Combinatorial approaches to model development for predicting emergence and crop-weed competition

摘要

Combinatorial approaches to model development were used to predict emergence and crop-weed competition as affected by environmental factors. For emergence as affected by soil depth, the Gompertz curve was modified by incorporating either a logistic oran exponential model for parameters that varied with soil depth. This modified model simulated well the effect of soil depth on seedling emergence for rice and Echinochloa spp. For crop-weed competition as affected by herbicide at a range of doses, therectangular hyperbola was modified by incorporating a logistic model for the effect of herbicide dose on winter wheat grain yield at different densities of weed infestation. This model simulated well the effect of crop-weed competition and herbicide application on grain yield.