Authors:
Pablo Affortit | IRD | France
Dr. Awa Faye | ISRA | Senegal
Dr. Dylan Jones | University of Nottingham | United Kingdom
Dr. Ezenwoko Benson | University of Nottingham | United Kingdom
Dr. James Burridge | IRD | France
Dr. Bassirou Sine | ISRA | Senegal
Dr. Sebastian Arenas-Jimenez | IRD | France
Princia Nakombo-Gbassault | IRD | France
Dr. Rahul Bhosale | University of Nottingham | United Kingdom
Prof. Dr. Tony Pridmore | University of Nottingham | United Kingdom
Dr. Vincent Vadez | IRD | France
Dr. Ndjido Kane | ISRA | Senegal
Prof. Dr. Malcolm Bennett | University of Nottingham | United Kingdom
Dr Laurent Laplaze | Institut de Recherche pour le Développement | France
Dr. Darren Wells | University of Nottingham | United Kingdom
Dr. Jonathan Atkinson | University of Nottingham | United Kingdom
Dr. Alexandre Grondin | IRD | France
In West Africa, cereals production per capita is declining due to the fast growth in population outpacing the increase in food production. Moreover, several models predict that global changes will reduce cereals yield in this region. To achieve future food security, it is therefore necessary to improve productivity and resilience through the combined development of adapted varieties and agricultural practices. Pearl millet is a key cereal for food security in sub-Saharan Africa. It is mostly grown in areas with limited agronomic potential characterized by low rainfall and low-fertility soils.
Root traits represent potential new targets for breeding pearl millet varieties more resilient to abiotic stresses and more adapted to future climate scenarios. The aim of this work was to characterize the main water stress pattern faced by pearl millet in West Africa and to identify root traits that contribute to tolerance to this stress.
Crop modelling revealed that vegetative drought stress is a major constraint in the Sahel. Subsequently, a panel of 160 newly re-sequenced inbred lines was grown under irrigated and vegetative drought stress over two years in field conditions in Senegal and was phenotyped for root architectural and anatomical traits, as well as yield components traits. We observed a large diversity of response to drought stress in this panel, for root traits and yield stress tolerance indexes. We found that some root vasculature traits were associated with tolerance to vegetative drought stress. Further physiological studies suggest a link between metaxylem traits and transpiration efficiency and suggest an overall strategy to deal with vegetative stress. QTLs controlling these traits were identified by association genetics. Our results could provide new avenue