Modeling boll maturation period, seed growth, protein, and oil content of cotton (gossypium hirsutum l.) in china
- English abstract
- The simulation of cottonseed (Gossypium hirsutum L.) growth is still an area of great uncertainty,
especially in the process of cottonseed quality formation. A simple process-based model was developed
to predict cotton bollmaturation period and simulate cottonseed biomass accumulation, protein, and oil
content. The cotton boll maturation period module took solar radiation and N nutrition factors into
account in addition to temperature and variety maturity profile. Based on the hypothesis that the
accumulation of biomass, oil, and protein are mainly sink-determined, the model was developed by
considering parameters of cultivar characteristics, weather (temperature and solar radiation), and crop
management variables (precisely N supply). The subtending leaf N concentration of cotton boll was
simulated by a new semi-empiricalmodel, and worked as the direct indicator of the N nutrition effect on
cottonseed growth and development. The model was calibrated using data obtained in experiment
conducted in Nanjing (the lower reaches of Yangtze River Valley) in 2005 and 2006. The model was then
tested using two field experimental data sets. One was obtained in Nanjing, China in 2007, and the other
in the Yellow River Valley (Xuzhou and Anyang) and the lower reaches of Yangtze River Valley (Huaian),
China in 2005. The simulated values of boll maturation period by the model were very consistent with
the observed values, with root mean square error (RMSE) lower than 3 days. The RMSE of cottonseed dry
weight, protein content, and oil content predictions were 8.9 mg seed1, 2.19%, and 2.71%, respectively.
The result showed that the model is sufficiently robust to predict the cotton boll maturation period,
cottonseed dry weight, and quality in wide range of conditions. It is not only a necessary component of
cotton growth model, but also provides a good platform for further study in modeling cottonseed protein
and oil yield.