Evo-Devo of the Inflorescence Group
The EDI group focuses its research studies on inflorescence development and its evolution, with special emphasis on rice (Oryza sativa), a major cereal playing a key role in world food security. Our research is often based on comparative analyses of contrasting species or varieties and includes, in addition to cultivated rice species, other monocot groups such as the tribe Oryzeae and the family Arecaceae (palms). Our work is conducted in collaboration with other groups in Montpellier (e.g. researchers at CIRAD and the University of Montpellier) and also nationally and internationally (e.g. Italy, Austria, Australia, Colombia, Switzerland), with a special partner laboratory in Vietnam: the RICE International Joint Laboratory, co-partnered by the AGI (Agricultural Genetics Institute) and the University of Science and Technology of Hanoi (USTH) along with the French institutes IRD and CIRAD.
Inflorescence structure is one of the most illustrative characters of biodiversity in angiosperms. This morphological feature is often targeted during domestication and plant breeding as it is directly linked to yield potential. However, despite the great biological and human importance of the inflorescence, the regulatory mechanisms that explain its structural diversity and evolution remain little understood. Our research projects address the overall objective of characterising regulatory mechanisms that govern inflorescence development and their relationship with the evolution of inflorescence biodiversity and environment-dependent plasticity. In this way we aim firstly to better understand how inflorescence structural diversity has evolved in monocots and secondly to identify genes and alleles that might be useful in breeding programmes for the production of new genotypes better adapted to specific environments.
Panicle diversity in rice (left); morphometric analysis of panicle structure (middle); young inflorescence viewed under binocular microscope (top right); spatial pattern of gene expression in the inflorescence meristem revealed in situ hybridisation (bottom right).
Our primary experimental model is the Oryza genus (AA genome) within which contrasting inflorescence structures are observed between cultivated rice species and their wild relatives. More widely within the monocots, we will also be focusing attention on other members of the tribe Oryzeae and on the palm family (Arecaceae). Our research programme benefits from the wide range of genetic and genomic resources that are available or being developed for Asian and African rice species, which form the basis of studies for several different groups within our research unit. By combining morphological characterisation, analyses of genome expression and structure, modelling (of architecture and gene networks) and functional approaches, we aim to investigate the relationship between gene networks and inflorescence morphology in the following contexts:
The evolution of inflorescence architecture in the tribe Oryzeae and other tropical monocots
The relationship between inflorescence architectural diversity and the mechanisms that control meristem identity will be investigated. This approach will allow us to compare how inflorescence diversity has been genetically governed in two different contexts: domestication by mankind; and the natural process of speciation.
Pacaya palm (Chamaedorea tepejilote) plantation with immature inflorescences ready for harvesting, still enclosed in bracts (left); comestible pacaya inflorescence displaying heavily branched “patush” form (right).
Architectural plasticity in response to the environment
Relationships between inflorescence architecture, grain yield and environmental conditions will be addressed. This will allow us to assess the impact of different environmental and physiological factors on the development of the panicle and its architecture, particularly in relation to yield. Studies will also be carried out on panicle morphological plasticity in varieties of African and Asian rice in response to changing environments.
Ongoing funded projects
- EVOREPRICE (FIRST Agropolis Cariplo) - Coordinator S. Jouannic - 2013/2016
- Male Domestics (OpenScience Agropolis) - Coordinator J. Tregear - 2013/2015
- Dr. Stefan Jouannic, IRD research scientist, group leader
- Dr. James Tregear, IRD research scientist
- Dr. Helen Adam, IRD research scientist
- Dr. Thomas Harrop, Postdoctoral researcher 2014-2016 (Agropolis Cariplo)
Principal national and international collaborations:
- INERA (Burkina-Faso)
- AfricaRice (Benin)
- CIAT (Colombia)
- IRRI (Philippines)
- C. Godin (Virtual Plants, UMR AGAP, Montpellier)
- C. Scutt (ENS Lyon)
- M. Kater (UNIMI, Milan-Italy)
- T. Lafarge (WFP UMR AGAP, Montpellier)
- A. Dievart (DAR, UMR AGAP, Montpellier)
- X. Sirault (CSIRO Plant Industry, Canberra, Australia)
- Y. Staedler (University of Vienna, Austria)
- F. Stauffer (CJB Geneva Switzerland)
- X. Marquínez (National University of Colombia
- JJ. Castillo Mont (University San Carlos de Guatemala)
- IRD Montpellier (France)
- LMI RICE (Hanoi, Vietnam)