Doktorand/PhD

INRAE presentation

The French National Research Institute for Agriculture, Food, and the Environment (INRAE) is a public research establishment. It is a community of 12,000 people with more than 200 research units and 42 experimental units located throughout France. The institute is among the world leaders in agricultural and food sciences, in plant and animal sciences, and is 11^th in the world in ecology and environment. INRAE’s main goal is to be a key player in the transitions necessary to address major global challenges. In the face of the increase in population, climate change, scarcity of resources and decline in biodiversity, the institute develops solutions for multiperformance agriculture, high quality food and sustainable management of resources and ecosystems.

Work environment, missions and activities

Rice is the most important agricultural production in Cambodia. Farmers grow rice for food and
income. Rice crops receive enormous amounts of pesticides, up to 13 pesticide treatments per
cropping season in certain regions (Matsukawa, 2016). Farmers often mix several pesticide products
and spray preventive treatments. Recently, several rice exportations to Europe have been refused
due to excessive content in pesticide residues. There is an urgent need for a reduction of pesticide
used in rice crops in Cambodia.
A better characterization of the main drivers of biotic stresses will permit to limit useless treatments
and to adapt cropping practices to production situations, especially to the local biodiversity.
Agroecological Crop Protection (ACP) is mainly based on ecosystemic services provided by
biodiversity and soil health (Ratnadass et al. 2012; Barzman et al. 2015; Deguine et al, 2017), and
strongly depends on cropping practices. Different projects in Cambodia aim at developing, with
farmers, more resilient rice-based cropping systems, including the introduction of biodiversity within
fields and in their immediate surroundings. These cropping systems will impact dynamics of animal
pests, diseases and weeds and will therefore permit a reduction in pesticide use. Major steps
towards a reduction of pesticides are i) the analysis of the relationship between injuries caused by
animal pests, diseases and weeds with the risk of yield and/or quality loss; ii) the identification of
means to limit pest development.
The aim of the PhD will be the design of a dynamic model to evaluate the risk of yield and quality loss
in a specific situation of biotic constraints, as a function of the cropping system. In order to do so, it
will combine models of rice development like DSSAT (Jones et al., 2003), which simulates the effect
of environment on crop growth, and multipest models like WheatPest (Willocquet et al., 2008),
implemented with the modeling platform Xpest (xpest.inra.fr; Aubertot et al, 2015).
The PhD study will focus on the design of a unique model that will represent the effects of the
cropping system and the production situation on yield production, injury profile and the associated
damages.

The main research questions are:
1. What are the effects of cropping systems on biotic constraints in rice crops in Cambodia?
How do they interact with planned biodiversity?
2. What are the damages associated with a given injury profile?
3. How to create a dynamic model representing abiotic and biotic stresses under the influence
of cropping practices?
4. Using simulations, how to determine the best combinations of cropping for ACP in rice
(Aubertot et Robin, 2013)?
Multi-year experimental trials will be set-up in Cambodia, especially on the experimental farm of the
University of Battambang, and in interaction with a team of local researchers from the Institute of
Technology of Cambodia, the Royal University of Agriculture and University of Battambang. In
addition to field experiments in Cambodia, the PhD student will spend some time in France, at INRAE
Occitanie-Toulouse to perform literature review, and modeling work.

The work will be conducted according to four axes
- Bibliography on i) crop growth models and data sets useful for rice growth without biotic stresses ii)
epidemiological or demographic models of major rice biotic constraints iii) models of injury profile of
biotic constraints found in Cambodia.
- Measure and analyze in experimental trials of the impact of cropping systems (conventional, or
including rotation with cover crops or rotation with reduced tillage) on rice growth, yield, and
susceptibility to animal pests, diseases, and weeds.
- Integrate the results in a complete model predicting the impact of biotic constraints on yield in
different cropping systems
- Use simulations to identify ACP strategies and reduce the use of pesticides in rice fields
A conceptual model will be eveloped at the beginning of the PhD study and adapted as a function of
the knowledge gained. 

Training and skills

Master's degree/Engineering degree

For this interdisciplinary project, we look for an enthusiastic person with an appropriate MSc degree
in agronomy, with strong analytical skills and interest in participatory research with farmers and
other stakeholders. Experience with experimental work and/or modeling is an advantage. An interest
in research for development and living in an Asian country is necessary.
Good communication skills and proficiency in English (both oral and written) are a prerequisite.

INRAE's life quality

By joining our teams, you benefit from:

- 30 days of annual leave + 15 days "Reduction of Working Time" (for a full time);
- parenting support: CESU childcare, leisure services;
- skills development systems: training, career advise;
- social support: advice and listening, social assistance and loans;
- holiday and leisure services: holiday vouchers, accommodation at preferential rates;
- sports and cultural activities;
- collective catering.