaf ranks. Our results highlight a strong departure from the assumption of a constant leaf appearance rate over a season which could be related to climate variations, even if the impact of individual climate variables could not be clearly determined.
显示更多 [+] 显示较少 [-]