Adaptability of Hybrid-Maize model and potential productivity estimation of spring maize on dry highland of loess plateau

On the basis of verification of the Hybrid-Maize model in the maize production system on the dry highland of loess plateau with field experiment in 2007, the Hybrid-Maize model was used to simulate the potential productivity of spring maize on the dry highland of loess plateau. The maize yield potential data were obtained between 1990 and 2007. The results indicated that the Hybrid-Maize model had a good simulation effect on the dry highland of loess plateau. Correlation analysis indicated that there was a highly significant linear correlation between simulated data and observed data of total biomass, stalk biomass and grain yield, and the coefficients of determination were 0.9469, 0.8164 and 0.9650, respectively, the regression coefficients were 1.019, 0.9787 and 1.1844, respectively, close to 1. Annual photosynthetic- temperature potential productivity and climate potential productivity on the dry highland of loess plateau were different with different varieties. As for impact-typed maize, annual photosynthetic-temperature grain yield and total biomass were 13.25 t/hm2 and 22.45 t/hm2, respectively, and for flat-typed maize they were 12.32 t/hm2 and 20.62 t/hm2, respectively. The annual variation of photosynthetic-temperature potential productivity was low. The climate grain yield and total biomass were 11.94 t/hm2 and 19.94 t/hm2 for impact-typed maize, respectively, and those were 11.37 t/hm2 and 18.36 t/hm2 for flat-typed maize, respectively. The annual variation of climate potential productivity was high. The yield potential exploration of maize on the dry highland of loess plateau is dependent mainly on improving planting-density and soil water condition, therefore, the Hybrid-Maize model has good application value on guiding high yield cultivation of maize.