Research advances of cotton dynamic simulation models

Cotton models could be divided into three categories, physiological models, structural models, and functional-structural models. In this paper, peer review of advantages and limitations of each category of models provides an important quality-control step in the development of the cotton models. It could be concluded that cotton simulation in the future should focus on the functional-structural cotton models, which intends to bridge the gap between physiological models and structural models. However, functional-structural models of cotton still have some limitations, which are: accurate simulation of light microclimate in the canopy has not been realized; distribution of photoassimilation is less well studied; and coupling simulation of the shoot and root system is not included. Several recommendations for further improvement of the functional-structural model were also put forward in this review: light microclimate in the cotton canopy could be modeled by surface-based model; distribution of photoassimilation of shoot could be simulated by source-sink model; and coupling simulation of the shoot and root system could be realized by connecting the shoot, which is regarded as a source of assimilation, with a growing branching structure of root.