A rice farming system in which rice is planted and harvested in the same paddy field in two seasons a year. According to different cultivation methods, it can be divided into double cropping rice, interplanting rice and mixed cropping rice. In July 2020, the average yield per mu of early rice was 6 19.06 kg,1/0.7 kg, and that of late rice was 91/0.7 kg. Early rice and late rice achieve the goal of per mu yield 1500 kg.
Double-cropping rice has a long planting history in China, which was first recorded in Shan Hai Jing in the 3rd century BC. It is generally believed that "double cropping rice" and "double cropping rice" often mentioned in ancient books include ratooning rice, mixed cropping rice, intercropping rice and continuous cropping rice. , which embodies the diversity of rice absence system in China.
Extended data
Rice likes high temperature, high humidity and short sunshine, and has low requirements for soil, but paddy soil is the best. The lowest temperature of seedling germination is 10 ~ 12℃, and the optimum temperature is 28 ~ 32℃. The average daily temperature at tillering stage is above 20℃, and the optimum temperature for ear differentiation is around 30℃. Low temperature prolonged the differentiation of branches and glumes. The optimum heading temperature is 25 ~ 35℃. The optimum flowering temperature is about 30℃, lower than 20℃ or higher than 40℃, and pollination is seriously affected.
The relative humidity is 50 ~ 90%. The key period of fruiting is from panicle differentiation to full filling stage; The population with balanced nutritional status and high photosynthetic efficiency is of great significance to improve seed setting rate and grain weight. A lot of water and mineral nutrients are needed at heading and fruiting stage; At the same time, it is necessary to enhance the root activity and prolong the functional period of stems and leaves. It takes about 500 ~ 800 kg of water to form 1 kg of rice.
Baidu encyclopedia-rice
Baidu Encyclopedia-Double Cropping Rice