... largest in the world, the most widely distributed region was at 10 north latitude an official -18 of an official of non ... yield,in the Yangtze River Valley general cultural level of 10 tons, growing period without pest,but grains of sweet and ... and seeding rate:seeding when the soil temprature reach 10,Seeding Rate is 10-15kg/ha,drilling if cutting,sowing if grazing ...