Effects of different seeding dates on the first cropping and ratoon of super rice.

In order to make full use of light resources, temperature and field in one-cropping middle rice zone, super rice variety Zhongzheyou 1 was used to study the effects of different seeding dates on the yields of the first cropping and ratoon rice. The results showed that the first cropping of rice variety Zhongzheyou 1 (sown during March,19 to April,8 in one cropping middle zone)could be harvested before August, 20 and ratoon could be harvested in the first ten-day of November. But the yield of super rice was the highest as sowing around March,19 and the total yield of two cropping rice reached 14197.5kg/ha. Therefore, it could be extended in one-cropping middle rice zone.