Abstract: Crop growth is a continuous and dynamic process, and thus, the optimal meteorological indices for crop growth also change continuously. In this paper, the estimation algorithms of the daily available precipitation and the temporal interpolation methods of meteorological indices for crop growth were developed, and the climatic suitability model at daily scale was established, which was tested by the spring maize data of agro-meteorological stations in Northeast China. The simulated climatic suitability had significantly positive correlations with the height and 100-grain mass of spring maize. The correlation coefficient (R²) between the climatic suitability and the spring maize height was over 0.58 at vegetative growth stage, and over 0.45 at reproductive growth stage. The established climatic suitability model at daily scale could objectively reflect the interactions between crop growth and meteorological factors at vegetative growth stage and reproductive growth stage.

Key words: spring maize, meteorological index for crop growth, continuity of crop index, climatic suitability.