DENIS Manon

PhD student
in Plant Ecophysiology

Team: MAGE 

I graduated with a master’s degree in Biosciences from the Ecole Normale Supérieur of Lyon in 2023, as well as a master degree in Biodiversity, Ecology and Evolution with a specialization in Ecological Modelling from University of Rennes 1 in 2025. 
I’m currently pursuing a PhD in two differents units of INRAE : LEPSE and AGAP institut.

Start of the PhD:  1.10.2025

Subject: Comparative study of intra and interspecific genetic variability of ecophysiological component underlying drought tolerance in sorghum and maize

Abstract
In the context of climate change, which is intensifying competition over water resources, irrigated grain maize raises legitimate concerns about its long-term sustainability—both economically and environmentally. By contrast, grain sorghum is increasingly viewed as a promising alternative. Sorghum benefits from similar management practices and end uses as maize, yet it generally requires fewer agricultural inputs and shows greater tolerance to heat and drought stress. This perception, however, rests largely on farm-level observations, with relatively few rigorous comparative studies conducted.
This PhD project aims to challenge prevailing assumptions about maize and sorghum tolerance, seeking to provide a clearer picture of the actual adaptive potential of both crops. These two species have developed different adaptation strategies in response to stress, mainly due to different selection pressures. The contrasting adaptation strategies may arise from differences in: (i) stress tolerance per se; (ii) stress avoidance; and/or (iii) stress escape. For instance, sorghum varieties are generally more sensitive to low temperatures, leading to later sowing and shorter growth duration in Europe compared to maize. While longer crop cycles enhance light interception and yield potential under irrigation, shorter cycles can provide an advantage in avoiding heat or drought stress during critical periods. This raises an important question: could “non-elite” maize cultivars, or maize types resembling sorghum in being short, early, and robust (“sorghum-like” maize), perform as well as sorghum under hot and dry conditions?
To address this, the PhD project will explore the variability of stress responses within diverse genetic panels. The study will investigate maize and sorghum responses to drought and heat, focusing on both intrinsic stress tolerance mechanisms and stress escape strategies such as crop duration and cold sensitivity.

Key words:  genetic variability, maize, sorghum, drought tolerance.

Supervisors
UMR LEPSE, MAGE team: PARENT Boris (PhD supervisor)
AGAP Institut, Phenomal team: GIAUFFRET Catherine (co-supervisor)