Original article: An optimal control methodology for plant growth-Case study of a water supply problem of sunflower

  • Authors:
  • Lin Wu;François-Xavier Le Dimet;Philippe de Reffye;Bao-Gang Hu;Paul-Henry Cournède;Meng-Zhen Kang

  • Affiliations:
  • Université Paris-Est, CEREA, joint laboratory Ecole des Ponts ParisTech - EDF R&D, Marne la Valléée F-77455, France and INRIA, Clime, Rocquencourt F-78153, France;Université Joseph Fourier, Lab. Jean Kuntzmann (LJK), Grenoble F-38041, France and INRIA, MOISE, Grenoble F-38041, France;INRIA, DigiPlante, Orsay F-91893, France and CIRAD, UMR AMAP, Montpellier F-34000, France;Chinese Academy of Sciences, Institute of Automation, LIAMA, Beijing 100080, China;INRIA, DigiPlante, Orsay F-91893, France and Ecole Centrale Paris, Laboratory of Applied Mathematics, Chítenay-Malabry F-92295, France;Chinese Academy of Sciences, Institute of Automation, LIAMA, Beijing 100080, China

  • Venue:
  • Mathematics and Computers in Simulation
  • Year:
  • 2012

Quantified Score

Hi-index 0.00

Visualization

Abstract

An optimal control methodology is proposed for plant growth. This methodology is demonstrated by solving a water supply problem for optimal sunflower fruit filling. The functional-structural sunflower growth is described by a dynamical system given soil water conditions. Numerical solutions are obtained through an iterative optimization procedure, in which the gradients of the objective function, i.e. the sunflower fruit weight, are calculated efficiently either with adjoint modeling or by differentiation algorithms. Further improvements in sunflower yield have been found compared to those obtained using genetic algorithms in our previous studies. The optimal water supplies adapt to the fruit filling. For instance, during the mid-season growth, the supply frequency condenses and the supply amplitude peaks. By contrast, much less supplies are needed during the early and ending growth stages. The supply frequency is a determining factor, whereas the sunflower growth is less sensitive to the time and amount of one specific irrigation. These optimization results agree with common qualitative agronomic practices. Moreover they provide more precise quantitative control for sunflower growth.