The Greater Phenotypic Homeostasis of the Allopolyploid Coffea arabica Improved the Transcriptional Homeostasis Over that of Both Diploid Parents.
Polyploidy impacts the diversity of plant species, giving rise to novel phenotypes and leading to ecological diversification. In order to observe adaptive and evolutionary capacities of polyploids, we compared the growth, primary metabolism and transcriptomic expression level in the leaves of the newly formed allotetraploid Coffea arabica species compared with its two diploid parental species (Coffea eugenioides and Coffea canephora), exposed to four thermal regimes (TRs; 18-14, 23-19, 28-24 and 33-29°C). The growth rate of the allopolyploid C. arabica was similar to that of C. canephora under the hottest TR and that of C. eugenioides under the coldest TR. For metabolite contents measured at the hottest TR, the allopolyploid showed similar behavior to C. canephora, the parent which tolerates higher growth temperatures in the natural environment. However, at the coldest TR, the allopolyploid displayed higher sucrose, raffinose and ABA contents than those of its two parents and similar linolenic acid leaf composition and Chl content to those of C. eugenioides. At the gene expression level, few differences between the allopolyploid and its parents were observed for studied genes linked to photosynthesis, respiration and the circadian clock, whereas genes linked to redox activity showed a greater capacity of the allopolyploid for homeostasis. Finally, we found that the overall transcriptional response to TRs of the allopolyploid was more homeostatic compared with its parents. This better transcriptional homeostasis of the allopolyploid C. arabica afforded a greater phenotypic homeostasis when faced with environments that are unsuited to the diploid parental species.
CIRAD, UMR IPME, 911 Avenue Agropolis, BP 64501, 34394 Montpellier, France benoit.bertrand@cirad.fr.
Benoît
B
Bertrand
University of Neuchâtel, Institute of Biology, Laboratory of Evolutionary Botany, Emile Argand 11, CP 158, 2000 Neuchâtel, Switzerland.
Amélie
A
Bardil
Université de Reims, Unité de Recherche Vignes et Vins de Champagne, Laboratoire de stress, défenses et reproduction des plantes, Campus Moulin de la Housse, 51687 Reims Cedex 2, France.
Hélène
H
Baraille
IRD, UMR DIADE, 911 Avenue Agropolis, BP 64501, 34394 Montpellier, France.
Stéphane
S
Dussert
IRD, UMR DIADE, 911 Avenue Agropolis, BP 64501, 34394 Montpellier, France.
Sylvie
S
Doulbeau
CNRS, Montpellier GenomiX, c/o Institut de Génomique Fonctionnelle, 141 rue de la Cardonille, Montpellier Cedex 34, France.
Emeric
E
Dubois
CNRS, Montpellier GenomiX, c/o Institut de Génomique Fonctionnelle, 141 rue de la Cardonille, Montpellier Cedex 34, France.
Dany
D
Severac
IRD, UMR IPME, 911 Avenue Agropolis, BP 64501, 34394 Montpellier, France.
Alexis
A
Dereeper
CIRAD, UMR IPME, 911 Avenue Agropolis, BP 64501, 34394 Montpellier, France.
Hervé
H
Etienne
D040503:Coffea / Q000235:genetics / Q000378:metabolism*; D004171:Diploidy; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D018745:Genome, Plant / Q000235:genetics
Coffea arabica; Homeostasis; Natural allopolyploid; Primary metabolism; Temperature; Transcriptomic expression level