Changes of kernel weight and carbohydrate during milky maturity stage and their regression analysis with temperature and rainfall in {\sl sh}--2 sweet corn

The changes of kernel weight and carbohydrate in the kernel of sh-2 sweet corn during the milky maturity stage using different sowing stage in summer and their regression analysis with temperature and rainfall are investigated. The results show that the changes of total soluble sugar, fruit sugar, cane sugar in the kernels are obviously different between two sowing stages. In summer, the early sowing can increase the kernel fresh and dry weight, filling speed and the contents of total soluble sugar and starch in milky maturity stage. It suggests that the early sowing in summer can improve yield and profit to keeping special sweet flavor in supersweet corn. From transplant to harvest phase, T (temperature range per day), K (accumulated effective temperature) and RF (rainfall) are the main factors affecting the kernel fresh and dry weight and the contents of total soluble sugar, fruit sugar, cane sugar and starch in kernels during milky maturity stage. K and RF show positive correlation. From pollination to harvest phase, K was the main affecting factor. There are positive correlations between K and the kernel fresh and dry weight, the contents of fruit sugar and starch and negative correlation between K and the content of cane sugar in kernels of sh-2 supersweet corn.