Japonica rice (Medium to short grain nonglutinous rice or Japonica rice) is the fruit of japonica type non glutinous rice, which has the characteristics of cold tolerance, weak light tolerance and high temperature tolerance. It is mainly distributed in northern China, the middle and lower reaches of the Yangtze River, the high-altitude areas of Yunnan Guizhou Plateau with low temperature, South Korea, Japan, etc.

Japonica rice grains are generally oval, short, 1.4-2.9 times longer than the width, long and dense fluff, long awn, thick husk, small or no chalkiness, many horny grains, difficult to produce broken rice during processing, high rice yield, small swelling and high viscosity.

Japonica rice can be divided into early japonica rice, medium japonica rice and late japonica rice according to the different sowing date, growth period and maturity period. Generally, the growth period of early japonica rice is 90~180 days, that of medium japonica rice is 125~150 days, and that of late japonica rice is 150~180 days.

　　 The Rice Growing Period of the Main Japonica Rice Producing Provinces in China

Source: Agricultural Time Database of China Crop Information Network

The storage of rice has three obvious characteristics: easy aging, not resistant to high temperature; It is easy to get hot, mildew and sprout; Yellowing easily. The principle of rice storage is "dry, low temperature and airtight". At present, the storage measures commonly used in warehouses mainly include: ① controlling the moisture content of rice; ② Remove rice impurities; ③ Classified storage of rice; ④ Ventilation and cooling of rice; ⑤ Control of rice pests; ⑥ Seal the rice grain pile.

　　 Regulations on Japonica Rice in GB/T 20569-2006 Rules for Determining the Storage Quality of Rice

In recent years, with the continuous rigid increase in the demand for japonica rice, the high price, the high efficiency of farmers' planting, and the support of the country's increasing adjustment of high-quality rice planting structure and other factors, the planting area of japonica rice (especially high-quality varieties) in China has been increasing, with significant growth in the northeast region, In addition, a few indica rice producing areas in the south also began to try to plant japonica rice (Hunan, Jiangxi and other places). In addition, the improvement of cultivation technology and the expansion of water resources have gradually improved the quality of japonica rice. The commodity volume has remained high year after year, and the quality has also been further improved. The processed japonica rice has bright and clean grains, sweet taste, and is highly recognized by residents, At present, more than 50% of the residents across the country are eating japonica rice, and high-quality varieties such as Daohuaxiang, super rice and high-quality long grain are favored by the majority of people.