宋代的双季稻

宋代虽然有早稻和晚稻的名称 ,却并不是现代意义上的双季稻 ,但这并不能否定宋代有双季稻的存在。宋代存在再生、间作和连作三种形式的双季稻。再生稻 ,又名再熟稻、稻孙、二稻、传稻、孕稻、魏撩、再撩、再生禾、女禾等 ,分布于两浙、淮南、江南、福建和湖北等地。间作稻 ,又名寄生 ,主要分布在浙东一带。连作稻 ,在宋代虽然没有专门的名称 ,但却出现了许多连作稻的品种 ,如江苏的乌口稻、浙江的乌和第二遍、江西的黄穋禾、福建的和献台、岭南的月禾等等。另外 ,在宋代的稻品种中 ,还发现了有些品种既当早稻又充晚稻的现象 ,也应是双季连作的结果。宋代的连作双季稻分布虽广 ,但由于品种不佳、产量不高、季节和劳动力的矛盾、放牧的需要、肥水条件的限制、投入产出率低等等原因 ,双季稻总的种植面积并不大 ,在粮食生产中的作用如同凤毛麟角。宋代的双季稻大多都是在原有的品种基础上发展起来的 ,与当时引进的早熟而耐旱的品种占城稻关系不大。

Double-Harvest Rice in the Song Dynasty

The so-called "early rice" and "late rice" in the Song Dynasty were not the same as double-harvest or double-cropping rice in the modern sense, but the double-harvest rice did exist in the said dynasty. There were then three types of double-harvest rice: ratooning rice, intercropping rice and continuous cropping rice. Ratooning rice or re-harvest rice, grandson of rice, second rice, heir rice and pregnant rice were distributed mainly in Zhejiang, Jiangnan (including present Jiangxi and southern Anhui), Huainan (northern Anhui), Fujian and Hubei. Intercropping rice, also named Jisheng, was mostly distributed in the southern part of Zhejiang. Though there was no specific name for continuous cropping rice in the Song Dynasty, there were still many varieties of rice for continuous cropping, such as Wukou (black mouth) rice in Jiangsu, Wuxian and the second in Zhejiang, Huangluhe rice in Jiangxi, shu and Xiantai in Fujian, and Yuehe in Lingnan (now Guangdong and Guangxi). Furthermore, there were some varieties which were used not only for early rice but also for late rice, and this should be the outcome of continuous cropping. Due to the inferiority of variety, low output, the conflict between growing season and labour, needs for pasture, and the shortage of manure and water, however, the total acreage of double-harvest rice was not very large, and the role it played in the supply of food in the Song Dynasty was also insignificant. The development of double-harvest rice in the Song Dynasty depended mainly on old varieties, and had little to do with the then imported Champa rice featured by its early ripening and drought resistance.