Section: New Results

Methods for the Applications

Optimization of Phenotyping based on a Parameter Selection Methodology

The model Cornflo is a functional plant growth model simulating Corn's growth and yield. Based on it, the classification of environmental scenarios is researched in term of their influences to corn's yield, and their parameter estimation capabilities for Cornflo parameters. The initial qualitative analysis of parameter estimation results shows that environmental scenarios' classification benefit estimation accuracy and identifiability. Currently this project is researched from three aspects. Firstly, different clustering techniques are tested to find the most proper scenarios categories for parameter estimation. Secondly, the scenarios clusters are used for botanical experiments optimization, such as the selection of experimental locations. Lastly, parameter estimation is optimized and researched in a practical use for plant growth models.

Plant-Soil interactoin and Optimal Control of Irrigation

This work is performed in collaboration with JC Mailhol (Cemagref). Irrigation scheduling is an important issue for crop management, in a general context of limited water resources and increasing concern about agricultural productivity. Methods to optimize crop irrigation should take into account the impact of water stress on plant growth and the water balance in the plant-soil-atmosphere system. For this purpose, different plant-soil interaction models are proposed to simulate the functional plant growth. In particular, a compartment plant model is designed to integrate water stress impact on different main physiological processes of crop: biomass production, biomass allocation, and foliar senescence. This model is applied and calibrated for maize, in order to predict the harvest index according to the stress undergone by crop during its whole cycle. As for the optimal control problem of irrigation, it can be formulated by considering a price for the crop yield and for the water resource. Dynamic programming is then applied to the plant-soil system to determine an optimal irrigation strategy.