A PHOTO-THERMAL MODEL FOR PREDICTING DEVELOPMENT AND QUALITY OF STANDARD CUT CHRYSANTHEMUM IN GREENHOUSES

In order to optimize the climate control for standard cut chrysanthemum production in greenhouse, a photo-thermal model for predicting development and external quality was developed based on the integrated effect of light and temperature.
For this purpose, experiments with different cultivars, planting dates and planting densities were carried out during 2005 and 2006 in multi-span plastic greenhouses in Shanghai.
The concept of physiological thermal and light effectiveness (PTLE) and its calculation method were proposed.
The relationships of PTLE to the development stage and quality indices of standard cut chrysanthemum were quantified.
Based on these relationships, a model for predicting standard cut chrysanthemum development and quality was developed.
Independent experimental data were used to validate the model.
The results show that the predicted results agree well with the measured ones.
Based on the 1:1 line, the root mean square error (RMSE) for development stages from cutting to planting, beginning of the short day period, visible bud and harvesting date were, respectively, 2.3, 2.9, 1.2 and 3.2 days; the relative prediction error (RSE) for such external quality indices as number of leaves unfolding per plant, leaf area per plant, plant height, stem diameter, internode length and flower diameter were 5.5%, 6.5%, 5.9%, 4.1%, 11.2% and 12.4%, respectively.
It can be concluded that the model developed in this study can give satisfactory predictions of development and quality of standard cut chrysanthemum and can be used for decision making for the optimization of light and temperature management for standard cut chrysanthemum production in greenhouses.

International Symposium on High Technology for Greenhouse System Management: Greensys2007

Jianfeng Dai, Weihong Luo, Zaiqiang Yang

PAR, temperature, day length, harvesting date, flower diameter

https://doi.org/10.17660/ActaHortic.2008.801.175