Rape is a main oil crop in our country. Rice - oilseed rape rotation cultivation mode is one of the main cultivation mode in South China. The water remained in the field after the rice harvest often has influence on germination and growth of oilseed rape. In addition, moist and rainy winter in south China usually results in the moisture and waterlogging damage to the seedling and the decline of production. Many other cultivation measures adopted to alleviate the damage failed because they are manpow...