The main things is the Russia, china, Poland, us. In china, the biggest one is accounting for 1/3..
     Ningxia xihaigu is full of yam. The government plan the basis for the test. Every year, giving the reward to the good farmers. It is the biggest basis for the ningxia, the normal one differs from the type. There are two parts, the yellow and pale yellow. The bottom is round and skin white. With it grows, it has the fruit of white, blue and yellow color. All the land are different from the area, at first it is easy get the hurt from the virus and insect. We should pay more attention on it, and change the planting tech to enhance the new type.
     It is the main corp, just next to the corp and rice. Ningxia is the biggest one in china and then becoming the main things to change the food in village. In recent years, with the adjustment of the industry, it enlarge and becoming the main product in the ningxia.