Responsable
Mebarek Lamara
Collaborateurs
Yves Bergeron, Annie DesRochers, Jean Beaulieu, Steeve Pepin, Jean Bousquet, Julie Godbout
Problématique
La migration assistée consiste à effectuer un déplacement des sources génétiques utilisées en reboisement de leur aire de répartition indigène vers de nouvelles zones où elles devraient évoluer à mesure que le climat change. L'évaluation du degré de tolérance des différentes sources génétiques aux stress environnementaux sévères, qui sont imprévisibles et peuvent avoir un effet considérable sur la survie et la croissance des plantations, notamment pendant la phase juvénile, permettrait d’optimiser le choix des sources de semences les mieux adaptées au climat futur. L’ajout de telles connaissances permettra de mettre en place des stratégies de migration assistée établies sur des bases scientifiques plus solides et tenant mieux compte de la grande multiplicité des effets potentiels des changements climatiques futurs.
Objectifs
Le projet a pour but de mieux caractériser les réponses écophysiologiques des populations d’épinette blanche (Picea glauca [Moench] Voss, EPB) aux différents stress environnementaux en conditions contrôlées et naturelles et d’identifier les traits fonctionnels et les mécanismes physiologiques impliqués dans ces réponses et leur régulation génétique en vue d’optimiser les règles de migration assistée des semences d’EPB appliquées par notre partenaire à ce projet, le MFFP. Le projet de recherche porte sur l’EPB, l’une des espèces les plus reboisées dans les différentes régions du Québec, avec un objectif annuel de 35M plants.
Méthodologie
Le projet proposé inclut des expériences en conditions contrôlées et en conditions naturelles. Les données recueillies lors de la réalisation de ces deux expériences seront utilisées pour développer un nouveau modèle de transfert de semences.
Retombées escomptées
Les résultats attendus de ce projet sont : 1) l’évaluation et la classification des différentes sources génétiques (vergers à graines d’EPB du MFFP) selon leur tolérance aux stress environnementaux (température, sécheresse et gel) dans les sites de plantation et en conditions contrôlées; 2) le développement d’un nouveau modèle de transfert multicritère qui permettra d’évaluer les risques associés à un déplacement en fonction de la distance de transfert et 3) le développement de nouvelles connaissances sur la performance des sources de semences lors de leur phase d’établissement lorsque soumises à de nouvelles conditions climatiques (printemps froids et humides, gels printaniers, etc.).
Applicabilité
Québec
Livrables
Lahcen Benomar, Jean Bousquet, Martin Perron, Jean Beaulieu, Mebarek Lamara. Tree Maladaptation Under Mid-Latitude Early Spring Warming and Late Cold Spell: Implications for Assisted Migration. 2022. Frontiers in Plant Science 13:920852
DOI : 10.3389/fpls.2022.920852
Global warming is predicted to extend the growing season of trees and plants, and advance spring phenology. However, intensification of extreme climate events in mid-latitude forests, from weakening of the jet stream and atmospheric blockings, may expose trees to increased risk associated with more frequent late-spring frosts. Still, little is known regarding the intraspecific variation in frost tolerance and how it may be shaped by local adaptation to the climate of seed origin. As part of an assisted migration trial located in different bioclimatic zones in the province of Quebec, Canada, and following an extensive late-spring frost that occurred at the end of May 2021, we evaluated the frost damages on various white spruce (Picea glauca) seed sources tested on three sites (south, central, and north). The severity of frost damages was assessed on 5,376 trees after the cold spell and an early spring warming which advanced bud flush by approximately 10 days on average. The frost damage rate was similar among sites and seed sources and averaged 99.8%. Frost damage severity was unrelated to the latitude of seed origin but was variable among sites. The proportion of severely damaged trees was higher in the northern site, followed by central and southern sites. The proportion of severely damaged trees was linearly and inversely related to tree height before the frost event. Apical growth cancelation was not significantly different among seed sources including local ones, and averaged 74, 46, and 22%, respectively, in central, northern, and southern plantation sites. This study provides recommendations to limit the loss of plantation productivity associated with such a succession of spring climate anomalies. Implications for seed transfer models in the context of climate change and productivity of spruce plantations are discussed in the light of lack of local adaptation to such pronounced climate instability and ensuing large-scale maladaptation.
Lahcen Benomar, Raëd Elferjani, Jill Hamilton, Greg A. O'Neill, Said Echchakoui, Yves Bergeron, Mebarek Lamara. Bibliometric Analysis of the Structure and Evolution of Research
on Assisted Migration 2022. Current Forestry Reports
DOI : 10.1007/s40725-022-00165-y
Assisted migration is increasingly proposed as a proactive management strategy to mitigate the consequences of maladaptation predicted under climate change. Exploring the social and academic structure of the field, its research gaps, and future research directions can help further the understanding and facilitate the implementation of assisted migration strategies. Here we used bibliometric analysis to examine the intellectual, social, and conceptual structures of assisted migration research to identify gaps and opportunities for future research. Bibliometric data based on publications on assisted migration were collected from Scopus and Web of Science databases using assisted migration and climate change or their synonyms as queries. Metadata were merged, processed and several networks were constructed.
Raëd Elferjani, Lahcen Benomar, Mina Momayyezi, Roberto Tognetti, Ülo Niinemets, Raju Y. Soolanayakanahally, Guillaume Théroux-Rancourt, Tiina Tosens, Francesco Ripullone, Simon Bilodeau-Gauthier, Mohammed S. Lamhamedi, Carlo Calfapietra, Mebarek Lamara. A meta-analysis of mesophyll conductance to CO2 in relation to major abiotic stresses in poplar species 2021. Journal of Experimental Botany erab127
DOI : 10.1093/jxb/erab127
Mesophyll conductance (gm) determines the diffusion of CO2 from the substomatal cavities to the site of carboxylation in the chloroplasts and represents a critical component of the diffusive limitation of photosynthesis. In this study, we evaluated the average effect sizes of different environmental constraints on gm in Populus spp., a forest tree model. We collected raw data of 815 A-Ci response curves from 26 datasets to estimate gm, using a single curve-fitting method to alleviate method-related bias. We performed a meta-analysis to assess the effects of different abiotic stresses on gm. We found a significant increase in gm from the bottom to the top of the canopy that was concomitant with the increase of maximum rate of carboxylation and light-saturated photosynthetic rate (Amax). gm was positively associated with increases in soil moisture and nutrient availability, but it was insensitive to increasing soil copper concentration, and it did not vary with atmospheric CO2 concentration. Our results showed that gm was strongly related to Amax and to a lesser extent to stomatal conductance (gs). Also, a negative exponential relationship was obtained between gm and specific leaf area, which may be used to scale-up gm within the canopy.
À venir
Avancement
En phase de démarrage
Organismes subventionnaires
MFFP, Coopérative, CRSNG-Alliance (en évaluation)
Financement annuel
190 724 $
Durée
2020-2024
Dernière mise à jour :
2022-04-06 00:13:40
