RESEARCH ON SINGLE-PARAMETER LOGISTIC MODEL FOR RELATIVE PLANT HEIGHT AND RELATIVE DRY MATTER OF WINTER WHEAT (TRITICUMAESTIVUM L.) AND SUMMER MAIZE (ZEA MAYS L.)

Logistic model has been widely used in simulating plant height and dry matter accumulation (DMA). However, the parameters of logistic model vary greatly under different crop cultivar, cultivation environment and weather conditions, which limits the application range of the model. In order to increase the applicability of the model, the maximum DMA, maximum plant height, and maximum growing degree days of typical crops were set to 1. Based on the method of normalization, the parameters a and b of the logistic model were estimated using a series of field trial data. The results showed that a/b values were a relatively stable constant due to a/b represented the peak of crop growth rate. Based on the above opinion, the single-parameter logistic models for plant height and DMA of typical food crops were established. The accuracy of the single-parameter models was evaluated, showing that the singleparameter models can accurately reflect the dynamic characteristics of plant height and DMA. These results can provide theoretical support for precise regulation and prediction of plant height and dry matter accumulation of two food crops.